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Sample records for salmon spawning ground

  1. Spawning distribution of fall chinook salmon in the Snake River: Annual report 1999

    International Nuclear Information System (INIS)

    Garcia, Aaron P.

    2000-01-01

    This report is separated into 2 chapters. The chapters are (1) Progress toward determining the spawning distribution of supplemented fall chinook salmon in the Snake River in 1999; and (2) Fall chinook salmon spawning ground surveys in the Snake River, 1999

  2. Spatial and temporal variability of macroinvertebrates in spawning and non-spawning habitats during a salmon run in Southeast Alaska.

    Directory of Open Access Journals (Sweden)

    Emily Y Campbell

    Full Text Available Spawning salmon create patches of disturbance through redd digging which can reduce macroinvertebrate abundance and biomass in spawning habitat. We asked whether displaced invertebrates use non-spawning habitats as refugia in streams. Our study explored how the spatial and temporal distribution of macroinvertebrates changed during a pink salmon (Oncorhynchus gorbuscha spawning run and compared macroinvertebrates in spawning (riffle and non-spawning (refugia habitats in an Alaskan stream. Potential refugia included: pools, stream margins and the hyporheic zone, and we also sampled invertebrate drift. We predicted that macroinvertebrates would decline in riffles and increase in drift and refugia habitats during salmon spawning. We observed a reduction in the density, biomass and taxonomic richness of macroinvertebrates in riffles during spawning. There was no change in pool and margin invertebrate communities, except insect biomass declined in pools during the spawning period. Macroinvertebrate density was greater in the hyporheic zone and macroinvertebrate density and richness increased in the drift during spawning. We observed significant invertebrate declines within spawning habitat; however in non-spawning habitat, there were less pronounced changes in invertebrate density and richness. The results observed may be due to spawning-related disturbances, insect phenology, or other variables. We propose that certain in-stream habitats could be important for the persistence of macroinvertebrates during salmon spawning in a Southeast Alaskan stream.

  3. Spatial and temporal variability of macroinvertebrates in spawning and non-spawning habitats during a salmon run in Southeast Alaska.

    Science.gov (United States)

    Campbell, Emily Y; Merritt, Richard W; Cummins, Kenneth W; Benbow, M Eric

    2012-01-01

    Spawning salmon create patches of disturbance through redd digging which can reduce macroinvertebrate abundance and biomass in spawning habitat. We asked whether displaced invertebrates use non-spawning habitats as refugia in streams. Our study explored how the spatial and temporal distribution of macroinvertebrates changed during a pink salmon (Oncorhynchus gorbuscha) spawning run and compared macroinvertebrates in spawning (riffle) and non-spawning (refugia) habitats in an Alaskan stream. Potential refugia included: pools, stream margins and the hyporheic zone, and we also sampled invertebrate drift. We predicted that macroinvertebrates would decline in riffles and increase in drift and refugia habitats during salmon spawning. We observed a reduction in the density, biomass and taxonomic richness of macroinvertebrates in riffles during spawning. There was no change in pool and margin invertebrate communities, except insect biomass declined in pools during the spawning period. Macroinvertebrate density was greater in the hyporheic zone and macroinvertebrate density and richness increased in the drift during spawning. We observed significant invertebrate declines within spawning habitat; however in non-spawning habitat, there were less pronounced changes in invertebrate density and richness. The results observed may be due to spawning-related disturbances, insect phenology, or other variables. We propose that certain in-stream habitats could be important for the persistence of macroinvertebrates during salmon spawning in a Southeast Alaskan stream.

  4. Predator avoidance during reproduction: diel movements by spawning sockeye salmon between stream and lake habitats.

    Science.gov (United States)

    Bentley, Kale T; Schindler, Daniel E; Cline, Timothy J; Armstrong, Jonathan B; Macias, Daniel; Ciepiela, Lindsy R; Hilborn, Ray

    2014-11-01

    enough to spawn. Given the interannual variation in the timing and intensity of predation pressure, the advantages of a particular movement strategy will likely vary among years. Regardless, movements by salmon allowed individuals to exploit fine-scale habitat heterogeneity during reproduction, which appears to be a strategy to reduce predation risk on the spawning grounds. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

  5. Identification of the Spawning, Rearing, and Migratory Requirements of Fall Chinook Salmon in the Columbia River Basin, Annual Report 1994.

    Energy Technology Data Exchange (ETDEWEB)

    Rondorf, Dennis W.; Tiffan, Kenneth F.

    1996-08-01

    Spawning ground surveys were conducted in 1994 as part of a five year study of Snake River chinook salmon Oncorhynchus tshawyacha begun in 1991. Observations of fall chinook salmon spawning in the Snake River were limited to infrequent aerial red counts in the years prior to 1987. From 1987-1990, red counts were made on a limited basis by an interagency team and reported by the Washington Department of Fisheries. Starting in 1991, the U.S. Fish and Wildlife Service (USFWS), and other cooperating agencies and organizations, expanded the scope of spawning ground surveys to include: (1) additional aerial surveys to improve red counts and provide data on the timing of spawning; (2) the validation (ground truthing) of red counts from aerial surveys to improve count accuracy; (3) underwater searches to locate reds in water too deep to allow detection from the air; and (4) bathymetric mapping of spawning sites for characterizing spawning habitat. This document is the 1994 annual progress report for selected studies of fall chinook salmon. The studies were undertaken because of the growing concern about the declining salmon population in the Snake River basin.

  6. Evaluation of Salmon Spawning below the Four Lowermost Columbia River Dams, 2004-2005 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Geist, David; Currie, Andrea [Pacific Northwest National Laboratory

    2006-02-01

    Since FY 2000, scientists at Pacific Northwest National Laboratory (PNNL) have conducted research to assess the extent of spawning by chum (Oncorhynchus keta) and fall Chinook (O. tshawytscha) salmon in the lower mainstem Columbia River. Their work supports a larger Bonneville Power Administration (BPA) project aimed at characterizing the physical habitat used by mainstem fall Chinook and chum salmon populations. Multiple collaborators in addition to PNNL are involved in the BPA project--counterparts include the Washington Department of Fish and Wildlife (WDFW), U.S. Fish and Wildlife Service (USFWS), Pacific States Marine Fisheries Commission (PSMFC), U.S. Geological Survey (USGS), and Oregon Department of Fish and Wildlife (ODFW). Data resulting from the individual tasks each agency conducts are providing a sound scientific basis for developing strategies to operate the Federal Columbia River Power System (FCRPS) in ways that will effectively protect and enhance the chum and fall Chinook salmon populations--both listed as threatened under the Endangered Species Act. Fall Chinook salmon, thought to originate from Bonneville Hatchery, were first noted to be spawning downstream of Bonneville Dam by biologists from the WDFW in 1993. Known spawning areas include gravel beds on the Washington side of the river near Hamilton Creek and Ives Island. Limited spawning ground surveys were conducted in the area around Ives and Pierce islands during 1994 through 1997. Based on these surveys, fall Chinook salmon were believed to be spawning successfully in this area. In addition, chum salmon have been documented spawning downstream of Bonneville Dam. In FY 1999, BPA Project No. 1999-003 was initiated by the WDFW, ODFW, and the USFWS to characterize the variables associated with physical habitat used by mainstem fall Chinook and chum salmon populations and to better understand the effects of hydropower project operations on spawning and incubation. Pacific Northwest National

  7. Evaluation of Fall Chinook and Chum Salmon Spawning below Bonneville Dam; 2004-2005 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    van der Naald, Wayne; Duff, Cameron; Friesen, Thomas A. (Oregon Department of Fish and Wildlife, Clackamas, OR)

    2006-02-01

    Pacific salmon Oncorhynchus spp. populations have declined over the last century due to a variety of human impacts. Chum salmon O. keta populations in the Columbia River have remained severely depressed for the past several decades, while upriver bright (URB) fall Chinook salmon O. tschawytscha populations have maintained relatively healthy levels. For the past seven years we have collected data on adult spawning and juvenile emergence and outmigration of URB fall Chinook and chum salmon populations in the Ives and Pierce islands complex below Bonneville Dam. In 2004, we estimated 1,733 fall Chinook salmon and 336 chum salmon spawned in our study area. Fall Chinook salmon spawning peaked 19 November with 337 redds and chum salmon spawning peaked 3 December with 148 redds. Biological characteristics continue to suggest chum salmon in our study area are similar to nearby stocks in Hardy and Hamilton creeks, and Chinook salmon we observe are similar to upriver bright stocks. Temperature data indicated that 2004 brood URB fall Chinook salmon emergence began on 6 January and ended 27 May 2005, with peak emergence occurring 12 March. Chum salmon emergence began 4 February and continued through 2 May 2005, with peak emergence occurring on 21 March. Between 13 January and 28 June, we sampled 28,984 juvenile Chinook salmon and 1,909 juvenile chum salmon. We also released 32,642 fin-marked and coded-wire tagged juvenile fall Chinook salmon to assess survival. The peak catch of juvenile fall Chinook salmon occurred on 18 April. Our results suggested that the majority of fall Chinook salmon outmigrate during late May and early June, at 70-80 mm fork length (FL). The peak catch of juvenile chum salmon occurred 25 March. Juvenile chum salmon appeared to outmigrate at 40-55 mm FL. Outmigration of chum salmon peaked in March but extended into April and May.

  8. Distribution, persistence, and hydrologic characteristics of salmon spawning habitats in clearwater side channels of the Matanuska River, southcentral Alaska

    Science.gov (United States)

    Curran, Janet H.; McTeague, Monica L.; Burril, Sean E.; Zimmerman, Christian E.

    2011-01-01

    Turbid, glacially influenced rivers are often considered to be poor salmon spawning and rearing habitats and, consequently, little is known about salmon habitats that do occur within rivers of this type. To better understand salmon spawning habitats in the Matanuska River of southcentral Alaska, the distribution and characteristics of clearwater side-channel spawning habitats were determined and compared to spawning habitats in tributaries. More than 100 kilometers of clearwater side channels within the braided mainstem of the Matanuska River were mapped for 2006 from aerial images and ground-based surveys. In reaches selected for historical analysis, side channel locations shifted appreciably between 1949 and 2006, but the relative abundance of clearwater side channels was fairly stable during the same period. Geospatial analysis of side channel distribution shows side channels typically positioned along abandoned bars at the braid plain margin rather than on bars between mainstem channels, and shows a strong correlation of channel abundance with braid plain width. Physical and geomorphic characteristics of the channel and chemical character of the water measured at 19 side channel sites, 6 tributary sites, 4 spring sites, and 5 mainstem channel sites showed conditions suitable for salmon spawning in side channels and tributaries, and a correlation of side channel characteristics with the respective tributary or groundwater source water. Autumn-through-spring monitoring of intergravel water temperatures adjacent to salmon redds (nests) in three side channels and two tributaries indicate adequate accumulated thermal units for incubation and emergence of salmon in side channels and relatively low accumulated thermal units in tributaries.

  9. Salmon returns and consumer fitness: growth and energy storage in stream-dwelling salmonids increases with spawning salmon abundance

    Science.gov (United States)

    We examined how biomass of marine-derived nutrients (MDN), in the form of spawning Pacific salmon, influenced the nutritional status and nitrogen stable isotope ratios (d15N) of stream-dwelling fishes. We sampled coho salmon (Oncorhynchus kisutch) parr and juvenile Dolly Varden (Salvelinus malma) d...

  10. AFSC/ABL: Stock composition, timing, and spawning distribution of Yukon River Chinook salmon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Radio telemetry was used to determine the distribution, locate spawning sites, and evaluate the tagging response of wild Chinook salmon Oncorhynchus tshawytscha...

  11. Transcriptomics of environmental acclimatization and survival in wild adult Pacific sockeye salmon (Oncorhynchus nerka) during spawning migration.

    Science.gov (United States)

    Evans, Tyler G; Hammill, Edd; Kaukinen, Karia; Schulze, Angela D; Patterson, David A; English, Karl K; Curtis, Janelle M R; Miller, Kristina M

    2011-11-01

    Environmental shifts accompanying salmon spawning migrations from ocean feeding grounds to natal freshwater streams can be severe, with the underlying stress often cited as a cause of increased mortality. Here, a salmonid microarray was used to characterize changes in gene expression occurring between ocean and river habitats in gill and liver tissues of wild migrating sockeye salmon (Oncorhynchus nerka Walbaum) returning to spawn in the Fraser River, British Columbia, Canada. Expression profiles indicate that the transcriptome of migrating salmon is strongly affected by shifting abiotic and biotic conditions encountered along migration routes. Conspicuous shifts in gene expression associated with changing salinity, temperature, pathogen exposure and dissolved oxygen indicate that these environmental variables most strongly impact physiology during spawning migrations. Notably, transcriptional changes related to osmoregulation were largely preparatory and occurred well before salmon encountered freshwater. In the river environment, differential expression of genes linked with elevated temperatures indicated that thermal regimes within the Fraser River are approaching tolerance limits for adult salmon. To empirically correlate gene expression with survival, biopsy sampling of gill tissue and transcriptomic profiling were combined with telemetry. Many genes correlated with environmental variables were differentially expressed between premature mortalities and successful migrants. Parametric survival analyses demonstrated a broad-scale transcriptional regulator, cofactor required for Sp1 transcriptional activation (CRSP), to be significantly predictive of survival. As the environmental characteristics of salmon habitats continue to change, establishing how current environmental conditions influence salmon physiology under natural conditions is critical to conserving this ecologically and economically important fish species. © 2011 Blackwell Publishing Ltd.

  12. Effects of habitat quality and ambient hyporheic flows on salmon spawning site selection

    Science.gov (United States)

    Rohan Benjankar; Daniele Tonina; Alessandra Marzadri; Jim McKean; Daniel J. Isaak

    2016-01-01

    Understanding the role of stream hydrologic and morphologic variables on the selection of spawning sites by salmonid fishes at high resolution across broad scales is needed for effective habitat restoration and protection. Here we used remotely sensed meter-scale channel bathymetry for a 13.5 km reach of Chinook salmon spawning stream in central Idaho to...

  13. Spawning distribution of fall chinook salmon in the Snake River : annual report 1998.; ANNUAL

    International Nuclear Information System (INIS)

    Garcia, Aaron P.

    1999-01-01

    In 1998 data was collected on the spawning distribution of the first adult fall chinook salmon to return from releases of yearling hatchery fish upriver of Lower Granite Dam. Yearling fish were released at three locations with the intent of distributing spawning throughout the existing habitat. The project was designed to use radio-telemetry to determine if the use of multiple release sites resulted in widespread spawning

  14. Inventory and Mapping of Sixmile Lakes Sockeye Salmon Spawning Habitat

    National Research Council Canada - National Science Library

    Gotthardt, Tracey

    2002-01-01

    .... The purpose of this project is to provide baseline inventory information on sockeye spawning habitat which may be used to determine the carrying capacity of spawning in this drainage, to plan future...

  15. A probabilistic approach to quantifying hydrologic thresholds regulating migration of adult Atlantic salmon into spawning streams

    Science.gov (United States)

    Lazzaro, G.; Soulsby, C.; Tetzlaff, D.; Botter, G.

    2017-03-01

    Atlantic salmon is an economically and ecologically important fish species, whose survival is dependent on successful spawning in headwater rivers. Streamflow dynamics often have a strong control on spawning because fish require sufficiently high discharges to move upriver and enter spawning streams. However, these streamflow effects are modulated by biological factors such as the number and the timing of returning fish in relation to the annual spawning window in the fall/winter. In this paper, we develop and apply a novel probabilistic approach to quantify these interactions using a parsimonious outflux-influx model linking the number of female salmon emigrating (i.e., outflux) and returning (i.e., influx) to a spawning stream in Scotland. The model explicitly accounts for the interannual variability of the hydrologic regime and the hydrological connectivity of spawning streams to main rivers. Model results are evaluated against a detailed long-term (40 years) hydroecological data set that includes annual fluxes of salmon, allowing us to explicitly assess the role of discharge variability. The satisfactory model results show quantitatively that hydrologic variability contributes to the observed dynamics of salmon returns, with a good correlation between the positive (negative) peaks in the immigration data set and the exceedance (nonexceedance) probability of a threshold flow (0.3 m3/s). Importantly, model performance deteriorates when the interannual variability of flow regime is disregarded. The analysis suggests that flow thresholds and hydrological connectivity for spawning return represent a quantifiable and predictable feature of salmon rivers, which may be helpful in decision making where flow regimes are altered by water abstractions.

  16. Spawning Habitat Studies of Hanford Reach Fall Chinook Salmon (Oncorhynchus tshawytscha), Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Geist, David R.; Arntzen, Evan V.; Chien, Yi-Ju (Pacific Northwest National Laboratory)

    2009-03-02

    The Pacific Northwest National Laboratory conducted this study for the Bonneville Power Administration (BPA) with funding provided through the Northwest Power and Conservation Council(a) and the BPA Fish and Wildlife Program. The study was conducted in the Hanford Reach of the Columbia River. The goal of study was to determine the physical habitat factors necessary to define the redd capacity of fall Chinook salmon that spawn in large mainstem rivers like the Hanford Reach and Snake River. The study was originally commissioned in FY 1994 and then recommissioned in FY 2000 through the Fish and Wildlife Program rolling review of the Columbia River Basin projects. The work described in this report covers the period from 1994 through 2004; however, the majority of the information comes from the last four years of the study (2000 through 2004). Results from the work conducted from 1994 to 2000 were covered in an earlier report. More than any other stock of Pacific salmon, fall Chinook salmon (Oncorhynchus tshawytscha) have suffered severe impacts from the hydroelectric development in the Columbia River Basin. Fall Chinook salmon rely heavily on mainstem habitats for all phases of their life cycle, and mainstem hydroelectric dams have inundated or blocked areas that were historically used for spawning and rearing. The natural flow pattern that existed in the historic period has been altered by the dams, which in turn have affected the physical and biological template upon which fall Chinook salmon depend upon for successful reproduction. Operation of the dams to produce power to meet short-term needs in electricity (termed power peaking) produces unnatural fluctuations in flow over a 24-hour cycle. These flow fluctuations alter the physical habitat and disrupt the cues that salmon use to select spawning sites, as well as strand fish in near-shore habitat that becomes dewatered. The quality of spawning gravels has been affected by dam construction, flood protection, and

  17. Genetic characterization of naturally spawned Snake River fall-run Chinook salmon

    Science.gov (United States)

    Marshall, A.R.; Blankenship, H.L.; Connor, W.P.

    1999-01-01

    We sampled juvenile Snake River chinook salmon Oncorhynchus tshawytscha to genetically characterize the endangered Snake River fall-run population. Juveniles from fall and spring–summer lineages coexisted in our sampling areas but were differentiated by large allozyme allele frequency differences. We sorted juveniles by multilocus genotypes into putative fall and spring lineage subsamples and determined lineage composition using maximum likelihood estimation methods. Paired sMEP-1* and PGK-2* genotypes—encoding malic enzyme (NADP+) and phosphoglycerate kinase, respectively—were very effective for sorting juveniles by lineage, and subsamples estimated to be 100% fall lineage were obtained in four annual samples. We examined genetic relationships of these fall lineage juveniles with adjacent populations from the Columbia River and from Lyons Ferry Hatchery, which was established to perpetuate the Snake River fall-run population. Our samples of naturally produced Snake River fall lineage juveniles were most closely aligned with Lyons Ferry Hatchery samples. Although fall-run strays of Columbia River hatchery origin found on spawning grounds threaten the genetic integrity of the Snake River population, juvenile samples (a) showed distinctive patterns of allelic diversity, (b) were differentiated from Columbia River populations, and (c) substantiate earlier conclusions that this population is an important genetic resource. This first characterization of naturally produced Snake River fall chinook salmon provides a baseline for monitoring and recovery planning.

  18. Spawning data - Snake River sockeye salmon captive propagation

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gene rescue captive broodstock program was established for ESA-listed endangered Snake River sockeye salmon from Redfish Lake, Idaho. The program has consisted of...

  19. Evaluate the Restoration Potential of Snake River Fall Chinook Salmon Spawning Habitat, Status Report 2006.

    Energy Technology Data Exchange (ETDEWEB)

    Hanrahan, T.P. [Pacific Northwest National Laboratory

    2009-01-08

    The Bonneville Power Administration (BPA) Project 2003-038-00, Evaluate the restoration potential of Snake River fall Chinook salmon spawning habitat, began in FY04 (15 December 2003) and continues into FY06. This status report is intended to summarize accomplishments during FY04 and FY05. Accomplishments are summarized by Work Elements, as detailed in the Statement of Work (see BPA's project management database PISCES). This project evaluates the restoration potential of mainstem habitats for fall Chinook salmon. The studies address two research questions: 'Are there sections not currently used by spawning fall Chinook salmon within the impounded lower Snake River that possess the physical characteristics for potentially suitable fall Chinook spawning habitat?' and 'Can hydrosystem operations affecting these sections be adjusted such that the sections closely resemble the physical characteristics of current fall Chinook salmon spawning areas in similar physical settings?' Efforts are focused at two study sites: (1) the Ice Harbor Dam tailrace downstream to the Columbia River confluence, and (2) the Lower Granite Dam tailrace. Our previous studies indicated that these two areas have the highest potential for restoring Snake River fall Chinook salmon spawning habitat. The study sites will be evaluated under existing structural configurations at the dams (i.e., without partial removal of a dam structure), and alternative operational scenarios (e.g., varying forebay/tailwater elevations). The areas studied represent tailwater habitat (i.e., riverine segments extending from a dam downstream to the backwater influence from the next dam downstream). We are using a reference site, indicative of current fall Chinook salmon spawning areas in tailwater habitat, against which to compare the physical characteristics of each study site. The reference site for tailwater habitats is the section extending downstream from the Wanapum Dam tailrace on the

  20. Tradeoffs between homing and habitat quality for spawning site selection by hatchery-origin Chinook salmon

    Science.gov (United States)

    Cram, Jeremy M.; Torgersen, Christian E.; Klett, Ryan S.; Pess, George R.; May, Darran; Pearsons, Todd N.; Dittman, Andrew H.

    2013-01-01

    Spawning site selection by female salmon is based on complex and poorly understood tradeoffs between the homing instinct and the availability of appropriate habitat for successful reproduction. Previous studies have shown that hatchery-origin Chinook salmon (Oncorhynchus tshawytscha) released from different acclimation sites return with varying degrees of fidelity to these areas. To investigate the possibility that homing fidelity is associated with aquatic habitat conditions, we quantified physical habitat throughout 165 km in the upper Yakima River basin (Washington, USA) and mapped redd and carcass locations from 2004 to 2008. Principal components analysis identified differences in substrate, cover, stream width, and gradient among reaches surrounding acclimation sites, and canonical correspondence analysis revealed that these differences in habitat characteristics were associated with spatial patterns of spawning (p < 0.01). These analyses indicated that female salmon may forego spawning near their acclimation area if the surrounding habitat is unsuitable. Evaluating the spatial context of acclimation areas in relation to surrounding habitat may provide essential information for effectively managing supplementation programs and prioritizing restoration actions.

  1. Rearing in seawater mesocosms improves the spawning performance of growth hormone transgenic and wild-type coho salmon.

    Directory of Open Access Journals (Sweden)

    Rosalind A Leggatt

    Full Text Available Growth hormone (GH transgenes can significantly accelerate growth rates in fish and cause associated alterations to their physiology and behaviour. Concern exists regarding potential environmental risks of GH transgenic fish, should they enter natural ecosystems. In particular, whether they can reproduce and generate viable offspring under natural conditions is poorly understood. In previous studies, GH transgenic salmon grown under contained culture conditions had lower spawning behaviour and reproductive success relative to wild-type fish reared in nature. However, wild-type salmon cultured in equal conditions also had limited reproductive success. As such, whether decreased reproductive success of GH transgenic salmon is due to the action of the transgene or to secondary effects of culture (or a combination has not been fully ascertained. Hence, salmon were reared in large (350,000 L, semi-natural, seawater tanks (termed mesocosms designed to minimize effects of standard laboratory culture conditions, and the reproductive success of wild-type and GH transgenic coho salmon from mesocosms were compared with that of wild-type fish from nature. Mesocosm rearing partially restored spawning behaviour and success of wild-type fish relative to culture rearing, but remained lower overall than those reared in nature. GH transgenic salmon reared in the mesocosm had similar spawning behaviour and success as wild-type fish reared in the mesocosm when in full competition and without competition, but had lower success in male-only competition experiments. There was evidence of genotype×environmental interactions on spawning success, so that spawning success of transgenic fish, should they escape to natural systems in early life, cannot be predicted with low uncertainty. Under the present conditions, we found no evidence to support enhanced mating capabilities of GH transgenic coho salmon compared to wild-type salmon. However, it is clear that GH transgenic

  2. A spatial model to assess the effects of hydropower operations on Columbia River fall Chinook Salmon spawning habitat

    Science.gov (United States)

    Hatten, James R.; Tiffan, Kenneth F.; Anglin, Donald R.; Haeseker, Steven L.; Skalicky, Joseph J.; Schaller, Howard

    2009-01-01

    Priest Rapids Dam on the Columbia River produces large daily and hourly streamflow fluctuations throughout the Hanford Reach during the period when fall Chinook salmon Oncorhynchus tshawytscha are selecting spawning habitat, constructing redds, and actively engaged in spawning. Concern over the detrimental effects of these fluctuations prompted us to quantify the effects of variable flows on the amount and persistence of fall Chinook salmon spawning habitat in the Hanford Reach. Specifically, our goal was to develop a management tool capable of quantifying the effects of current and alternative hydrographs on predicted spawning habitat in a spatially explicit manner. Toward this goal, we modeled the water velocities and depths that fall Chinook salmon experienced during the 2004 spawning season, plus what they would probably have experienced under several alternative (i.e., synthetic) hydrographs, using both one- and two-dimensional hydrodynamic models. To estimate spawning habitat under existing or alternative hydrographs, we used cell-based modeling and logistic regression to construct and compare numerous spatial habitat models. We found that fall Chinook salmon were more likely to spawn at locations where velocities were persistently greater than 1 m/s and in areas where fluctuating water velocities were reduced. Simulations of alternative dam operations indicate that the quantity of spawning habitat is expected to increase as streamflow fluctuations are reduced during the spawning season. The spatial habitat models that we developed provide management agencies with a quantitative tool for predicting, in a spatially explicit manner, the effects of different flow regimes on fall Chinook salmon spawning habitat in the Hanford Reach. In addition to characterizing temporally varying habitat conditions, our research describes an analytical approach that could be applied in other highly variable aquatic systems.

  3. Do Spawning Salmon Contribute Marine-Derived Contaminants to Southeast Alaskan Streams?

    Science.gov (United States)

    Nagorski, S. A.; Hudson, J. P.; Fellman, J.; Hood, E. W.; Vermilyea, A.; Krabbenhoft, D. P.; Ylitalo, G.

    2016-12-01

    Pacific salmon are well known contributors of marine-derived nutrients and carbon to freshwater systems where they spawn and die. A potentially negative side effect of their freshwater spawning legacy is their additional contribution of pollutants accumulated during the marine phase of their life cycle. Alaskan salmon, which undergo the majority of their bodily growth in the North Pacific, are being exposed to rising concentrations of pollutants in the waters and foodwebs of the north Pacific. In this study we investigated the contribution of mercury and persistent organic pollutants (POPs) by spawning Pacific salmon to five streams in the vicinity of Juneau, Alaska. Using a nested experimental design inherent in streams with natural migration barriers or steep density gradients, we collected samples from stream reaches with and without spawning salmon. We measured total and methyl mercury in filtered water, suspended particulates, streambed sediment, biofilm on incubated leaf packs, two taxa of benthic macroinvertebrate larvae, and rearing and/or resident fishes. The benthic macroinvertebrates and fishes were also analyzed for a suite of POPs, consisting of historic and current use pesticides and historic and urban use chemicals. For most parameters, contaminant concentrations were higher in the lower reaches where salmon spawners were present, with stronger effects in the streams with higher spawner densities. For example, in the two streams with the highest spawner densities, filtered methylmercury was an order of magnitude higher in the lower stream reach and comprised up to 33% of the total mercury. Alder leaf packs resulted in particularly consistent spatial patterns, while benthic macroinvertebrate larvae results were the least spatially consistent for both mercury and POPs. Although fish tissue mercury concentrations were not uniformly higher in lower stream reaches across our 5 study streams due to upstream sources of mercury and different fish species and

  4. Comparative mapping reveals quantitative trait loci that affect spawning time in coho salmon (Oncorhynchus kisutch

    Directory of Open Access Journals (Sweden)

    Cristian Araneda

    2012-01-01

    Full Text Available Spawning time in salmonids is a sex-limited quantitative trait that can be modified by selection. In rainbow trout (Oncorhynchus mykiss, various quantitative trait loci (QTL that affect the expression of this trait have been discovered. In this study, we describe four microsatellite loci associated with two possible spawning time QTL regions in coho salmon (Oncorhynchus kisutch. The four loci were identified in females from two populations (early and late spawners produced by divergent selection from the same base population. Three of the loci (OmyFGT34TUF, One2ASC and One19ASC that were strongly associated with spawning time in coho salmon (p < 0.0002 were previously associated with QTL for the same trait in rainbow trout; a fourth loci (Oki10 with a suggestive association (p = 0.00035 mapped 10 cM from locus OmyFGT34TUF in rainbow trout. The changes in allelic frequency observed after three generations of selection were greater than expected because of genetic drift. This work shows that comparing information from closely-related species is a valid strategy for identifying QTLs for marker-assisted selection in species whose genomes are poorly characterized or lack a saturated genetic map.

  5. Identification of the Spawning, Rearing and Migratory Requirements of Fall Chinook Salmon in the Columbia River Basin, Annual Report 1992.

    Energy Technology Data Exchange (ETDEWEB)

    Rondorf, Dennis W.; Miller, William H.

    1994-03-01

    This document is the 1992 annual progress report for selected studies of fall chinook Salmon Oncorhynchus tshawytscha conducted by the National Biological Survey (NBS) and the US Fish and Wildlife Service. The decline in abundance of fall chinook salmon in the Snake River basin has become a growing concern. Effective recovery efforts for fall chinook salmon cannot be developed until we increase our knowledge of the factors that are limiting the various life history stages. This study attempts to identify those physical and biological factors which influence spawning of fall chinook salmon in the free-flowing Snake River and their rearing and seaward migration through Columbia River basin reservoirs.

  6. Factors affecting the within-river spawning migration of Atlantic salmon, with emphasis on human impacts

    DEFF Research Database (Denmark)

    Thorstad, E.B.; Okland, F.; Aarestrup, Kim

    2008-01-01

    experience, water discharge, water temperature, water velocity, required jump heights, fish size, fish acclimatisation, light, water quality/pollution, time of the season, and catch and handling stress. How each of these factors affects the upstream migration is to a varying extent understood; however......We review factors affecting the within-river spawning migration of Atlantic salmon. With populations declining across the entire distribution range, it is important that spawners survive in the last phase of the spawning migration. Knowledge on the factors affecting migration is essential...... be delayed at natural migration barriers. Often, the magnitude of delay is not predictable; fish may be considerably delayed at barriers that appear to humans to be easily passable, or they may quickly pass barriers that appear difficult. Stressful events like catch-and-release angling may affect upstream...

  7. Spawning salmon disrupt trophic coupling between wolves and ungulate prey in coastal British Columbia

    Directory of Open Access Journals (Sweden)

    Darimont Chris T

    2008-09-01

    Full Text Available Abstract Background As a cross-boundary resource subsidy, spawning salmon can strongly affect consumer and ecosystem ecology. Here we examine whether this marine resource can influence a terrestrial wolf-deer (Canis lupus-Odocoileus hemionus predator-prey system in coastal British Columbia, Canada. Data on resource availability and resource use among eight wolf groups for three seasons over four years allow us to evaluate competing hypotheses that describe salmon as either an alternate resource, consumed in areas where deer are scarce, or as a targeted resource, consumed as a positive function of its availability. Faecal (n = 2203 wolf scats and isotopic analyses (n = 60 wolf hair samples provide independent data sets, also allowing us to examine how consistent these common techniques are in estimating foraging behaviour. Results At the population level during spring and summer, deer remains occurred in roughly 90 and 95% of faeces respectively. When salmon become available in autumn, however, the population showed a pronounced dietary shift in which deer consumption among groups was negatively correlated (r = -0.77, P 13C isotopic signatures (r = 0.78; P = 0.008, which were calculated by intra-hair comparisons between segments grown during summer and fall. The magnitude of this seasonal isotopic shift, our proxy for salmon use, was related primarily to estimates of salmon availability, not deer availability, among wolf groups. Conclusion Concordance of faecal and isotopic data suggests our intra-hair isotopic methodology provides an accurate proxy for salmon consumption, and might reliably track seasonal dietary shifts in other consumer-resource systems. Use of salmon by wolves as a function of its abundance and the adaptive explanations we provide suggest a long-term and widespread association between wolves and salmon. Seasonally, this system departs from the common wolf-ungulate model. Broad ecological implications include the potential

  8. Spawning and abundance of fall chinook salmon (Oncorhynchus tshawytscha) in the Hanford Reach of the Columbia River, 1948--1988

    Energy Technology Data Exchange (ETDEWEB)

    Dauble, D.D.; Watson, D.G.

    1990-03-01

    The Hanford Reach of the Columbia River provides the only major spawning habitat for the upriver bright (URB) race of fall chinook salmon in the mainstem Columbia River. Hanford Site biologists have conducted aerial surveys of spawning salmon in the Hanford Reach since 1948. This report summarizes data on fall chinook salmon spawning in the Hanford Reach and presents a discussion of factors that may affect population trends. Most data are limited to fisheries agency reports and other working documents. Fisheries management practices in the Columbia River system have changed rapidly over the last decade, particularly under requirements of the Pacific Northwest Power Planning and Conservation Act of 1980. New information has been generated and included in this report. 75 refs., 17 figs., 11 tabs.

  9. Identification of the Spawning, Rearing, and Migratory Requirements of Fall Chinook Salmon in the Columbia River Basin, Annual Report 1993.

    Energy Technology Data Exchange (ETDEWEB)

    Rondorf, Dennis W.; Tiffan, Kenneth F.

    1994-12-01

    Recovery efforts for the endangered fall chinook salmon necessitates knowledge of the factors limiting the various life history stages. This study attempts to identify those physical and biological factors which affect spawning of the fish in the free-flowing Snake River and their rearing seward migration through Columbia River basin reservoirs. The spawning was generally a November event in 1993, with some activity in late Oct. and early Dec. Spawning habitat availability was assessed by applying hydraulic and habitat models to known fall chinook salmon spawning sites. Juveniles were seined and PIT tagged in the free-flowing Snake River, and in the Columbia River in he Hanford Reach and in McNary Reservoir. Subyearling fish were marked at McNary Dam to relate river flow and migration patterns of juveniles to adult returns. Hydroacoustic surveys were conducted on McNary and John Day reservoirs and in net pens.

  10. Total Dissolved Gas Monitoring in Chum Salmon Spawning Gravels Below Bonneville Dam

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, Evan V.; Geist, David R.; Panther, Jennifer L.; Dawley, Earl

    2007-01-30

    At the request of the U.S. Army Corps of Engineers (Portland District), Pacific Northwest National Laboratory (PNNL) conducted research to determine whether total dissolved gas concentrations are elevated in chum salmon redds during spring spill operations at Bonneville Dam. The study involved monitoring the total dissolved gas levels at egg pocket depth and in the river at two chum salmon spawning locations downstream from Bonneville Dam. Dissolved atmospheric gas supersaturation generated by spill from Bonneville Dam may diminish survival of chum (Oncorhynchus keta) salmon when sac fry are still present in the gravel downstream from Bonneville Dam. However, no previous work has been conducted to determine whether total dissolved gas (TDG) levels are elevated during spring spill operations within incubation habitats. The guidance used by hydropower system managers to provide protection for pre-emergent chum salmon fry has been to limit TDG to 105% after allowing for depth compensation. A previous literature review completed in early 2006 shows that TDG levels as low as 103% have been documented to cause mortality in sac fry. Our study measured TDG in the incubation environment to evaluate whether these levels were exceeded during spring spill operations. Total dissolved gas levels were measured within chum salmon spawning areas near Ives Island and Multnomah Falls on the Columbia River. Water quality sensors screened at egg pocket depth and to the river were installed at both sites. At each location, we also measured dissolved oxygen, temperature, specific conductance, and water depth to assist with the interpretation of TDG results. Total dissolved gas was depth-compensated to determine when levels were high enough to potentially affect sac fry. This report provides detailed descriptions of the two study sites downstream of Bonneville Dam, as well as the equipment and procedures employed to monitor the TDG levels at the study sites. Results of the monitoring at

  11. Redd Site Selection and Spawning Habitat Use by Fall Chinook Salmon, Hanford Reach, Columbia River : Final Report 1995 - 1998.

    Energy Technology Data Exchange (ETDEWEB)

    Geist, David R.

    1999-05-01

    This report summarizes results of research activities conducted from 1995 through 1998 on identifying the spawning habitat requirements of fall chinook salmon (Oncorhynchus tshawytscha) in the Hanford Reach of the Columbia River. The project investigated whether traditional spawning habitat models could be improved in order to make better predictions of available habitat for fall chinook salmon in the Snake River. Results suggest models could be improved if they used spawning area-specific, rather than river-specific, spawning characteristics; incorporated hyporheic discharge measurements; and gave further consideration to the geomorphic features that are present in the unconstrained segments of large alluvial rivers. Ultimately the recovery of endangered fall chinook salmon will depend on how well we are able to recreate the characteristics once common in alluvial floodplains of large rivers. The results from this research can be used to better define the relationship between these physical habitat characteristics and fall chinook salmon spawning site selection, and provide more efficient use of limited recovery resources. This report is divided into four chapters which were presented in the author's doctoral dissertation which he completed through the Department of Fisheries and Wildlife at Oregon State University. Each of the chapters has been published in peer reviewed journals or is currently under review. Chapter one is a conceptual spawning habitat model that describes how geomorphic features of river channels create hydraulic processes, including hyporheic flows, that influence where salmon spawn in unconstrained reaches of large mainstem alluvial rivers. Chapter two describes the comparison of the physical factors associated with fall chinook salmon redd clusters located at two sites within the Reach. Spatial point pattern analysis of redds showed that redd clusters averaged approximately 10 hectares in area and their locations were consistent from

  12. Evaluation of fall chinook salmon spawning adjacent to the In-Situ Redox Manipulation treatability test site, Hanford Site, Washington

    International Nuclear Information System (INIS)

    Mueller, R.P.; Geist, D.R.

    1998-10-01

    The In Situ Redox Manipulation (ISRM) experiment is being evaluated as a potential method to remove contaminants from groundwater adjacent to the Columbia River near the 100-D Area. The ISRM experiment involves using sodium dithionate (Na 2 O 6 S 2 ) to precipitate chromate from the groundwater. The treatment will likely create anoxic conditions in the groundwater down-gradient of the ISRM treatability test site; however, the spatial extent of this anoxic plume is not exactly known. Surveys were conducted in November 1997, following the peak spawning of fall chinook salmon. Aerial surveys documented 210 redds (spawning nests) near the downstream island in locations consistent with previous surveys. Neither aerial nor underwater surveys documented fall chinook spawning in the vicinity of the ISRM treatability test site. Based on measurements of depth, velocity, and substrate, less than 1% of the study area contained suitable fall chinook salmon spawning habitat, indicating low potential for fall chinook salmon to spawn in the vicinity of the ISRM experiment

  13. Prespawning migratory behaviour and spawning success of sea-ranched Atlantic salmon, Salmo salar L., in the River Gudenaa, Denmark

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Jepsen, Niels; Rasmusssen, Gorm

    2000-01-01

    The migratory behaviour of sea-ranched Atlantic salmon, Salmo salar L., was analysed by radio-telemetry in the River Gudenaa, Denmark. The main objectives were to: (1) estimate mortality of returning adults through the fjord; (2) observe rate of progression and migratory pattern in the fjord...... and river; and (3) record whether spawning occurs in the river. Forty-two returning salmon (19 males and 23 females of total body length from 60-97 cm) reared and released as smolts, were caught and equipped with external radio transmitters in the outer estuary of the River Gudenaa in 1994 and 1995...... of the spawning period. Eight were retrieved dead from the river during or after the spawning period; four with empty gonads assumed to be successful spawners, and four with intact gonads. In 1994, unsuccessful spawners (found dead with intact gonads) entered the river earlier and had a longer total migration...

  14. Prespawning migratory behaviour and spawning success of sea-ranched Atlantic salmon, Salmo salar L., in the River Gudenaa, Denmark

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Jepsen, Niels; Rasmusssen, Gorm

    2000-01-01

    The migratory behaviour of sea-ranched Atlantic salmon, Salmo salar L., was analysed by radio-telemetry in the River Gudenaa, Denmark. The main objectives were to: (1) estimate mortality of returning adults through the fjord; (2) observe rate of progression and migratory pattern in the fjord...... distance in the river compared to successful. spawners. This suggests that spawning success of sea-ranched salmon is associated with time of river entry and river migration length...... and river; and (3) record whether spawning occurs in the river. Forty-two returning salmon (19 males and 23 females of total body length from 60-97 cm) reared and released as smolts, were caught and equipped with external radio transmitters in the outer estuary of the River Gudenaa in 1994 and 1995...

  15. Streambed scour of salmon spawning habitat in a regulated river influenced by management of peak discharge

    Science.gov (United States)

    Gendaszek, Andrew S.; Burton, Karl D.; Magirl, Christopher S.; Konrad, Christopher P.

    2017-01-01

    In the Pacific Northwest of the United States, salmon eggs incubating within streambed gravels are susceptible to scour during floods. The threat to egg-to-fry survival by streambed scour is mitigated, in part, by the adaptation of salmon to bury their eggs below the typical depth of scour. In regulated rivers globally, we suggest that water managers consider the effect of dam operations on scour and its impacts on species dependent on benthic habitats.We instrumented salmon-spawning habitat with accelerometer scour monitors (ASMs) at 73 locations in 11 reaches of the Cedar River in western Washington State of the United States from Autumn 2013 through the Spring of 2014. The timing of scour was related to the discharge measured at a nearby gage and compared to previously published ASM data at 26 locations in two reaches of the Cedar River collected between Autumn 2010 and Spring 2011.Thirteen percent of the recovered ASMs recorded scour during a peak-discharge event in March 2014 (2-to 3-year recurrence interval) compared to 71% of the recovered ASMs during a higher peak-discharge event in January 2011 (10-year recurrence interval). Of the 23 locations where ASMs recorded scour during the 2011 and 2014 deployments, 35% had scour when the discharge was ≤87.3 m3/s (3,082 ft3/s) (2-year recurrence interval discharge) with 13% recording scour at or below the 62.3 m3/s (2,200 ft3/s) operational threshold for peak-discharge management during the incubation of salmon eggs.Scour to the depth of salmon egg pockets was limited during peak discharges with frequent (1.25-year or less) recurrence intervals, which managers can regulate through dam operations on the Cedar River. Pairing novel measurements of the timing of streambed scour with discharge data allows the development of peak-discharge management strategies that protect salmon eggs incubating within streambed gravels during floods.

  16. The role of density-dependent and -independent processes in spawning habitat selection by salmon in an Arctic riverscape.

    Directory of Open Access Journals (Sweden)

    Brock M Huntsman

    Full Text Available Density-dependent (DD and density-independent (DI habitat selection is strongly linked to a species' evolutionary history. Determining the relative importance of each is necessary because declining populations are not always the result of altered DI mechanisms but can often be the result of DD via a reduced carrying capacity. We developed spatially and temporally explicit models throughout the Chena River, Alaska to predict important DI mechanisms that influence Chinook salmon spawning success. We used resource-selection functions to predict suitable spawning habitat based on geomorphic characteristics, a semi-distributed water-and-energy balance hydrologic model to generate stream flow metrics, and modeled stream temperature as a function of climatic variables. Spawner counts were predicted throughout the core and periphery spawning sections of the Chena River from escapement estimates (DD and DI variables. Additionally, we used isodar analysis to identify whether spawners actively defend spawning habitat or follow an ideal free distribution along the riverscape. Aerial counts were best explained by escapement and reference to the core or periphery, while no models with DI variables were supported in the candidate set. Furthermore, isodar plots indicated habitat selection was best explained by ideal free distributions, although there was strong evidence for active defense of core spawning habitat. Our results are surprising, given salmon commonly defend spawning resources, and are likely due to competition occurring at finer spatial scales than addressed in this study.

  17. Population Estimates for Chum Salmon Spawning in the Mainstem Columbia River, 2002 Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Rawding, Dan; Hillson, Todd D. (Washington Department of Fish and Wildlife, Olympia, WA)

    2003-11-15

    Accurate and precise population estimates of chum salmon (Oncorhynchus keta) spawning in the mainstem Columbia River are needed to provide a basis for informed water allocation decisions, to determine the status of chum salmon listed under the Endangered Species Act, and to evaluate the contribution of the Duncan Creek re-introduction program to mainstem spawners. Currently, mark-recapture experiments using the Jolly-Seber model provide the only framework for this type of estimation. In 2002, a study was initiated to estimate mainstem Columbia River chum salmon populations using seining data collected while capturing broodstock as part of the Duncan Creek re-introduction. The five assumptions of the Jolly-Seber model were examined using hypothesis testing within a statistical framework, including goodness of fit tests and secondary experiments. We used POPAN 6, an integrated computer system for the analysis of capture-recapture data, to obtain maximum likelihood estimates of standard model parameters, derived estimates, and their precision. A more parsimonious final model was selected using Akaike Information Criteria. Final chum salmon escapement estimates and (standard error) from seining data for the Ives Island, Multnomah, and I-205 sites are 3,179 (150), 1,269 (216), and 3,468 (180), respectively. The Ives Island estimate is likely lower than the total escapement because only the largest two of four spawning sites were sampled. The accuracy and precision of these estimates would improve if seining was conducted twice per week instead of weekly, and by incorporating carcass recoveries into the analysis. Population estimates derived from seining mark-recapture data were compared to those obtained using the current mainstem Columbia River salmon escapement methodologies. The Jolly-Seber population estimate from carcass tagging in the Ives Island area was 4,232 adults with a standard error of 79. This population estimate appears reasonable and precise but batch

  18. Discovery of a spawning ground reveals diverse migration strategies in Atlantic bluefin tuna (Thunnus thynnus).

    Science.gov (United States)

    Richardson, David E; Marancik, Katrin E; Guyon, Jeffrey R; Lutcavage, Molly E; Galuardi, Benjamin; Lam, Chi Hin; Walsh, Harvey J; Wildes, Sharon; Yates, Douglas A; Hare, Jonathan A

    2016-03-22

    Atlantic bluefin tuna are a symbol of both the conflict between preservationist and utilitarian views of top ocean predators, and the struggle to reach international consensus on the management of migratory species. Currently, Atlantic bluefin tuna are managed as an early-maturing eastern stock, which spawns in the Mediterranean Sea, and a late-maturing western stock, which spawns in the Gulf of Mexico. However, electronic tagging studies show that many bluefin tuna, assumed to be of a mature size, do not visit either spawning ground during the spawning season. Whether these fish are spawning in an alternate location, skip-spawning, or not spawning until an older age affects how vulnerable this species is to anthropogenic stressors including exploitation. We use larval collections to demonstrate a bluefin tuna spawning ground in the Slope Sea, between the Gulf Stream and northeast United States continental shelf. We contend that western Atlantic bluefin tuna have a differential spawning migration, with larger individuals spawning in the Gulf of Mexico, and smaller individuals spawning in the Slope Sea. The current life history model, which assumes only Gulf of Mexico spawning, overestimates age at maturity for the western stock. Furthermore, individual tuna occupy both the Slope Sea and Mediterranean Sea in separate years, contrary to the prevailing view that individuals exhibit complete spawning-site fidelity. Overall, this complexity of spawning migrations questions whether there is complete independence in the dynamics of eastern and western Atlantic bluefin tuna and leads to lower estimates of the vulnerability of this species to exploitation and other anthropogenic stressors.

  19. Effects of hyporheic exchange flows on egg pocket water temperature in Snake River fall Chinook salmon spawning areas

    Energy Technology Data Exchange (ETDEWEB)

    Hanrahan, T. P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Geist, D. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Arntzen, E. V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Abernethy, C. S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2004-09-01

    The development of the Snake River hydroelectric system has affected fall Chinook salmon smolts by shifting their migration timing to a period (mid- to late-summer) when downstream reservoir conditions are unfavorable for survival. Subsequent to the Snake River Chinook salmon fall-run Evolutionary Significant Unit being listed as Threatened under the Endangered Species Act, recovery planning has included changes in hydrosystem operations (e.g., summer flow augmentation) to improve water temperature and flow conditions during the juvenile Chinook salmon summer migration period. In light of the limited water supplies from the Dworshak reservoir for summer flow augmentation, and the associated uncertainties regarding benefits to migrating fall Chinook salmon smolts, additional approaches for improved smolt survival need to be evaluated. This report describes research conducted by the Pacific Northwest National Laboratory (PNNL) that evaluated relationships among river discharge, hyporheic zone characteristics, and egg pocket water temperature in Snake River fall Chinook salmon spawning areas. This was a pilot-scale study to evaluate these relationships under existing operations of Hells Canyon Dam (i.e., without any prescribed manipulations of river discharge) during the 2002–2003 water year.

  20. Response of ecosystem metabolism to low densities of spawning Chinook salmon

    Science.gov (United States)

    Benjamin, Joseph R.; Bellmore, J. Ryan; Watson, Grace A.

    2016-01-01

    Marine derived nutrients delivered by large runs of returning salmon are thought to subsidize the in situ food resources that support juvenile salmon. In the Pacific Northwest, USA, salmon have declined to runs. We explored whether low densities (how recipient ecosystems respond to low levels of marine derived nutrients may inform nutrient augmentation studies aimed at enhancing fish populations.

  1. Movements of adult chinook salmon during spawning migration in a metals-contaminated system, Coeur d'Alene River, Idaho

    Science.gov (United States)

    Goldstein, J.N.; Woodward, D.F.; Farag, A.M.

    1999-01-01

    Spawning migration of adult male chinook salmon Oncorhynchus tshawytscha was monitored by radio telemetry to determine their response to the presence of metals contamination in the South Fork of the Coeur d'Alene River, Idaho. The North Fork of the Coeur d'Alene River is relatively free of metals contamination and was used as a control. In all, 45 chinook salmon were transported from their natal stream, Wolf Lodge Creek, tagged with radio transmitters, and released in the Coeur d'Alene River 2 km downstream of the confluence of the South Fork and the North Fork of the Coeur d'Alene River. Fixed telemetry receivers were used to monitor the upstream movement of the tagged chinook salmon through the confluence area for 3 weeks after release. During this period, general water quality and metals concentrations were monitored in the study area. Of the 23 chinook salmon observed to move upstream from the release site and through the confluence area, the majority (16 fish, 70%) moved up the North Fork, and only 7 fish (30%) moved up the South Fork, where greater metals concentrations were observed. Our results agree with laboratory findings and suggest that natural fish populations will avoid tributaries with high metals contamination.

  2. Variability in stream discharge and temperature: a preliminary assessment of the implications for juvenile and spawning Atlantic salmon

    Directory of Open Access Journals (Sweden)

    D. Tetzlaff

    2005-01-01

    Full Text Available This study focuses on understanding the temporal variability in hydrological and thermal conditions in a small mountain stream and its potential implication for two life stages of Atlantic salmon (Salmo salar – stream resident juveniles and returning adult spawners. Stream discharge and temperature in the Girnock Burn, NE Scotland, were characterised over ten hydrological years (1994/1995–2003/2004. Attention was focussed on assessing variations during particular ecologically 'sensitive' time periods when selected life-stages of salmon behaviour may be especially influenced by hydrological and thermal conditions. Empirical discharge data were used to derive hydraulic parameters to predict the Critical Displacement Velocity (CDV of juvenile salmon. This is the velocity above which fish may no longer be able to hold station in the water column and thus can be used as an index of time periods where feeding behaviour might be constrained. In the Girnock Burn, strong inter- and intra-annual variability in hydrological and thermal conditions may have important implications for feeding opportunities for juvenile fish; both during important growth periods in late winter and early spring, and the emergence of fry in the late spring. Time periods when foraging behaviour of juvenile salmon may be constrained by hydraulic conditions were assessed as the percentage time when CDV for 0+ and 1+ fish were exceeded by mean daily stream velocities. Clear seasonal patterns of CDV were apparent, with higher summer values driven by higher stream temperatures and fish length. Inter-annual variability in the time when mean stream velocity exceeded CDV for 0+ fish ranged between 29.3% (1997/1998 and 44.7% (2000/2001. For 1+ fish mean stream velocity exceeded CDV between 14.5% (1997/1998 and 30.7% (2000/2001 of the time. The movement of adult spawners into the Girnock Burn in preparation for autumn spawning (late October to mid-November exhibited a complex

  3. Using remotely sensed imagery and GIS to monitor and research salmon spawning: A case study of the Hanford Reach fall chinook (Oncorhynchus Tshawytscha)

    International Nuclear Information System (INIS)

    RH Visser

    2000-01-01

    The alteration of ecological systems has greatly reduced salmon populations in the Pacific Northwest. The Hanford Reach of the Columbia River, for example, is a component of the last ecosystem in eastern Washington State that supports a relatively healthy population of fall chinook salmon ([Oncorhynchus tshawytscha], Huntington et al. 1996). This population of fall chinook may function as a metapopulation for the Mid-Columbia region (ISG 1996). Metapopulations can seed or re-colonize unused habitat through the mechanism of straying (spawning in non-natal areas) and may be critical to the salmon recovery process if lost or degraded habitat is restored (i.e., the Snake, Upper Columbia, and Yakima rivers). For these reasons, the Hanford Reach fall chinook salmon population is extremely important for preservation of the species in the Columbia River Basin. Because this population is important to the region, non-intrusive techniques of analysis are essential for researching and monitoring population trends and spawning activities

  4. Concentrations of environmental DNA (eDNA) reflect spawning salmon abundance at fine spatial and temporal scales

    Science.gov (United States)

    Tillotson, Michael D.; Kelly, Ryan P.; Duda, Jeff; Hoy, Marshal S.; Kralj, James; Quinn, Thomas P.

    2018-01-01

    Developing fast, cost-effective assessments of wild animal abundance is an important goal for many researchers, and environmental DNA (eDNA) holds much promise for this purpose. However, the quantitative relationship between species abundance and the amount of DNA present in the environment is likely to vary substantially among taxa and with ecological context. Here, we report a strong quantitative relationship between eDNA concentration and the abundance of spawning sockeye salmon in a small stream in Alaska, USA, where we took temporally- and spatially-replicated samples during the spawning period. This high-resolution dataset suggests that (1) eDNA concentrations vary significantly day-to-day, and likely within hours, in the context of the dynamic biological event of a salmon spawning season; (2) eDNA, as detected by species-specific quantitative PCR probes, seems to be conserved over short distances (tens of meters) in running water, but degrade quickly over larger scales (ca. 1.5 km); and (3) factors other than the mere presence of live, individual fish — such as location within the stream, live/dead ratio, and water temperature — can affect the eDNA-biomass correlation in space or time. A multivariate model incorporating both biotic and abiotic variables accounted for over 75% of the eDNA variance observed, suggesting that where a system is well-characterized, it may be possible to predict species' abundance from eDNA surveys, although we underscore that species- and system-specific variables are likely to limit the generality of any given quantitative model. Nevertheless, these findings provide an important step toward quantitative applications of eDNA in conservation and management.

  5. Identification of the Spawning, Rearing, and Migratory Requirements of Fall Chinook Salmon in the Columbia River Basin, 1991 Annual Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Rondorf, Dennis W.; Miller, William H.

    1993-07-01

    This document is the 1991 annual progress report for selected studies of fall chinook salmon Oncorhynchus tshawytscha conducted by the US Fish and Wildlife Service. The decline in abundance of fall chinook salmon in the Snake River basin has become a growing concern. In April 1992, Snake River fall chinook salmon were listed as ``threatened`` under the Endangered Species Act. Effective recovery efforts for fall chinook salmon can not be developed until we increase our knowledge of the factors that are limiting the various life history stages. This study attempts to identify those physical and biological factors which influence spawning of fall chinook salmon in the free-flowing Snake River and their rearing and seaward migration through Columbia River basin reservoirs.

  6. Quantifying the Behavioral Response of Spawning Chum Salmon to Elevated Discharges from Bonneville Dam, Columbia River : Annual Report 2005-2006.

    Energy Technology Data Exchange (ETDEWEB)

    Tiffan, Kenneth F.; Haskell, Craig A.; Kock, Tobias J.

    2008-12-01

    In unimpounded rivers, Pacific salmon (Oncorhynchus spp.) typically spawn under relatively stable stream flows, with exceptions occurring during periodic precipitation events. In contrast, hydroelectric development has often resulted in an artificial hydrograph characterized by rapid changes in discharge and tailwater elevation that occur on a daily, or even an hourly basis, due to power generation (Cushman 1985; Moog 1993). Consequently, populations of Pacific salmon that are known to spawn in main-stem habitats below hydroelectric dams face the risks of changing habitat suitability, potential redd dewatering, and uncertain spawning success (Hamilton and Buell 1976; Chapman et al. 1986; Dauble et al. 1999; Garland et al. 2003; Connor and Pflug 2004; McMichael et al. 2005). Although the direct effects of a variable hydrograph, such as redd dewatering are apparent, specific effects on spawning behavior remain largely unexplored. Chum salmon (O. keta) that spawn below Bonneville Dam on the Columbia River are particularly vulnerable to the effects of water level fluctuations. Although chum salmon generally spawn in smaller tributaries (Johnson et al. 1997), many fish spawn in main-stem habitats below Bonneville Dam near Ives Island (Tomaro et al. 2007; Figure 1). The primary spawning area near Ives Island is shallow and sensitive to changes in water level caused by hydroelectric power generation at Bonneville Dam. In the past, fluctuating water levels have dewatered redds and changed the amount of available spawning habitat (Garland et al. 2003). To minimize these effects, fishery managers attempt to maintain a stable tailwater elevation at Bonneville Dam of 3.5 m (above mean sea level) during spawning, which ensures adequate water is provided to the primary chum salmon spawning area below the mouth of Hamilton Creek (Figure 1). Given the uncertainty of winter precipitation and water supply, this strategy has been effective at restricting spawning to a specific

  7. Evaluation of Fall Chinook and Chum Salmon Spawning below Bonneville, The Dalles, John Day and McNary Dams; 1999-2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    van der Naald, Wayne; Spellman, Bryant; Clark, Roy (Oregon Department of Fish and Wildlife, Portland, OR)

    2001-10-01

    This report describes work conducted by the Oregon Department of Fish and Wildlife (ODFW) and the Washington Department of Fish and Wildlife (WDFW) from 1 October 1999 to 30 September 2000. The work is part of studies to evaluate spawning of fall chinook salmon (Oncorhynchus tshawytscha) and chum salmon (O. keta) below the four lowermost Columbia River dams under the Bonneville Power Administration's Project 99-003. The purpose of this project is twofold: (1) Document the existence of fall chinook and chum populations spawning below Bonneville Dam (river mile (RM) 145), The Dalles Dam (RM 192), John Day Dam (RM 216), and McNary Dam (RM 292) (Figure 1) and estimate the size of these populations; and (2) Profile stocks for important population characteristics; including spawning time, genetic make-up, emergence timing, migration size and timing, and juvenile to adult survival rates.

  8. Evaluation of Fall Chinook and Chum Salmon Spawning below Bonneville Dam; 2003-2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    van der Naald, Wayne; Duff, Cameron; Brooks, Robert (Oregon Department of Fish and Wildlife, Columbia River Section, John Day, OR)

    2005-01-01

    In 2003 a total of 253 adult fall chinook and 113 chum were sampled for biological data in the Ives and Pierce islands area below Bonneville Dam. Vital statistics were developed from 221 fall chinook and 109 chum samples. The peak redd count for fall chinook was 190. The peak redd count for chum was 262. Peak spawning time for fall chinook was set at approximately 24 November. Peak spawning time for chum occurred approximately 24 November. There were estimated to be a total of 1,533 fall chinook spawning below Bonneville Dam in 2003. The study area's 2003 chum population was estimated to be 688 spawning fish. Temperature unit data suggests that below Bonneville Dam 2003 brood bright stock, fall chinook emergence began on January 6, 2004 and ended 28 April 2004, with peak emergence occurring 13 April. 2003 brood juvenile chum emergence below Bonneville Dam began 22 February and continued through 15 April 2004. Peak chum emergence took place 25 March. A total of 25,433 juvenile chinook and 4,864 juvenile chum were sampled between the dates of 20 January and 28 June 2004 below Bonneville Dam. Juvenile chum migrated from the study area in the 40-55 mm fork length range. Migration of chum occurred during the months of March, April and May. Sampling results suggest fall chinook migration from rearing areas took place during the month of June 2004 when juvenile fall chinook were in the 65 to 80 mm fork length size range. Adult and juvenile sampling below Bonneville Dam provided information to assist in determining the stock of fall chinook and chum spawning and rearing below Bonneville Dam. Based on observed spawning times, adult age and sex composition, juvenile emergence timing, juvenile migration timing and juvenile size at the time of migration, it appears that in 2003 all of the fall chinook using the area below Bonneville Dam were of a late-spawning, bright stock. Observed spawning times, adult age and sex composition, GSI and DNA analysis, juvenile emergence

  9. Effects of Hyporheic Exchange Flows on Egg Pocket Water Temperature in Snake River Fall Chinook Salmon Spawning Areas

    Energy Technology Data Exchange (ETDEWEB)

    Hanrahan, Timothy P.; Geist, David R.; Arntzen, Evan V.; Abernethy, Cary S.

    2004-09-24

    The development of the Snake River hydroelectric system has affected fall chinook salmon smolts by shifting their migration timing to a period when downstream reservoir conditions are unfavorable for survival. Subsequent to the Snake River chinook salmon fall-run Evolutionary Significant Unit being listed as Threatened under the Endangered Species Act, recovery planning has included changes in hydrosystem operations to improve water temperature and flow conditions during the juvenile chinook salmon summer migration period. In light of the limited water supplies from the Dworshak reservoir for summer flow augmentation, and the associated uncertainties regarding benefits to migrating fall chinook salmon smolts, additional approaches for improved smolt survival need to be evaluated. This report describes research conducted by PNNL that evaluated relationships among river discharge, hyporheic zone characteristics, and egg pocket water temperature in Snake River fall chinook salmon spawning areas. The potential for improved survival would be gained by increasing the rate at which early life history events proceed (i.e., incubation and emergence), thereby allowing smolts to migrate through downstream reservoirs during early- to mid-summer when river conditions are more favorable for survival. PNNL implemented this research project throughout 160 km of the Hells Canyon Reach (HCR) of the Snake River. The hydrologic regime during the 2002?2003 sampling period exhibited one of the lowest, most stable daily discharge patterns of any of the previous 12 water years. The vertical hydraulic gradients (VHG) between the river and the riverbed suggested the potential for predominantly small magnitude vertical exchange. The VHG also showed little relationship to changes in river discharge at most sites. Despite the relatively small vertical hydraulic gradients at most sites, the results from the numerical modeling of riverbed pore water velocity and hyporheic zone temperatures

  10. Applying a two-dimensional morphodynamic model to assess impacts to Chinook salmon spawning habitat from dam removal

    Science.gov (United States)

    Lee, A. A.; Crosato, A.; Omer, A. Y. A.; Bregoli, F.

    2017-12-01

    The need for accurate and robust predictive methods of assessing fluvial ecosystems is highlighted by the accelerating practice of dam removal. Dam removal can be a restorative measure, but the sudden release of impounded sediment and change in flow regime may negatively impact aquatic biota and their habitat. This study assesses the performance of a quasi-three-dimensional morphodynamic numerical model, coupled with habitat suitability indices, to predict short-term impacts to Chinook salmon (Oncorhynchus tshawytscha) spawning habitat from dam removal. The 2007 removal of Marmot Dam on the Sandy River (Oregon, U.S.A.) is used as a case study. Delft3D-FLOW is employed to simulate changes in river channel topography, sediment composition and hydrodynamic conditions for a 20-kilometer reach of the Sandy River. The transport of non-uniform sediment and three-dimensional flow effects are included in the model. Output parameters such as flow depth, velocity and substrate are processed to evaluate habitat quality in the year following the Marmot Dam removal. Impacts are evaluated across four life-stages of Chinook salmon. As a hindcast analysis, the morphodynamic model sufficiently reproduces the evolution of river morphology at the reach-scale while requiring only a low level of calibration. The model performs well in predicting impacts to fish passage, but carries more uncertainty for developing life stages. By coupling flow-sediment-biota interactions, this method shows strong potential for habitat assessment in unsteady and non-uniform environments. Computation time is a primary constraint, as it limits grid-cell resolution, modelling of suspended sediment and capacity to characterize the sediment grain size distribution. Research on the effects of suspended sediment on habitat quality is ongoing, and further research is recommended for modelling reservoir erosion processes numerically.

  11. Conceptual Spawning Habitat Model to Aid in ESA Recovery Plans for Snake River Fall Chinook Salmon, 2002-2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Geist, David (Pacific Northwest National Laboratory)

    2005-09-01

    The goal of this project is to develop a spawning habitat model that can be used to determine the physical habitat factors that are necessary to define the production potential for fall chinook salmon that spawn in large mainstem rivers like the Columbia River's Hanford Reach and Snake River. This project addresses RPA 155 in the NMFS 2000 Biological Opinion: Action 155: BPA, working with BOR, the Corps, EPA, and USGS, shall develop a program to: (1) Identify mainstem habitat sampling reaches, survey conditions, describe cause-and-effect relationships, and identify research needs; (2) Develop improvement plans for all mainstem reaches; and (3) Initiate improvements in three mainstem reaches. During FY 2003 we continued to collect and analyze information on fall chinook salmon spawning habitat characteristics in the Hanford Reach that will be used to address RPA 155, i.e., items 1-3 above. For example, in FY 2003: (1) We continued to survey spawning habitat in the Hanford Reach and develop a 2-dimensional hydraulic and habitat model that will be capable of predicting suitability of fall chinook salmon habitat in the Hanford Reach; (2) Monitor how hydro operations altered the physical and chemical characteristics of the river and the hyporheic zone within fall chinook salmon spawning areas in the Hanford Reach; (3) Published a paper on the impacts of the Columbia River hydroelectric system on main-stem habitats of fall chinook salmon (Dauble et al. 2003). This paper was made possible with data collected on this project; (4) Continued to analyze data collected in previous years that will ultimately be used to identify cause-and-effect relationships and identify research needs that will assist managers in the improvement of fall chinook habitat quality in main-stem reaches. During FY 2004 we plan to: (1) Complete preliminary reporting and submit papers based on the results of the project through FY 2004. Although we have proposed additional analysis of data be

  12. 1998-1999 evaluation of fall chinook and chum salmon spawning below Bonneville, The Dalles, John Day and McNary dams

    International Nuclear Information System (INIS)

    Naald, W.D. van der

    2001-01-01

    This report describes work conducted by the Oregon Department of Fish and Wildlife (ODFW) and the Washington Department of Fish and Wildlife (WDFW) from 1 October 1998 to 30 September 1999. The work is part of studies to evaluate spawning of fall chinook salmon (Oncorhynchus tshawytscha) and chum salmon (O. keta) below the four lowermost Columbia River dams under the Bonneville Power Administration's Project 99-003. The purpose of this project is twofold: (1) Document the existence of fall chinook and chum populations spawning below Bonneville Dam (river mile (RM) 145), The Dalles Dam (RM 192), John Day Dam (RM 216), and McNary Dam (RM 292) (Figure 1) and estimate the size of these populations; and (2) Profile stocks for important population characteristics; including spawning time, genetic make-up, emergence timing, migration size and timing, and juvenile to adult survival rates. Specific tasks conducted by ODFW and WDFW during this period were: (1) Documentation of fall chinook and chum spawning below Bonneville, The Dalles, John Day and McNary dams using on-water observations; (2) Collection of biological data to profile stocks in areas described in Task 1; (3) Determination of spawning population estimates and age composition, average size at return, and sex ratios in order to profile stocks in areas described in Task 1; (4) Collection of data to determine stock origin of adult salmon found in areas described in Task 1; (5) Determination of possible stock origins of adult salmon found in areas described in Task 1 using tag rates based on coded-wire tag recoveries and genetic baseline analysis; (6) Determination of emergence timing and hatching rate of juvenile fall chinook and chum below Bonneville Dam; (7) Determination of migration time and size for juvenile fall chinook and chum rearing in the area described in Task 6; (8) Investigation of feasibility of determining stock composition of juvenile fall chinook and chum rearing in the area described in Task 6

  13. Evaluation of Fall Chinook and Chum Salmon Spawning below Bonneville, The Dalles, John Day, and McNary Dams; 2000-2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    van der Naald, Wayne; Clark, Roy; Spellman, Bryant (Oregon Department of Fish and Wildlife, Portland, OR)

    2002-09-17

    This report describes work conducted by the Oregon Department of Fish and Wildlife (ODFW) and the Washington Department of Fish and Wildlife (WDFW) from 1 October 2000 to 30 September 2001. The work is part of studies to evaluate spawning of fall chinook salmon (Oncorhynchus tshawytscha) and chum salmon (O. keta) below the four lowermost Columbia River dams under the Bonneville Power Administration's Project 99-003. The purpose of this project is twofold: (1) Document the existence of fall chinook and chum populations spawning below Bonneville Dam (river mile (RM) 145), The Dalles Dam (RM 192), John Day Dam (RM 216), and McNary Dam (RM 292) (Figure 1) and estimate the size of these populations. (2) Profile stocks for important population characteristics; including spawning time, genetic make-up, emergence timing, migration size and timing, and juvenile to adult survival rates. Specific tasks conducted by ODFW and WDFW during this period were: (1) Documentation of fall chinook and chum spawning below Bonneville, The Dalles, John Day and McNary dams using on-water observations; (2) Collection of biological data to profile stocks in areas described in Task 1; (3) Determination of spawning population estimates and age composition, average size at return, and sex ratios in order to profile stocks in areas described in Task 1; (4) Collection of data to determine stock origin of adult salmon found in areas described in Task 1; (5) Determination of possible stock origins of adult salmon found in areas described in Task 1 using tag rates based on coded-wire tag recoveries and genetic baseline analysis; (6) Determination of emergence timing and hatching rate of juvenile fall chinook and chum below Bonneville Dam; (7) Determination of migration time and size for juvenile fall chinook and chum rearing in the area described in Task 6; (8) Investigation of feasibility of determining stock composition of juvenile fall chinook and chum rearing in the area described in Task 6

  14. Impacts of environmental variability and global warming scenario on Pacific bluefin tuna ( Thunnus orientalis) spawning grounds and recruitment habitat

    Science.gov (United States)

    Kimura, Shingo; Kato, Yoshiki; Kitagawa, Takashi; Yamaoka, Naoki

    2010-07-01

    Pacific bluefin tuna ( Thunnus orientalis) have spawning grounds in waters stretching from south of Okinawa to east of Taiwan. This species is typical of fishes that spawn seasonally in small, limited areas. Any marked change in the marine environment of the spawning grounds is likely to have a direct impact on larval survival and growth. We conducted rearing experiments on larvae to investigate these impacts and found that a reduction in temperature resulted in poor growth during the juvenile stage, even if larval survival rates did not change. In the wild, this reduced growth rate is likely to reduce survival rates because smaller juveniles have poorer swimming ability and their ability to avoid predators is also reduced. This is especially important since the Kuroshio current, which connects the spawning grounds to the nursery grounds, transports larvae rapidly because of its faster surface current (the western boundary current), thus larvae arriving too quickly in coastal waters can be exposed to very cold temperatures. An ocean model (MIROC) simulation under a climate warming scenario ( IPCC, 2007) predicted that the temperature in the spawning ground would be 3 °C higher in 2100 than in present time, while the transport to nursery grounds would also be faster. In this case, the combination of several mechanisms would control the recruitment of juvenile bluefin. On the spawning grounds, high temperatures exceeding the optimal range would increase larvae mortality and any surviving larvae would reach the nursery grounds more quickly, but warmer coastal waters would have less negative impact on their growth. We forced a model of larval drift with MIROC output fields to study the complex response of bluefin tuna recruitment. As a result, the predicted survival rates of larvae arriving in Japanese coastal waters in 2100 would decline to 36% of present recruitment levels.

  15. Monitoring the Reproductive Success of Naturally Spawning Hatchery and Natural Spring Chinook Salmon in the Wenatchee River, 2008-2009 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Ford, Michael J.; Williamson, Kevin S. [Northwest Fisheries Science Center

    2009-05-28

    We investigated differences in the statistical power to assign parentage between an artificially propagated and wild salmon population. The propagated fish were derived from the wild population, and are used to supplement its abundance. Levels of genetic variation were similar between the propagated and wild groups at 11 microsatellite loci, and exclusion probabilities were >0.999999 for both groups. The ability to unambiguously identify a pair of parents for each sampled progeny was much lower than expected, however. Simulations demonstrated that the proportion of cases the most likely pair of parents were the true parents was lower for propagated parents than for wild parents. There was a clear relationship between parentage assignment ability and the degree of linkage disequilibrium, the estimated effective number of breeders that produced the parents, and the size of the largest family within the potential parents. If a stringent threshold for parentage assignment was used, estimates of relative fitness were biased downward for the propagated fish. The bias appeared to be largely eliminated by either fractionally assigning progeny among parents in proportion to their likelihood of parentage, or by assigning progeny to the most likely set of parents without using a statistical threshold. We used a DNA-based parentage analysis to measure the relative reproductive success of hatchery- and natural-origin spring Chinook salmon in the natural environment. Both male and female hatchery-origin fish produced far fewer juvenile progeny per parent when spawning naturally than did natural origin fish. Differences in age structure, spawning location, weight and run timing were responsible for some of the difference in fitness. Male size and age had a large influence on fitness, with larger and older males producing more offspring than smaller or younger individuals. Female size had a significant effect on fitness, but the effect was much smaller than the effect of size on

  16. Linking spawning ground extent to environmental factors - patterns and dispersal during the egg phase of four North Sea fishes

    DEFF Research Database (Denmark)

    Höffle, Hannes; van Damme, Cindy J. G.; Fox, Clive J.

    2018-01-01

    , the location of the spawning grounds appeared stable on the broad scale but centres of egg abundance varied between the surveyed years. Potential effects of long-term climate change and anthropogenic short-term disturbances, such as seismic surveys, on fish reproduction are discussed, pointing out the demand...

  17. Effects of Hyporheic Exchange Flows on Egg Pocket Water Temperature in Snake River Fall Chinook Salmon Spawning Areas, 2002-2003 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hanrahan, T.; Geist, D.; Arntzen, C. (Pacific Northwest National Laboratory)

    2004-09-01

    The development of the Snake River hydroelectric system has affected fall Chinook salmon smolts by shifting their migration timing to a period (mid- to late-summer) when downstream reservoir conditions are unfavorable for survival. Subsequent to the Snake River Chinook salmon fall-run Evolutionary Significant Unit being listed as Threatened under the Endangered Species Act, recovery planning has included changes in hydrosystem operations (e.g., summer flow augmentation) to improve water temperature and flow conditions during the juvenile Chinook salmon summer migration period. In light of the limited water supplies from the Dworshak reservoir for summer flow augmentation, and the associated uncertainties regarding benefits to migrating fall Chinook salmon smolts, additional approaches for improved smolt survival need to be evaluated. This report describes research conducted by the Pacific Northwest National Laboratory (PNNL) that evaluated relationships among river discharge, hyporheic zone characteristics, and egg pocket water temperature in Snake River fall Chinook salmon spawning areas. This was a pilot-scale study to evaluate these relationships under existing operations of Hells Canyon Dam (i.e., without any prescribed manipulations of river discharge) during the 2002-2003 water year. The project was initiated in the context of examining the potential for improving juvenile Snake River fall Chinook salmon survival by modifying the discharge operations of Hells Canyon Dam. The potential for improved survival would be gained by increasing the rate at which early life history events proceed (i.e., incubation and emergence), thereby allowing smolts to migrate through downstream reservoirs during early- to mid-summer when river conditions are more favorable for survival. PNNL implemented this research project at index sites throughout 160 km of the Hells Canyon Reach (HCR) of the Snake River. The HCR extends from Hells Canyon Dam (river kilometer [rkm] 399

  18. Differential use of salmon by vertebrate consumers: implications for conservation

    Directory of Open Access Journals (Sweden)

    Taal Levi

    2015-08-01

    Full Text Available Salmon and other anadromous fish are consumed by vertebrates with distinct life history strategies to capitalize on this ephemeral pulse of resource availability. Depending on the timing of salmon arrival, this resource may be in surplus to the needs of vertebrate consumers if, for instance, their populations are limited by food availability during other times of year. However, the life history of some consumers enables more efficient exploitation of these ephemeral resources. Bears can deposit fat and then hibernate to avoid winter food scarcity, and highly mobile consumers such as eagles, gulls, and other birds can migrate to access asynchronous pulses of salmon availability. We used camera traps on pink, chum, and sockeye salmon spawning grounds with various run times and stream morphologies, and on individual salmon carcasses, to discern potentially different use patterns among consumers. Wildlife use of salmon was highly heterogeneous. Ravens were the only avian consumer that fed heavily on pink salmon in small streams. Eagles and gulls did not feed on early pink salmon runs in streams, and only moderately at early sockeye runs, but were the dominant consumers at late chum salmon runs, particularly on expansive river flats. Brown bears used all salmon resources far more than other terrestrial vertebrates. Notably, black bears were not observed on salmon spawning grounds despite being the most frequently observed vertebrate on roads and trails. From a conservation and management perspective, all salmon species and stream morphologies are used extensively by bears, but salmon spawning late in the year are disproportionately important to eagles and other highly mobile species that are seasonally limited by winter food availability.

  19. Two-dimensional hydrodynamic modeling to quantify effects of peak-flow management on channel morphology and salmon-spawning habitat in the Cedar River, Washington

    Science.gov (United States)

    Czuba, Christiana; Czuba, Jonathan A.; Gendaszek, Andrew S.; Magirl, Christopher S.

    2010-01-01

    The Cedar River in Washington State originates on the western slope of the Cascade Range and provides the City of Seattle with most of its drinking water, while also supporting a productive salmon habitat. Water-resource managers require detailed information on how best to manage high-flow releases from Chester Morse Lake, a large reservoir on the Cedar River, during periods of heavy precipitation to minimize flooding, while mitigating negative effects on fish populations. Instream flow-management practices include provisions for adaptive management to promote and maintain healthy aquatic habitat in the river system. The current study is designed to understand the linkages between peak flow characteristics, geomorphic processes, riverine habitat, and biological responses. Specifically, two-dimensional hydrodynamic modeling is used to simulate and quantify the effects of the peak-flow magnitude, duration, and frequency on the channel morphology and salmon-spawning habitat. Two study reaches, representative of the typical geomorphic and ecologic characteristics of the Cedar River, were selected for the modeling. Detailed bathymetric data, collected with a real-time kinematic global positioning system and an acoustic Doppler current profiler, were combined with a LiDAR-derived digital elevation model in the overbank area to develop a computational mesh. The model is used to simulate water velocity, benthic shear stress, flood inundation, and morphologic changes in the gravel-bedded river under the current and alternative flood-release strategies. Simulations of morphologic change and salmon-redd scour by floods of differing magnitude and duration enable water-resource managers to incorporate model simulation results into adaptive management of peak flows in the Cedar River. PDF version of a presentation on hydrodynamic modelling in the Cedar River in Washington state. Presented at the American Geophysical Union Fall Meeting 2010.

  20. Characteristics of genetic factors that influence gender in Atlantic salmon

    OpenAIRE

    Cheung, Cliff

    2011-01-01

    Very little is currently known about how gender is established in Atlantic salmon, and environmental and commercial matters have increased interest in the life history strategies of this ancient fish. It is necessary to assess the sex ratios in populations of Atlantic salmon both before they head out to oceanic feeding grounds and when they return to spawn, before we can begin to understand the mechanisms that govern gender in this species. Much of the challenge faced by those studying gender...

  1. Traveling around Cape Horn: Otolith chemistry reveals a mixed stock of Patagonian hoki with separate Atlantic and Pacific spawning grounds

    Science.gov (United States)

    Schuchert, P.C.; Arkhipkin, A.I.; Koenig, A.E.

    2010-01-01

    Trace element fingerprints of edge and core regions in otoliths from 260 specimens of Patagonian hoki, Macruronus magellanicus L??nnberg, 1907, were analyzed by LA-ICPMS to reveal whether this species forms one or more population units (stocks) in the Southern Oceans. Fish were caught on their spawning grounds in Chile and feeding grounds in Chile and the Falkland Islands. Univariate and multivariate analyses of trace element concentrations in the otolith edges, which relate to the adult life of fish, could not distinguish between Atlantic (Falkland) and Pacific (Chile) hoki. Cluster analyses of element concentrations in the otolith edges produced three different clusters in all sample areas indicating high mixture of the stocks. Cluster analysis of trace element concentrations in the otolith cores, relating to juvenile and larval life stages, produced two separate clusters mainly distinguished by 137Ba concentrations. The results suggest that Patagonian hoki is a highly mixed fish stock with at least two spawning grounds around South America. ?? 2009 Elsevier B.V.

  2. Impact of naturally spawning captive-bred Atlantic salmon on wild populations: depressed recruitment and increased risk of climate-mediated extinction.

    Science.gov (United States)

    McGinnity, Philip; Jennings, Eleanor; DeEyto, Elvira; Allott, Norman; Samuelsson, Patrick; Rogan, Gerard; Whelan, Ken; Cross, Tom

    2009-10-22

    The assessment report of the 4th International Panel on Climate Change confirms that global warming is strongly affecting biological systems and that 20-30% of species risk extinction from projected future increases in temperature. It is essential that any measures taken to conserve individual species and their constituent populations against climate-mediated declines are appropriate. The release of captive bred animals to augment wild populations is a widespread management strategy for many species but has proven controversial. Using a regression model based on a 37-year study of wild and sea ranched Atlantic salmon (Salmo salar) spawning together in the wild, we show that the escape of captive bred animals into the wild can substantially depress recruitment and more specifically disrupt the capacity of natural populations to adapt to higher winter water temperatures associated with climate variability. We speculate the mechanisms underlying this seasonal response and suggest that an explanation based on bio-energetic processes with physiological responses synchronized by photoperiod is plausible. Furthermore, we predict, by running the model forward using projected future climate scenarios, that these cultured fish substantially increase the risk of extinction for the studied population within 20 generations. In contrast, we show that positive outcomes to climate change are possible if captive bred animals are prevented from breeding in the wild. Rather than imposing an additional genetic load on wild populations by releasing maladapted captive bred animals, we propose that conservation efforts should focus on optimizing conditions for adaptation to occur by reducing exploitation and protecting critical habitats. Our findings are likely to hold true for most poikilothermic species where captive breeding programmes are used in population management.

  3. Escapement monitoring of adult chinook salmon in the Secesh River and Lake Creek, Idaho, 1999; ANNUAL

    International Nuclear Information System (INIS)

    Faurot, Dave; Kucera, Paul A.

    2001-01-01

    differences between the two methodologies. The fish counting stations did not impede salmon movements, nor was spawning displaced downstream. Fish moved freely upstream and downstream through the fish counting structures. Fish movement was greatest between the period of 10:00 p. m. and 4:00 a. m. There appeared to be a segment of ''nomadic'' males that moved into and out of the spawning area, apparently seeking other mates to spawn with. This methodology has the potential to provide more consistent and accurate salmon spawner abundance information than single-pass and multiple-pass spawning ground surveys. Accurate adult escapement information would allow managers to determine if recovery actions benefited listed chinook salmon in tributary streams

  4. Journey of the Oncorhynchus: A Story of the Pacific Northwest Salmon.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1994-06-01

    This report tells the story of the Pacific Northwest salmon in words that children can understand. The life cycle of chinook salmon is depicted through pictures and elementary language from the egg to juvenile fish in fresh water, to maturing fish in the ocean, and the adults migrating back up to spawning grounds in the Columbia River. This can be very useful in the education of children.

  5. Atlantic bluefin tuna Thunnus thynnus feeding ecology in the northern Gulf of Mexico: a preliminary description of diet from the western Atlantic spawning grounds.

    Science.gov (United States)

    Butler, C M; Logan, J M; Provaznik, J M; Hoffmayer, E R; Staudinger, M D; Quattro, J M; Roberts, M A; Ingram, G W; Pollack, A G; Lutcavage, M E

    2015-01-01

    A combination of stomach contents, nitrogen stable-isotope and tissue C:N values are presented to demonstrate feeding activity of Atlantic bluefin tuna Thunnus thynnus on the Gulf of Mexico (GOMEX) spawning grounds. Diets include teleosts, cephalopods, crustaceans and a pelagic tunicate (Pyrosoma atlanticum). Results reveal the need to classify the GOMEX as a T. thynnus feeding ground. © 2014 The Fisheries Society of the British Isles.

  6. Juvenile Pacific Salmon in Puget Sound

    National Research Council Canada - National Science Library

    Fresh, Kurt L

    2006-01-01

    Puget sound salmon (genus Oncorhynchus) spawn in freshwater and feed, grow and mature in marine waters, During their transition from freshwater to saltwater, juvenile salmon occupy nearshore ecosystems in Puget Sound...

  7. Escapement Monitoring of Adult Chinook Salmon in the Secesh River and Lake Creek, Idaho, 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Faurot, Dave; Kucera, Paul A. (Nez Perce Tribe, Lapwai, ID)

    2001-04-01

    differences between the two methodologies. The fish counting stations did not impede salmon movements, nor was spawning displaced downstream. Fish moved freely upstream and downstream through the fish counting structures. Fish movement was greatest between the period of 10:00 p. m. and 4:00 a. m. There appeared to be a segment of ''nomadic'' males that moved into and out of the spawning area, apparently seeking other mates to spawn with. This methodology has the potential to provide more consistent and accurate salmon spawner abundance information than single-pass and multiple-pass spawning ground surveys. Accurate adult escapement information would allow managers to determine if recovery actions benefited listed chinook salmon in tributary streams.

  8. Evaluation of Fall Chinook and Chum Salmon Spawning below Bonneville, The Dalles, John Day, and McNary Dams; 2001-2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    van der Naald, Wayne; Clark, Roy; Spellman, Bryant (Oregon Department of Fish and Wildlife, Portland, OR)

    2003-04-01

    In 2001 a total of 309 adult fall chinook and 264 chum were sampled in the Ives and Pierce islands area below Bonneville Dam. The peak redd count for fall chinook was 48. The peak redd count for chum was 181. Peak spawning time for fall chinook was set at approximately 16 November. Peak spawning time for chum occurred approximately 26 November. There were estimated to be a total of 721 fall chinook spawning below Bonneville Dam in 2001. The 2001 chum population below Bonneville Dam was estimated to be 532 spawning fish. Temperature unit data suggests that below Bonneville Dam 2001 brood chinook emergence began on 11 March 2002 and ended 18 May 2002, with peak emergence occurring 26 April. 2001 brood juvenile chum emergence below Bonneville Dam began 29 January and continued through 31 March 2002. Peak chum emergence took place 25 February. A total of 5,487 juvenile chinook and 678 juvenile chum were sampled between the dates of 22 January and 30 July 2002 below Bonneville Dam. Juvenile chum migrated from the study area in the 40-55 mm fork length range. Migration of chum occurred during the months of March, April and May. Sampling results suggest fall chinook migration from rearing areas took place from mid June through early July 2002 when juvenile fall chinook were in the 65 to 80 mm fork length size range. Adult and juvenile sampling below Bonneville Dam provided information to assist in determining the stock of fall chinook and chum spawning and rearing below Bonneville Dam. Based on observed spawning times, adult age and sex composition, GSI analysis, juvenile emergence timing, juvenile migration timing and juvenile size at the time of migration, it appears that in 2001 and 2002 the majority of fall chinook using the area below Bonneville Dam were of a late-spawning bright stock of fall chinook. Observed spawning times, adult age and sex composition, GSI analysis, juvenile emergence timing, juvenile migration timing and juvenile size at the time of migration

  9. Overlap between Atlantic bluefin tuna spawning grounds and observed Deepwater Horizon surface oil in the northern Gulf of Mexico.

    Science.gov (United States)

    Muhling, B A; Roffer, M A; Lamkin, J T; Ingram, G W; Upton, M A; Gawlikowski, G; Muller-Karger, F; Habtes, S; Richards, W J

    2012-04-01

    The 2010 Deepwater Horizon oil spill impacted the northern Gulf of Mexico (GOM) during the spring spawning season of Atlantic bluefin tuna (BFT). Overlap between BFT spawning habitat and surface oil in the northern GOM was examined using satellite-derived estimates of oil coverage, and spawning habitat models. Results suggested that although eggs and larvae were likely impacted by oil-contaminated waters in the eastern GOM, high abundances of larvae were located elsewhere, especially in the western GOM. Overall, less than 10% of BFT spawning habitat was predicted to have been covered by surface oil, and less than 12% of larval BFT were predicted to have been located within contaminated waters in the northern GOM, on a weekly basis. Our results provide preliminary but important initial estimates of the effects of the spill on larval BFT mortality, as concern continues over the appropriate management responses to impacts of the spill. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. Adult Chinook Salmon Abundance Monitoring in the Secesh River and Lake Creek, Idaho, 2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Faurot, Dave; Kucera, Paul A.

    2001-05-01

    respectively. Peak net upstream adult movement at the Secesh River site occurred June 28 and at the Lake Creek site on June 27. Peak of total movement was August 16 at Secesh River and August 7 at Lake Creek. The last fish passed through the Lake Creek fish counting station on August 31 and on September 8 at the Secesh River site. Migrating salmon in the Secesh River and Lake Creek exhibited two behaviorally distinct segments of fish movement. The first segment of movement was characterized, mainly, by upstream movement only. The second segment consisted of upstream and downstream movement with very little net upstream movement. The fish counting stations did not impede salmon movements, nor was spawning displaced downstream. Fish moved freely upstream and downstream through the fish counting structures. Fish movement was greatest between the period of 5:00 p.m. and 4:00 a.m. There appeared to be a segment of ''nomadic'' males that moved into and out of the spawning area, apparently seeking other mates to spawn with. The downstream movement of salmon allowed by this fish counting station design may be an important factor affecting reproductive success as male salmon seek other females to spawn with. Traditional weirs operated for broodstock collection do not allow for downstream movement of adults. This methodology has the potential to provide more consistent and accurate salmon spawner abundance information than single-pass and multiple-pass spawning ground surveys. Accurate adult abundance would allow managers to determine if recovery actions were benefiting these salmon spawning aggregates and if recovery goals were being met.

  11. Bio-physical model provides insight into dispersal of plaice (Pleuronectes platessa L.) from putative spawning grounds to nursery areas on the west coast of Ireland

    Science.gov (United States)

    Zölck, Melanie; Brophy, Deirdre; Mohn, Christian; Minto, Cóilín; McGrath, David

    2015-05-01

    In this study we use an individual-based coupled physical biological model (ICPBM) to reconstruct the dispersal pathways of 0-group juveniles (young of the year) collected from nursery grounds in Galway Bay and to identify probable spawning ground locations for plaice on the west coast of Ireland. The relative importance of passive transport, behaviour and individual growth rates on successful larval delivery, from three putative spawning grounds to suitable nursery areas, was also investigated. Using a hydrodynamic Regional Ocean Modelling System (ROMS), combined with a particle tracking model, three model scenarios were tested: a passive tracer scenario (PTS), a linear growth scenario (LGS) and a temperature-dependent growth scenario (TDS). Hydrodynamic conditions were modelled and biological information (pelagic larval durations and size at settlement) incorporated. The LGS and TDS included vertical migration and tidally synchronised behaviour. Generalized Linear Model (GLM) comparisons showed that incorporation of behaviour and temperature-dependent growth, resulted in approximately two to three times more particles being delivered to sites of suitable depth for settlement (≤ 10 m), compared to passive transport alone (p histories between particles that were delivered to shallow inshore areas and those that failed to reach depths suitable for settlement indicated that dispersal to coastal nursery areas is facilitated by entrainment into a cool coastal current system. This study identifies a probable plaice spawning area in western Ireland and reconfirms the importance of including behaviour and growth in dispersal simulations. The model results suggest that differences in growth can influence larval delivery to potentially suitable nursery areas.

  12. The final spawning ground of Tachypleus gigas (Müller, 1785 on the east Peninsular Malaysia is at risk: a call for action

    Directory of Open Access Journals (Sweden)

    Bryan Raveen Nelson

    2016-07-01

    oxygen (5.5–8.0 mg l−1 and moisture depth (6.2–10.2 cm. In view of the sustained anthropogenic pressure on the coastal habitats on one hand and decreasing horseshoe crabs population on the other, it is crucial to implement both conservation and management measures for T. gigas at Pantai Balok. Failing that may lead to the loss of this final spawning ground on the east coast of P. Malaysia.

  13. The final spawning ground of Tachypleus gigas (Müller, 1785) on the east Peninsular Malaysia is at risk: a call for action.

    Science.gov (United States)

    Nelson, Bryan Raveen; Satyanarayana, Behara; Moh, Julia Hwei Zhong; Ikhwanuddin, Mhd; Chatterji, Anil; Shaharom, Faizah

    2016-01-01

    (-1)) and moisture depth (6.2-10.2 cm). In view of the sustained anthropogenic pressure on the coastal habitats on one hand and decreasing horseshoe crabs population on the other, it is crucial to implement both conservation and management measures for T. gigas at Pantai Balok. Failing that may lead to the loss of this final spawning ground on the east coast of P. Malaysia.

  14. Influences of sex and activity level on physiological changes in individual adult sockeye salmon during rapid senescence.

    Science.gov (United States)

    Hruska, Kimberly A; Hinch, Scott G; Healey, Michael C; Patterson, David A; Larsson, Stefan; Farrell, Anthony P

    2010-01-01

    A noninvasive biopsy protocol was used to sample plasma and gill tissue in individual sockeye salmon (Oncorhynchus nerka) during the critical life stage associated with spawning-arrival at a spawning channel through senescence to death several days later. Our main objective was to characterize the physiological changes associated with rapid senescence in terms of the physiological stress/cortisol hypersecretion model and the energy exhaustion model. Salmon lived an average of 5 d in the spawning channel, during which time there were three major physiological trends that were independent of sexual status: a large increase in plasma indicators of stress and exercise (i.e., lactate and cortisol), a decrease in the major plasma ions (i.e., Cl(-) and Na(+)) and osmolality, and a decrease in gross somatic energy reserves. Contrary to a generalized stress response, plasma glucose decreased in approximately 2/3 of the fish after arrival, as opposed to increasing. Furthermore, plasma cortisol levels at spawning-ground arrival were not correlated with the degree of ionoregulatory changes during rapid senescence. One mechanism of mortality in some fish may involve the exhaustion of energy reserves, resulting in the inability to mobilize plasma glucose. Sex had a significant modulating effect on the degree of physiological change. Females exhibited a greater magnitude of change for gross somatic energy, osmolality, and plasma concentrations of Cl(-), Na(+), cortisol, testosterone, 11-ketotestosterone, 17,20beta-progesterone, and estradiol. The activity level of an individual on the spawning grounds appeared to influence the degree of some physiological changes during senescence. For example, males that received a greater frequency of attacks exhibited larger net decreases in plasma 11-ketotestosterone while on the spawning grounds. These results suggest that rapid senescence on spawning grounds is influenced by multiple physiological processes and perhaps behavior. This study

  15. Trophic Ecology of Atlantic Bluefin Tuna (Thunnusthynnus) Larvae from the Gulf of Mexico and NW Mediterranean Spawning Grounds: A Comparative Stable Isotope Study

    Science.gov (United States)

    Malca, Estrella; Quintanilla, José María; Muhling, Barbara A.; Alemany, Francisco; Privoznik, Sarah L.; Shiroza, Akihiro; Lamkin, John T.; García, Alberto

    2015-01-01

    The present study uses stable isotopes of nitrogen and carbon (δ15Nandδ13C) as trophic indicators for Atlantic bluefin tuna larvae (BFT) (6–10 mm standard length) in the highly contrasting environmental conditions of the Gulf of Mexico (GOM) and the Balearic Sea (MED). These regions are differentiated by their temperature regime and relative productivity, with the GOM being significantly warmer and more productive. MED BFT larvae showed the highest δ15N signatures, implying an elevated trophic position above the underlying microzooplankton baseline. Ontogenetic dietary shifts were observed in the BFT larvae from the GOM and MED which indicates early life trophodynamics differences between these spawning habitats. Significant trophic differences between the GOM and MED larvae were observed in relation to δ15N signatures in favour of the MED larvae, which may have important implications in their growth during their early life stages.These low δ15N levels in the zooplankton from the GOM may be an indication of a shifting isotopic baseline in pelagic food webs due to diatrophic inputs by cyanobacteria. Lack of enrichment for δ15N in BFT larvae compared to zooplankton implies an alternative grazing pathway from the traditional food chain of phytoplankton—zooplankton—larval fish. Results provide insight for a comparative characterization of the trophic pathways variability of the two main spawning grounds for BFT larvae. PMID:26225849

  16. Trophic ecology of Atlantic Bluefin Tuna (Thunnus thynnus) [corrected] larvae from the Gulf of Mexico and NW Mediterranean spawning grounds: A Comparative Stable Isotope Study.

    Science.gov (United States)

    Laiz-Carrión, Raúl; Gerard, Trika; Uriarte, Amaya; Malca, Estrella; Quintanilla, José María; Muhling, Barbara A; Alemany, Francisco; Privoznik, Sarah L; Shiroza, Akihiro; Lamkin, John T; García, Alberto

    2015-01-01

    The present study uses stable isotopes of nitrogen and carbon (δ15Nandδ13C) as trophic indicators for Atlantic bluefin tuna larvae (BFT) (6-10 mm standard length) in the highly contrasting environmental conditions of the Gulf of Mexico (GOM) and the Balearic Sea (MED). These regions are differentiated by their temperature regime and relative productivity, with the GOM being significantly warmer and more productive. MED BFT larvae showed the highest δ15N signatures, implying an elevated trophic position above the underlying microzooplankton baseline. Ontogenetic dietary shifts were observed in the BFT larvae from the GOM and MED which indicates early life trophodynamics differences between these spawning habitats. Significant trophic differences between the GOM and MED larvae were observed in relation to δ15N signatures in favour of the MED larvae, which may have important implications in their growth during their early life stages.These low δ15N levels in the zooplankton from the GOM may be an indication of a shifting isotopic baseline in pelagic food webs due to diatrophic inputs by cyanobacteria. Lack of enrichment for δ15N in BFT larvae compared to zooplankton implies an alternative grazing pathway from the traditional food chain of phytoplankton-zooplankton-larval fish. Results provide insight for a comparative characterization of the trophic pathways variability of the two main spawning grounds for BFT larvae.

  17. Trophic ecology of Atlantic Bluefin Tuna (Thunnus thynnus [corrected] larvae from the Gulf of Mexico and NW Mediterranean spawning grounds: A Comparative Stable Isotope Study.

    Directory of Open Access Journals (Sweden)

    Raúl Laiz-Carrión

    Full Text Available The present study uses stable isotopes of nitrogen and carbon (δ15Nandδ13C as trophic indicators for Atlantic bluefin tuna larvae (BFT (6-10 mm standard length in the highly contrasting environmental conditions of the Gulf of Mexico (GOM and the Balearic Sea (MED. These regions are differentiated by their temperature regime and relative productivity, with the GOM being significantly warmer and more productive. MED BFT larvae showed the highest δ15N signatures, implying an elevated trophic position above the underlying microzooplankton baseline. Ontogenetic dietary shifts were observed in the BFT larvae from the GOM and MED which indicates early life trophodynamics differences between these spawning habitats. Significant trophic differences between the GOM and MED larvae were observed in relation to δ15N signatures in favour of the MED larvae, which may have important implications in their growth during their early life stages.These low δ15N levels in the zooplankton from the GOM may be an indication of a shifting isotopic baseline in pelagic food webs due to diatrophic inputs by cyanobacteria. Lack of enrichment for δ15N in BFT larvae compared to zooplankton implies an alternative grazing pathway from the traditional food chain of phytoplankton-zooplankton-larval fish. Results provide insight for a comparative characterization of the trophic pathways variability of the two main spawning grounds for BFT larvae.

  18. Rainbow trout movement behavior and habitat occupancy are influenced by sex and Pacific salmon presence in an Alaska river system

    Science.gov (United States)

    Fraley, Kevin M.; Falke, Jeffrey A.; McPhee, Megan V.; Prakash, Anupma

    2017-01-01

    We used spatially continuous field-measured and remotely-sensed aquatic habitat characteristics paired with weekly ground-based telemetry tracking and snorkel surveys to describe movements and habitat occupancy of adult rainbow trout (N = 82) in a runoff-fed, salmon-influenced southcentral Alaska river system. We found that during the ice-free feeding season (June through September) rainbow trout occurrence was associated more with fine-scale (channel unit) characteristics relative to coarse-scale (stream reach) variables. The presence of Pacific salmon (which provide an important seasonal food subsidy), and habitat size were particularly useful predictors. Weekly movement distance differed between pre- and post- spawning salmon arrival, but did not vary by sex. Habitat quality, season, and the arrival of spawning salmon influenced the likelihood of rainbow trout movement, and fish moved farther to seek out higher quality habitats. Because rainbow trout respond to habitat factors at multiple scales and seek out salmon-derived subsidies, it will be important to take a multiscale approach in protecting trout and salmon populations and managing the associated fisheries.

  19. Rainbow trout movement behavior and habitat occupancy are influenced by sex and Pacific salmon presence in an Alaska river system

    Science.gov (United States)

    Fraley, Kevin M.; Falke, Jeffrey A.; McPhee, Megan V.; Prakash, Anupma

    2018-01-01

    We used spatially continuous field-measured and remotely-sensed aquatic habitat characteristics paired with weekly ground-based telemetry tracking and snorkel surveys to describe movements and habitat occupancy of adult rainbow trout (N = 82) in a runoff-fed, salmon-influenced southcentral Alaska river system. We found that during the ice-free feeding season (June through September) rainbow trout occurrence was associated more with fine-scale (channel unit) characteristics relative to coarse-scale (stream reach) variables. The presence of Pacific salmon (which provide an important seasonal food subsidy), and habitat size were particularly useful predictors. Weekly movement distance differed between pre- and post- spawning salmon arrival, but did not vary by sex. Habitat quality, season, and the arrival of spawning salmon influenced the likelihood of rainbow trout movement, and fish moved farther to seek out higher quality habitats. Because rainbow trout respond to habitat factors at multiple scales and seek out salmon-derived subsidies, it will be important to take a multiscale approach in protecting trout and salmon populations and managing the associated fisheries.

  20. Grande Ronde Basin endemic spring chinook salmon supplementation program

    International Nuclear Information System (INIS)

    1998-02-01

    As part of its responsibilities under the Northwest Power Act (Pacific Northwest Electric Power Planning and Conservation Act of 1980), Bonneville Power Administration (BPA) must mitigate the loss of fish, wildlife, and related spawning grounds and habitat attributable to power production at federal hydroelectric dams on the Columbia River and its tributaries. The federal dams have been identified as a major source of mortality for the listed Snake River salmon stocks. BPA also has responsibilities under the Endangered Species Act (ESA) of 1973 to operate in a way that does not jeopardize the continued existence of listed species and to use its agency resources to conserve listed species

  1. Time-delayed subsidies: interspecies population effects in salmon.

    Directory of Open Access Journals (Sweden)

    Michelle C Nelson

    Full Text Available Cross-boundary nutrient inputs can enhance and sustain populations of organisms in nutrient-poor recipient ecosystems. For example, Pacific salmon (Oncorhynchus spp. can deliver large amounts of marine-derived nutrients to freshwater ecosystems through their eggs, excretion, or carcasses. This has led to the question of whether nutrients from one generation of salmon can benefit juvenile salmon from subsequent generations. In a study of 12 streams on the central coast of British Columbia, we found that the abundance of juvenile coho salmon was most closely correlated with the abundance of adult pink salmon from previous years. There was a secondary role for adult chum salmon and watershed size, followed by other physical characteristics of streams. Most of the coho sampled emerged in the spring, and had little to no direct contact with spawning salmon nutrients at the time of sampling in the summer and fall. A combination of techniques suggest that subsidies from spawning salmon can have a strong, positive, time-delayed influence on the productivity of salmon-bearing streams through indirect effects from previous spawning events. This is the first study on the impacts of nutrients from naturally-occurring spawning salmon on juvenile population abundance of other salmon species.

  2. Consumption choice by bears feeding on salmon.

    Science.gov (United States)

    Gende, S M; Quinn, T P; Willson, M F

    2001-05-01

    Consumption choice by brown (Ursus arctos) and black bears (U. americanus) feeding on salmon was recorded for over 20,000 bear-killed fish from 1994 to 1999 in Bristol Bay (sockeye salmon, Oncorhynchus nerka) and southeastern Alaska (pink, O. gorbuscha and chum salmon O. keta). These data revealed striking patterns of partial and selective consumption that varied with relative availability and attributes of the fish. As the availability of salmon decreased, bears consumed a larger proportion of each fish among both years and habitats. When availability was high (absolute number and density of salmon), bears consumed less biomass per captured fish, targeting energy-rich fish (those that had not spawned) or energy-rich body parts (eggs in females; brain in males). In contrast, individual fish were consumed to a much greater extent, regardless of sex or spawning status, in habitats or years of low salmon availability. The proportion of biomass consumed per fish was similar for males and females, when spawning status was statistically controlled, but bears targeted different body parts: the body flesh, brain and dorsal hump in males and the roe in females. Bears thus appeared to maximize energy intake by modifying the amount and body parts consumed, based on availability and attributes of spawning salmon.

  3. Spawning characteristics of Clupea pallasii in the coastal waters off Gyeongnam, Korea, during spawning season

    Science.gov (United States)

    Lee, Yong-Deuk; Choi, Jung Hwa; Moon, Seong Yong; Lee, Sun Kil; Gwak, Woo-Seok

    2017-12-01

    The purpose of this study is to research the characteristics of spawning grounds of Clupea pallasii found at 1 spawning ground located in the coast of Yeongun-ri, Tongyeong, Gyeongnam, and 3 stations in Jinhae Bay. Diving observation was performed from January to June, 2014 at the coast of Yeongun-ri, and from February to June, 2016 at Jinhae Bay after total 4 stations (A: Gusan-myeon, B: Haengamdong, C: Hacheong-myeon, D: Jam-do) were constituted. During observation period, 1 spawning ground was found in Tongyeong area in January. In Jinhae Bay spawning grounds were found at 3 stations (A, B, D) out of 4 stations in February. Regarding the surrounding environment of spawning ground found at Yeongunri, Tongyeong, various kinds of seaweeds were distributed up to 1-5 m depth, and many branch type red algae were distributed. In case of Jinhae Bay, seaweeds were widely distributed from shallow water to 5 m depth. In addition, the scope that eggs were attached was considerably wide compared to Tongyeong area, and they were found at all the 3 spots, so C. pallasii is thought to use Jinhae Bay for its spawning ground widely. Eggs were attached from the surface to 3-4 m, and like Tongyeong area, eggs were attached to mostly branch type of red algae. The results of this study suggest that the spawning season of the C. pallasii in coast waters off Gyeongnam is until mid-February.

  4. Upstream passage, spawning, and stock identification of fall chinook in the Snake River, 1992 and 1993. Final report

    International Nuclear Information System (INIS)

    Blankenship, H.L.; Mendel, G.W.

    1997-05-01

    This final report of the 3-year study summarizes activities and results for 1993. Study objectives were to: (1) determine the source of losses (or accounting errors) for adult chinook salmon between Ice Harbor Dam (IHR) and Lower Granite Dam (LGR), and upstream of LGR in the Snake River; (2) identify spawning locations upstream of LGR for calibration of aerial redd surveys, redd habitat mapping, carcass recovery for genetic stock profile analysis, and correction of estimated adult/redd ratios; and (3) estimate passage and migration times at Snake River. 200 fall chinook salmon were radio tagged and tracked with aerial, fixed-site, and ground mobile tracking. Fish were released upstream of IHR at Charbonneau Park (CHAR). 190 of the fish were tracked or relocated away from CHAR. 59 fish descended to below IHR without crossing Lower Monumental Dam (LMO). Another 128 salmon passed upstream of LMO without falling back at IHR. Only 80 salmon passed Little Goose Dam (LGO) without falling back at a downstream dam; 66 of these fish passed LGR. Many fish that fell back reascended the dams. A total of 72 salmon released at CHAR passed upstream of LGR, including fish that had fallen back and reascended a dam. Over 80 percent of the salmon that entered Lyons Ferry Hatchery each year had reached LGO before descending to the hatchery. Extensive wandering was documented between LMO and upstream of LGR before salmon entered Lyons Ferry Hatchery or the Tucannon River. In 1993, 41 salmon were found to be of hatchery origin when recovered. These fish entered Lyons Ferry Hatchery with similar movements to unmarked salmon. Each year a few salmon have remained near the hatchery without entering, which suggests the hatchery may have inadequate attraction flows. Fall chinook passed lower Snake River dams in 2-5 days each on average. Median travel times through LMO and LGO were 1.0-1.3 days each, which was slower than for spring chinook or steelhead in 1993. 5 refs., 21 figs., 20 tabs

  5. Status and restoration of salmon (Salmo salar L. stocks in the Nemunas River Basin, Lithuania

    Directory of Open Access Journals (Sweden)

    Vytautas Kesminas

    2015-12-01

    Full Text Available Dynamics of salmon resources is of a great importance to most countries in the Baltic Sea region, including Lithuania. Currently, human activity is the main cause of negative impact on salmon stocks status mainly through habitat loss. Salmon restocking program started in 1998 with the aim to recover stocks in the Nemunas River basin. The program involved artificial rearing, construction of fish ladders, protection of spawning grounds, stock monitoring, fishery regulation in the sea and rivers. Our study presents data on salmon stocks status and productivity in Lithuania, including abundance of fry and smolts, age composition and genetic structure of the populations. In total, 12 rivers in Lithuania have salmon populations, but the status of the populations varies. Despite the many measures taken, smolt production in Nemunas basin is increasing slowly. Notable increase in production was observed only in recent years. Production increased substantially during 2007- 2010 period, from 13 thousand individuals to over 47 thousand. Salmon parr density in studied rivers varied from 0.3 – 33.7 per 100 m² (mean value 9.8 individuals per 100 m². Mitochondrial, microsatellite and SNP DNA markers were used to investigate genetic structure of salmon populations. MtDNA was subjected to RFLP analysis, 17 microsatellite loci were used as markers, also samples genotyped with 5568 SNPs. Salmon population from the Nemunas basin was fixed at one haplotype for mtDNA and fell into the same group as the populations from Latvia, Estonia, Russia and Southern Sweden. Microsatellite DNA and SNPs demonstrated distinctiveness from other neighboring populations, however it also indicated lower genetic variability, which could be caused by bottleneck event.

  6. The effect of exposure to farmed salmon on piscine orthoreovirus infection and fitness in wild Pacific salmon in British Columbia, Canada.

    Directory of Open Access Journals (Sweden)

    Alexandra Morton

    Full Text Available The disease Heart and Skeletal Muscle Inflammation (HSMI is causing substantial economic losses to the Norwegian salmon farming industry where the causative agent, piscine orthoreovirus (PRV, is reportedly spreading from farmed to wild Atlantic salmon (Salmo salar with as yet undetermined impacts. To assess if PRV infection is epidemiologically linked between wild and farmed salmon in the eastern Pacific, wild Pacific salmon (Oncorhynchus sp. from regions designated as high or low exposure to salmon farms and farmed Atlantic salmon reared in British Columbia (BC were tested for PRV. The proportion of PRV infection in wild fish was related to exposure to salmon farms (p = 0.0097. PRV was detected in: 95% of farmed Atlantic salmon, 37-45% of wild salmon from regions highly exposed to salmon farms and 5% of wild salmon from the regions furthest from salmon farms. The proportion of PRV infection was also significantly lower (p = 0.0008 where wild salmon had been challenged by an arduous return migration into high-elevation spawning habitat. Inter-annual PRV infection declined in both wild and farmed salmon from 2012-2013 (p ≤ 0.002. These results suggest that PRV transfer is occurring from farmed Atlantic salmon to wild Pacific salmon, that infection in farmed salmon may be influencing infection rates in wild salmon, and that this may pose a risk of reduced fitness in wild salmon impacting their survival and reproduction.

  7. Deschutes River Spawning Gravel Study, Volume I, Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Huntington, Charles W.

    1985-09-01

    Spawning habitat in the Deschutes River was inventoried, gravel permeability and composition were sampled at selected gravel bars, historical flow records for the Deschutes were analyzed, salmon and trout utilization of spawning habitat was examined, and potential methods of enhancing spawning habitat in the river were explored. Some changes in river conditions since the mid-1960's were identified, including a reduction in spawning habitat immediately downstream from the hydroelectric complex. The 1964 flood was identified as a factor which profoundly affected spawning habitat in the river, and which greatly complicated efforts to identify recent changes which could be attributed to the hydrocomplex. A baseline on present gravel quality at both chinook and steelhead spawning areas in the river was established using a freeze-core methodology. Recommendations are made for enhancing spawning habitat in the Deschutes River, if it is independently determined that spawning habitat is presently limiting populations of summer steelhead or fall chinook in the river. 53 refs., 40 figs., 21 tabs.

  8. Captive Rearing Initiative for Salmon River Chinook Salmon, 1998-1999 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hassemer, Peter F.

    2001-04-01

    During 1999, the Idaho Department of Fish and Game (IDFG) continued developing techniques for the captive rearing of chinook salmon Oncorhynchus tshawytscha. Techniques under development included protocols for rearing juveniles in freshwater and saltwater hatchery environments, and fieldwork to collect brood year 1998 and 1999 juveniles and eggs and to investigate the ability of these fish to spawn naturally. Fish collected as juveniles were held for a short time at the Sawtooth Fish Hatchery and later transferred to the Eagle Fish Hatchery for rearing. Eyed-eggs were transferred immediately to the Eagle Fish Hatchery where they were disinfected and reared by family groups. When fish from either collection method reached approximately 60 mm, they were PIT tagged and reared separately by brood year and source stream. Sixteen different groups were in culture at IDFG facilities in 1999. Hatchery spawning activities of captive-reared chinook salmon produced eyed-eggs for outplanting in streamside incubation chambers in the West Fork Yankee Fork Salmon River (N=2,297) and the East Fork Salmon River (N=1,038). Additionally, a number of these eggs were maintained at the Eagle Fish Hatchery to ensure adequate brood year 1999 representation from these systems, and produced 279 and 87 juveniles from the West Fork Yankee Fork and East Fork Salmon River, respectively. Eyed-eggs were not collected from the West Fork Yankee Fork due to low adult escapement. Brood year 1998 juveniles were collected from the Lemhi River (N=191), West Fork Yankee Fork Salmon River (N=229), and East Fork Salmon River (N=185). Additionally, brood year 1999 eyed-eggs were collected from the Lemhi River (N=264) and East Fork Salmon River (N=143). Sixty-two and seven maturing adults were released into Bear Valley Creek (Lemhi River system) and the East Fork Salmon River, respectively, for spawning evaluation in 1999. Nine female carcasses from Bear Valley Creek were examined for egg retention, and of

  9. Captive Rearing Initiative for Salmon River Chinook Salmon, 1999 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hassemer, Peter F.

    2001-04-01

    During 1999, the Idaho Department of Fish and Game (IDFG) continued developing techniques for the captive rearing of chinook salmon Oncorhynchus tshawytscha. Techniques under development included protocols for rearing juveniles in freshwater and saltwater hatchery environments, and fieldwork to collect brood year 1998 and 1999 juveniles and eggs and to investigate the ability of these fish to spawn naturally. Fish collected as juveniles were held for a short time at the Sawtooth Fish Hatchery and later transferred to the Eagle Fish Hatchery for rearing. Eyed-eggs were transferred immediately to the Eagle Fish Hatchery where they were disinfected and reared by family groups. When fish from either collection method reached approximately 60 mm, they were PIT tagged and reared separately by brood year and source stream. Sixteen different groups were in culture at IDFG facilities in 1999. Hatchery spawning activities of captive-reared chinook salmon produced eyed-eggs for outplanting in streamside incubation chambers in the West Fork Yankee Fork Salmon River (N=2,297) and the East Fork Salmon River (N=1,038). Additionally, a number of these eggs were maintained at the Eagle Fish Hatchery to ensure adequate brood year 1999 representation from these systems, and produced 279 and 87 juveniles from the West Fork Yankee Fork and East Fork Salmon River, respectively. Eyed-eggs were not collected from the West Fork Yankee Fork due to low adult escapement. Brood year 1998 juveniles were collected from the Lemhi River (N=191), West Fork Yankee Fork Salmon River (N=229), and East Fork Salmon River (N=185). Additionally, brood year 1999 eyed-eggs were collected from the Lemhi River (N=264) and East Fork Salmon River (N=143). Sixty-two and seven maturing adults were released into Bear Valley Creek (Lemhi River system) and the East Fork Salmon River, respectively, for spawning evaluation in 1999. Nine female carcasses from Bear Valley Creek were examined for egg retention, and of

  10. Predation on Chinook Salmon parr by hatchery salmonids and Fallfish in the Salmon River, New York

    Science.gov (United States)

    Johnson, James H.; Nack, Christopher C.; Chalupnicki, Marc; Abbett, Ross; McKenna, James E.

    2016-01-01

    Naturally reproduced Chinook Salmon Oncorhynchus tshawytscha contribute substantially to the fishery in Lake Ontario. The Salmon River, a Lake Ontario tributary in New York, produces the largest numbers of naturally spawned Chinook Salmon, with parr abundance in the river often exceeding 10 million. In the spring of each year, large numbers of hatchery salmonid yearlings—potential predators of Chinook Salmon parr—are released into the Salmon River by the New York State Department of Environmental Conservation. We sought to examine predation on Chinook Salmon parr in the Salmon River during May and June prior to out-migration. Over the 4 years examined (2009–2012), annual consumption of Chinook Salmon parr by hatchery-released yearling steelhead O. mykiss and Coho Salmon O. kisutch ranged from 1.5 to 3.3 million and from 0.4 to 2.1 million, respectively. In 2009, Fallfish Semotilus corporalis were estimated to consume 2.9 million Chinook Salmon parr. Predation was higher in May, when the average TL of Chinook Salmon parr was 44.5 mm, than in June. Fallfish were also important predators of naturally reproduced steelhead subyearlings, consuming an estimated 800,000 steelhead in 2009. Hatchery-released yearling salmonids consumed 13.8–15.3% of the Chinook Salmon parr that were estimated to be present in the Salmon River during 2010–2012. Earlier releases of hatchery salmonid yearlings could reduce the riverine consumption of Chinook Salmon parr by facilitating the out-migration of yearlings prior to Chinook Salmon emergence.

  11. Effects of salmon-derived nutrients and habitat characteristics on population densities of stream-resident sculpins.

    Directory of Open Access Journals (Sweden)

    Noel R Swain

    Full Text Available Movement of nutrients across ecosystem boundaries can have important effects on food webs and population dynamics. An example from the North Pacific Rim is the connection between productive marine ecosystems and freshwaters driven by annual spawning migrations of Pacific salmon (Oncorhynchus spp. While a growing body of research has highlighted the importance of both pulsed nutrient subsidies and disturbance by spawning salmon, their effects on population densities of vertebrate consumers have rarely been tested, especially across streams spanning a wide range of natural variation in salmon densities and habitat characteristics. We studied resident freshwater prickly (Cottus asper, and coastrange sculpins (C. aleuticus in coastal salmon spawning streams to test whether their population densities are affected by spawning densities of pink and chum salmon (O. gorbuscha and O. keta, as well as habitat characteristics. Coastrange sculpins occurred in the highest densities in streams with high densities of spawning pink and chum salmon. They also were more dense in streams with high pH, large watersheds, less area covered by pools, and lower gradients. In contrast, prickly sculpin densities were higher in streams with more large wood and pools, and less canopy cover, but their densities were not correlated with salmon. These results for coastrange sculpins provide evidence of a numerical population response by freshwater fish to increased availability of salmon subsidies in streams. These results demonstrate complex and context-dependent relationships between spawning Pacific salmon and coastal ecosystems and can inform an ecosystem-based approach to their management and conservation.

  12. Coho salmon dependence on intermittent streams.

    Science.gov (United States)

    P.J. Wigington; J.L. Ebersole; M.E. Colvin; S.G. Leibowitz; B. Miller; B. Hansen; H. Lavigne; D. White; J.P. Baker; M.R. Church; J.R. Brooks; M.A. Cairns; J.E. Compton

    2006-01-01

    In this paper, we quantify the contributions of intermittent streams to coho salmon production in an Oregon coastal watershed. We provide estimates of (1) proportion of spawning that occurred in intermittent streams, (2) movement of juveniles into intermittent streams, (3) juvenile survival in intermittent and perennial streams during winter, and (4) relative size of...

  13. Pacific salmon (Oncorhynchus spp.) runs and consumer fitness: growth and energy storage in stream-dwelling salmonids increase with salmon spawner density

    Science.gov (United States)

    Rinella, Daniel J.; Wipfli, Mark S.; Stricker, Craig A.; Heintz, Ron A.; Rinella, Matthew J.

    2012-01-01

    We examined how marine-derived nutrients (MDN), in the form of spawning Pacific salmon, influenced the nutritional status and δ15N of stream-dwelling fishes. We sampled juvenile coho salmon (Oncorhynchus kisutch) and Dolly Varden (Salvelinus malma) during spring and fall from 11 south-central Alaskan streams that ranged widely in spawning salmon biomass (0.1–4.7 kg·m–2). Growth rate (as indexed by RNA–DNA ratios), energy density, and δ15N enrichment in spring-sampled fishes increased with spawner biomass, indicating the persistence of spawner effects more than 6 months after salmon spawning. Point estimates suggest that spawner effects on nutrition were substantially greater for coho salmon than Dolly Varden (268% and 175% greater for growth and energy, respectively), indicating that both species benefitted physiologically, but that juvenile coho salmon accrued more benefits than Dolly Varden. Although the data were less conclusive for fall- than spring-sampled fish, they do suggest spawner effects were also generally positive during fall, soon after salmon spawned. In a follow-up analysis where growth rate and energy density were modeled as a function of δ15N enrichment, results suggested that both increased with MDN assimilation, especially in juvenile coho salmon. Our results support the importance of salmon runs to the nutritional ecology of stream-dwelling fishes.

  14. Fate of chlorinated fatty acids in migrating sockeye salmon and their transfer to arctic grayling

    DEFF Research Database (Denmark)

    Mu, Huiling; Ewald, G.; Nilsson, E.

    2004-01-01

    To investigate whether biotransport constitutes an entry route into pristine ecosystems for nonpersistent, nonvolatile xenobiotic compounds, extractable organically bound halogen in sockeye salmon (Oncorhynchus nerka) from Alaska was determined before and after spawning migration. The major organ...... originating from the salmon, demonstrating a long-range transport route for this type of pollutants to pristine areas....... to that of the unchlorinated fatty acids. Lipids of the Arctic grayling (Thymallus arcticus), a fish resident to the spawning lake of the salmon, contained higher concentrations of chlorinated fatty acids than grayling in a lake without migratory salmon. This may reflect a food-chain transfer of the chlorinated fatty acids...

  15. Genomic organization and evolution of the trace amine-associated receptor (TAAR) repertoire in Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Tessarolo, Jordan A; Tabesh, Mohammad J; Nesbitt, Michael; Davidson, William S

    2014-04-22

    There is strong evidence that olfaction plays a key role in the homing of salmonids to their natal spawning grounds, particularly in the freshwater phase. However, the physiological and genetic mechanisms behind this biological phenomenon are largely unknown. It has been shown that Pacific salmon respond to dissolved free amino acids from their natal streams. This indicates that amino acids comprise part of the olfcatory cues for imprinting and homing in salmonids. As trace amine-associated receptors (TAARs), a class of olfactory receptors that are close relatives of the G protein-coupled aminergic neurotransmitter receptors, recognize amino acid metabolites, we hypothesize that TAARs play an important role in salmon homing by recognizing olfactory cues. Therefore, to better understand homing in Atlantic salmon, we set out to characterize the TAAR genes in this species. We searched the first assembly of the Atlantic salmon genome for sequences resembling TAARs previously characterized in other teleosts. We identified 27 putatively functional TAAR genes and 25 putative TAAR pseudogenes, which cluster primarily on chromosome 21 (Ssa21). Phylogenetic analysis of TAAR amino acid sequences from 15 vertebrate species revealed the TAAR gene family arose after the divergence of jawed and jawless vertebrates. The TAARs group into three classes with salmon possessing class I and class III TAARs. Within each class, evolution is characterized by species-specific gene expansions, which is in contrast to what is observed in other olfactory receptor families (e.g., OlfCs and oras). Copyright © 2014 Tessarolo et al.

  16. American dippers indicate contaminant biotransport by Pacific salmon.

    Science.gov (United States)

    Morrissey, Christy A; Pollet, Ingrid L; Ormerod, Steve J; Elliott, John E

    2012-01-17

    Migrating salmon can increase productivity in Pacific Northwestern streams and lakes through the deposition of nutrients from their decomposing carcasses after spawning. Several studies also report simultaneous biotransport of persistent organic pollutants that have contaminated lake food webs, although no similar effect has been shown conclusively in rivers. We tested the prediction that salmon enhance contaminants in river food webs using the American dipper (Cinclus mexicanus), an aquatic songbird and a recognized indicator of stream quality. Over 3 years, we analyzed 29 dipper eggs and aquatic invertebrate samples from 14 different rivers in 10 catchments in southern British Columbia, Canada to assess whether variations in autumn spawning density of Pacific salmon were reflected in dipper egg contamination or stable carbon and nitrogen isotopes. δ(13)C isotope signatures, but not δ(15)N, in aquatic invertebrates and dipper eggs increased among catchments in proportion to the average density of spawning salmon. Concentrations of brominated flame retardants (PBDEs), dichlorodiphenyltrichloroethane metabolites (DDTs), and chlordane compounds were related in part to the δ(13)C measure of salmon density, but mercury, chlorobenzenes, and polychlorinated biphenyls (PCBs) were explained better by dipper trophic level. We conclude that spawning Pacific salmon result in the increased availability of salmon fry as dipper prey and salmon are a significant source of PBDEs, DDTs, and chlordanes to river ecosystems. However, contrary to lake studies, postspawn concentrations of legacy PCBs in river birds, even in salmon-rich rivers, were not significantly higher than would be expected from atmospheric deposition alone. We recommend using δ(13)C isotopes to trace salmon-derived lipids which may persist over winter particularly in rivers, and are potentially a better reflection of lipophilic contaminant transfer.

  17. Climatic and anthropogenic factors changing spawning pattern and production zone of Hilsa fishery in the Bay of Bengal

    Directory of Open Access Journals (Sweden)

    M. Shohidullah Miah

    2015-03-01

    Full Text Available Hilsa (Tenualosa ilisha Hamilton as a single species accounts 12% for more than half of the total marine catches. About 2% of the entire population of the country is directly or indirectly engaged with Hilsa fishing. Hilsa has a wide geographical distribution in Asia from the Persian Gulf to the South China Sea. Particularly large stocks are found in Upper Bay of Bengal (BoB region sustained by the large river systems. The global Hilsa catch is reported 75% from Bangladesh water, 15% from Myanmar, 5% from India and 5% from other countries such as Thailand and Iran. Hilsa is a highly migratory and anadromous fish with the same migratory and same breeding behavior as that of Atlantic Salmon fish (Salmo sp.. Due to various anthropogenic activities, climate change effect, increased siltation and rising of the river basins, the migratory routes as well as spawning grounds of Hilsa are disturbed, displaced or even destroyed. During last two decades hilsa production from inland water declined about 20%, whereas marine water yield increased about 3 times. Major Hilsa to catch has been gradually shifted from inland to marine water. Hilsa fish ascend for spawning migration from sea into estuaries. It has been found that the major spawning areas have been shifted to the lower estuarine regions of Hatia, Sandwip and Bhola. At the spawning ground of Hilsa, the fishing level F=1.36 yr−1, where in the river Meghna the Fmsy=0.6 yr−1 and exploitation rate E=0.70 is (Emsy>0.5. Oceanographic changes viz. high turbidity increased flooding, more tidal action and changes of salinity etc. have accelerated the change of migration patterns of spawning, growth and its production. Hilsa fecundity ranges from 1.5 to 2.0 million eggs for fish ranging in length from 35 to 50 cm. Hilsa fecundity is declining in different areas due to climate change and the declining fecundity impacting greatly on Hilsa production. Due to shifting of the spawning ground at the lower

  18. Organic salmon

    DEFF Research Database (Denmark)

    Ankamah Yeboah, Isaac; Nielsen, Max; Nielsen, Rasmus

    . This study identifies the price premium on organic salmon in the Danish retail sale sector using consumer panel scanner data for households by applying the hedonic price model while permitting unobserved heterogeneity between households. A premium of 20% for organic salmon is found. Since this premium...... is closer to organic labeled agriculture products than to ecolabelled capture fisheries products, it indicates that consumers value organic salmon as an agriculture product more than fisheries product....

  19. Physicochemical characteristics of the hyporheic zone affect redd site selection of chum and fall chinook salmon, Columbia River, 2001

    International Nuclear Information System (INIS)

    Geist, David R.

    2001-01-01

    Chum salmon (Oncorhynchus keta) may historically have been the most abundant species of Columbia River salmon, contributing as much as 50% of the total biomass of all salmon in the Pacific Ocean prior to the 1940's (Neave 1961). By the 1950's, however, run sizes to the Columbia River dropped dramatically and in 1999 the National Marine Fisheries Service (NMFS) listed Columbia River chum salmon as threatened under the Endangered Species Act (ESA; NMFS 1999). Habitat degradation, water diversions, harvest, and artificial propagation are the major human-induced factors that have contributed to the species decline (NMFS 1998). Columbia River chum salmon spawn exclusively in the lower river below Bonneville Dam, including an area near Ives Island. The Ives Island chum salmon are part of the Columbia River evolutionary significant unit (ESU) for this species, and are included in the ESA listing. In addition to chum salmon, fall chinook salmon (O. tshawytscha) also spawn at Ives Island. Spawning surveys conducted at Ives Island over the last several years show that chum and fall chinook salmon spawned in clusters in different locations (US Fish and Wildlife Service and Washington Department of Fish and Wildlife, unpublished data). The presence of redd clusters suggested that fish were selecting specific habitat features within the study area (Geist and Dauble 1998). Understanding the specific features of these spawning areas is needed to quantify the amount of habitat available to each species so that minimum flows can be set to protect fish and maintain high quality habitat

  20. Migratory salmonid redd habitat characteristics in the Salmon River, New York

    Science.gov (United States)

    Johnson, James H.; Nack, Christopher C.; McKenna, James E.

    2010-01-01

    Non-native migratory salmonids ascend tributaries to spawn in all the Great Lakes. In Lake Ontario, these species include Chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), steelhead (O. mykiss), and brown trout (Salmo trutta). Although successful natural reproduction has been documented for many of these species, little research has been conducted on their spawning habitat. We examined the spawning habitat of these four species in the Salmon River, New York. Differences in fish size among the species were significantly correlated with spawning site selection. In the Salmon River, the larger species spawned in deeper areas with larger size substrate and made the largest redds. Discriminant function analysis correctly classified redds by species 64–100% of the time. The size of substrate materials below Lighthouse Hill Dam is within the preferred ranges for spawning for these four species indicating that river armoring has not negatively impacted salmonid production. Intra-specific and inter-specific competition for spawning sites may influence redd site selection for smaller salmonids and could be an impediment for Atlantic salmon (S. salar) restoration.

  1. Interactions between brown bears and chum salmon at McNeil River, Alaska

    Science.gov (United States)

    Peirce, Joshua M.; Otis, Edward O.; Wipfli, Mark S.; Follmann, Erich H.

    2013-01-01

    Predation on returning runs of adult salmon (Oncorhynchus spp.) can have a large influence on their spawning success. At McNeil River State Game Sanctuary (MRSGS), Alaska, brown bears (Ursus arctos) congregate in high numbers annually along the lower McNeil River to prey upon returning adult chum salmon (O. keta). Low chum salmon escapements into McNeil River since the late 1990s have been proposed as a potential factor contributing to concurrent declines in bear numbers. The objective of this study was to determine the extent of bear predation on chum salmon in McNeil River, especially on pre-spawning fish, and use those data to adjust the escapement goal for the river. In 2005 and 2006, 105 chum salmon were radiotagged at the river mouth and tracked to determine cause and location of death. Below the falls, predators consumed 99% of tagged fish, killing 59% of them before they spawned. Subsequently, the escapement goal was nearly doubled to account for this pre-spawning mortality and to ensure enough salmon to sustain both predators and prey. This approach to integrated fish and wildlife management at MRSGS can serve as a model for other systems where current salmon escapement goals may not account for pre-spawning mortality.

  2. Poached Salmon

    Science.gov (United States)

    ... 4 salmon steaks, 5 oz each 3 cups water 4 black peppercorns 1 lemon, thickly sliced 3 parsley sprigs 1 small onion, ... pan large enough to hold salmon steaks, bring water to a boil and add peppercorns, lemon slices, parsley, onion, and bay leaves. Lower heat ...

  3. Measurements of key life history metrics of Coho salmon in Pudding Creek, California

    Science.gov (United States)

    David W. Wright; Sean P. Gallagher; Christopher J. Hannon

    2012-01-01

    Since 2005, a life cycle monitoring project in Pudding Creek, California, has utilized a variety of methodologies including an adult trap, spawning surveys, PIT tags, electro-fishing, and a smolt trap to estimate coho salmon adult escapement, juvenile abundance, juvenile growth, winter survival, and marine survival. Adult coho salmon escapement and smolt abundance are...

  4. Spawning Dynamics and Size Related Trends in Reproductive Parameters of Southern Bluefin Tuna, Thunnus maccoyii.

    Directory of Open Access Journals (Sweden)

    Jessica H Farley

    Full Text Available Knowledge of spawning behaviour and fecundity of fish is important for estimating the reproductive potential of a stock and for constructing appropriate statistical models for assessing sustainable catch levels. Estimates of length-based reproductive parameters are particularly important for determining potential annual fecundity as a function of fish size, but they are often difficult to estimate reliably. Here we provide new information on the reproductive dynamics of southern bluefin tuna (SBT Thunnus maccoyii through the analysis of fish size and ovary histology collected on the spawning ground in 1993-1995 and 1999-2002. These are used to refine previous parameter estimates of spawning dynamics and investigate size related trends in these parameters. Our results suggest that the small SBT tend to arrive on the spawning ground slightly later and depart earlier in the spawning season relative to large fish. All females were mature and the majority were classed as spawning capable (actively spawning or non-spawning with a very small proportion classed as regressing. The fraction of females spawning per day decreased with fish size, but once females start a spawning episode, they spawned daily irrespective of size. Mean batch fecundity was estimated directly at 6.5 million oocytes. Analysis of ovary histology and ovary weight data indicated that relative batch fecundity, and the duration of spawning and non-spawning episodes, increased with fish size. These reproductive parameter estimates could be used with estimates of residency time on the spawning ground as a function of fish size (if known and demographic data for the spawning population to provide a time series of relative annual fecundity for SBT.

  5. Acoustic tracking of migrating salmon.

    Science.gov (United States)

    Kupilik, Matthew J; Petersen, Todd

    2014-10-01

    Annual salmon migrations vary significantly in annual return numbers from year to year. In order to determine when a species' sustainable return size has been met, a method for counting and sizing the spawning animals is required. This project implements a probability hypothesis density tracker on data from a dual frequency identification sonar to automate the process of counting and sizing the fish crossing an insonified area. Data processing on the sonar data creates intensity images from which possible fish locations can be extracted using image processing. These locations become the input to the tracker. The probability hypothesis density tracker then solves the multiple target tracking problem and creates fish tracks from which length information is calculated using image segmentation. The algorithm is tested on data from the 2010 salmon run on the Kenai river in Alaska and compares favorably with statistical models from sub-sampling and manual measurements.

  6. Migration and spawning of female surubim (Pseudoplatystoma corruscans, Pimelodidae) in the São Francisco river, Brazil

    Science.gov (United States)

    Godinho, Alexandre L.; Kynard, Boyd; Godinho, Hugo P.

    2007-01-01

    Surubim, Pseudoplatystoma corruscans, is the most valuable commercial and recreational fish in the São Francisco River, but little is known about adult migration and spawning. Movements of 24 females (9.5–29.0 kg), which were radio-tagged just downstream of Três Marias Dam (TMD) at river kilometer 2,109 and at Pirapora Rapids (PR) 129 km downstream of TMD, suggest the following conceptual model of adult female migration and spawning. The tagged surubims used only 274 km of the main stem downstream of TMD and two tributaries, the Velhas and Abaeté rivers. Migration style was dualistic with non-migratory (resident) and migratory fish. Pre-spawning females swam at ground speeds of up to 31 km day-1 in late September–December to pre-spawning staging sites located 0–11 km from the spawning ground. In the spawning season (November–March), pre-spawning females migrated back and forth from nearby pre-spawning staging sites to PR for short visits to spawn, mostly during floods. Multiple visits to the spawning site suggest surubim is a multiple spawner. Most post-spawning surubims left the spawning ground to forage elsewhere, but some stayed at the spawning site until the next spawning season. Post-spawning migrants swam up or downstream at ground speeds up to 29 km day-1 during January–March. Construction of proposed dams in the main stem and tributaries downstream of TMD will greatly reduce surubim abundance by blocking migrations and changing the river into reservoirs that eliminate riverine spawning and non-spawning habitats, and possibly, cause extirpation of populations.

  7. Cedar River Chinook genotypes - Estimate relative reproductive success of hatchery and wild fall Chinook salmon in the Cedar River

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We are using genetic pedigree information to estimate the reproductive success of hatchery and wild fall-run Chinook salmon spawning in the Cedar River, Washington....

  8. Wenatchee Chinook Parentage - Evaluate the reproductive success of hatchery and wild Chinook salmon in the Wenatchee River

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — We are using genetic parentage analysis to measure the relative fitness of hatchery and wild spring run Chinook salmon that spawn in the Wenatchee River. In addition...

  9. Status and Monitoring of Natural and Supplemented Chinook Salmon in Johnson Creek, Idaho, 2006-2007 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Rabe, Craig D.; Nelson, Douglas D. [Nez Perce Tribe

    2008-11-17

    The Nez Perce Tribe Johnson Creek Artificial Propagation Enhancement Project (JCAPE) has conducted juvenile and adult monitoring and evaluation studies for its 10th consecutive year. Completion of adult and juvenile Chinook salmon studies were conducted for the purpose of evaluating a small-scale production initiative designed to increase the survival of a weak but recoverable spawning aggregate of summer Chinook salmon Oncorhynchus tshawytscha. The JCAPE program evaluates the life cycle of natural origin (NOR) and hatchery origin (HOR) supplementation fish to quantify the key performance measures: abundance, survival-productivity, distribution, genetics, life history, habitat, and in-hatchery metrics. Operation of a picket style weir and intensive multiple spawning ground surveys were completed to monitor adult Chinook salmon and a rotary screw trap was used to monitor migrating juvenile Chinook salmon in Johnson Creek. In 2007, spawning ground surveys were conducted on all available spawning habitat in Johnson Creek and one of its tributaries. A total of 63 redds were observed in the index reach and 11 redds for all other reaches for a combined count of 74 redds. Utilization of carcass recovery surveys and adult captures at an adult picket weir yielded a total estimated adult escapement to Johnson Creek of 438 Chinook salmon. Upon deducting fish removed for broodstock (n=52), weir mortality/ known strays (n=12), and prespawning mortality (n=15), an estimated 359 summer Chinook salmon were available to spawn. Estimated total migration of brood year 2005 NOR juvenile Chinook salmon at the rotary screw trap was calculated for three seasons (summer, fall, and spring). The total estimated migration was 34,194 fish; 26,671 of the NOR migrants left in the summer (July 1 to August 31, 2005) as fry/parr, 5,852 left in the fall (September 1 to November 21, 2005) as presmolt, and only 1,671 NOR fish left in the spring (March 1 to June 30, 2006) as smolt. In addition, there

  10. Involvement of 11-ketotestosterone in hooknose formation in male pink salmon (Oncorhynchus gorbuscha) jaws.

    Science.gov (United States)

    Kudo, Hideaki; Kimura, Tomoaki; Hasegawa, Yuya; Abe, Takashi; Ichimura, Masaki; Ijiri, Shigeho

    2018-05-01

    Mature male Pacific salmon (Oncorhynchus spp.) develop a hooknose, as a secondary male sexual characteristic, during the spawning period. It is likely that androgens regulate hooknose formation. However, endocrinological and histochemical details about the relationship between androgens and hooknose formation are poorly understood. In this study, we performed assays of serum androgens, detection of androgen receptor (AR) in hooknose tissues, external morphological measurement of hooknose-related lengths, and microscopic observation of hooknose tissues of pink salmon (O. gorbuscha) at different stages of sexual maturation. Expression of the arβ gene was detected in hooknose tissues of males but not females. The elongation of these tissues was mediated directly via androgens. Serum 11-ketotestosterone (11-KT) concentrations indicated a significant positive correlation with both jaw lengths during sexual maturation of males. In the upper jaw, cartilage tissue developed during hooknose formation, and AR-immunoreactive chondrocytes were located in the rostal-vetral regions of hooknose cartilage in maturing male. The chondrocytes in maturing males before entering into rivers exhibited rich-cytoplasm with high cell activity than at other sexual development stages. On the other hand, in the lower jaw, the development of the spongiosa-like bone meshworks. AR-immunoreactivity was detected in a proportion of the osteocytes and osteoblast-like cells in the spongiosa-like bone meshworks. These results indicate that hooknose formation in pink salmon, which is associated with the buildup of a structure with sufficient strength that it can be used to attack other males on the spawning ground, is regulated by 11-KT. Copyright © 2018 Elsevier Inc. All rights reserved.

  11. Re-Introduction of Lower Columbia River Chum Salmon into Duncan Creek, 2002-2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hillson, Todd D. (Washington Department of Fish and Wildlife, Olympia, WA)

    2003-10-15

    silt and provide shade; (4) annual sampling of gravel in the spawning channels to detect changes in gravel composition and sedimentation levels. Tasks associated with the second goal of the recovery strategy for Lower Columbia River chum are detailed in The Monitoring and Evaluation Plan for the Duncan Creek Chum Salmon Reintroduction Program. Four main questions are used to evaluate the success of this program: (1) what egg-to-fry survival rates are being achieved in the renovated channels, (2) what is the survival of the eggs and fry used in the artificial rearing program in Duncan Creek, (3) what is the survival and spawning ground distribution of adult chum salmon produced from the spawning channels and the artificial rearing program, and (4) what is the straying rate of non-program chum salmon into Duncan Creek. The monitoring portion of the Duncan M&E includes documenting and monitoring the physical attributes of the channels.

  12. Salmon River Habitat Enhancement, 1989 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Mike

    1989-04-01

    This project was funded by the Bonneville Power Administration (BPA). The annual report contains three individual subproject papers detailing tribal fisheries work completed during the summer and fall of 1989. Subproject 1 contains summaries of evaluation/monitoring efforts associated with the Bear Valley Creek, Idaho enhancement project. Subproject 2 contains an evaluation of the Yankee Fork of the Salmon River habitat enhancement project. This report has been sub-divided into two parts: Part 1; stream evaluation and Part 2; pond series evaluation. Subproject 3 concerns the East Fork of the Salmon River, Idaho. This report summarizes the evaluation of the project to date including the 1989 pre-construction evaluation conducted within the East Fork drainage. Dredge mining has degraded spawning and rearing habitat for chinook salmon and steelhead trout in the Yankee Fork drainage of the Salmon River and in Bear Valley Creek. Mining, agricultural, and grazing practices degraded habitat in the East Fork of the Salmon River. Biological monitoring of the success of habitat enhancement for Bear Valley Creek and Yankee Fork are presented in this report. Physical and biological inventories prior to habitat enhancement in East Fork were also conducted. Four series of off-channel ponds of the Yankee Fork are shown to provide effective rearing habitat for chinook salmon. 45 refs., 49 figs., 24 tabs.

  13. Fate of chlorinated fatty acids in migrating sockeye salmon and their transfer to arctic grayling

    DEFF Research Database (Denmark)

    Mu, Huiling; Ewald, G.; Nilsson, E.

    2004-01-01

    organohalogen compounds in the salmon were halogenated fatty acids, predominantly chlorinated species that accounted for up to 35% of the extractable, organically bound chlorine (EOCl) in the fish tissues. The amount of chlorinated fatty acids in the salmon muscle decreased as a result of spawning migration...... to that of the unchlorinated fatty acids. Lipids of the Arctic grayling (Thymallus arcticus), a fish resident to the spawning lake of the salmon, contained higher concentrations of chlorinated fatty acids than grayling in a lake without migratory salmon. This may reflect a food-chain transfer of the chlorinated fatty acids...... originating from the salmon, demonstrating a long-range transport route for this type of pollutants to pristine areas....

  14. Comparing life history characteristics of Lake Michigan’s naturalized and stocked Chinook Salmon

    Science.gov (United States)

    Kerns, Janice A; Rogers, Mark W.; Bunnell, David B.; Claramunt, Randall M.; Collingsworth, Paris D.

    2016-01-01

    Lake Michigan supports popular fisheries for Chinook Salmon Oncorhynchus tshawytscha that have been sustained by stocking since the late 1960s. Natural recruitment of Chinook Salmon in Lake Michigan has increased in the past few decades and currently contributes more than 50% of Chinook Salmon recruits. We hypothesized that selective forces differ for naturalized populations born in the wild and hatchery populations, resulting in divergent life history characteristics with implications for Chinook Salmon population production and the Lake Michigan fishery. First, we conducted a historical analysis to determine if life history characteristics changed through time as the Chinook Salmon population became increasingly naturalized. Next, we conducted a 2-year field study of naturalized and hatchery stocked Chinook Salmon spawning populations to quantify differences in fecundity, egg size, timing of spawning, and size at maturity. In general, our results did not indicate significant life history divergence between naturalized and hatchery-stocked Chinook Salmon populations in Lake Michigan. Although historical changes in adult sex ratio were correlated with the proportion of naturalized individuals, changes in weight at maturity were better explained by density-dependent factors. The field study revealed no divergence in fecundity, timing of spawning, or size at maturity, and only small differences in egg size (hatchery > naturalized). For the near future, our results suggest that the limited life history differences observed between Chinook Salmon of naturalized and hatchery origin will not lead to large differences in characteristics important to the dynamics of the population or fishery.

  15. Secondary sexual characters and sperm traits in coho salmon Oncorhynchus kisutch.

    Science.gov (United States)

    Pitcher, T E; Doucet, S M; Beausoleil, J-M J; Hanley, D

    2009-05-01

    A study was undertaken to examine secondary sexual characters (spawning colouration and overall body size) in relation to sperm metrics in one alternative reproductive tactic of coho salmon Oncorhynchus kisutch: large hooknose males that spawn in dominance-based hierarchies. Males with less intense red spawning colouration had higher sperm velocities than males with darker red spawning colouration. There was no relationship between male body size and sperm metrics. These results suggest that within an alternative reproductive tactic, variation in sperm competition intensity may select for a trade-off between investment in sexual colouration and sperm quality.

  16. Organic salmon

    DEFF Research Database (Denmark)

    Ankamah Yeboah, Isaac; Nielsen, Max; Nielsen, Rasmus

    The year 2016 is groundbreaking for organic aquaculture producers in EU, as it represents the deadline for implementing a full organic life cycle in the aquaculture production. Such a shift induces production costs for farmers and if it should be profitable, they must receive higher prices....... This study identifies the price premium on organic salmon in the Danish retail sale sector using consumer panel scanner data for households by applying the hedonic price model while permitting unobserved heterogeneity between households. A premium of 20% for organic salmon is found. Since this premium...

  17. Hindrances to upstream migration of atlantic salmon (Salmo salar) in a northern Swedish river caused by a hydroelectric power-station

    International Nuclear Information System (INIS)

    Rivinoja, P.; Lundqvist, H.

    2001-01-01

    Many Baltic salmon rivers have lost their natural juvenile production due to human activities blocking or reducing access to their spawning grounds, e.g. damming, power generation, partial hinders, etc.. One such hindrance is a hydroelectric complex located in the lower reaches of River Umeaelven in northern Sweden. Water from the forbay created by the dam Norrfors is directed to the Stornorrfors power-station. At times, 100 per cent of the river is directed to the power-station. Water from the power-station then flows via a tunnel and outlet channel to the river. From the point of the tunnel's discharge into the river, the old river bed acts as a bypass channel directing migrating adult fish to a fish ladder located at the base of the dam. In this study, the effect that an additional turbine, that was installed at the power-station in 1986, had on fish passage run-time was examined. Changes in run-time were compared for two periods 1974-1985 and 1986-1995. In 1997, 55 wild and 25 hatchery salmon were captured in the Umeaelven estuary, radio tagged with uniquely coded tags, and tracked upstream. Both manual and automatic loggers were used to locate fish daily. The main findings show that only 26 per cent of the wild salmon and none of the hatchery salmon found the fish ladder. It is suggested that the salmon followed the main water discharge from the power-station outlet and are thus directed away from the entrance to the bypass channel leading to the fish ladder. Salmon respond by moving upstream or downstream depending on the current flow regimes. The bypass channel consists of partial hinders that may explain why it takes on average 52 days for the salmon to migrate 32 km from the estuary to the fish ladder. Adding a fourth turbine at the power-station did not appear to have changed the timing of the migration or the seasonal distribution of the migrating wild salmon through the fish ladder. There was no significant effect of the fourth turbine on the duration

  18. Innate and adaptive immune responses in migrating spring-run adult chinook salmon, Oncorhynchus tshawytscha

    Science.gov (United States)

    Dolan, Brian P.; Fisher, Kathleen M.; Colvin, Michael E.; Benda, Susan E.; Peterson, James T.; Kent, Michael L.; Schreck, Carl B.

    2016-01-01

    Adult Chinook salmon (Oncorhynchus tshawytscha) migrate from salt water to freshwater streams to spawn. Immune responses in migrating adult salmon are thought to diminish in the run up to spawning, though the exact mechanisms for diminished immune responses remain unknown. Here we examine both adaptive and innate immune responses as well as pathogen burdens in migrating adult Chinook salmon in the Upper Willamette River basin. Messenger RNA transcripts encoding antibody heavy chain molecules slightly diminish as a function of time, but are still present even after fish have successfully spawned. In contrast, the innate anti-bacterial effector proteins present in fish plasma rapidly decrease as spawning approaches. Fish also were examined for the presence and severity of eight different pathogens in different organs. While pathogen burden tended to increase during the migration, no specific pathogen signature was associated with diminished immune responses. Transcript levels of the immunosuppressive cytokines IL-10 and TGF beta were measured and did not change during the migration. These results suggest that loss of immune functions in adult migrating salmon are not due to pathogen infection or cytokine-mediated immune suppression, but is rather part of the life history of Chinook salmon likely induced by diminished energy reserves or hormonal changes which accompany spawning.

  19. Spawning behaviour and post-spawning migration patterns of atlantic bluefin tuna (Thunnus thynnus ascertained from satellite archival tags.

    Directory of Open Access Journals (Sweden)

    Guillermo Aranda

    Full Text Available Spawning behaviour of Atlantic bluefin tuna (Thunnus thynnus was investigated using electronic satellite tags deployed in the western Mediterranean spawning ground, around the Balearic Islands (years 2009-2011. All the fish were tagged underwater and released within schools. In general, the fish tagged in the same year/school displayed common migratory trends. Following extended residency around the Balearic Islands, most tagged tuna crossed the Strait of Gibraltar heading for the North Atlantic. Discrepancies between the migratory tracks reconstructed from this and previous electronic tagging studies suggest that the bluefin tuna Mediterranean population may comprise distinct units exhibiting differing migratory behaviours. The diving behaviour varied between oceanic regions throughout the migratory pathways, the shallowest distribution taking place in the spawning ground and the deepest at the Strait of Gibraltar. A unique diving pattern was found on the majority of nights while the fish stayed at the spawning ground; it consisted of frequent and brief oscillatory movements up and down through the mixed layer, resulting in thermal profiles characterized by oscillations about the thermocline. Such a pattern is believed to reflect recent courtship and spawning activity. Reproductive parameters inferred from the analysis of vertical profiles are consistent with those estimated in previous studies based on biological samples.

  20. Spawning behaviour and post-spawning migration patterns of atlantic bluefin tuna (Thunnus thynnus) ascertained from satellite archival tags.

    Science.gov (United States)

    Aranda, Guillermo; Abascal, Francisco Javier; Varela, José Luis; Medina, Antonio

    2013-01-01

    Spawning behaviour of Atlantic bluefin tuna (Thunnus thynnus) was investigated using electronic satellite tags deployed in the western Mediterranean spawning ground, around the Balearic Islands (years 2009-2011). All the fish were tagged underwater and released within schools. In general, the fish tagged in the same year/school displayed common migratory trends. Following extended residency around the Balearic Islands, most tagged tuna crossed the Strait of Gibraltar heading for the North Atlantic. Discrepancies between the migratory tracks reconstructed from this and previous electronic tagging studies suggest that the bluefin tuna Mediterranean population may comprise distinct units exhibiting differing migratory behaviours. The diving behaviour varied between oceanic regions throughout the migratory pathways, the shallowest distribution taking place in the spawning ground and the deepest at the Strait of Gibraltar. A unique diving pattern was found on the majority of nights while the fish stayed at the spawning ground; it consisted of frequent and brief oscillatory movements up and down through the mixed layer, resulting in thermal profiles characterized by oscillations about the thermocline. Such a pattern is believed to reflect recent courtship and spawning activity. Reproductive parameters inferred from the analysis of vertical profiles are consistent with those estimated in previous studies based on biological samples.

  1. Effects of habitat features on size-biased predation on salmon by bears.

    Science.gov (United States)

    Andersson, Luke C; Reynolds, John D

    2017-05-01

    Predators can drive trait divergence among populations of prey by imposing differential selection on prey traits. Habitat characteristics can mediate predator selectivity by providing refuge for prey. We quantified the effects of stream characteristics on biases in the sizes of spawning salmon caught by bears (Ursus arctos and U. americanus) on the central coast of British Columbia, Canada by measuring size-biased predation on spawning chum (Oncorhynchus keta) and pink (O. gorbuscha) salmon in 12 streams with varying habitat characteristics. We tested the hypotheses that bears would catch larger than average salmon (size-biased predation) and that this bias toward larger fish would be higher in streams that provide less protection to spawning salmon from predation (e.g., less pools, wood, undercut banks). We then we tested for how such size biases in turn translate into differences among populations in the sizes of the fish. Bears caught larger-than-average salmon as the spawning season progressed and as predicted, this was most pronounced in streams with fewer refugia for the fish (i.e., wood and undercut banks). Salmon were marginally smaller in streams with more pronounced size-biased predation but this predictor was less reliable than physical characteristics of streams, with larger fish in wider, deeper streams. These results support the hypothesis that selective forces imposed by predators can be mediated by habitat characteristics, with potential consequences for physical traits of prey.

  2. Grande Ronde Basin Spring Chinook Salmon Captive Broodstock Program, 1995-2002 Summary Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hoffnagle, Timothy; Carmichael, Richard; Noll, William

    2003-12-01

    survey areas in 1995 from as high as 1,205 redds in the same area in 1969 (Table 1). All streams reached low points (0-6 redds in the index areas) in the 1990's, except those in which no redds were found for several years and surveys were discontinued, such as Spring, Sheep and Indian creeks which had a total of 109 redds in 1969. The Minam and Wenaha rivers are tributaries of the Grande Ronde River located primarily in wilderness areas. Chinook salmon numbers in these two streams (based on redd counts) also decreased dramatically beginning in the early 1970's (Table 1). Since then there have been a few years of increasing numbers of redds but counts have generally been 25-40% of the number seen in the 1960's. No hatchery fish have been released into either of these streams and we monitor them during spawning ground surveys for the presence of hatchery strays. These populations will be used as a type of control for evaluating our supplementation efforts in Catherine Creek, upper Grande Ronde River and Lostine River. In this way, we can attempt to filter out the effects of downstream variables, over which we have no control, when we interpret the results of the captive broodstock program as the F1 and F2 generations spawn and complete their life cycles in the wild. The Grande Ronde Basin Captive Broodstock Program was initiated because these chinook salmon populations had reached critical levels where dramatic and unprecedented efforts were needed to prevent extinction and preserve any future options for use of endemic fish for artificial propagation programs for recovery and mitigation. This program was designed to quickly increase numbers of returning adults, while maintaining the genetic integrity of each endemic population.

  3. 1992 Columbia River Salmon Flow Measures Options Analysis/EIS.

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This Options Analysis/Environmental Impact Statement (OA/EIS) identifies, presents effects of, and evaluates the potential options for changing instream flow levels in efforts to increase salmon populations in the lower Columbia and Snake rivers. The potential actions would be implemented during 1992 to benefit juvenile and adult salmon during migration through eight run-of-river reservoirs. The Corps of Engineers (Corps) prepared this document in cooperation with the Bonneville Power Administration and the Bureau of Reclamation. The US Fish and Wildlife Service (FSWS) is a participating agency. The text and appendices of the document describe the characteristics of 10 Federal projects and one private water development project in the Columbia River drainage basin. Present and potential operation of these projects and their effects on the salmon that spawn and rear in the Columbia and Snake River System are presented. The life history, status, and response of Pacific salmon to current environmental conditions are described.

  4. 1992 Columbia River salmon flow measures Options Analysis/EIS

    International Nuclear Information System (INIS)

    1992-01-01

    This Options Analysis/Environmental Impact Statement (OA/EIS) identifies, presents effects of, and evaluates the potential options for changing instream flow levels in efforts to increase salmon populations in the lower Columbia and Snake rivers. The potential actions would be implemented during 1992 to benefit juvenile and adult salmon during migration through eight run-of-river reservoirs. The Corps of Engineers (Corps) prepared this document in cooperation with the Bonneville Power Administration and the Bureau of Reclamation. The US Fish and Wildlife Service (FSWS) is a participating agency. The text and appendices of the document describe the characteristics of 10 Federal projects and one private water development project in the Columbia River drainage basin. Present and potential operation of these projects and their effects on the salmon that spawn and rear in the Columbia and Snake River System are presented. The life history, status, and response of Pacific salmon to current environmental conditions are described

  5. Enhanced incubation success for kokanee spawning in groundwater upwelling sites in a small Idaho stream

    Science.gov (United States)

    James W. Garrett; David H. Bennett; Frank O. Frost; Russell F. Thurow

    1998-01-01

    Kokanee (Oncorhynchus nerka lacustrine sockeye salmon) spawned in groundwater upwelling in the North Fork of the Payette River, Idaho. Intragravel water temperatures in groundwater-influenced redds exceeded surface flow water temperature by 2.4–2.6°C. In redds without groundwater influence, intragravel and water column temperatures did not differ by more than 0.2°C....

  6. Multiscale hydrogeomorphic influences on bull trout (Salvelinus confluentus) spawning habitat

    Science.gov (United States)

    Bean, Jared R; Wilcox, Andrew C.; Woessner, William W.; Muhlfeld, Clint C.

    2015-01-01

    We investigated multiscale hydrogeomorphic influences on the distribution and abundance of bull trout (Salvelinus confluentus) spawning in snowmelt-dominated streams of the upper Flathead River basin, northwestern Montana. Within our study reaches, bull trout tended to spawn in the finest available gravel substrates. Analysis of the mobility of these substrates, based on one-dimensional hydraulic modeling and calculation of dimensionless shear stresses, indicated that bed materials in spawning reaches would be mobilized at moderate (i.e., 2-year recurrence interval) high-flow conditions, although the asynchronous timing of the fall–winter egg incubation period and typical late spring – early summer snowmelt high flows in our study area may limit susceptibility to redd scour under current hydrologic regimes. Redd occurrence also tended to be associated with concave-up bedforms (pool tailouts) with downwelling intragravel flows. Streambed temperatures tracked stream water diurnal temperature cycles to a depth of at least 25 cm, averaging 6.1–8.1 °C in different study reaches during the spawning period. Ground water provided thermal moderation of stream water for several high-density spawning reaches. Bull trout redds were more frequent in unconfined alluvial valley reaches (8.5 versus 5.0 redds·km−1 in confined valley reaches), which were strongly influenced by hyporheic and groundwater – stream water exchange. A considerable proportion of redds were patchily distributed in confined valley reaches, however, emphasizing the influence of local physical conditions in supporting bull trout spawning habitat. Moreover, narrowing or “bounding” of these alluvial valley segments did not appear to be important. Our results suggest that geomorphic, thermal, and hydrological factors influence bull trout spawning occurrence at multiple spatial scales.

  7. Wild Steelhead and introduced spring Chinook Salmon in the Wind River, Washington: Overlapping populations and interactions

    Science.gov (United States)

    Jezorek, I.G.; Connolly, P.J.

    2010-01-01

    We investigated interactions of introduced juvenile spring Chinook salmon Oncorhynchus tshawytscha with wild juvenile steelhead O. mykiss in the upper Wind River watershed (rkm 24.6 to rkm 43.8), Washington. Our objective was to determine if the presence of introduced spring Chinook salmon influenced populations of wild juvenile steelhead and if other biotic or abiotic factors influenced distribution and populations of these species. We snorkeled to assess distribution and abundance in one to six stream reaches per year during 2001 through 2007. Juvenile steelhead were found in each sampled reach each year, but juvenile Chinook salmon were not. The upstream extent of distribution of juvenile Chinook salmon varied from rkm 29.7 to 42.5. Our analyses suggest that juvenile Chinook salmon distribution was much influenced by flow during the spawning season. Low flow appeared to limit access of escaped adult Chinook salmon to upper stream reaches. Abundance of juvenile Chinook salmon was also influenced by base flow during the previous year, with base flow occurring post spawn in late August or early September. There were no relationships between juvenile Chinook salmon abundance and number of Chinook salmon spawners, magnitude of winter flow that might scour redds, or abundance of juvenile steelhead. Abundance of age-0 steelhead was influenced primarily by the number of steelhead spawners the previous year, and abundance of age-1 steelhead was influenced primarily by abundance of age-0 steelhead the previous year. Juvenile steelhead abundance did not show a relationship with base or peak flows, nor with number of escaped Chinook salmon adults during the previous year. We did not detect a negative influence of the relatively low abundance of progeny of escaped Chinook salmon on juvenile steelhead abundance. This low abundance of juvenile Chinook salmon was persistent throughout our study and is likely a result of hatchery management and habitat conditions. Should one or

  8. Ecological, morphological, genetic and life history characteristics of two sockeye salmon populations, Tustumena Lake, Alaska

    Science.gov (United States)

    Woody, Carol Ann

    1998-01-01

    Populations can differ in both phenotypic and molecular genetic traits. Phenotypic differences likely result from differential selection pressures in the environment, whereas differences in neutral molecular markers result from genetic drift associated with some degree of reproductive isolation. Two sockeye salmon, Oncorhynchus nerka, populations were compared using both phenotypic and genotypic characters, and causal factors were examined. Salmon spawning in a short (salmon spawning in a longer (∼80 km), deeper, stained, diverse, precipitation-dominated stream. Run timing differences were associated with differences in stream thermal regimes. Age and size at maturity differences are likely due to differences in age-specific mortality rates. Fish in the shallow spring-fed system suffered higher adult predation rates and exhibited greater egg to fry survival compared to fish in the precipitation-fed system. Salmon in both streams exhibited non-random nest site selection for deeper habitats and smaller substrates (≥2 to Genetic comparisons of six microsatellite loci indicated that run time was a more effective reproductive isolating mechanism than geographical distance. Differences between and within the tributary spawning populations are discussed in terms of selection, genetic drift, and the homogenizing effects of gene flow. This study indicates important adaptive differences may exist between proximate spawning groups of salmon which should be considered when characterizing populations for conservation or management purposes.

  9. Predictions of realised fecundity and spawning time in Norwegian spring-spawning herring ( Clupea harengus)

    Science.gov (United States)

    Óskarsson, G. J.; Kjesbu, O. S.; Slotte, A.

    2002-08-01

    Maturing Norwegian spring-spawning (NSS) herring, Clupea harengus, were collected for reproductive analyses along the Norwegian coast prior to the spawning seasons of 1997-2000. Over this time period there was a marked change in weight (W) at length (TL) with 1998 showing extremely low values and 2000 high values in a historical perspective. Potential fecundity, amounting to about 20 000-100 000 developing (vitellogenic) oocytes per fish and positively related to fish size, increased significantly with fish condition. Relative somatic potential fecundity (RF P, number of oocytes per g ovary-free body weight) in NSS herring was found to vary by 35-55% between years. Unexpectedly, females in 2000 showed low RF P-values, possibly due to negative feedback from previous reproductive investments at low condition. A clear threshold value for Fulton's condition factor, K (K=100×W/TL 3), of 0.65-0.70 existed below which there was considerable atresia (resorption of vitellogenic oocytes). Thus, these components of the spawning stock, amounting to 1-46% in the period 1980-1999, obviously contributed relatively little to the total egg production. This was confirmed by low ovary weights and examples of delayed oocyte development in these individuals. An up-to-date atresia model is presented. The established oocyte growth curve, and to a lesser degree the assumed atretic oocytic turnover rate, was critical for the estimation of realised fecundity (number of eggs spawned). Modelled realised fecundity was significantly below observed potential fecundity. Females that had migrated the shortest distance from the over-wintering area, Vestfjorden, northern Norway, were in the poorest condition, had the least developed oocytes and the lowest potential and realised fecundities. In agreement with previously published studies on temporal and spatial changes in gonad weights, those females reaching the main spawning grounds in the south-western part of the coast (Møre) were the most

  10. Sexual difference in PCB concentrations of coho salmon (Oncorhynchus kisutch)

    Science.gov (United States)

    Madenjian, Charles P.; Schrank, Candy S.; Begnoche, Linda J.; Elliott, Robert F.; Quintal, Richard T.

    2010-01-01

    We determined polychlorinated biphenyl (PCB) concentrations in 35 female coho salmon (Oncorhynchus kisutch) and 60 male coho salmon caught in Lake Michigan (Michigan and Wisconsin, United States) during the fall of 1994 and 1995. In addition, we determined PCB concentrations in the skin-on fillets of 26 female and 19 male Lake Michigan coho salmon caught during the fall of 2004 and 2006. All coho salmon were age-2 fish. These fish were caught prior to spawning, and therefore release of eggs could not account for sexual differences in PCB concentrations because female coho salmon spawn only once during their lifetime. To investigate whether gross growth efficiency (GGE) differed between the sexes, we applied bioenergetics modeling. Results showed that, on average, males were 19% higher in PCB concentration than females, based on the 1994–1995 dataset. Similarly, males averaged a 20% higher PCB concentration in their skin-on fillets compared with females. According to the bioenergetics modeling results, GGE of adult females was less than 1% higher than adult male GGE. Thus, bioenergetics modeling could not explain the 20% higher PCB concentration exhibited by the males. Nonetheless, a sexual difference in GGE remained a plausible explanation for the sexual difference in PCB concentrations.

  11. Wild Steelhead Studies, Salmon and Clearwater Rivers, 1994 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Holubetz, Terry B; Leth, Brian D.

    1997-05-01

    To enumerate chinook salmon Oncorhynchus tshawytscha and steelhead O. mykiss adult escapements, weirs were operated in Marsh, Chamberlain, West Fork Chamberlain, and Running creeks. Beginning in late July 1994, a juvenile trap was installed in Running Creek to estimate juvenile outmigrants. Plans have been completed to install a weir in Rush Creek to enumerate steelhead adult escapement beginning in spring 1995. Design and agreements are being developed for Johnson Creek and Captain John Creek. Data collected in 1993 and 1994 indicate that spring chinook salmon and group-B steelhead populations and truly nearing extinction levels. For example, no adult salmon or steelhead were passed above the West Fork Chamberlain Creek weir in 1984, and only 6 steelhead and 16 chinook salmon were passed into the important spawning area on upper Marsh Creek. Group-A steelhead are considerably below desirable production levels, but in much better status than group-B stocks. Production of both group-A and group-B steelhead is being limited by low spawning escapements. Studies have not been initiated on wild summer chinook salmon stocks.

  12. Snake River sockeye salmon (Oncorhynchus nerka) habitat/limnologic research

    International Nuclear Information System (INIS)

    Spaulding, S.

    1993-05-01

    This report outlines long-term planning and monitoring activities that occurred in 1991 and 1992 in the Stanley Basin Lakes of the upper Salmon River, Idaho for the purpose of sockeye salmon nerka) recovery. Limnological monitoring and experimental sampling protocol, designed to establish a limnological baseline and to evaluate sockeye salmon production capability of the lakes, are presented. Also presented are recommended passage improvements for current fish passage barriers/impediments on migratory routes to the lakes. We initiated O. nerka population evaluations for Redfish and Alturas lakes; this included population estimates of emerging kokanee fry entering each lake in the spring and adult kokanee spawning surveys in tributary streams during the fall. Gill net evaluations of Alturas, Pettit, and Stanley lakes were done in September, 1992 to assess the relative abundance of fish species among the Stanley Basin lakes. Fish population data will be used to predict sockeye salmon production potential within a lake, as well as a baseline to monitor long-term fish community changes as a result of sockeye salmon recovery activities. Also included is a paper that reviews sockeye salmon enhancement activities in British Columbia and Alaska and recommends strategies for the release of age-0 sockeye salmon that will be produced from the current captive broodstock

  13. New insight into the spawning behavior of lake trout, Salvelinus namaycush, from a recovering population in the Laurentian Great Lakes

    Science.gov (United States)

    Binder, Thomas R.; Thompson, Henry T.; Muir, Andrew M.; Riley, Stephen C.; Marsden, J. Ellen; Bronte, Charles R.; Krueger, Charles C.

    2015-01-01

    Spawning behavior of lake trout, Salvelinus namaycush, is poorly understood, relative to stream-dwelling salmonines. Underwater video records of spawning in a recovering population from the Drummond Island Refuge (Lake Huron) represent the first reported direct observations of lake trout spawning in the Laurentian Great Lakes. These observations provide new insight into lake trout spawning behavior and expand the current conceptual model. Lake trout spawning consisted of at least four distinct behaviors: hovering, traveling, sinking, and gamete release. Hovering is a new courtship behavior that has not been previously described. The apparent concentration of hovering near the margin of the spawning grounds suggests that courtship and mate selection might be isolated from the spawning act (i.e., traveling, sinking, and gamete release). Moreover, we interpret jockeying for position displayed by males during traveling as a unique form of male-male competition that likely evolved in concert with the switch from redd-building to itinerant spawning in lake trout. Unlike previous models, which suggested that intra-sexual competition and mate selection do not occur in lake trout, our model includes both and is therefore consistent with evolutionary theory, given that the sex ratio on spawning grounds is skewed heavily towards males. The model presented in this paper is intended as a working hypothesis, and further revision may become necessary as we gain a more complete understanding of lake trout spawning behavior.

  14. Snake River Sockeye Salmon Habitat and Limnological Research; 2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Andre E.; Taki, Doug (Shoshone-Bannock Tribes, Fort Hall, ID); Griswold, Robert G. (Biolines, Stanley, ID)

    2004-06-01

    In March 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list the Snake River sockeye salmon (Oncorhynchus nerka) as endangered. Snake River sockeye salmon were officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991, the Snake River Sockeye Salmon Habitat and Limnological Research Program was implemented (Project Number 1991-071-00). This project is part of an interagency effort to prevent the extinction of the Redfish Lake stock of sockeye salmon. The Shoshone-Bannock Tribal goal for this project is two tiered: The immediate goal is to increase the population of Snake River sockeye salmon while preserving the unique genetic characteristics of the Evolutionarily Significant Unit (ESU); The Tribe's long term goal is to maintain a viable population that warrants delisting and provides Tribal harvest opportunities. The Bonneville Power Administration (BPA) provides funding for this interagency recovery program through their Integrated Fish and Wildlife Program. Collaborators in the recovery effort include the National Oceanic and Atmospheric Administration (NOAA), the Idaho Department of Fish and Game (IDFG), the University of Idaho (UI), and the Shoshone-Bannock Tribes (SBT). This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the 2004 calendar year. Project tasks include: (1) monitor limnological parameters of the Sawtooth Valley lakes to assess lake productivity; (2) conduct lake fertilization in Pettit Lake; (3) reduce the number of mature kokanee salmon spawning in Fishhook Creek; (4) monitor and enumerate sockeye salmon smolt migration from Pettit and Alturas lakes; (5) monitor spawning kokanee salmon escapement and estimate fry recruitment in Fishhook, Alturas Lake, and Stanley Lake creeks; (6) conduct sockeye salmon and kokanee salmon population surveys; (7) evaluate potential competition and predation

  15. Migration patterns of post-spawning Pacific herring in a subarctic sound

    Science.gov (United States)

    Bishop, Mary Anne; Eiler, John H.

    2018-01-01

    Understanding the distribution of Pacific herring (Clupea pallasii) can be challenging because spawning, feeding and overwintering may take place in different areas separated by 1000s of kilometers. Along the northern Gulf of Alaska, Pacific herring movements after spring spawning are largely unknown. During the fall and spring, herring have been seen moving from the Gulf of Alaska into Prince William Sound, a large embayment, suggesting that fish spawning in the Sound migrate out into the Gulf of Alaska. We acoustic-tagged 69 adult herring on spawning grounds in Prince William Sound during April 2013 to determine seasonal migratory patterns. We monitored departures from the spawning grounds as well as herring arrivals and movements between the major entrances connecting Prince William Sound and the Gulf of Alaska. Departures of herring from the spawning grounds coincided with cessation of major spawning events in the immediate area. After spawning, 43 of 69 tagged herring (62%) moved to the entrances of Prince William Sound over a span of 104 d, although most fish arrived within 10 d of their departure from the spawning grounds. A large proportion remained in these areas until mid-June, most likely foraging on the seasonal bloom of large, Neocalanus copepods. Pulses of tagged herring detected during September and October at Montague Strait suggest that some herring returned from the Gulf of Alaska. Intermittent detections at Montague Strait and the Port Bainbridge passages from September through early January (when the transmitters expired) indicate that herring schools are highly mobile and are overwintering in this area. The pattern of detections at the entrances to Prince William Sound suggest that some herring remain in the Gulf of Alaska until late winter. The results of this study confirm the connectivity between local herring stocks in Prince William Sound and the Gulf of Alaska.

  16. Founding events influence genetic population structure of sockeye salmon (Oncorhynchus nerka) in Lake Clark, Alaska

    Science.gov (United States)

    Ramstad, K.M.; Woody, C.A.; Sage, G.K.; Allendorf, F.W.

    2004-01-01

    Bottlenecks can have lasting effects on genetic population structure that obscure patterns of contemporary gene flow and drift. Sockeye salmon are vulnerable to bottleneck effects because they are a highly structured species with excellent colonizing abilities and often occupy geologically young habitats. We describe genetic divergence among and genetic variation within spawning populations of sockeye salmon throughout the Lake Clark area of Alaska. Fin tissue was collected from sockeye salmon representing 15 spawning populations of Lake Clark, Six-mile Lake, and Lake Iliamna. Allele frequencies differed significantly at 11 microsatellite loci in 96 of 105 pairwise population comparisons. Pairwise estimates of FST ranged from zero to 0.089. Six-mile Lake and Lake Clark populations have historically been grouped together for management purposes and are geographically proximate. However, Six-mile Lake populations are genetically similar to Lake Iliamna populations and are divergent from Lake Clark populations. The reduced allelic diversity and strong divergence of Lake Clark populations relative to Six-mile Lake and Lake Iliamna populations suggest a bottleneck associated with the colonization of Lake Clark by sockeye salmon. Geographic distance and spawning habitat differences apparently do not contribute to isolation and divergence among populations. However, temporal isolation based on spawning time and founder effects associated with ongoing glacial retreat and colonization of new spawning habitats contribute to the genetic population structure of Lake Clark sock-eye salmon. Nonequilibrium conditions and the strong influence of genetic drift caution against using estimates of divergence to estimate gene flow among populations of Lake Clark sockeye salmon.

  17. Domestic cultivation of salmon in the Pacific Northwest and aquaculture of Malaysian prawns in controlled environments

    Energy Technology Data Exchange (ETDEWEB)

    Friedman, B.A.; Sandifer, P.A.; Smith, T.I.J.

    1978-07-01

    Aquaculture of salmon and shrimp is discussed. Domsea Farms in the Pacific Northwest has facilities for spawning, hatching, and rearing of coho salmon for U.S. markets. Health management programs operate to keep salmon free from bacterial or viral diseases. Recent developments in technology for the intensive culture of a tropical prawn (Macrobrachium rosenbergii) are considered. Commercial facilities in South Carolina consisting of hatchery, nursery, production, and brood stock phases are described. Designs for very intensive grow-out systems include small earthen pond units, modified Shigueno-type tanks, and aquacells. Major problem areas of commercial shrimp production are identified. (10 diagrams, 1 graph, 11 photos, numerous references)

  18. Spatiotemporal patterns and habitat associations of smallmouth bass (Micropterus dolomieu) invading salmon-rearing habitat

    Science.gov (United States)

    Lawrence, David J.; Olden, Julian D.; Torgersen, Christian E.

    2012-01-01

    1. Smallmouth bass (Micropterus dolomieu) have been widely introduced to fresh waters throughout the world to promote recreational fishing opportunities. In the Pacific Northwest (U.S.A.), upstream range expansions of predatory bass, especially into subyearling salmon-rearing grounds, are of increasing conservation concern, yet have received little scientific inquiry. Understanding the habitat characteristics that influence bass distribution and the timing and extent of bass and salmon overlap will facilitate the development of management strategies that mitigate potential ecological impacts of bass.2. We employed a spatially continuous sampling design to determine the extent of bass and subyearling Chinook salmon (Oncorhynchus tshawytscha) sympatry in the North Fork John Day River (NFJDR), a free-flowing river system in the Columbia River Basin that contains an upstream expanding population of non-native bass. Extensive (i.e. 53 km) surveys were conducted over 2 years and during an early and late summer period of each year, because these seasons provide a strong contrast in the river’s water temperature and flow condition. Classification and regression trees were applied to determine the primary habitat correlates of bass abundance at reach and channel-unit scales.3. Our study revealed that bass seasonally occupy up to 22% of the length of the mainstem NFJDR where subyearling Chinook salmon occur, and the primary period of sympatry between these species was in the early summer and not during peak water temperatures in late summer. Where these species co-occurred, bass occupied 60–76% of channel units used by subyearling Chinook salmon in the early summer and 28–46% of the channel units they occupied in the late summer. Because these rearing salmon were well below the gape limitation of bass, this overlap could result in either direct predation or sublethal effects of bass on subyearling Chinook salmon. The upstream extent of bass increased 10–23

  19. Net ground speed of downstream migrating radio-tagged Atlantic salmon ( Salmo salar L.) and brown trout ( Salmo trutta L.) smolts in relation to environmental factors

    DEFF Research Database (Denmark)

    Aarestrup, Kim; Nielsen, C.; Koed, Anders

    2002-01-01

    tagged and released in the Danish River Lilleaa. The downstream migration of the different groups of fish was monitored by manual tracking and by three automatic listening stations. The downstream migration of radio tagged smolts of both species occurred concurrently with their untagged counterparts...... of the different groups. The migration speed of wild sea trout smolts was positively correlated with water discharge in both years. In F1 sea trout smolts, migration speed was positively correlated with temperature in 1999. The migration speed of salmon smolts did not correlate to any of the investigated...

  20. Post-mortem sporulation of Ceratomyxa shasta (Myxozoa) after death in adult Chinook salmon

    Science.gov (United States)

    Kent, Michael L.; Soderlund, K.; Thomann, E.; Schreck, Carl B.; Sharpton, T.J.

    2014-01-01

    Ceratomyxa shasta (Myxozoa) is a common gastrointestinal pathogen of salmonid fishes in the Pacific Northwest of the United States. We have been investigating this parasite in adult Chinook salmon (Oncorhynchus tshawytscha) in the Willamette River, Oregon. In prior work, we observed differences in the pattern of development of C. shasta in adult salmon compared to juvenile salmon. Adult salmon consistently had large numbers of prespore stages in many of the fish that survived to spawn in the fall. However, myxospores were rarely observed, even though they were exposed and presumably infected for months before spawning. We evaluated the ability of C. shasta to sporulate following fish death because it is reported that myxosores are common in carcasses of Chinook salmon. We collected the intestine from 30 adult salmon immediately after artificial spawning and death (T0). A total of 23 fish were infected with C. shasta based on histology, but only a few myxospores were observed in 1 fish by histology. Intestines of these fish were examined at T0 and T7 (latter held at 17 C for 7 days) using quantified wet mount preparations. An increase in myxospore concentrations was seen in 39% of these fish, ranging between a 1.5- to a 14.5-fold increase. The most heavily infected fish exhibited a 4.6-fold increase from 27,841 to 129,352 myxospores/cm. This indicates, supported by various statistical analyses, that under certain conditions presporogonic forms are viable and continue to sporulate after death in adult salmon. Considering the life cycle of C. shasta and anadromous salmon, the parasite may have evolved 2, non-mutually exclusive developmental strategies. In young fish (parr and smolts), the parasite sporulates shortly after infection and is released into freshwater from either live or dead fish before their migration to seawater, where the alternate host is absent. The second strategy occurs in adult salmon, particularly spring Chinook salmon, which become infected upon

  1. Determination of Swimming Speeds and Energetic Demands of Upriver Migrating Fall Chinook Salmon (Oncorhynchus Tshawytscha) in the Klickitat River, Washington.

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Richard S.; Geist, David R.; Confederated Tribes and Bands of the Yakama Nation, Washington

    2002-08-30

    passing waterfalls than males. The study also examined energy costs and swimming speeds for fish released above Lyle Falls as they migrated to upstream spawning areas. This journey averaged 15.93 days to travel a mean maximum of 37.6 km upstream at a total energy cost of approx 3,971 kcals (34% anaerobic and 66% aerobic) for a sample of five fish. A bioenergetics example was run, which estimated that fall chinook salmon would expend an estimated 1,208 kcal to pass from the mouth of the Columbia River to Bonneville Dam and 874 kcals to pass Bonneville Dam and pool and the three falls on the Lower Klickitat River, plus an additional 2,770 kcals above the falls to reach the spawning grounds, leaving them with approximately 18% (1,089 kcals) of their original energy reserves for spawning. Results of the bioenergetics example suggest that a delay of 9 to 11 days along the lower Klickitat River may deplete their remaining energy reserves (at a rate of about 105 kcal d{sup -1}) resulting in death before spawning would occur.

  2. Timing games in the reproductive phenology of female Pacific salmon (Oncorhynchus spp.)

    NARCIS (Netherlands)

    Morbey, Y.E.; Ydenberg, R.C.

    2003-01-01

    We use a game-theoretic framework to investigate the reproductive phenology of female kokanee (Oncorhynchus nerka). As in the other semelparous species of Pacific salmon, females construct nests in gravel, spawn with males, bury their fertilized eggs, and defend their nest sites until they die

  3. Thermal regime, predation danger and the early marine exit of sockeye salmon Oncorhynchus nerka

    NARCIS (Netherlands)

    Katinic, P.J.; Patterson, D.A.; Ydenberg, R.C.

    2015-01-01

    Marine exit timing of sockeye salmon Oncorhynchus nerka populations on the Haida Gwaii Archipelago, British Columbia, Canada, is described, with specific focus on Copper Creek. Marine exit in Copper Creek occurs¿>¿130¿days prior to spawning, one of the longest adult freshwater residence periods

  4. Larval growth and drift pattern and the separation of herring spawning groups in the North Sea

    DEFF Research Database (Denmark)

    Munk, Peter; Christensen, Villy

    1990-01-01

    Yorkshire is evident from distributions of newly hatched herring larvae. The dramatic changes in relative importance of spawning grounds are traced in the data on both late larvae (6 months old) and juveniles (18 months old). The onset of extended spawning off Buchan and off Yorkshire was followed...... by increase in distinct groups of late larvae of large mean length, and by enlargement of a group of medium-sized juveniles. It is hypothesized that the identified groups are interconnected. Thus, larvae spawned off Buchan and off Yorkshire are found to have growth rates superior to those attained by larvae...

  5. Snake River Sockeye Salmon Habitat and Limnological Research : 2008 Annual Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Andre E. [Shoshone-Bannock Tribes; Griswold, Robert G. [Biolines Environmental Consulting; Taki, Doug [Shoshone-Bannock Tribes

    2009-07-31

    In March 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list Snake River sockeye salmon (Oncorhynchus nerka) as endangered. Snake River sockeye salmon were officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991, the Snake River Sockeye Salmon Habitat and Limnological Research Project was implemented. This project is part of an interagency effort to prevent the extinction of the Redfish Lake stock of Snake River sockeye salmon. The Shoshone-Bannock Tribal goal for this project is two tiered: the immediate goal is to increase the population of Snake River sockeye salmon while preserving the unique genetic characteristics of the evolutionarily significant unit (ESU). The Tribes long term goal is to maintain a viable population that warrants delisting and provides Tribal harvest opportunities. The Bonneville Power Administration (BPA) provides funding for this interagency Recovery effort. Collaborators in the recovery effort include the National Oceanic and Atmospheric Administration (NOAA), the Idaho Department of Fish and Game (IDFG), the University of Idaho (UI), and the Shoshone-Bannock Tribes (SBT). This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the 2008 calendar year. Project tasks include: (1) monitor limnological parameters of the Sawtooth Valley lakes to assess lake productivity; (2) conduct lake fertilization in Pettit and Alturas lakes; (3) reduce the number of mature kokanee salmon spawning in Alturas Lake Creek; (4) monitor, enumerate, and evaluate sockeye salmon smolt migration from Pettit and Alturas lakes; (5) monitor spawning kokanee salmon escapement and estimate fry recruitment in Fishhook and Alturas Lake creeks; (6) conduct sockeye and kokanee salmon population surveys; (7) evaluate potential competition and predation between stocked juvenile sockeye salmon and a variety of fish species in

  6. Fuzzy modelling of Atlantic salmon physical habitat

    Science.gov (United States)

    St-Hilaire, André; Mocq, Julien; Cunjak, Richard

    2015-04-01

    Fish habitat models typically attempt to quantify the amount of available river habitat for a given fish species for various flow and hydraulic conditions. To achieve this, information on the preferred range of values of key physical habitat variables (e.g. water level, velocity, substrate diameter) for the targeted fishs pecies need to be modelled. In this context, we developed several habitat suitability indices sets for three Atlantic salmon life stages (young-of-the-year (YOY), parr, spawning adults) with the help of fuzzy logic modeling. Using the knowledge of twenty-seven experts, from both sides of the Atlantic Ocean, we defined fuzzy sets of four variables (depth, substrate size, velocity and Habitat Suitability Index, or HSI) and associated fuzzy rules. When applied to the Romaine River (Canada), median curves of standardized Weighted Usable Area (WUA) were calculated and a confidence interval was obtained by bootstrap resampling. Despite the large range of WUA covered by the expert WUA curves, confidence intervals were relatively narrow: an average width of 0.095 (on a scale of 0 to 1) for spawning habitat, 0.155 for parr rearing habitat and 0.160 for YOY rearing habitat. When considering an environmental flow value corresponding to 90% of the maximum reached by WUA curve, results seem acceptable for the Romaine River. Generally, this proposed fuzzy logic method seems suitable to model habitat availability for the three life stages, while also providing an estimate of uncertainty in salmon preferences.

  7. Research and Recovery of Snake River Sockeye Salmon, 1994-1995 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Keith A.

    1996-09-01

    In 1991, the National Marine Fisheries Service (NMFS) listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. Initial steps to recover the species include the establishment of captive broodstocks at the Idaho Department of Fish and Game (IDFG) Eagle Fish Hatchery in Eagle, Idaho. Research and recovery activities for sockeye salmon conducted by IDFG during the period of April 1994 to April 1995 are covered by this report. One female anadromous adult returned to the Redfish Lake Creek trap this year. She was spawned at Eagle Fish Hatchery on October 21, 1994. Her fecundity was 2,896. The mean fertilization rate and percent swim-up were 96% and 95%, respectively. Four hundred eighty eyed eggs were shipped to the NMFS Big Beef Creek Fish Hatchery in Washington state, leaving 2,028 fish on site at Eagle. Additionally, captive broodstock and wild residual sockeye salmon (captured at Redfish Lake) were spawned. Spawning data from 234 females spawned during this period are included in this report. Other spawning data (i.e., genetic cross and incubation temperature) are included in the Captive Broodstock Research section of this report.

  8. Escapement and Productivity of Spring Chinook Salmon and Summer Steelhead in the John Day River Basin, 2005-2006 Annual Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Terra Lang; Wilson, Wayne H.; Ruzycki, James R. [Oregon Department of Fish and Wildlife

    2009-04-10

    The objectives are: (1) Estimate number and distribution of spring Chinook salmon Oncorhynchus tshawytscha redds and spawners in the John Day River subbasin; and (2) Estimate smolt-to-adult survival rates (SAR) and out-migrant abundance for spring Chinook and summer steelhead O. mykiss and life history characteristics of summer steelhead. The John Day River subbasin supports one of the last remaining intact wild populations of spring Chinook salmon and summer steelhead in the Columbia River Basin. These populations, however, remain depressed relative to historic levels. Between the completion of the life history and natural escapement study in 1984 and the start of this project in 1998, spring Chinook spawning surveys did not provide adequate information to assess age structure, progeny-to-parent production values, smolt-to-adult survival (SAR), or natural spawning escapement. Further, only very limited information is available for steelhead life history, escapement, and productivity measures in the John Day subbasin. Numerous habitat protection and rehabilitation projects to improve salmonid freshwater production and survival have also been implemented in the basin and are in need of effectiveness monitoring. While our monitoring efforts outlined here will not specifically measure the effectiveness of any particular project, they will provide much needed background information for developing context for project-specific effectiveness monitoring efforts. To meet the data needs as index stocks, to assess the long-term effectiveness of habitat projects, and to differentiate freshwater and ocean survival, sufficient annual estimates of spawner escapement, age structure, SAR, egg-to-smolt survival, smolt-per-redd ratio, and freshwater habitat use are essential. We have begun to meet this need through spawning ground surveys initiated for spring Chinook salmon in 1998 and smolt PIT-tagging efforts initiated in 1999. Additional sampling and analyses to meet these goals

  9. Kodiak brown bears surf the salmon red wave: direct evidence from GPS collared individuals.

    Science.gov (United States)

    Deacy, William; Leacock, William; Armstrong, Jonathan B; Stanford, Jack A

    2016-05-01

    A key constraint faced by consumers is achieving a positive energy balance in the face of temporal variation in foraging opportunities. Recent work has shown that spatial heterogeneity in resource phenology can buffer mobile consumers from this constraint by allowing them to track changes in resource availability across space. For example, salmon populations spawn asynchronously across watersheds, causing high-quality foraging opportunities to propagate across the landscape, prolonging the availability of salmon at the regional scale. However, we know little about how individual consumers integrate across phenological variation or the benefits they receive by doing so. Here, we present direct evidence that individual brown bears track spatial variation in salmon phenology. Data from 40 GPS collared brown bears show that bears visited multiple spawning sites in synchrony with the order of spawning phenology. The number of sites used was correlated with the number of days a bear exploited salmon, suggesting the phenological variation in the study area influenced bear access to salmon, a resource which strongly influences bear fitness. Fisheries managers attempting to maximize harvest while maintaining ecosystem function should strive to protect the population diversity that underlies the phenological variation used by wildlife consumers.

  10. Hydrographic influence on the spawning habitat suitability of western Baltic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Hüssy, K.; Hinrichsen, H.-H.; Huwer, B.

    2012-01-01

    are exclusively characterized by ambient water temperatures below the critical survival threshold. Despite the strong influence of water temperature on habitat suitability, the impact of habitat suitability on recruitment was not clearly defined, suggesting that other mechanisms regulate year class strength...... different western Baltic cod spawning grounds for egg survival. Habitat identification was based on environmental threshold levels for egg survival and development and ambient hydrographical conditions at different times during the spawning season. The long-term resolution of environmental conditions...

  11. Snake River Sockeye Salmon Captive Broodstock Program; Hatchery Element, 2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Kline, Paul A.; Willard, Catherine; Baker, Dan J. (Idaho Department of Fish and Game, Boise, ID)

    2003-08-01

    On November 20, 1991, the National Marine Fisheries Service listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. In 1991, the Idaho Department of Fish and Game, the Shoshone-Bannock Tribes, and the National Marine Fisheries Service initiated efforts to conserve and rebuild populations in Idaho. Initial steps to recover sockeye salmon included the establishment of a captive broodstock program at the Idaho Department of Fish and Game Eagle Fish Hatchery. Sockeye salmon broodstock and culture responsibilities are shared with the National Marine Fisheries Service at two locations adjacent to Puget Sound in Washington State. Activities conducted by the Shoshone-Bannock Tribes and the National Marine Fisheries Service are reported under separate cover. Idaho Department of Fish and Game monitoring and evaluation activities of captive broodstock program fish releases (annual report to the Bonneville Power Administration for the research element of the program) are also reported separately. Captive broodstock program activities conducted between January 1, 2001 and December 31, 2001 for the hatchery element of the program are presented in this report. In 2001, 26 anadromous sockeye salmon returned to the Sawtooth Basin. Twenty-three of these adults were captured at adult weirs located on the upper Salmon River and on Redfish Lake Creek. Three of the anadromous sockeye salmon that returned were observed below the Sawtooth Fish Hatchery weir and allowed to migrate upstream volitionally (following the dismantling of the weir on October 12, 2001). Nine anadromous adults were incorporated into the captive broodstock program spawning design in 2001. The remaining adults were released to Redfish Lake for natural spawning. Based on their marks, returning adult sockeye salmon originated from a variety of release options. Two sockeye salmon females from the anadromous group and 152 females from the brood year 1998 captive

  12. Salmon and steelhead in the White Salmon River after the removal of Condit Dam–Planning efforts and recolonization results

    Science.gov (United States)

    Allen, Brady; Engle, Rod O; Zendt, Joseph S; Shrier, Frank C; Wilson, Jeremy T; Connolly, Patrick J.

    2016-01-01

    Condit Dam, at river kilometer 5.3 on the White Salmon River, Washington, was breached in 2011 and completely removed in 2012. This action opened habitat to migratory fish for the first time in 100 years. The White Salmon Working Group was formed to create plans for fish salvage in preparation for fish recolonization and to prescribe the actions necessary to restore anadromous salmonid populations in the White Salmon River after Condit Dam removal. Studies conducted by work group members and others served to inform management decisions. Management options for individual species were considered, including natural recolonization, introduction of a neighboring stock, hatchery supplementation, and monitoring natural recolonization for some time period to assess the need for hatchery supplementation. Monitoring to date indicates that multiple species and stocks of anadromous salmonids are finding and spawning in the now accessible and recovering habitat.

  13. Historical occurrence of coho salmon (Oncorhynchus kisutch) in streams of the Santa Cruz Mountain region of California: response to an Endangered Species Act petition to delist coho salmon south of San Francisco Bay

    Science.gov (United States)

    Brian C. Spence; Walter G. Duffy; John Carlos Garza; Bret Harvey; Susan M. Sogard; Laurie A. Weitkamp; Thomas H. Williams; David A. Boughton

    2011-01-01

    In November 2003, the National Marine Fisheries Service received a petition from Homer T. McCrary to redefine the southern extent of the Central California Coast Coho Salmon Evolutionarily Significant Unit (CCC Coho Salmon ESU) to exclude populations that spawn in coastal watersheds south of the entrance to San Francisco Bay (i.e., the Golden Gate). The petitioner’s...

  14. Differential modulation of resistance biomarkers in skin of juvenile and mature pink salmon, Oncorhynchus gorbuscha by the salmon louse, Lepeophtheirus salmonis.

    Science.gov (United States)

    Braden, Laura M; Barker, Duane E; Koop, Ben F; Jones, Simon R M

    2015-11-01

    Juvenile pink salmon larger than 0.7 g reject the sea louse, Lepeophtheirus salmonis, and are considered resistant to the infection. Robust innate defense responses in the skin contribute to the observed resistance. In contrast adult pink salmon captured at sea or shortly before spawning carry large numbers of the parasite, suggesting inability to control the infection. The purpose of this research is to better understand these apparently contradictory conclusions by comparing a suite of genetic and cellular markers of resistance to L. salmonis in the skin of juvenile and mature pink salmon. The expression of major histocompatibility factor II, C-reactive protein, interleukin-1β, interleukin-8 and cyclooxygenase-2 was down-regulated in mature but not juvenile pink salmon. Similarly, skin at the site of parasite attachment in juvenile salmon was highly populated with MHIIβ(+) and IL-1β(+) cells that were either absent, or at reduced levels at similar sites in mature salmon. In addition, mucocyte density was relatively low in the skin of mature salmon, irrespective of louse infection. In juveniles, the higher mucocyte density decreased following louse attachment. We show that in mature pink salmon, genetic and histological responses in skin are depressed and speculate that salmonid defense against L. salmonis is modulated by maturation. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

  15. Linkages between coastal and open-ocean habitats and dynamics of Japanese stocks of chum salmon and Japanese sardine

    Science.gov (United States)

    Yatsu, Akihiko; Kaeriyama, Masahide

    2005-03-01

    Coastal-ocean-open-ocean migrations, prey-predator relations and long-term population dynamics of chum salmon ( Oncorhynchus keta) and Japanese sardine ( Sardinops melanostictus), associated with large-scale climate and oceanographic conditions, are reviewed. After early marine life in coastal waters in northern Japan, chum salmon of Japanese origin spend their first summer in the Okhotsk Sea, then move to the Western Subarctic Gyre for the first winter at sea. Thereafter, they migrate between summer feeding grounds in the Bering Sea and wintering grounds in the Alaskan Gyre for a period of usually up to four years, and finally return to their natal rivers to spawn. Carrying capacity ( K) for chum salmon at an unfished equilibrium level was estimated from a Ricker spawner-recruitment curve, and the residual carrying capacity ( RCC=(K-abundance)K-1). was positively correlated with body size at age 4, and negatively correlated with age at maturity. Marine survival of Hokkaido chum populations was affected by body size at release, but neither by Aleutian low pressure activity nor sea-surface temperature (SST) around coastal Hokkaido in spring, although there is some correlation between survival rate and coastal SST. Juveniles of the Pacific stock of Japanese sardine become broadly distributed in the Kuroshio Extension (KE) as far east as 180° longitude during spring. Adults disperse as far as the central Pacific and the southern areas of the Okhotsk Sea and Western Subarctic Gyre in years of high abundance. Somatic growth and age at maturation of sardine are density-dependent. We used catch, biomass and residuals of observed recruitment numbers from a Ricker curve (LNRR) as a measure of sardine population dynamics. LNRR was highly correlated with SST of KE in winter, which shifted in 1970 and 1988. Recent biomass and catch remain at extremely low levels due to a combination of adverse environmental conditions and intensive fishing. We suggest that Japanese

  16. Captive Rearing Program for Salmon River Chinook Salmon : Project Progress Report, 2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Venditti, David A.

    2003-10-01

    During 2001, the Idaho Department of Fish and Game continued to develop techniques to rear chinook salmon Oncorhynchus tshawytscha to sexual maturity in captivity and to monitor their reproductive performance under natural conditions. Eyed-eggs were hydraulically collected from redds in the East Fork Salmon River (EFSR; N = 311) and the West Fork Yankee Fork Salmon River (WFYF; N = 272) to establish brood year 2001 culture cohorts. The eyed-eggs were incubated and reared by family group at the Eagle Fish Hatchery (Eagle). Juveniles collected the previous summer were PIT and elastomer tagged and vaccinated against vibrio Vibrio spp. and bacterial kidney disease prior to the majority of them being transferred to the National Marine Fisheries Service, Manchester Marine Experimental Station for saltwater rearing through maturity. Smolt transfers included 210 individuals from the Lemhi River (LEM), 242 from the WFYF, and 178 from the EFSR. Maturing fish transfers from Manchester to Eagle included 62 individuals from the LEM, 72 from the WFYF, and 27 from the EFSR. Additional water chilling capacity was added at Eagle in 2001 to test if spawn timing could be advanced by temperature manipulations, and adults from the LEM and WFYF were divided into chilled ({approx} 9 C) and ambient ({approx} 13.5 C) water temperature groups while at Eagle. Twenty-five mature females from the LEM (11 chilled, 14 ambient) were spawned in captivity with 23 males with the same temperature history in 2001. Water temperature group was not shown to affect the spawn timing of these females, but males did mature earlier. Egg survival to the eyed stage of development averaged 37.9% and did not differ significantly between the two temperature groups. A total of 8,154 eyed-eggs from these crosses were placed in in-stream incubators by personnel from the Shoshone-Bannock Tribe. Mature adults (N = 89) were released into the WFYF to evaluate their reproductive performance. After release, fish

  17. Snake River Sockeye Salmon Captive Broodstock Program; Hatchery Element, 1997 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Kline, Paul A.; Heindel, Jeff A.; Willard, Catherine (Idaho Department of Fish and Game, Boise, ID)

    2003-08-01

    On November 20, 1991, the National Marine Fisheries Service listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. In 1991, the Idaho Department of Fish and Game, the Shoshone-Bannock Tribes, and the National Marine Fisheries Service initiated efforts to conserve and rebuild populations in Idaho. Initial steps to recover sockeye salmon included the establishment of a captive broodstock program at the Idaho Department of Fish and Game Eagle Fish Hatchery. Sockeye salmon broodstock and culture responsibilities are shared with the National Marine Fisheries Service at two locations adjacent to Puget Sound in Washington State. Activities conducted by the Shoshone-Bannock Tribes and the National Marine Fisheries Service are reported under separate cover. Idaho Department of Fish and Game monitoring and evaluation activities of captive broodstock program fish releases (annual report to the Bonneville Power Administration for the research element of the program) are also reported under separate cover. Captive broodstock program activities conducted between January 1, 1997 and December 31, 1997 are presented in this report. One hundred twenty-six female sockeye salmon from one captive broodstock group were spawned at the Eagle Fish Hatchery in 1997. Successful spawn pairings produced approximately 148,781 eyed-eggs with a cumulative mean survival to eyed-egg rate of 57.3%. Approximately 361,600 sockeye salmon were released to Sawtooth basin waters in 1997. Reintroduction strategies included eyed-eggs (brood year 1997), presmolts (brood year 1996), and prespawn adults for volitional spawning (brood year 1994). Release locations included Redfish Lake, Alturas Lake, and Pettit Lake. During this reporting period, four broodstocks and two unique production groups were in culture at the Eagle Fish Hatchery. Two of the four broodstocks were incorporated into the 1997 spawning design, and one broodstock was terminated following

  18. Updraft gasification of salmon processing waste.

    Science.gov (United States)

    Rowland, Sarah; Bower, Cynthia K; Patil, Krushna N; DeWitt, Christina A Mireles

    2009-10-01

    The purpose of this study was to judge the feasibility of gasification for the disposal of waste streams generated through salmon harvesting. Gasification is the process of converting carbonaceous materials into combustible "syngas" in a high temperature (above 700 degrees C), oxygen deficient environment. Syngas can be combusted to generate power, which recycles energy from waste products. At 66% to 79% moisture, raw salmon waste streams are too wet to undergo pyrolysis and combustion. Ground raw or de-oiled salmon whole fish, heads, viscera, or frames were therefore "dried" by mixing with wood pellets to a final moisture content of 20%. Ground whole salmon with moisture reduced to 12% moisture was gasified without a drying agent. Gasification tests were performed in a small-scale, fixed-bed, updraft gasifer. After an initial start-up period, the gasifier was loaded with 1.5 kg of biomass. Temperature was recorded at 6 points in the gasifier. Syngas was collected during the short steady-state period during each gasifier run and analyzed. Percentages of each type of gas in the syngas were used to calculate syngas heating value. High heating value (HHV) ranged from 1.45 to 1.98 MJ/kg. Bomb calorimetry determined maximum heating value for the salmon by-products. Comparing heating values shows the efficiency of gasification. Cold gas efficiencies of 13.6% to 26% were obtained from the various samples gasified. Though research of gasification as a means of salmon waste disposal and energy production is ongoing, it can be concluded that pre-dried salmon or relatively low moisture content mixtures of waste with wood are gasifiable.

  19. Histological assessment of organs in sexually mature and post-spawning steelhead trout and insights into iteroparity

    Science.gov (United States)

    Penney, Zachary L.; Moffitt, Christine M.

    2014-01-01

    Steelhead trout (Oncorhynchus mykiss) are anadromous and iteroparous, but repeat-spawning rates are generally low. Like other anadromous salmonids, steelhead trout fast during freshwater spawning migrations, but little is known about the changes that occur in vital organs and tissues. We hypothesized that fish capable of repeat-spawning would not undergo the same irreversible degeneration and cellular necrosis documented in semelparous salmon. Using Snake River steelhead trout as a model we used histological analysis to assess the cellular architecture in the pyloric stomach, ovary, liver, and spleen in sexually mature and kelt steelhead trout. We observed 38 % of emigrating kelts with food or fecal material in the gastrointestinal tract. Evidence of feeding was more likely in good condition kelts, and feeding was associated with a significant renewal of villi in the pyloric stomach. No vitellogenic oocytes were observed in sections of kelt ovaries, but perinucleolar and early/late stage cortical alveolus oocytes were present suggesting iteroparity was possible. We documented a negative correlation between the quantity of perinucleolar oocytes in ovarian tissues and fork length of kelts suggesting that larger steelhead trout may invest more into a single spawning event. Liver and spleen tissues of both mature and kelt steelhead trout had minimal cellular necroses. Our findings indicate that the physiological processes causing rapid senescence and death in semelparous salmon are not evident in steelhead trout, and recovery begins in fresh water. Future management efforts to increase iteroparity in steelhead trout and Atlantic salmon must consider the physiological processes that influence post-spawning recovery.

  20. Skeletal muscle protease activities in the early growth and development of wild Atlantic salmon (Salmo salar L.).

    Science.gov (United States)

    Lysenko, Liudmila A; Kantserova, Nadezda P; Kaivarainen, Elena I; Krupnova, Marina Yu; Nemova, Nina N

    2017-09-01

    Growth-related dynamics of intracellular protease activities in four year classes of the Atlantic salmon (Salmo salar L. 1758) parr and smolts inhabiting salmon rivers of northwestern Russia (the White Sea basin) were studied. Cathepsin B, cathepsin D, proteasome, and calpain activities in the skeletal muscles of salmon were assessed to investigate their relative contribution to the total protein degradation as well as to young fish growth process. It was confirmed that calpain activity dominates in salmon muscles while proteasome plays a minor role, in contrast to terrestrial vertebrates. Calpain and proteasome activities were maximal at the early post-larval stage (in parrs 0+) and declined with age (parrs 1+ through 2+) dropping to the lowest level in salmon smolts. Annual growth increments and proteolytic activities of calpains and proteasome in the muscles of salmon juveniles changed with age in an orchestrated manner, while lysosomal cathepsin activities increased with age. Comparing protease activities and growth increments in salmon parr and smolts we suggested that the partial suppression of the protein degradation could be a mechanism stimulating efficient growth in smoltifying salmon. Growth and smoltification-related dynamics of protease activities was quite similar in salmon populations from studied spawning rivers, such as Varzuga and Indera; however, some habitat-related differences were observed. Growth increments and protease activities varied in salmon parr 0+ (but not on later ages) inhabiting either main rivers or small tributaries apparently due to habitat difference on the resources for fish growth. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Sex that moves mountains: The influence of spawning fish on river profiles over geologic timescales

    Science.gov (United States)

    Fremier, Alexander K.; Yanites, Brian J.; Yager, Elowyn M.

    2018-03-01

    A key component of resilience is to understand feedbacks among components of biophysical systems, such as physical drivers, ecological responses and the subsequent feedbacks onto physical process. While physically based explanations of biological speciation are common (e.g., mountains separating a species can lead to speciation), less common is the inverse process examined: can a speciation event have significant influence on physical processes and patterns in a landscape? When such processes are considered, such as with 'ecosystem engineers', many studies have focused on the short-term physical and biological effects rather than the long-term impacts. Here, we formalized the physical influence of salmon spawning on stream beds into a model of channel profile evolution by altering the critical shear stress required to move stream bed particles. We then asked if spawning and an adaptive radiation event (similar to the one that occurred in Pacific salmon species) could have an effect on channel erosion processes and stream profiles over geological timescales. We found that spawning can profoundly influence the longitudinal profiles of stream beds and thereby the evolution of entire watersheds. The radiation of five Pacific salmon from a common ancestor, additionally, could also cause significant geomorphic change by altering a wider section of the profile for a given distribution of grain sizes. This modeling study suggests that biological evolution can impact landscape evolution by increasing the sediment transport and erosion efficiency of mountain streams. Moreover, the physical effects of a species on its environment might be a complementary explanation for rapid radiation events in species through the creation of new habitat types. This example provides an illustrative case for thinking about the long- and short-term coupling of biotic and abiotic systems.

  2. Snake River Sockeye Salmon Captive Broodstock Program; Hatchery Element, 1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Dan J,; Heindel, Jeff A.; Kline, Paul A. (Idaho Department of Fish and Game, Boise, ID)

    2005-08-01

    On November 20, 1991, the National Marine Fisheries Service listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. In 1991, the Idaho Department of Fish and Game, the Shoshone-Bannock Tribes, and the National Marine Fisheries Service initiated efforts to conserve and rebuild populations in Idaho. Initial steps to recover sockeye salmon included the establishment of a captive broodstock program at the Idaho Department of Fish and Game Eagle Fish Hatchery. Sockeye salmon broodstock and culture responsibilities are shared with the National Marine Fisheries Service at two locations adjacent to Puget Sound in Washington State. Activities conducted by the Shoshone-Bannock Tribes and the National Marine Fisheries Service are reported under separate cover. Idaho Department of Fish and Game monitoring and evaluation activities of captive broodstock program fish releases are also reported under separate cover. Captive broodstock program activities conducted between January 1, 1999 and December 31, 1999 are presented in this report. In 1999, seven anadromous sockeye salmon returned to the Sawtooth Valley and were captured at the adult weir located on the upper Salmon River. Four anadromous adults were incorporated in the captive broodstock program spawning design for year 1999. The remaining three adults were released to Redfish Lake for natural spawning. All seven adults were adipose and left ventral fin-clipped, indicating hatchery origin. One sockeye salmon female from the anadromous group and 81 females from the captive broodstock group were spawned at the Eagle Fish Hatchery in 1999. Spawn pairings produced approximately 63,147 eyed-eggs with egg survival to eyed-stage of development averaging 38.97%. Eyed-eggs (20,311), presmolts (40,271), smolts (9,718), and adults (21) were planted or released into Sawtooth Valley waters in 1999. Supplementation strategies involved releases to Redfish Lake, Redfish Lake Creek

  3. Environmental variability and chum salmon production at the northwestern Pacific Ocean

    Science.gov (United States)

    Kim, Suam; Kang, Sukyung; Kim, Ju Kyoung; Bang, Minkyoung

    2017-12-01

    Chum salmon, Oncorhynchus keta, are distributed widely in the North Pacific Ocean, and about 76% of chum salmon were caught from Russian, Japanese, and Korean waters of the northwestern Pacific Ocean during the last 20 years. Although it has been speculated that the recent increase in salmon production was aided by not only the enhancement program that targeted chum salmon but also by favorable ocean conditions since the early 1990s, the ecological processes for determining the yield of salmon have not been clearly delineated. To investigate the relationship between yield and the controlling factors for ocean survival of chum salmon, a time-series of climate indices, seawater temperature, and prey availability in the northwestern Pacific including Korean waters were analyzed using some statistical tools. The results of cross-correlation function (CCF) analysis and cumulative sum (CuSum) of anomalies indicated that there were significant environmental changes in the North Pacific during the last century, and each regional stock of chum salmon responded to the Pacific Decadal Oscillation (PDO) differently: for Russian stock, the correlations between PDO index and catch were significantly negative with a time-lag of 0 and 1 years; for Japanese stock, significantly positive with a timelag of 0-2 years; and for Korean stock, positive but no significant correlation. The results of statistical analyses with Korean chum salmon also revealed that a coastal seawater temperature over 14°C and the return rate of spawning adults to the natal river produced a significant negative correlation.

  4. A mathematical model of salmonid spawning habitat

    Science.gov (United States)

    Robert N. Havis; Carlos V. Alonzo; Keith E Woeste; Russell F. Thurow

    1993-01-01

    A simulation model [Salmonid Spawning Analysis Model (SSAM)I was developed as a management tool to evaluate the relative impacts of stream sediment load and water temperature on salmonid egg survival. The model is usefi.il for estimating acceptable sediment loads to spawning habitat that may result from upland development, such as logging and agriculture. Software in...

  5. Captive Rearing Program for Salmon River Chinook Salmon, 2000 Project Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Venditti, David A.

    2002-04-01

    During 2000, the Idaho Department of Fish and Game (IDFG) continued to develop techniques to rear chinook salmon Oncorhynchus tshawytscha to sexual maturity in captivity and to monitor their reproductive performance under natural conditions. Eyed-eggs were collected to establish captive cohorts from three study streams and included 503 eyed-eggs from East Fork Salmon River (EFSR), 250 from the Yankee Fork Salmon River, and 304 from the West Fork Yankee Fork Salmon River (WFYF). After collection, the eyed-eggs were immediately transferred to the Eagle Fish Hatchery, where they were incubated and reared by family group. Juveniles collected the previous summer were PIT and elastomer tagged and vaccinated against vibrio Vibrio spp. and bacterial kidney disease before the majority (approximately 75%) were transferred to the National Marine Fisheries Service, Manchester Marine Experimental Station for saltwater rearing through sexual maturity. Smolt transfers included 158 individuals from the Lemhi River (LEM), 193 from the WFYF, and 372 from the EFSR. Maturing fish transfers from the Manchester facility to the Eagle Fish Hatchery included 77 individuals from the LEM, 45 from the WFYF, and 11 from the EFSR. Two mature females from the WFYF were spawned in captivity with four males in 2000. Only one of the females produced viable eggs (N = 1,266), which were placed in in-stream incubators by personnel from the Shoshone-Bannock Tribe. Mature adults (N = 70) from the Lemhi River were released into Big Springs Creek to evaluate their reproductive performance. After release, fish distributed themselves throughout the study section and displayed a progression of habitat associations and behavior consistent with progressing maturation and the onset of spawning. Fifteen of the 17 suspected redds spawned by captive-reared parents in Big Springs Creek were hydraulically sampled to assess survival to the eyed stage of development. Eyed-eggs were collected from 13 of these, and

  6. Behavioral Ecology of Coral Reef Fishes at Spawning Aggregation Sites

    National Research Council Canada - National Science Library

    Sancho, Gorka

    1998-01-01

    This thesis is an extensive investigation of the behavioral and ecological relationships between spawning reef fishes, their predators, and various environmental parameters at spawning aggregation sites...

  7. Spatial consistency of Chinook salmon redd distribution within and among years in the Cowlitz River, Washington

    Energy Technology Data Exchange (ETDEWEB)

    Klett, Katherine J.; Torgersen, Christian; Henning, Julie; Murray, Christopher J.

    2013-04-28

    We investigated the spawning patterns of Chinook salmon Oncorhynchus tshawytscha on the lower Cowlitz River, Washington (USA) using a unique set of fine- and coarse-scale 35 temporal and spatial data collected during bi-weekly aerial surveys conducted in 1991-2009 (500 m to 28 km resolution) and 2008-2009 (100-500 m resolution). Redd locations were mapped from a helicopter during 2008 and 2009 with a hand-held global positioning system (GPS) synchronized with in-flight audio recordings. We examined spatial patterns of Chinook salmon redd reoccupation among and within years in relation to segment-scale geomorphic features. Chinook salmon spawned in the same sections each year with little variation among years. On a coarse scale, five years (1993, 1998, 2000, 2002, and 2009) were compared for reoccupation. Redd locations were highly correlated among years resulting in a minimum correlation coefficient of 0.90 (adjusted P = 0.002). Comparisons on a fine scale (500 m) between 2008 and 2009 also revealed a high degree of consistency among redd locations (P < 0.001). On a finer temporal scale, we observed that salmon spawned in the same sections during the first and last week (2008: P < 0.02; and 2009: P < 0.001). Redds were clustered in both 2008 and 2009 (P < 0.001). Regression analysis with a generalized linear model at the 500-m scale indicated that river kilometer and channel bifurcation were positively associated with redd density, whereas sinuosity was negatively associated with redd density. Collecting data on specific redd locations with a GPS during aerial surveys was logistically feasible and cost effective and greatly enhanced the spatial precision of Chinook salmon spawning surveys.

  8. Snake River Sockeye Salmon Habitat and Limnological Research; 2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Taki, Doug; Kohler, Andre E. (Shoshone-Bannock Tribes, Fort Hall, ID); Griswold, Robert G. (Biolines, Stanley, ID)

    2004-01-01

    In March 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list the Snake River sockeye salmon (Oncorhynchus nerka) as endangered. As a result of that petition, the Snake River sockeye salmon was officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991, the Snake River Sockeye Salmon Habitat and Limnological Research Program was implemented (Project Number 1991-071-00). This project is part of an interagency effort to prevent the extinction of the Redfish Lake stock of sockeye salmon. The Shoshone-Bannock Tribal goal for this project is two tiered: The immediate goal is to increase the population of Snake River sockeye salmon while preserving the unique genetic characteristics of the Evolutionarily Significant Unit (ESU). The Tribes long term goal is to maintain a viable population that warrants delisting and provides Tribal harvest opportunities. The Bonneville Power Administration (BPA) provides funding for this interagency recovery program through the Northwest Power and Conservation Council Fish and Wildlife Program (NPCCFWP). Collaborators in the recovery effort include the National Oceanic and Atmospheric Administration (NOAA), the Idaho Department of Fish and Game (IDFG), the University of Idaho (UI), and the Shoshone-Bannock Tribes (SBT). This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the 2003 calendar year. Project objectives include: (1) monitor limnological parameters of the Sawtooth Valley lakes to assess lake productivity; (2) reduce the number of mature kokanee spawning in Fishhook Creek; (3) monitor sockeye salmon smolt migration from the captive rearing program release of juveniles into Pettit and Alturas lakes; (4) monitor spawning kokanee escapement and estimate fry recruitment in Fishhook, Alturas Lake, and Stanley Lake creeks; (5) conduct sockeye and kokanee salmon population surveys; (6

  9. Snake River Sockeye Salmon Habitat and Limnological Research : 2005 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Taki, Doug; Kohler, Andre E.; Griswold, Robert G.; Gilliland, Kim

    2006-07-14

    In March 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list Snake River sockeye salmon (Oncorhynchus nerka) as endangered. Snake River sockeye salmon were officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991, the Snake River Sockeye Salmon Habitat and Limnological Research Project was implemented. This project is part of an interagency effort to prevent the extinction of the Redfish Lake stock of Snake River sockeye salmon. The Shoshone-Bannock Tribal goal for this project is two tiered: The immediate goal is to increase the population of Snake River sockeye salmon while preserving the unique genetic characteristics of the Evolutionarily Significant Unit (ESU). The Tribes long term goal is to maintain a viable population that warrants delisting and provides Tribal harvest opportunities. The Bonneville Power Administration (BPA) provides funding for this interagency recovery. Collaborators in the recovery effort include the National Oceanic and Atmospheric Administration (NOAA), the Idaho Department of Fish and Game (IDFG), the University of Idaho (UI), and the Shoshone-Bannock Tribes (SBT). This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the 2005 calendar year. Project tasks include: (1) monitor limnological parameters of the Sawtooth Valley lakes to assess lake productivity; (2) conduct lake fertilization in Pettit and Alturas lakes; (3) reduce the number of mature kokanee spawning in Fishhook and Alturas Lake creeks; (4) monitor and enumerate sockeye salmon smolt migration from Pettit and Alturas lakes; (5) monitor spawning kokanee escapement and estimate fry recruitment in Fishhook, Alturas Lake, and Stanley Lake creeks; (6) conduct sockeye and kokanee salmon population surveys; (7) evaluate potential competition and predation between stocked juvenile sockeye salmon and a variety of fish species in

  10. Repeat surveys of spawning cisco (Coregonus artedi) in western Lake Superior: timing, distribution and composition of spawning stocks

    Science.gov (United States)

    Yule, Daniel L.; Schreiner, Donald R.; Addison, Peter A.; Seider, Michael J.; Evrard, Lori M.; Geving, Steven A.; Quinlan, Henry R.

    2012-01-01

    Acoustic (AC) and midwater trawl (MT) surveys of spawning cisco (Coregonus artedi) in Lake Superior have been combined with commercial yield to estimate exploitation. To time surveys properly, it is important to understand when adults typically arrive at spawning grounds and how numbers change as the spawning season progresses. We conducted repeat autumn surveys during nighttime hours at coastal sites where commercial roe fisheries occur. Spawner densities increased significantly from October to mid-November, but differences measured at sites sampled from mid- to late-November were comparatively small. Spawners occupied the upper 20–30 m of the water column during mid-November before utilizing a wider range of depths by late-November. We compared repeat AC densities to temporal trends of catch-per-unit-effort (CPUE) in suspended commercial gillnets and found good agreement within sites. Because different gillnet mesh sizes were used in each roe fishery. CPUE and AC density were poorly correlated among sites. We recommend that future surveys be conducted between mid- and late-November, and that MT gear be used to measure cisco densities in the uppermost 10 m of the water column where AC estimates may be conservative. Given the short temporal window for assessing spawner density, we believe both AC-MT and gillnet surveys will be needed to ensure that harvest of different stocks is kept at a sustainable level.

  11. Salmon Site Remedial Investigation Report

    International Nuclear Information System (INIS)

    1999-01-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  12. Determination of temporal spawning patterns and hatching time in response to temperature of Atlantic bluefin tuna (Thunnus thynnus in the Western Mediterranean.

    Directory of Open Access Journals (Sweden)

    Ana Gordoa

    Full Text Available This study analysed the temporal pattern of Atlantic bluefin tuna (ABFT spawning in the Balearic spawning ground and examined its reproductive performance after years in captivity. Furthermore, ABFT hatching time at different on-site temperatures was determined for the first time. Spawning surveys were carried out in 4 spawning seasons (2009-2012 aboard tuna transport vessels. Three groups of spawners were monitored: a captive group transported to the spawning region and monitored throughout the four spawning seasons and two wild groups caught in 2009 and 2010 which were transferred to a monitoring transport cage immediately after being caught. Surface plankton samples were collected nightly, beginning immediately after the first purse seine catches were made and concluding after spawning was observed to have ended. All groups displayed the same spawning hours, restricted between 2:00-5:00 a.m. The captive group, as they got older, shifted towards the earliest hour, suggesting an age influence on reproductive time. The onset of spawning varied annually from the end of May to the beginning of June at temperatures around 19 °C-20 °C, ending by the second week of July. The peak of spawning was consistently around the summer solstice, June 15th-30th. The results showed the negative effect of unstable oceanographic conditions in the spawning process which might influence the annual reproductive success of ABFT. The influence of temperature on hatching time was higher than that observed in other tuna species, twice as fast at 26 °C (23 h as at 19.5 °C (49 h. Overall, this study shows the strength of the internal mechanism in ABFT that controls spawning traits. Spawning in ABFT is cyclical and highly synchronised on diel and annual scales. We consider that the timing of spawning is rather influenced by day length and its adaptive significance is discussed.

  13. Determination of temporal spawning patterns and hatching time in response to temperature of Atlantic bluefin tuna (Thunnus thynnus) in the Western Mediterranean.

    Science.gov (United States)

    Gordoa, Ana; Carreras, Gustavo

    2014-01-01

    This study analysed the temporal pattern of Atlantic bluefin tuna (ABFT) spawning in the Balearic spawning ground and examined its reproductive performance after years in captivity. Furthermore, ABFT hatching time at different on-site temperatures was determined for the first time. Spawning surveys were carried out in 4 spawning seasons (2009-2012) aboard tuna transport vessels. Three groups of spawners were monitored: a captive group transported to the spawning region and monitored throughout the four spawning seasons and two wild groups caught in 2009 and 2010 which were transferred to a monitoring transport cage immediately after being caught. Surface plankton samples were collected nightly, beginning immediately after the first purse seine catches were made and concluding after spawning was observed to have ended. All groups displayed the same spawning hours, restricted between 2:00-5:00 a.m. The captive group, as they got older, shifted towards the earliest hour, suggesting an age influence on reproductive time. The onset of spawning varied annually from the end of May to the beginning of June at temperatures around 19 °C-20 °C, ending by the second week of July. The peak of spawning was consistently around the summer solstice, June 15th-30th. The results showed the negative effect of unstable oceanographic conditions in the spawning process which might influence the annual reproductive success of ABFT. The influence of temperature on hatching time was higher than that observed in other tuna species, twice as fast at 26 °C (23 h) as at 19.5 °C (49 h). Overall, this study shows the strength of the internal mechanism in ABFT that controls spawning traits. Spawning in ABFT is cyclical and highly synchronised on diel and annual scales. We consider that the timing of spawning is rather influenced by day length and its adaptive significance is discussed.

  14. Snake River Sockeye Salmon Captive Broodstock Program; Hatchery Element, 2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Willard, Catherine; Baker, Dan J.; Heindel, Jeff A. (Idaho Department of Fish and Game, Boise, ID)

    2003-12-01

    On November 20, 1991, the National Marine Fisheries Service listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. In 1991, the Idaho Department of Fish and Game, the Shoshone-Bannock Tribes, and the National Marine Fisheries Service initiated efforts to conserve and rebuild populations in Idaho. Initial steps to recover sockeye salmon included the establishment of a captive broodstock program at the Idaho Department of Fish and Game Eagle Fish Hatchery. Sockeye salmon broodstock and culture responsibilities are shared with the National Oceanic and Atmospheric Administration at two locations adjacent to Puget Sound in Washington State. Activities conducted by the Shoshone-Bannock Tribes and the National Oceanic and Atmospheric Administration are reported under separate cover. Idaho Department of Fish and Game monitoring and evaluation activities of captive broodstock program fish releases (annual report to the Bonneville Power Administration for the research element of the program) are also reported separately. Captive broodstock program activities conducted between January 1, 2002 and December 31, 2002 for the hatchery element of the program are presented in this report. n 2002, 22 anadromous sockeye salmon returned to the Sawtooth Valley. Fifteen of these adults were captured at adult weirs located on the upper Salmon River and on Redfish Lake Creek. Seven of the anadromous sockeye salmon that returned were observed below the Sawtooth Fish Hatchery weir and allowed to migrate upstream volitionally (following the dismantling of the weir on September 30, 2002). All adult returns were released to Redfish Lake for natural spawning. Based on their marks, returning adult sockeye salmon originated from a variety of release options. Sixty-six females from brood year 1999 and 28 females from brood year 2000 captive broodstock groups were spawned at the Eagle Hatchery in 2002. Spawn pairings produced approximately 65

  15. Results from a sixteen year study on the effects of oiling from the Exxon Valdez on adult pink salmon returns.

    Science.gov (United States)

    Brannon, Ernest L; Maki, Alan W; Moulton, Lawrence L; Parker, Keith R

    2006-08-01

    For sixteen years following the 1989 Exxon Valdez oil spill adult returns of pink salmon in Prince William Sound, Alaska were monitored to assess spill effects on survival. No evidence of spill effects was detected for either intertidal or whole-stream spawning fish. From 1989 through 2004 mean densities for oiled and reference streams tracked each other, illustrating similar responses of oiled and reference stream adult populations to naturally changing oceanographic and climactic conditions. Hatchery fish strayed into the study streams, but similar incursions occurred in oiled and reference streams, and their presence was compensated for to eliminate their influence on determining the success of the returning natural populations. These results, showing no detectable effects of oiling on pink salmon spawning populations, are supported by published field studies on pink salmon incubation success in oiled streams.

  16. Results from a sixteen year study on the effects of oiling from the Exxon Valdez on adult pink salmon returns

    Energy Technology Data Exchange (ETDEWEB)

    Brannon, E.L. [University of Idaho, Moscow, ID (United States). Center for Salmonid and Feshwater Species at Risk; Maki, A.W. [Exxon Mobil Production Company, Anchorage, AK (United States); Moulton, L.L. [MJM Research, Lopez Island, WA (United States); Parker, K.R. [Data Analysis Group, Cloverdale, CA (United States)

    2006-08-15

    For sixteen years following the 1989 Exxon Valdez oil spill adult returns of pink salmon in Prince William Sound, Alaska were monitored to assess spill effects on survival. No evidence of spill effects was detected for either intertidal or whole-stream spawning fish. From 1989 through 2004 mean densities for oiled and reference streams tracked each other, illustrating similar responses of oiled and reference stream adult populations to naturally changing oceanographic and climactic conditions. Hatchery fish strayed into the study streams, but similar incursions occurred in oiled and reference streams, and their presence was compensated for to eliminate their influence on determining the success of the returning natural populations. These results, showing no detectable effects of oiling on pink salmon spawning populations, are supported by published field studies on pink salmon incubation success in oiled streams. (author)

  17. Diverse juvenile life-history behaviours contribute to the spawning stock of an anadromous fish population

    Science.gov (United States)

    Walsworth, Timothy E.; Schindler, Daniel E.; Griffiths, Jennifer R.; Zimmerman, Christian E.

    2015-01-01

    Habitat quality often varies substantially across space and time, producing a shifting mosaic of growth and mortality trade-offs across watersheds. Traditional studies of juvenile habitat use have emphasised the evolution of single optimal strategies that maximise recruitment to adulthood and eventual fitness. However, linking the distribution of individual behaviours that contribute to recruitment at the population level has been elusive, particularly for highly fecund aquatic organisms. We examined juvenile habitat use within a population of sockeye salmon (Oncorhynchus nerka) that spawn in a watershed consisting of two interconnected lakes and a marine lagoon. Otolith microchemical analysis revealed that the productive headwater lake accounted for about half of juvenile growth for those individuals surviving to spawn in a single river in the upper watershed. However, 47% of adults had achieved more than half of their juvenile growth in the downstream less productive lake, and 3% of individuals migrated to the estuarine environment during their first summer and returned to freshwater to overwinter before migrating back to sea. These results describe a diversity of viable habitat-use strategies by juvenile sockeye salmon that may buffer the population against poor conditions in any single rearing environment, reduce density-dependent mortality and have implications for the designation of critical habitat for conservation purposes. A network of accessible alternative habitats providing trade-offs in growth and survival may be important for long-term viability of populations.

  18. Snake River Sockeye Salmon (Oncorhynchus Nerka) Habitat/Limnologic Research : Annual Report 1992.

    Energy Technology Data Exchange (ETDEWEB)

    Spaulding, Scott

    1993-05-01

    This report outlines long-term planning and monitoring activities that occurred in 1991 and 1992 in the Stanley Basin Lakes of the upper Salmon River, Idaho for the purpose of sockeye salmon nerka) recovery. Limnological monitoring and experimental sampling protocol, designed to establish a limnological baseline and to evaluate sockeye salmon production capability of the lakes, are presented. Also presented are recommended passage improvements for current fish passage barriers/impediments on migratory routes to the lakes. We initiated O. nerka population evaluations for Redfish and Alturas lakes; this included population estimates of emerging kokanee fry entering each lake in the spring and adult kokanee spawning surveys in tributary streams during the fall. Gill net evaluations of Alturas, Pettit, and Stanley lakes were done in September, 1992 to assess the relative abundance of fish species among the Stanley Basin lakes. Fish population data will be used to predict sockeye salmon production potential within a lake, as well as a baseline to monitor long-term fish community changes as a result of sockeye salmon recovery activities. Also included is a paper that reviews sockeye salmon enhancement activities in British Columbia and Alaska and recommends strategies for the release of age-0 sockeye salmon that will be produced from the current captive broodstock.

  19. Redfish Lake sockeye salmon captive broodstock rearing and research, 1994. Annual report

    International Nuclear Information System (INIS)

    Flagg, T.A.; McAuley, W.C.; Wastel, M.R.; Frost, D.A.; Mahnken, C.V.W.

    1996-03-01

    The National Marine Fisheries Service (NMFS) Northwest Fisheries Science Center, in cooperation with the Idaho Department of Fish and Game (IDFG) and the Bonneville Power Administration, has established captive broodstocks to aid recovery of Snake River sockeye salmon (Oncorhynchus nerka) listed as endangered under the US Endangered Species Act (ESA). Captive broodstock programs are emerging as an important component of restoration efforts for ESA-listed salmon populations. Captive broodstock programs are a form of artificial propagation. However, they differ from standard hatchery techniques in one important respect: fish are cultured in captivity for the entire life cycle. The high fecundity of Pacific salmon, coupled with their potentially high survival in protective culture, affords an opportunity for captive broodstocks to produce large numbers of juveniles in a single generation for supplementation of natural populations. The captive broodstocks discussed in this report were intended to protect the last known remnants of this stock: sockeye salmon that return to Redfish Lake in the Sawtooth Basin of Idaho at the headwaters of the Salmon River. This report addresses NMFS research from January to December 1994 on the Redfish Lake sockeye salmon captive broodstock program and summarizes results since the beginning of the study in 1991. Spawn from NMFS Redfish Lake sockeye salmon captive broodstocks is being returned to Idaho to aid recovery efforts for the species

  20. Redfish Lake Sockeye Salmon Captive Broodstock Rearing and Research, 1994 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Flagg, Thomas A.

    1996-03-01

    The National Marine Fisheries Service (NMFS) Northwest Fisheries Science Center, in cooperation with the Idaho Department of Fish and Game (IDFG) and the Bonneville Power Administration, has established captive broodstocks to aid recovery of Snake River sockeye salmon (Oncorhynchus nerka) listed as endangered under the US Endangered Species Act (ESA). Captive broodstock programs are emerging as an important component of restoration efforts for ESA-listed salmon populations. Captive broodstock programs are a form of artificial propagation. However, they differ from standard hatchery techniques in one important respect: fish are cultured in captivity for the entire life cycle. The high fecundity of Pacific salmon, coupled with their potentially high survival in protective culture, affords an opportunity for captive broodstocks to produce large numbers of juveniles in a single generation for supplementation of natural populations. The captive broodstocks discussed in this report were intended to protect the last known remnants of this stock: sockeye salmon that return to Redfish Lake in the Sawtooth Basin of Idaho at the headwaters of the Salmon River. This report addresses NMFS research from January to December 1994 on the Redfish Lake sockeye salmon captive broodstock program and summarizes results since the beginning of the study in 1991. Spawn from NMFS Redfish Lake sockeye salmon captive broodstocks is being returned to Idaho to aid recovery efforts for the species.

  1. Quantifying overlap between the Deepwater Horizon oil spill and predicted bluefin tuna spawning habitat in the Gulf of Mexico

    Science.gov (United States)

    Hazen, Elliott L.; Carlisle, Aaron B.; Wilson, Steven G.; Ganong, James E.; Castleton, Michael R.; Schallert, Robert J.; Stokesbury, Michael J. W.; Bograd, Steven J.; Block, Barbara A.

    2016-09-01

    Atlantic bluefin tuna (Thunnus thynnus) are distributed throughout the North Atlantic and are both economically valuable and heavily exploited. The fishery is currently managed as two spawning populations, with the GOM population being severely depleted for over 20 years. In April-August of 2010, the Deepwater Horizon oil spill released approximately 4 million barrels of oil into the GOM, with severe ecosystem and economic impacts. Acute oil exposure results in mortality of bluefin eggs and larvae, while chronic effects on spawning adults are less well understood. Here we used 16 years of electronic tagging data for 66 bluefin tuna to identify spawning events, to quantify habitat preferences, and to predict habitat use and oil exposure within Gulf of Mexico spawning grounds. More than 54,000 km2 (5%) of predicted spawning habitat within the US EEZ was oiled during the week of peak oil dispersal, with potentially lethal effects on eggs and larvae. Although the oil spill overlapped with a relatively small portion of predicted spawning habitat, the cumulative impact from oil, ocean warming and bycatch mortality on GOM spawning grounds may result in significant effects for a population that shows little evidence of rebuilding.

  2. Grande Ronde Basin Chinook Salmon Captive Brood and Conventional Supplementation Programs, 2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Carmichael, Richard W. (Oregon Department of Fish and Wildlife, La Grande, OR)

    2003-03-01

    Endangered Species Permit Number 1011 (formerly Permit No. 973) authorizes ODFW to take listed spring chinook salmon juveniles from Catherine Creek (CC), Lostine River (LR) and Grande Ronde River (GR) for research and enhancement purposes. Modification 2 of this permit authorizes ODFW to take adults for spawning and the production and release of smolts for the Captive and Conventional broodstock programs. This report satisfies the requirement that an annual report be submitted. Herein we report on activities conducted and provide cursory data analyses for the Grande Ronde spring chinook salmon Captive and Conventional broodstock projects from 1 January-31 December 2001.

  3. Grande Ronde Basin Chinook Salmon Captive Brood and Conventional Supplementation Program, 2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Carmichael, Richard W. (Oregon Department of Fish and Wildlife, La Grande, OR)

    2003-03-01

    Endangered Species Permit Number 1011 (formerly Permit No. 973) authorizes ODFW to take listed spring chinook salmon juveniles from Catherine Creek (CC), Lostine River (LR) and Grande Ronde River (GR) for research and enhancement purposes. Modification 2 of this permit authorizes ODFW to take adults for spawning and the production and release of smolts for the Captive and Conventional broodstock programs. This report satisfies the requirement that an annual report be submitted. Herein we report on activities conducted and provide cursory data analyses for the Grande Ronde spring chinook salmon Captive and Conventional broodstock projects from 1 January-31 December 2000.

  4. Unlocking the secrets of Lake Clark sockeye salmon

    Science.gov (United States)

    Woody, Carol Ann

    2003-01-01

    Sockeye salmon are a cornerstone species in many Alaska watersheds. Each summer, adults lay eggs in rocky nests called “redds,” and they die soon after. In spring, their fry emerge from gravels and then rear in a nearby freshwater lake for one year or more before migrating as smolt to the sea. During this smolt phase, an olfactory map of their route is imprinted on their memories. Sockeye salmon spend one to four years in the ocean feeding and growing. Then, some innate cue sends them back in a mass migration to their natal lake systems, which they find using the olfactory map made years before. They complete their life cycle by spawning, then dying in habitats of their birth.

  5. Low level chronic irradiation of salmon. Annual progress report

    International Nuclear Information System (INIS)

    Hershberger, W.K.; Donaldson, L.R.; Bonham, K.; Brannon, E.L.

    1975-01-01

    A question of primary importance in the use of nuclear energy is what effect the effluent from a reactor will have on the aquatic life in the water used for cooling. Of particular concern in the Pacific Northwest are the effects of chronic irradiation on salmon that use the rivers for spawning and nursery area. The present program was designed in the early days of the atomic era to address this concern, and to provide some insight into the long-term consequences of exposure of fish to chronic, low levels of irradiation. The experimental techniques are described and data are summarized on irradiation effects on the entire life cycle of the chinook salmon. Also, long-term effects transmitted to future generations were assessed in F 1 offspring of irradiated parents

  6. Efficacy and toxicity of iodine disinfection of Atlantic salmon eggs

    Science.gov (United States)

    Chalupnicki, M.A.; Ketola, H.G.; Starliper, C.E.; Gallagher, D.

    2011-01-01

    Recent interest in the restoration of Atlantic salmon Salmo salar in the Great Lakes has given rise to new culture techniques and management programs designed to reduce pathogen transmission while stabilizing and enhancing wild populations. We examined the toxicity of iodine to Atlantic salmon eggs and its effectiveness as a disinfectant against bacteria on egg surfaces. We spawned and fertilized eight gravid Atlantic salmon from Cayuga Lake, New York, and exposed their eggs to 10 concentrations of iodine (5, 10, 50, 75, 100, 500, 750, 1,000, 5,000, and 7,500 mg/L) for 30 min during water hardening. An additional subsample of unfertilized eggs was also exposed to some of the same concentrations of iodine (5, 10, 50, 75, and 100 mg/L) to determine the efficiency of disinfection. Viable eggs were only obtained from four females. Survival of eggs to the eyed stage and hatch tended to be reduced at iodine concentrations of 50 and 75 mg/L and was significantly reduced at concentrations of 100 mg/L iodine or more. We calculated the concentrations of iodine that killed 50% of the Atlantic salmon eggs at eye-up and hatch to be 175 and 85 mg/L, respectively. Aeromonas veronii, A. schubertii, A. hydrophila, A. caviae, Plesiomonas shiggeloides, and Citrobacter spp. were the predominant bacteria present on the surface of green eggs and were significantly reduced by an iodine immersion. The use of iodine as a disinfectant on Atlantic salmon eggs was effective at low concentrations (50–75 mg/L), for which toxicity to Atlantic salmon was minimal.

  7. Captive Rearing Program for Salmon River Chinook Salmon, 2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Venditti, David; Willard, Catherine; James, Chris

    2003-11-01

    During 2002, the Idaho Department of Fish and Game continued to develop techniques to rear Chinook salmon Oncorhynchus tshawytscha to sexual maturity in captivity and to monitor their reproductive performance under natural conditions. Eyed-eggs were hydraulically collected from redds in the East Fork Salmon River (EFSR; N = 328) and the West Fork Yankee Fork Salmon River (WFYF; N = 308) to establish brood year 2002 culture cohorts. The eyed-eggs were incubated and reared at the Eagle Fish Hatchery, Eagle, Idaho (Eagle). Juveniles collected in 2000 were PIT and elastomer tagged and vaccinated against vibrio Vibrio spp. and bacterial kidney disease prior to being transferred to the NOAA Fisheries, Manchester Marine Experimental Station, Manchester, Washington (Manchester) for saltwater rearing through maturity. Smolt transfers included 203 individuals from the WFYF and 379 from the EFSR. Maturing fish transfers from Manchester to Eagle included 107 individuals from the LEM, 167 from the WFYF, and 82 from the EFSR. This was the second year maturing adults were held on chilled water at Eagle to test if water temperature manipulations could advance spawn timing. Adults from the LEM and WFYF were divided into chilled ({approx} 9 C) and ambient ({approx} 13.5 C) temperature groups while at Eagle. Forty-seven mature females from the LEM (19 chilled, 16 ambient, and 12 ambient not included in the temperature study) were spawned at Eagle with 42 males in 2002. Water temperature group was not shown to affect the spawn timing of these females, but males did mature earlier. Egg survival to the eyed stage averaged 66.5% and did not differ significantly between the temperature groups. Personnel from the Shoshone-Bannock Tribe placed a total of 47,977 eyed-eggs from these crosses in in-stream incubators. Mature adults (N = 215 including 56 precocial males) were released into the WFYF to evaluate their reproductive performance. After release, fish distributed themselves throughout

  8. Blood types in Pacific salmon

    Science.gov (United States)

    Ridgway, G.L.; Klontz, G.W.

    1961-01-01

    Intraspecific differences in erythrocyte antigens (blood types) were shown to occur in four species of Pacific salmon, the sockeye or red salmon (Oncorhynchus nerka), the chinook or king salmon (0. tshawytscha), the chum salmon (O. keta), and the pink salmon (O. gorbuscha). Antisalmon-erythrocyte sera prepared in rabbits and chickens were used after absorption of species-specific antibodies. Some of these blood types were shown to differ in their frequency of occurrence between different geographic races. In addition, isoimmunizations were conducted on one race of sockeye salmon. Antisera of seven different specificities were prepared and at least eight different patterns of antigenic composition were displayed by the cells tested.

  9. Redfish Lake Sockeye Salmon Captive Broodstock Rearing and Research, 1995-2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Flagg, Thomas A.

    2001-01-01

    The National Marine Fisheries Service (NMFS) Northwest Fisheries Science Center, in cooperation with the Idaho Department of Fish and Game and the Bonneville Power Administration, has established captive broodstocks to aid recovery of Snake River sockeye salmon (Oncorhynchus nerka) listed as endangered under the US Endangered Species Act (ESA). Captive broodstock programs are a form of artificial propagation and are emerging as an important component of restoration efforts for ESA-listed salmon populations. However, they differ from standard hatchery techniques in one important respect: fish are cultured in captivity for the entire life cycle. The high fecundity of Pacific salmon, coupled with their potentially high survival in protective culture, affords an opportunity for captive broodstocks to produce large numbers of juveniles in a single generation for supplementation of natural populations. The captive broodstocks discussed in this report were intended to protect the last known remnants of this stock: sockeye salmon that return to Redfish Lake in the Sawtooth Basin of Idaho at the headwaters of the Salmon River. This report addresses NMFS research from January 1995 to August 2000 on the Redfish Lake sockeye salmon captive broodstock program and summarizes results since the beginning of the study in 1991. Since initiating captive brood culture in 1991, NMFS has returned 742,000 eyed eggs, 181 pre-spawning adults, and over 90,000 smolts to Idaho for recovery efforts. The first adult returns to the Stanley Basin from the captive brood program began with 7 in 1999, and increased to about 250 in 2000. NMFS currently has broodstock in culture from year classes 1996, 1997, 1998, and 1999 in both the captive broodstock program, and an adult release program. Spawn from NMFS Redfish Lake sockeye salmon captive broodstocks is being returned to Idaho to aid recovery efforts for the species.

  10. Atlantic Salmon Smolt Monitoring

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Annual data are collected as part of smolt trapping operations using fish trapping methods. Traps collect emigrating salmon smolts to identify cohort...

  11. Reintroduction of Lower Columbia River Chum Salmon into Duncan Creek, 2007 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hillson, Todd D. [Washington Department of Fish and Wildlife

    2009-06-12

    The National Marine Fisheries Service (NMFS) listed Lower Columbia River (LCR) chum salmon as threatened under the Endangered Species Act (ESA) in March, 1999 (64 FR 14508, March 25, 1999). The listing was in response to the reduction in abundance from historical levels of more than one-half million returning adults to fewer than 10,000 present-day spawners. Harvest, habitat degradation, changes in flow regimes, riverbed movement and heavy siltation have been largely responsible for this decline. The timing of seasonal changes in river flow and water temperatures is perhaps the most critical factor in structuring the freshwater life history of this species. This is especially true of the population located directly below Bonneville Dam, where hydropower operations can block access to spawning sites, dewater redds, strand fry, cause scour or fill of redds and increase sedimentation of spawning gravels. Prior to 1997, only two chum salmon populations were recognized as genetically distinct in the Columbia River, although spawning had been documented in many Lower Columbia River tributaries. The first population was in the Grays River (RKm 34), a tributary of the Columbia River, and the second was a group of spawners utilizing the mainstem Columbia River just below Bonneville Dam (RKm 235) adjacent to Ives Island and in Hardy and Hamilton creeks. Using additional DNA samples, Small et al. (2006) grouped chum salmon spawning in the mainstem Columbia River and the Washington State tributaries into three groups: the Coastal, the Cascade and the Gorge. The Coastal group comprises those spawning in the Grays River, Skamokawa Creek and the broodstock used at the Sea Resources facility on the Chinook River. The Cascade group comprises those spawning in the Cowlitz (both summer and fall stocks), Kalama, Lewis, and East Fork Lewis rivers, with most supporting unique populations. The Gorge group comprises those spawning in the mainstem Columbia River from the I-205 Bridge up to

  12. Genetic changes from artificial propagation of Pacific salmon affect the productivity and viability of supplemented populations

    Science.gov (United States)

    Reisenbichler, R.R.; Rubin, S.P.

    1999-01-01

    Although several studies have shown genetic differences between hatchery and wild anadromous Pacific salmon (Oncorhynchus spp.), none has provided compelling evidence that artificial propagation poses a genetic threat to conservation of naturally spawning populations. When the published studies and three studies in progress are considered collectively, however, they provide strong evidence that the fitness for natural spawning and rearing can be rapidly and substantially reduced by artificial propagation. This issue takes on great importance in the Pacific Northwest where supplementation of wild salmon populations with hatchery fish has been identified as an important tool for restoring these populations. Recognition of negative aspects may lead to restricted use of supplementation, and better conservation, better evaluation, and greater benefits when supplementation is used.

  13. Snake River Sockeye Salmon Captive Broodstock; Research Element, 1993 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, Keith A.

    1995-12-01

    In 1991, the National Marine Fisheries Service listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. Initial steps to recover the species include the establishment of captive broodstocks at the Eagle Fish Hatchery in Eagle, Idaho. Research and recovery activities for sockeye conducted by the Idaho Department of Fish and Game during the period of April 1993 to April 1994 are covered by this report. Eight anadromous adults (two female and six male) returned to the Redfish Lake Creek trap this year and were spawned at the Sawtooth Hatchery near Stanley, Idaho. Fecundity was 3160 for each female. The mean fertilization rate was 52% for female {open_quotes}A{close_quotes} and 65% for female {open_quotes}B.{close_quotes} Captive broodstock also spawned as well as residual sockeye captured in a Merwin trap in Redfish Lake. Spawning data from 72 fish spawned during this period is included in this report. Captive broodstock also matured later than normal (winter and spring 1994). Fish were spawned and samples were taken to investigate reasons for poor fertilization rates. Twenty-four out migrants of 1991 were selected for return to Redfish Lake for volitional spawning. Releases were made in August of 1993. All fish were implanted with sonic tags and tracking of this group began soon after the release to identify spawning-related activities. A research project is being conducted on captive broodstock diets. The project will investigate the effect of diet modification on spawn timing, gamete quality, and fertilization rates. A second project used ultrasound to examine fish for sexual maturity. The goal was to obtain a group a fish to be released f or volitional spawning. A total of 44 fish were found to be mature. The performance of all captive groups held at Eagle are included in this report.

  14. Impacts of the Columbia River hydroelectric system on main-stem habitats of fall chinook salmon

    Science.gov (United States)

    Dauble, D.D.; Hanrahan, T.P.; Geist, D.R.; Parsley, M.J.

    2003-01-01

    Salmonid habitats in main-stem reaches of the Columbia and Snake rivers have changed dramatically during the past 60 years because of hydroelectric development and operation. Only about 13% and 58% of riverine habitats in the Columbia and Snake rivers, respectively, remain. Most riverine habitat is found in the upper Snake River; however, it is upstream of Hells Canyon Dam and not accessible to anadromous salmonids. We determined that approximately 661 and 805 km of the Columbia and Snake rivers, respectively, were once used by fall chinook salmon Oncorhynchus tshawytscha for spawning. Fall chinook salmon currently use only about 85 km of the main-stem Columbia River and 163 km of the main-stem Snake River for spawning. We used a geomorphic model to identify three river reaches downstream of present migration barriers with high potential for restoration of riverine processes: the Columbia River upstream of John Day Dam, the Columbia-Snake-Yakima River confluence, and the lower Snake River upstream of Little Goose Dam. Our analysis substantiated the assertion that historic spawning areas for fall chinook salmon occurred primarily within wide alluvial floodplains, which were once common in the mainstem Columbia and Snake rivers. These areas possessed more unconsolidated sediment and more bars and islands and had lower water surface slopes than did less extensively used areas. Because flows in the main stem are now highly regulated, the predevelopment alluvial river ecosystem is not expected to be restored simply by operational modification of one or more dams. Establishing more normative flow regimes - specifically, sustained peak flows for scouring - is essential to restoring the functional characteristics of existing, altered habitats. Restoring production of fall chinook salmon to any of these reaches also requires that population genetics and viability of potential seed populations (i.e., from tributaries, tailrace spawning areas, and hatcheries) be considered.

  15. Three decades of farmed escapees in the wild: a spatio-temporal analysis of Atlantic salmon population genetic structure throughout Norway.

    Directory of Open Access Journals (Sweden)

    Kevin A Glover

    Full Text Available Each year, hundreds of thousands of domesticated farmed Atlantic salmon escape into the wild. In Norway, which is the world's largest commercial producer, many native Atlantic salmon populations have experienced large numbers of escapees on the spawning grounds for the past 15-30 years. In order to study the potential genetic impact, we conducted a spatio-temporal analysis of 3049 fish from 21 populations throughout Norway, sampled in the period 1970-2010. Based upon the analysis of 22 microsatellites, individual admixture, F(ST and increased allelic richness revealed temporal genetic changes in six of the populations. These changes were highly significant in four of them. For example, 76% and 100% of the fish comprising the contemporary samples for the rivers Vosso and Opo were excluded from their respective historical samples at P=0.001. Based upon several genetic parameters, including simulations, genetic drift was excluded as the primary cause of the observed genetic changes. In the remaining 15 populations, some of which had also been exposed to high numbers of escapees, clear genetic changes were not detected. Significant population genetic structuring was observed among the 21 populations in the historical (global F(ST =0.038 and contemporary data sets (global F(ST =0.030, although significantly reduced with time (P=0.008. This reduction was especially distinct when looking at the six populations displaying temporal changes (global F(ST dropped from 0.058 to 0.039, P=0.006. We draw two main conclusions: 1. The majority of the historical population genetic structure throughout Norway still appears to be retained, suggesting a low to modest overall success of farmed escapees in the wild; 2. Genetic introgression of farmed escapees in native salmon populations has been strongly population-dependent, and it appears to be linked with the density of the native population.

  16. Metabolic effects of dinoseb, diazinon and esfenvalerate in eyed eggs and alevins of Chinook salmon (Oncorhynchus tshawytscha) determined by 1H NMR metabolomics

    International Nuclear Information System (INIS)

    Viant, Mark R.; Pincetich, Christopher A.; Tjeerdema, Ronald S.

    2006-01-01

    Pesticide pulses in the Sacramento River, California, originate from storm-water discharges and non-point source aquatic pollution that can last from a few days to weeks. The Sacramento River and its tributaries have historically supported the majority of California's Chinook salmon (Oncorhynchus tshawytscha) spawning grounds. Three pesticides currently used in the Sacramento Valley - dinoseb, diazinon, and esfenvalerate - were chosen to model the exposure of salmon embryos to storm-water discharges. Static-renewal (96 h) exposures to eyed eggs and alevins resulted in both toxicity and significant changes in metabolism assessed in whole-embryo extracts by 1 H nuclear magnetic resonance (NMR) spectroscopy based metabolomics and HPLC with UV detection (HPLC-UV). The 96-h LC 5 values of eyed eggs and alevins exposed to dinoseb were 335 and 70.6 ppb, respectively, and the corresponding values for diazinon were 545 and 29.5 ppm for eyed eggs and alevins, respectively. The 96-h LC 5 of eyed eggs exposed to esfenvalerate could not be determined due to lack of mortality at the highest exposure concentration, but in alevins was 16.7 ppb. All esfenvalerate exposed alevins developed some degree of lordosis or myoskeletal abnormality and did not respond to stimulus or exhibit normal swimming behavior. ATP concentrations measured by HPLC-UV decreased significantly in eyed eggs due to 250 ppb dinoseb and 10 and 100 ppb esfenvalerate (p 1 H NMR metabolite fingerprints of eyed egg and alevin extracts revealed both dose-dependent and mechanism of action-specific metabolic effects induced by the pesticides. Furthermore, NMR based metabolomics proved to be more sensitive than HPLC-UV in identifying significant changes in sublethal metabolism of pesticide exposed alevins. In conclusion, we have demonstrated several benefits of a metabolomics approach for chemical risk assessment, when used in conjunction with a fish embryo assay, and have identified significant metabolic perturbations

  17. Identifying salmon lice transmission characteristics between Faroese salmon farms

    DEFF Research Database (Denmark)

    Kragesteen, Trondur J.; Simonsen, Knud; Visser, AW

    2018-01-01

    Sea lice infestations are an increasing challenge in the ever-growing salmon aquaculture sector and cause large economic losses. The high salmon production in a small area creates a perfect habitat for parasites. Knowledge of how salmon lice planktonic larvae disperse and spread the infection bet...

  18. Salmon lice – impact on wild salmonids and salmon aquaculture

    Science.gov (United States)

    Torrissen, O; Jones, S; Asche, F; Guttormsen, A; Skilbrei, O T; Nilsen, F; Horsberg, T E; Jackson, D

    2013-01-01

    Salmon lice, Lepeophtheirus salmonis, are naturally occurring parasites of salmon in sea water. Intensive salmon farming provides better conditions for parasite growth and transmission compared with natural conditions, creating problems for both the salmon farming industry and, under certain conditions, wild salmonids. Salmon lice originating from farms negatively impact wild stocks of salmonids, although the extent of the impact is a matter of debate. Estimates from Ireland and Norway indicate an odds ratio of 1.1:1-1.2:1 for sea lice treated Atlantic salmon smolt to survive sea migration compared to untreated smolts. This is considered to have a moderate population regulatory effect. The development of resistance against drugs most commonly used to treat salmon lice is a serious concern for both wild and farmed fish. Several large initiatives have been taken to encourage the development of new strategies, such as vaccines and novel drugs, for the treatment or removal of salmon lice from farmed fish. The newly sequenced salmon louse genome will be an important tool in this work. The use of cleaner fish has emerged as a robust method for controlling salmon lice, and aquaculture production of wrasse is important towards this aim. Salmon lice have large economic consequences for the salmon industry, both as direct costs for the prevention and treatment, but also indirectly through negative public opinion. PMID:23311858

  19. Pacific Coastal Salmon Recovery Fund

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Congress established the Pacific Coastal Salmon Recovery Fund (PCSRF) to monitor the restoration and conservation of Pacific salmon and steelhead populations and...

  20. Genetic differentiation of sockeye salmon subpopulations from a geologically young Alaskan lake system

    Science.gov (United States)

    Burger, C.V.; Spearman, William J.; Cronin, M.A.

    1997-01-01

    The Tustumena lake drainage in southcentral Alaska is glacially turbid and geologically young (salmon Oncorhynchus nerka at Tustumena Lake, based on the distribution and timing of spawners. The subpopulations included early-run salmon that spawned in six clearwater tributaries of the lake (mid August), lake shoreline spawners (late August), and late-run fish that spawned in the lake's outlet, the Kasilof River (late September). Our objective was to determine the degree of genetic differentiation among these subpopulations based on restriction enzyme analyses of the cytochrome b gene of mitochondrial DNA and analyses of four polymorphic allozyme loci. Mitochondrial DNA haplotype frequencies for outlet-spawning sockeye salmon differed significantly from those of all other subpopulations. The most common (36%) haplotype in the outlet subpopulation did not occur elsewhere, thus suggesting little or no gene flow between outlet spawners and other spatially close subpopulations at Tustumena Lake. Allele frequencies at two allozyme loci also indicated a degree of differentiation of the outlet subpopulation from the shoreline and tributary subpopulations. Allele frequencies for three tributary subpopulations were temporally stable over approximately 20 years (based on a comparison to previously published results) despite initiation of a hatchery program in two of the tributaries during the intervening period. Collectively, our results are consistent with the hypothesis that significant genetic differentiation has occurred within the Tustumena Lake drainage since deglaciation approximately 2,000 years ago.

  1. Assessing summer and fall chinook salmon restoration in the Upper Clearwater River and principal tributaries. Annual report 1994

    International Nuclear Information System (INIS)

    Arnsberg, B.D.; Statler, D.P.

    1995-08-01

    This is the first annual report of a five year study to assess summer and fall chinook salmon restoration potential in the upper Clearwater River and principal tributaries, Salmon, Grande Ronde, and Imnaha Rivers. During 1994, the authors focused primarily on assessing water temperatures and spawning habitat in the upper Clearwater River and principal tributaries. Water temperature analysis indicated a colder temperature regime in the upper Clearwater River above the North Fork Clearwater River confluence during the winter as compared to the lower Clearwater. This was due to warm water releases from Dworshak Reservoir on the North Fork moderating temperatures in the lower Clearwater River. Thermal temperature unit analysis and available literature suggest a 75% survival threshold level may be anticipated for chinook salmon egg incubation if spawning would occur by November 1 in the upper Clearwater River. Warm water upwelling in historic summer and fall chinook spawning areas may result in increased incubation survivals and will be tested in the future. The authors observed a total of 37 fall chinook salmon redds in the Clearwater River subbasin. They observed 30 redds in the mainstem Clearwater below the North Fork Clearwater River confluence and seven redds in the North Fork Clearwater River. No redds were observed in the South Fork Clearwater, Middle Fork Clearwater, or Selway Rivers. They observed one fall chinook salmon redd in the Salmon River. They recovered 10 fall chinook salmon carcasses in the Clearwater River to obtain biological measurements and to document hatchery contribution to spawning. Unseasonably high and cold Dworshak Dam releases coinciding with early juvenile fall chinook salmon rearing in the lower Clearwater River may be influencing selective life history traits including growth, smolt development, outmigration timing, behavior, and could be directly affecting survival. During July 1994, discharges from Dworshak Dam increased from a

  2. Size selection from fishways and potential evolutionary responses in a threatened Atlantic salmon population

    Science.gov (United States)

    Maynard, George A.; Kinnison, M.T.; Zydlewski, Joseph D.

    2017-01-01

    The evolutionary effects of harvest on wild fish populations have been documented around the world; however, sublethal selective pressures can also cause evolutionary changes in phenotypes. For migratory fishes, passage facilities may represent instances of nonlethal selective pressure. Our analysis of 6 years of passage data suggests that certain fish passage facilities on the Penobscot River have been exerting selective pressure against large-bodied, anadromous Atlantic salmon (Salmo salar). At the second and third dams in the river, a 91-cm salmon was 21%–27% and 12%–16% less likely to pass than a 45-cm salmon, respectively. Fish size positively influences egg survival and number and is a heritable trait. Therefore, in a wild-reproducing population, exclusion of large fish from spawning areas may have population-level impacts. In the Penobscot River, most returning adults derive from a hatchery program that collects its broodstock after passing the first dam in the river. Analysis of fork lengths of salmon returning to the Penobscot River from 1978 to 2012 provided mixed support for evolution of size at maturity in different age classes in a pattern that may be expected from interactions with conservation hatchery operations. Additionally, slow-maturing and iteroparous individuals that represent the largest salmon size classes were essentially lost from the population during that time, and Penobscot River fish have shorter fork lengths at maturity than Atlantic salmon in undammed systems.

  3. Reconstruction of Pacific salmon abundance from riparian tree-ring growth.

    Science.gov (United States)

    Drake, D C; Naiman, Robert J

    2007-07-01

    We use relationships between modern Pacific salmon (Oncorhynchus spp.) escapement (migrating adults counted at weirs or dams) and riparian tree-ring growth to reconstruct the abundance of stream-spawning salmon over 150-350 years. After examining nine sites, we produced reconstructions for five mid-order rivers and four salmon species over a large geographic range in the Pacific Northwest: chinook (O. tschwatcha) in the Umpqua River, Oregon, USA; sockeye (O. nerka) in Drinkwater Creek, British Columbia, Canada; pink (O. gorbuscha) in Sashin Creek, southeastern Alaska, USA; chum (O. keta) in Disappearance Creek, southeastern Alaska, USA; and pink and chum in the Kadashan River, southeastern Alaska, USA. We first derived stand-level, non-climatic growth chronologies from riparian trees using standard dendroecology methods and differencing. When the chronologies were compared to 18-55 years of adult salmon escapement we detected positive, significant correlations at five of the nine sites. Regression models relating escapement to tree-ring growth at the five sites were applied to the differenced chronologies to reconstruct salmon abundance. Each reconstruction contains unique patterns characteristic of the site and salmon species. Reconstructions were validated by comparison to local histories (e.g., construction of dams and salmon canneries) and regional fisheries data such as salmon landings and aerial surveys and the Pacific Decadal Oscillation climate index. The reconstructions capture lower-frequency cycles better than extremes and are most useful for determination and comparison of relative abundance, cycles, and the effects of interventions. Reconstructions show lower population cycle maxima in both Umpqua River chinook and Sashin Creek pink salmon in recent decades. The Drinkwater Creek reconstruction suggests that sockeye abundance since the mid-1990s has been 15-25% higher than at any time since 1850, while no long-term deviations from natural cycles are

  4. Patterns of color phase indicate spawn timing at a Nassau grouper Epinephelus striatus spawning aggregation

    Directory of Open Access Journals (Sweden)

    Stephanie K ARCHER, Scott A HEPPELL, Brice X SEMMENS,Christy V PATTENGILL-SEMMENS, Phillippe G BUSH, Croy M MCCOY,Bradley C JOHNSON

    2012-02-01

    Full Text Available Nassau grouper Epinephelus striatus are a large bodied, top level predator that is ecologically important throughout the Caribbean. Although typically solitary, Nassau grouper form large annual spawning aggregations at predictable times in specific locations. In 2003, The Cayman Islands Marine Conservation Board established protection for a newly rediscovered Nassau grouper spawning aggregation on Little Cayman, British West Indies. The large size of this aggregation provides a unique opportunity to study the behavior of Nassau grouper on a relatively intact spawning aggregation. During non-spawning periods Nassau grouper display a reddish-brown-and-white barred coloration. However, while aggregating they exhibit three additional color phases: “bicolor”, “dark”, and “white belly”. We video sampled the population on multiple days leading up to spawning across five spawning years. Divers focused a laser caliper equipped video camera on individual fish at the aggregation. We later analyzed the video to determine the length of the fish and record the color phase. Our observations show that the relative proportion of fish in the bicolor color phase increases significantly on the day leading up to the primary night of spawning. The increase in the proportion of the bicolor color phase from 0.05 early in the aggregation to 0.40 on the day of spawning suggests that this color phase conveys that a fish is behaviorally and physiologically prepared to spawn. Additionally, 82.7% of fish exhibiting dark or white belly coloration early in the aggregation period suggests that these color phases are not only shown by female fish as was previously posited [Current Zoology 58 (1: 73–83, 2012].

  5. Grande Ronde Basin Chinook Salmon Captive Brood and Conventional Supplementation Programs, 2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hoffnagle, Timothy L.; Hair, Don; Carmichael, Richard W. (Oregon Department of Fish and Wildlife, La Grande, OR)

    2004-07-01

    BPA Fish and Wildlife Program Project Number 1998-01-001 provides funding for the Grande Ronde Basin Spring Chinook Salmon Captive Broodstock Program. This report satisfies the requirement that an annual report be submitted for FY 2003. The Grande Ronde Basin Spring Chinook Salmon Captive Broodstock Project is designed to rapidly increase numbers of salmon in stocks that are in imminent danger of extirpation. Parr are captured in Catherine Creek, upper Grande Ronde River and Lostine River and reared to adulthood in captivity. Upon maturation, these fish are spawned (within stocks) and their progeny reared to smoltification before being released into the natal stream of their parents. This program is co-managed by ODFW, National Marine Fisheries Service, Nez Perce Tribe and Confederated Tribes of the Umatilla Indian Reservation. This report covers activities conducted and provides data analyses for the Grande Ronde Spring Chinook Salmon Captive broodstock Program from 1 January--31 December 2003. Since the fiscal year ends in the middle of the spawning period, an annual report based on calendar year is more logical. This document is the FY 2003 annual report. Detailed information on historic and present population status, project background, goals and objectives, significance to regional programs and relationships to other programs, methods and previous results are available in the 1995-2002 Project Status Report (Hoffnagle et al 2003).

  6. Grande Ronde Basin Chinook Salmon Captive Brood and Conventional Supplementation Programs, 2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Carmichael, Richard W. (Oregon Department of Fish and Wildlife, La Grande, OR)

    2003-07-01

    Endangered Species Permit Number 1011 (formerly Permit No. 973) authorizes ODFW to take listed spring chinook salmon juveniles from Catherine Creek (CC), Lostine River (LR) and Grande Ronde River (GR) for research and enhancement purposes. Modification 2 of this permit authorizes ODFW to take adults for spawning and the production and release of smolts for the Captive and Conventional broodstock programs. This report satisfies the requirement that an annual report be submitted. Herein we report on activities conducted and provide cursory data analyses for the Grande Ronde spring chinook salmon Captive and Conventional broodstock projects from 1 January-31 December 2002. The Grande Ronde Basin Spring Chinook Salmon Captive Broodstock Project is designed to rapidly increase numbers of salmon in stocks that are in imminent danger of extirpation. Parr are captured in Catherine Creek, upper Grande Ronde River and Lostine River and reared to adulthood in captivity. Upon maturation, they are spawned (within stocks) and their progeny reared to smoltification before being released into the natal stream of their parents. This program is co-managed by ODFW, National Marine Fisheries Service, the Nez Perce Tribe and Confederated Tribes of the Umatilla Indian Reservation.

  7. Economics of endangered salmon in the Pacific northwest

    International Nuclear Information System (INIS)

    Hamilton, J.R.

    1993-01-01

    Under mandate of the Endangered Species Act (ESA), Idaho, Oregon and Washington are developing recovery plans to preserve several threatened and endangered stocks of salmon. These fish, some migrating as much as 900 miles inland to spawn, have been decimated by man's modification of their habitat. Downstream migrating juveniles must navigate through or around eight slackwater pools and hydropower dams. Adult upstream migrants must negotiate fish ladders, and endure modified temperature regimes and severely reduced spawning area and habitat quality. While the ESA says little about economics, economic factors do play important roles in designating endangered species and the design of recovery plans. For species in severe trouble ESA pushes us to drastic strategies such as captive breeding, or cryogenic sperm and egg preservation without paying much attention to whether the cost is worth it. For species in less dire straights, one often faces a menu of possible recovery actions from which the least cost can be set. Economics is important irrespective of the role it plays in decisions to classify salmon as endangered, or decisions about recovery plans. Economic analysis can provide those affected with information about their future. For individuals, communities, and businesses faced with adjusting to ESA actions, more good information is better than less, and economic impact estimates can be a valuable part of this information

  8. spawning grounds for chokka squid Loligo vulgaris reynaudii, using

    African Journals Online (AJOL)

    denise

    Swimming movements in relation to egg beds have been studied using acoustic micro-electronic transmitters implanted in squid and tracked via 3-D radio-linked acoustic positioning telemetry (O'Dor et al. 1996, 1998, Sauer et al. 1997). Most of these methods are either impractical or would be severely limited on the deeper ...

  9. Physiological consequences of the salmon louse (Lepeophtheirus salmonis) on juvenile pink salmon (Oncorhynchus gorbuscha): implications for wild salmon ecology and management, and for salmon aquaculture.

    Science.gov (United States)

    Brauner, C J; Sackville, M; Gallagher, Z; Tang, S; Nendick, L; Farrell, A P

    2012-06-19

    Pink salmon, Oncorhynchus gorbuscha, are the most abundant wild salmon species and are thought of as an indicator of ecosystem health. The salmon louse, Lepeophtheirus salmonis, is endemic to pink salmon habitat but these ectoparasites have been implicated in reducing local pink salmon populations in the Broughton Archipelago, British Columbia. This allegation arose largely because juvenile pink salmon migrate past commercial open net salmon farms, which are known to incubate the salmon louse. Juvenile pink salmon are thought to be especially sensitive to this ectoparasite because they enter the sea at such a small size (approx. 0.2 g). Here, we describe how 'no effect' thresholds for salmon louse sublethal impacts on juvenile pink salmon were determined using physiological principles. These data were accepted by environmental managers and are being used to minimize the impact of salmon aquaculture on wild pink salmon populations.

  10. Novel species interactions: American black bears respond to Pacific herring spawn.

    Science.gov (United States)

    Fox, Caroline Hazel; Paquet, Paul Charles; Reimchen, Thomas Edward

    2015-05-26

    In addition to the decline and extinction of the world's species, the decline and eventual loss of species interactions is one of the major consequences of the biodiversity crisis. On the Pacific coast of North America, diminished runs of salmon (Oncorhynchus spp.) drive numerous marine-terrestrial interactions, many of which have been intensively studied, but marine-terrestrial interactions driven by other species remain relatively unknown. Bears (Ursus spp.) are major vectors of salmon into terrestrial ecosystems, but their participation in other cross-ecosystem interactions is similarly poorly described. Pacific herring (Clupea pallasii), a migratory forage fish in coastal marine ecosystems of the North Pacific Ocean and the dominant forage fish in British Columbia (BC), spawn in nearshore subtidal and intertidal zones. Spawn resources (eggs, milt, and spawning adults) at these events are available to coastal predators and scavengers, including terrestrial species. In this study, we investigated the interaction between American black bears (Ursus americanus) and Pacific herring at spawn events in Quatsino Sound, BC, Canada. Using remote cameras to monitor bear activity (1,467 camera days, 29 sites, years 2010-2012) in supratidal and intertidal zones and a machine learning approach, we determined that the quantity of Pacific herring eggs in supratidal and intertidal zones was a leading predictor of black bear activity, with bears positively responding to increasing herring egg masses. Other important predictors included day of the year and Talitrid amphipod (Traskorchestia spp.) mass. A complementary analysis of black bear scats indicated that Pacific herring egg mass was the highest ranked predictor of egg consumption by bears. Pacific herring eggs constituted a substantial yet variable component of the early springtime diet of black bears in Quatsino Sound (frequency of occurrence 0-34%; estimated dietary content 0-63%). Other major dietary items included

  11. Brood Year 2004: Johnson Creek Chinook Salmon Supplementation Report, June 2004 through March 2006.

    Energy Technology Data Exchange (ETDEWEB)

    Gebhards, John S.; Hill, Robert; Daniel, Mitch [Nez Perce Tribe

    2009-02-19

    The Nez Perce Tribe, through funding provided by the Bonneville Power Administration, has implemented a small scale chinook salmon supplementation program on Johnson Creek, a tributary in the South Fork of the Salmon River, Idaho. The Johnson Creek Artificial Propagation Enhancement project was established to enhance the number of threatened Snake River spring/summer chinook salmon (Oncorhynchus tshawytscha) returning to Johnson Creek to spawn through artificial propagation. This was the sixth season of adult chinook broodstock collection in Johnson Creek following collections in 1998, 2000, 2001, 2002, and 2003. Weir installation was completed on June 21, 2004 with the first chinook captured on June 22, 2004 and the last fish captured on September 6, 2004. The weir was removed on September 18, 2004. A total of 338 adult chinook, including jacks, were captured during the season. Of these, 211 were of natural origin, 111 were hatchery origin Johnson Creek supplementation fish, and 16 were adipose fin clipped fish from other hatchery operations and therefore strays into Johnson Creek. Over the course of the run, 57 natural origin Johnson Creek adult chinook were retained for broodstock, transported to the South Fork Salmon River adult holding and spawning facility and held until spawned. The remaining natural origin Johnson Creek fish along with all the Johnson Creek supplementation fish were released upstream of the weir to spawn naturally. Twenty-seven Johnson Creek females were artificially spawned with 25 Johnson Creek males. Four females were diagnosed with high bacterial kidney disease levels resulting in their eggs being culled. The 27 females produced 116,598 green eggs, 16,531 green eggs were culled, with an average eye-up rate of 90.6% resulting in 90,647 eyed eggs. Juvenile fish were reared indoors at the McCall Fish Hatchery until November 2005 and then transferred to the outdoor rearing facilities during the Visual Implant Elastomer tagging operation

  12. Increased mitochondrial DNA diversity in ancient Columbia River basin Chinook salmon Oncorhynchus tshawytscha.

    Directory of Open Access Journals (Sweden)

    Bobbi M Johnson

    Full Text Available The Columbia River and its tributaries provide essential spawning and rearing habitat for many salmonid species, including Chinook salmon (Oncorhynchus tshawytscha. Chinook salmon were historically abundant throughout the basin and Native Americans in the region relied heavily on these fish for thousands of years. Following the arrival of Europeans in the 1800s, salmon in the basin experienced broad declines linked to overfishing, water diversion projects, habitat destruction, connectivity reduction, introgression with hatchery-origin fish, and hydropower development. Despite historical abundance, many native salmonids are now at risk of extinction. Research and management related to Chinook salmon is usually explored under what are termed "the four H's": habitat, harvest, hatcheries, and hydropower; here we explore a fifth H, history. Patterns of prehistoric and contemporary mitochondrial DNA variation from Chinook salmon were analyzed to characterize and compare population genetic diversity prior to recent alterations and, thus, elucidate a deeper history for this species. A total of 346 ancient and 366 contemporary samples were processed during this study. Species was determined for 130 of the ancient samples and control region haplotypes of 84 of these were sequenced. Diversity estimates from these 84 ancient Chinook salmon were compared to 379 contemporary samples. Our analysis provides the first direct measure of reduced genetic diversity for Chinook salmon from the ancient to the contemporary period, as measured both in direct loss of mitochondrial haplotypes and reductions in haplotype and nucleotide diversity. However, these losses do not appear equal across the basin, with higher losses of diversity in the mid-Columbia than in the Snake subbasin. The results are unexpected, as the two groups were predicted to share a common history as parts of the larger Columbia River Basin, and instead indicate that Chinook salmon in these subbasins

  13. Research on Captive Broodstock Programs for Pacific Salmon, 2001-2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Berejikian, Barry; Tezak, E.; Endicott, Rick

    2002-08-01

    The efficacy of captive broodstock programs depends on high in-culture survival and the fitness of cultured salmon after release, either as adults or juveniles. Continuing captive broodstock research designed to improve technology is being conducted to cover all major life history stages of Pacific salmon. The following summarizes some of the work performed and results from the FY 2001 performance period: (1) The incidence of male maturation of age-1 chinook salmon was significantly reduced by reducing growth in the first year of rearing. (2) Experimentally manipulated growth rates of captively-reared coho salmon had significant effects on female maturation rate, egg size, and fecundity, and the effects were stage-specific (i.e., pre-smolt vs. post-smolt). (3) A combination of Renogen and MT239 vaccination of yearling chinook salmon given an acute R. salmoninarum challenge had a significantly longer survival time than the mock-vaccinated group. The survival time was marginally higher than was seen in acutely challenged fish vaccinated with either Renogen or MT239 alone and suggests that a combination vaccine of Renogen and MT239 may be useful as both a prophylactic and therapeutic agent against BKD. (4) Full-sib (inbred) groups of chinook salmon have thus far exhibited lower ocean survival than half-sib and non-related groups. Effects of inbreeding on fluctuating asymmetry did not follow expected patterns. (5) Sockeye salmon were exposed to specific odorants at either the alevin/emergent fry stage or the smolt stage to determine the relative importance of odorant exposure during key developmental periods and the importance of exposure duration. (6) Experimental studies to determine the effects of exercise conditioning on steelhead reproductive behavior and the effects of male body size on chinook salmon fertilization success during natural spawning were completed.

  14. Increased mitochondrial DNA diversity in ancient Columbia River basin Chinook salmon Oncorhynchus tshawytscha.

    Science.gov (United States)

    Johnson, Bobbi M; Kemp, Brian M; Thorgaard, Gary H

    2018-01-01

    The Columbia River and its tributaries provide essential spawning and rearing habitat for many salmonid species, including Chinook salmon (Oncorhynchus tshawytscha). Chinook salmon were historically abundant throughout the basin and Native Americans in the region relied heavily on these fish for thousands of years. Following the arrival of Europeans in the 1800s, salmon in the basin experienced broad declines linked to overfishing, water diversion projects, habitat destruction, connectivity reduction, introgression with hatchery-origin fish, and hydropower development. Despite historical abundance, many native salmonids are now at risk of extinction. Research and management related to Chinook salmon is usually explored under what are termed "the four H's": habitat, harvest, hatcheries, and hydropower; here we explore a fifth H, history. Patterns of prehistoric and contemporary mitochondrial DNA variation from Chinook salmon were analyzed to characterize and compare population genetic diversity prior to recent alterations and, thus, elucidate a deeper history for this species. A total of 346 ancient and 366 contemporary samples were processed during this study. Species was determined for 130 of the ancient samples and control region haplotypes of 84 of these were sequenced. Diversity estimates from these 84 ancient Chinook salmon were compared to 379 contemporary samples. Our analysis provides the first direct measure of reduced genetic diversity for Chinook salmon from the ancient to the contemporary period, as measured both in direct loss of mitochondrial haplotypes and reductions in haplotype and nucleotide diversity. However, these losses do not appear equal across the basin, with higher losses of diversity in the mid-Columbia than in the Snake subbasin. The results are unexpected, as the two groups were predicted to share a common history as parts of the larger Columbia River Basin, and instead indicate that Chinook salmon in these subbasins may have divergent

  15. Increased mitochondrial DNA diversity in ancient Columbia River basin Chinook salmon Oncorhynchus tshawytscha

    Science.gov (United States)

    Kemp, Brian M.; Thorgaard, Gary H.

    2018-01-01

    The Columbia River and its tributaries provide essential spawning and rearing habitat for many salmonid species, including Chinook salmon (Oncorhynchus tshawytscha). Chinook salmon were historically abundant throughout the basin and Native Americans in the region relied heavily on these fish for thousands of years. Following the arrival of Europeans in the 1800s, salmon in the basin experienced broad declines linked to overfishing, water diversion projects, habitat destruction, connectivity reduction, introgression with hatchery-origin fish, and hydropower development. Despite historical abundance, many native salmonids are now at risk of extinction. Research and management related to Chinook salmon is usually explored under what are termed “the four H’s”: habitat, harvest, hatcheries, and hydropower; here we explore a fifth H, history. Patterns of prehistoric and contemporary mitochondrial DNA variation from Chinook salmon were analyzed to characterize and compare population genetic diversity prior to recent alterations and, thus, elucidate a deeper history for this species. A total of 346 ancient and 366 contemporary samples were processed during this study. Species was determined for 130 of the ancient samples and control region haplotypes of 84 of these were sequenced. Diversity estimates from these 84 ancient Chinook salmon were compared to 379 contemporary samples. Our analysis provides the first direct measure of reduced genetic diversity for Chinook salmon from the ancient to the contemporary period, as measured both in direct loss of mitochondrial haplotypes and reductions in haplotype and nucleotide diversity. However, these losses do not appear equal across the basin, with higher losses of diversity in the mid-Columbia than in the Snake subbasin. The results are unexpected, as the two groups were predicted to share a common history as parts of the larger Columbia River Basin, and instead indicate that Chinook salmon in these subbasins may have

  16. Johnson Creek Artificial Propagation and Enhancement Project Operations and Maintenance Program; Brood Year 1998: Johnson Creek Chinook Salmon Supplementation, Biennial Report 1998-2000.

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, Mitch; Gebhards, John

    2003-05-01

    The Nez Perce Tribe, through funding provided by the Bonneville Power Administration, has implemented a small scale chinook salmon supplementation program on Johnson Creek, a tributary in the South Fork of the Salmon River, Idaho. The Johnson Creek Artificial Propagation Enhancement project was established to enhance the number of threatened Snake River summer chinook salmon (Oncorhynchus tshawytscha) returning to Johnson Creek through artificial propagation. Adult chinook salmon collection and spawning began in 1998. A total of 114 fish were collected from Johnson Creek and 54 fish (20 males and 34 females) were retained for Broodstock. All broodstock were transported to Lower Snake River Compensation Plan's South Fork Salmon River adult holding and spawning facility, operated by the Idaho Department of Fish and Game. The remaining 60 fish were released to spawn naturally. An estimated 155,870 eggs from Johnson Creek chinook spawned at the South Fork Salmon River facility were transported to the McCall Fish Hatchery for rearing. Average fecundity for Johnson Creek females was 4,871. Approximately 20,500 eggs from females with high levels of Bacterial Kidney Disease were culled. This, combined with green-egg to eyed-egg survival of 62%, resulted in about 84,000 eyed eggs produced in 1998. Resulting juveniles were reared indoors at the McCall Fish Hatchery in 1999. All of these fish were marked with Coded Wire Tags and Visual Implant Elastomer tags and 8,043 were also PIT tagged. A total of 78,950 smolts were transported from the McCall Fish Hatchery and released directly into Johnson Creek on March 27, 28, 29, and 30, 2000.

  17. Accounting for risk conflicts in Scottish salmon farming

    NARCIS (Netherlands)

    Georgakopoulos, G.; Thomson, I.; Kaldis, P.

    2008-01-01

    Purpose: To offer a theoretical analysis, inspired by contemporary research into risk, of the social and environmental accounting processes observed in an empirical study on Scottish salmon farming. Methodology / Approach: This paper used a Grounded Theory approach. Empirical evidence was collected

  18. Pyrethroid insecticides in urban salmon streams of the Pacific Northwest

    Energy Technology Data Exchange (ETDEWEB)

    Weston, D.P., E-mail: dweston@berkeley.edu [Department of Integrative Biology, University of California, 3060 Valley Life Sciences Bldg., Berkeley, CA 94720-3140 (United States); Asbell, A.M., E-mail: aasbell@berkeley.edu [Department of Integrative Biology, University of California, 3060 Valley Life Sciences Bldg., Berkeley, CA 94720-3140 (United States); Hecht, S.A., E-mail: scott.hecht@noaa.gov [NOAA Fisheries, Office of Protected Resources, 510 Desmond Drive S.E., Lacey, WA 98503 (United States); Scholz, N.L., E-mail: nathaniel.scholz@noaa.gov [NOAA Fisheries, Northwest Fisheries Science Center, 2725 Montlake Blvd. E., Seattle, WA 98112 (United States); Lydy, M.J., E-mail: mlydy@siu.edu [Fisheries and Illinois Aquaculture Center and Department of Zoology, Southern Illinois University, 171 Life Sciences II, Carbondale, IL 62901 (United States)

    2011-10-15

    Urban streams of the Pacific Northwest provide spawning and rearing habitat for a variety of salmon species, and food availability for developing salmon could be adversely affected by pesticide residues in these waterbodies. Sediments from Oregon and Washington streams were sampled to determine if current-use pyrethroid insecticides from residential neighborhoods were reaching aquatic habitats, and if they were at concentrations acutely toxic to sensitive invertebrates. Approximately one-third of the 35 sediment samples contained measurable pyrethroids. Bifenthrin was the pyrethroid of greatest concern with regards to aquatic life toxicity, consistent with prior studies elsewhere. Toxicity to Hyalella azteca and/or Chironomus dilutus was found in two sediment samples at standard testing temperature (23 deg. C), and in one additional sample at a more environmentally realistic temperature (13 deg. C). Given the temperature dependency of pyrethroid toxicity, low temperatures typical of northwest streams can increase the potential for toxicity above that indicated by standard testing protocols. - Highlights: > Salmon-bearing creeks can be adversely impacted by insecticides from urban runoff. > Pyrethroid insecticides were found in one-third of the creeks in Washington and Oregon. > Two creeks contained concentrations acutely lethal to sensitive invertebrates. > Bifenthrin was of greatest concern, though less than in prior studies. > Standard toxicity testing underestimates the ecological risk of pyrethroids. - Pyrethroid insecticides are present in sediments of urban creeks of Oregon and Washington, though less commonly than in studies elsewhere in the U.S.

  19. Broadcast spawning by Pocillopora species on the Great Barrier Reef.

    Science.gov (United States)

    Schmidt-Roach, Sebastian; Miller, Karen J; Woolsey, Erika; Gerlach, Gabriele; Baird, Andrew H

    2012-01-01

    The coral genus Pocillopora is one of the few to include some species that broadcast spawn gametes and some species that brood larvae, although reports of reproductive mode and timing vary within and among species across their range. Notably, the ubiquitous Pocillopora damicornis has been described as both a brooder and spawner, although evidence of broadcast spawning is rare. Here, we report observations of broadcast-spawning in four species of Pocillopora on the Great Barrier Reef (GBR), including P. damicornis. All species spawned predictably during the early morning, two days following the full moon, and spawning was observed in multiple months over the summer period (November to February). Eggs and sperm were free-spawned concurrently. Eggs were negatively buoyant and contained Symbiodinium. This newfound knowledge on the mode, timing and regularity of broadcast spawning in Pocillopora spp. on the GBR brings us one step closer to elucidating the complex reproductive ecology of these species.

  20. Mature male parr contribution to the effective size of an anadromous Atlantic salmon (Salmo salar) population over 30 years.

    Science.gov (United States)

    Johnstone, Devon L; O'Connell, Michael F; Palstra, Friso P; Ruzzante, Daniel E

    2013-05-01

    We describe temporal changes in the genetic composition of a small anadromous Atlantic salmon (Salmo salar) population from South Newfoundland, an area where salmon populations are considered threatened (COSEWIC 2010). We examined the genetic variability (13 microsatellite loci) in 869 out-migrating smolt and post-spawning kelt samples, collected from 1985 to 2011 for a total of 22 annual collections and a 30 year span of assigned cohorts. We estimated the annual effective number of breeders (Nb) and the generational effective population size (Ne) through genetic methods and demographically using the adult sex ratio. Comparisons between genetic and demographic estimates show that the adult spawners inadequately explain the observed Ne estimates, suggesting that mature male parr are significantly increasing Nb and Ne over the study period. Spawning as parr appears to be a viable and important strategy in the near absence of adult males. © 2013 Blackwell Publishing Ltd.

  1. The importance of genetic verification for determination of Atlantic salmon in north Pacific waters

    Science.gov (United States)

    Nielsen, J.L.; Williams, I.; Sage, G.K.; Zimmerman, C.E.

    2003-01-01

    Genetic analyses of two unknown but putative Atlantic salmon Salmo salar captured in the Copper River drainage, Alaska, demonstrated the need for validation of morphologically unusual fishes. Mitochondrial DNA sequences (control region and cytochrome b) and data from two nuclear genes [first internal transcribed spacer (ITS-1) sequence and growth hormone (GH1) amplification product] indicated that the fish caught in fresh water on the Martin River was a coho salmon Oncorhynchus kisutch, while the other fish caught in the intertidal zone of the Copper River delta near Grass Island was an Atlantic salmon. Determination of unusual or cryptic fish based on limited physical characteristics and expected seasonal spawning run timing will add to the controversy over farmed Atlantic salmon and their potential effects on native Pacific species. It is clear that determination of all putative collections of Atlantic salmon found in Pacific waters requires validation. Due to uncertainty of fish identification in the field using plastic morphometric characters, it is recommended that genetic analyses be part of the validation process. ?? 2003 The Fisheries Society of the British Isles.

  2. Research on Captive Broodstock Programs for Pacific Salmon, 2004-2005 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Berejikian, Barry A. (National Marine Fisheries Service)

    2005-11-01

    The success of captive broodstock programs depends on high in-culture survival, appropriate development of the reproductive system, and the behavior and survival of cultured salmon after release, either as adults or juveniles. Continuing captive broodstock research designed to improve technology is being conducted to cover all major life history stages of Pacific salmon. Accomplishments detailed in this report and those since the last project review period (FY 2003) are listed below by major objective. Objective 1: (i) Developed tools for monitoring the spawning success of captively reared Chinook salmon that can now be used for evaluating the reintroduction success of ESA-listed captive broodstocks in their natal habitats. (ii) Developed an automated temperature controlled rearing system to test the effects of seawater rearing temperature on reproductive success of Chinook salmon. Objective 2: (i) Determined that Columbia River sockeye salmon imprint at multiple developmental stages and the length of exposure to home water is important for successful imprinting. These results can be utilized for developing successful reintroduction strategies to minimize straying by ESA-listed sockeye salmon. (ii) Developed behavioral and physiological assays for imprinting in sockeye salmon. Objective 3: (i) Developed growth regime to reduce age-two male maturation in spring Chinook salmon, (ii) described reproductive cycle of returning hatchery Snake River spring Chinook salmon relative to captive broodstock, and (iii) found delays in egg development in captive broodstock prior to entry to fresh water. (iv) Determined that loss of Redfish Lake sockeye embryos prior to hatch is largely due to lack of egg fertilization rather than embryonic mortality. Objective 4 : (i) Demonstrated safety and efficacy limits against bacterial kidney disease (BKD) in fall Chinook of attenuated R. salmoninarum vaccine and commercial vaccine Renogen, (ii) improved prophylactic and therapeutic

  3. Snake River Sockeye Salmon Captive Broodstock Program; Research Element, 2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Willard, Catherine; Hebdon, J. Lance; Castillo, Jason (Idaho Department of Fish and Game, Boise, ID)

    2004-06-01

    On November 20, 1991, the National Oceanic Atmospheric Administration listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. In 1991, the Shoshone-Bannock Tribes and Idaho Department of Fish and Game initiated the Snake River Sockeye Salmon Sawtooth Valley Project to conserve and rebuild populations in Idaho. Restoration efforts are focusing on Redfish, Pettit, and Alturas lakes within the Sawtooth Valley. The first release of hatchery-produced juvenile sockeye salmon from the captive broodstock program occurred in 1994. The first anadromous adult returns from the captive broodstock program were recorded in 1999 when six jacks and one jill were captured at IDFG's Sawtooth Fish Hatchery. In 2002, progeny from the captive broodstock program were released using four strategies: age-0 presmolts were released to Alturas, Pettit, and Redfish lakes in August and to Pettit and Redfish lakes in October, age-1 smolts were released to Redfish Lake Creek in May, eyed-eggs were planted in Pettit Lake in December, and hatchery-produced and anadromous adult sockeye salmon were released to Redfish Lake for volitional spawning in September. Oncorhynchus nerka population monitoring was conducted on Redfish, Alturas, and Pettit lakes using a midwater trawl in September 2002. Age-0, age-1, and age-2 O. nerka were captured in Redfish Lake, and population abundance was estimated at 50,204 fish. Age-0, age-1, age-2, and age-3 kokanee were captured in Alturas Lake, and population abundance was estimated at 24,374 fish. Age-2 and age-3 O. nerka were captured in Pettit Lake, and population abundance was estimated at 18,328 fish. The ultimate goal of the Idaho Department of Fish and Game (IDFG) captive broodstock development and evaluation efforts is to recover sockeye salmon runs in Idaho waters. Recovery is defined as reestablishing sockeye salmon runs and providing for utilization of sockeye salmon and kokanee resources by anglers

  4. Snake River Sockeye Salmon Captive Broodstock Program; Hatchery Element, 2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Baker, Dan J.; Heindel, Jeff A.; Redding, Jeremy (Idaho Department of Fish and Game, Boise, ID)

    2006-05-01

    On November 20, 1991, the National Marine Fisheries Service listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. In 1991, the Idaho Department of Fish and Game, the Shoshone-Bannock Tribes, and the National Marine Fisheries Service initiated efforts to conserve and rebuild populations in Idaho. Initial steps to recover sockeye salmon included the establishment of a captive broodstock program at the Idaho Department of Fish and Game Eagle Fish Hatchery. Sockeye salmon broodstock and culture responsibilities are shared with the National Oceanic and Atmospheric Administration at two locations adjacent to Puget Sound in Washington State. Activities conducted by the Shoshone-Bannock Tribes and the National Oceanic and Atmospheric Administration are reported under separate cover. Idaho Department of Fish and Game monitoring and evaluation activities of captive broodstock program fish releases (annual report to the Bonneville Power Administration for the research element of the program) are also reported separately. Captive broodstock program activities conducted between January 1, 2004 and December 31, 2004 for the hatchery element of the program are presented in this report. In 2004, twenty-seven anadromous sockeye salmon returned to the Sawtooth Valley. Traps on Redfish Lake Creek and the upper Salmon River at the Sawtooth Fish Hatchery intercepted one and four adults, respectively. Additionally, one adult sockeye salmon was collected at the East Fork Salmon River weir, 18 were seined from below the Sawtooth Fish Hatchery weir, one adult sockeye salmon was observed below the Sawtooth Fish Hatchery weir but not captured, and two adult sockeye salmon were observed in Little Redfish Lake but not captured. Fish were captured/collected between July 24 and September 14, 2004. The captured/collected adult sockeye salmon (12 females and 12 males) originated from a variety of release strategies and were transferred to

  5. Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2003 Smolt Acclimation and Adult Return Report.

    Energy Technology Data Exchange (ETDEWEB)

    Zollman, Richard L.; Eschler, Russell; Sealey, Shawn [Nez Perce Tribe

    2009-03-31

    The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the seventh season (1997-2003) of adult Chinook salmon broodstock collection in the Lostine River and the fifth season (1999-2003) of acclimating the resultant progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1) capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progeny for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies. In 2003, acclimation of

  6. Assessment of lake sturgeon (Acipenser fulvescens) spawning efforts in the lower St. Clair River, Michigan

    Science.gov (United States)

    Nichols, S. Jerrine; Kennedy, Gregory; Crawford, Eric; Allen, Jeffrey; French, John; Black, Glen; Blouin, Marc; Hickey, James P.; Chernyak, Sergei; Haas, Robert; Thomas, Michael

    2003-01-01

    One of the most threatened remaining populations of lake sturgeon in the Great Lakes is found in the connecting channels between Lake Huron and Lake Erie. Only two spawning grounds are presently known to be active in this region, and both are in the St. Clair River. The spawning reef in the St. Clair River delta has been recently colonized by round gobies (Neogobius melanostomus) in densities up to 25/m2, raising concerns regarding predation on the benthic-oriented eggs and larvae of the sturgeon. Investigations in 1998–1999 showed that while round goby predation does occur, a number of other factors may be equally affecting sturgeon spawning success, including few spawning adults (noted in either year. There were factors other than predation affecting larval survival in 1999. There was a higher silt load on the reef than in 1998 and large numbers of dead larvae were found. Recruitment success from this site could be improved by utilizing techniques to increase the number of eggs on the reef, such as reducing the illegal take of adult fish and by placing eggs in predator-exclusion chambers to increase hatch rate.

  7. Hatching time and alevin growth prior to the onset of exogenous feeding in farmed, wild and hybrid Norwegian Atlantic salmon.

    Directory of Open Access Journals (Sweden)

    Monica Favnebøe Solberg

    Full Text Available The onset of exogenous feeding, when juveniles emerge from the gravel, is a critical event for salmonids where early emergence and large size provide a competitive advantage in the wild. Studying 131 farmed, hybrid and wild Norwegian Atlantic salmon families, originating from four wild populations and two commercial strains, we investigated whether approximately 10 generations of selection for faster growth has also resulted in increased somatic growth prior to the onset of exogenous feeding. In addition, we tested whether relaxed selection in farms has allowed for alterations in hatching time between farmed and wild salmon. Across three cohorts, wild salmon families hatched earlier than farmed salmon families, while hybrid families displayed intermediate hatching times. While the observed differences were small, i.e., 1-15 degree-days (0-3 days, as water temperatures were c. 5-6°C, these data suggest additive genetic variation for hatching time. Alevin length prior to exogenous feeding was positively related to egg size. After removal of egg size effects, no systematic differences in alevin length were observed between the wild and farmed salmon families. While these results indicate additive genetic variation for egg development timing, and wild salmon families consistently hatched earlier than farmed salmon families, these differences were so small they are unlikely to significantly influence early life history competition of farmed and wild salmon in the natural environment. This is especially the case given that the timing of spawning among females can vary by several weeks in some rivers. The general lack of difference in size between farmed and wild alevins, strongly suggest that the documented differences in somatic growth rate between wild and farmed Norwegian Atlantic salmon under hatchery conditions are first detectable after the onset of exogenous feeding.

  8. Vulnerability of Fraser River sockeye salmon to climate change: a life cycle perspective using expert judgments.

    Science.gov (United States)

    McDaniels, Tim; Wilmot, Sarah; Healey, Michael; Hinch, Scott

    2010-12-01

    Fraser River sockeye salmon have been the basis for a major commercial fishery shared by Canada and the United States, and an important cultural foundation for many aboriginal groups; they are also of huge ecological significance throughout the Fraser Basin. The potential for altered aquatic habitat and temperature regimes due to climate change is an important concern for Fraser River sockeye salmon. This paper characterizes the vulnerability of Fraser River sockeye salmon to future climate change using an approach that is novel on three counts. First, previous efforts to assess the vulnerability of salmon to climate change have largely focused on only part of the life cycle, whereas we consider climate vulnerability at all stages in the life cycle. Second, we use the available scientific literature to provide a basis for structuring and eliciting judgments from fisheries science and management experts who research and manage these systems. Third, we consider prospects for mitigating the effects of climate change on sockeye salmon. Tests showed that participants' judgments differentiated in statistically significant ways among questions that varied in terms of life stages, spawning regions and climate scenarios. The consensus among participants was that Fraser River sockeye are most vulnerable to climate change during the egg and returning adult stages of the life cycle. A high temperature scenario was seen as imposing the greatest risk on sockeye stocks, particularly those that migrate to the upper reaches of the Fraser River system and spawn earlier in the summer. The inability to alter water temperature and the highly constrained nature of sockeye management, with competing gear types and sequential fisheries over a long distance, suggest the potential to mitigate adverse effects is limited. Fraser River sockeye already demonstrate a great deal of adaptive capacity in utilizing heterogeneous habitats in different river sub-basins. This adaptability points to the

  9. Biotic and abiotic influences on abundance and distribution of nonnative Chinook salmon and native ESA-listed steelhead in the Wind River, Washington

    Science.gov (United States)

    Jezorek, Ian G.; Connolly, Patrick J.

    2015-01-01

    Biotic and abiotic factors influence fish populations and distributions. Concerns have been raised about the influence of hatchery fish on wild populations. Carson National Fish Hatchery produces spring Chinook salmon Oncorhynchus tshawytscha in the Wind River, Washington, and some spawn in the river. Managers were concerned that Chinook salmon could negatively affect wild steelhead O. mykiss and that a self-sustaining population of Chinook salmon may develop. Our objectives were to assess: 1) the distribution and populations of juvenile spring Chinook salmon and juvenile steelhead in the upper Wind River; 2) the influence of stream flow and of each population on the other; and 3) if Chinook salmon populations were self-sustaining. We snorkeled to determine distribution and abundance. Flow in the fall influenced upstream distribution and abundance of juvenile Chinook salmon. Juvenile Chinook salmon densities were consistently low (range 0.0 to 5.7 fish 100 m-2) and not influenced by number of spawners, winter flow magnitude, or steelhead abundance. Juvenile steelhead were distributed through the study section each year. Age-0 and age-1 steelhead densities (age-0 range: 0.04 to 37.0 fish 100 m-2; age-1 range: 0.02 to 6.21 fish 100 m-2) were consistently higher than for juvenile Chinook salmon. Steelhead spawner abundance positively influenced juvenile steelhead abundance. During this study, Chinook salmon in the Wind River appear to have had little effect on steelhead. Low juvenile Chinook salmon abundance and a lack of a spawner-to-juvenile relationship suggest Chinook salmon are not self-sustaining and potential for such a population is low under current conditions.

  10. Migration trends of Sockeye Salmon at the northern edge of their distribution

    Science.gov (United States)

    Carey, Michael P.; Zimmerman, Christian E.; Keith, Kevin D.; Schelske, Merlyn; Lean, Charles; Douglas, David C.

    2017-01-01

    Climate change is affecting arctic and subarctic ecosystems, and anadromous fish such as Pacific salmon Oncorhynchus spp. are particularly susceptible due to the physiological challenge of spawning migrations. Predicting how migratory timing will change under Arctic warming scenarios requires an understanding of how environmental factors drive salmon migrations. Multiple mechanisms exist by which environmental conditions may influence migrating salmon, including altered migration cues from the ocean and natal river. We explored relationships between interannual variability and annual migration timing (2003–2014) of Sockeye Salmon O. nerka in a subarctic watershed with environmental conditions at broad, intermediate, and local spatial scales. Low numbers of Sockeye Salmon have returned to this high-latitude watershed in recent years, and run size has been a dominant influence on the migration duration and the midpoint date of the run. The duration of the migration upriver varied by as much as 25 d across years, and shorter run durations were associated with smaller run sizes. The duration of the migration was also extended with warmer sea surface temperatures in the staging area and lower values of the North Pacific Index. The midpoint date of the total run was earlier when the run size was larger, whereas the midpoint date was delayed during years in which river temperatures warmed earlier in the season. Documenting factors related to the migration of Sockeye Salmon near the northern limit of their range provides insights into the determinants of salmon migrations and suggests processes that could be important for determining future changes in arctic and subarctic ecosystems.

  11. Salmon tracing: Genotyping to trace back escapees from salmon aquaculture

    NARCIS (Netherlands)

    Blonk, R.J.W.

    2014-01-01

    The overall objective of the project is to assign an escaped salmon back to the farm responsible for the escape with near 100% accuracy. In this report, the potential of a set of genetic markers to assign an escaped salmon was determined for a set of 12 polymorphic microsatellite markers, provided

  12. The North Sea autumn spawning herring (Clupea harengus L.) Spawning Component Abundance Index (SCAI)

    DEFF Research Database (Denmark)

    2013-01-01

    The North Sea autumn-spawning herring (Clupea harengus) stock consists of a set of different spawning components. The dynamics of the entire stock have been well characterized, but although time-series of larval abundance indices are available for the individual components, study of the dynamics...... the other components, whereas the Downs component has been the slowest. These differences give rise to changes in stock composition, which are shown to vary widely within a relatively short time. The modelling framework provides a valuable tool for studying and monitoring the dynamics of the individual...... components of the North Sea herring stock...

  13. Cle Elum Lake Sockeye Salmon Restoration Feasibility Study, 1986-1988 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Flagg, Thomas A.

    1988-10-01

    In 1986, a multi-year project to evaluate the biological feasibility of reestablishing anadromous sockeye salmon (Oncorhynchus nerka) runs to Cle Elum Lake in the Yakima River Basin was established between the Bonneville Power Administration (BPA) and the National Marine Fisheries Service (NMFS). This program involves the capture, spawning, and rearing of disease-free donor stock in 1987 and 1988 and assessment of juvenile outmigration and survival from Cle Elum Lake in 1989 and 1990. Work in 1987--1988 involved collection of adult sockeye salmon from the Lake Wenatchee run and incubation and rearing of progeny as donor stock. In July 1987, 263 adults were captured at the Dryden fishway on the Wenatchee River and transferred to net-pens in Lake Wenatchee. Adults were held approximately 90 days and spawned, and the eggs were transferred to a quarantine hatchery. Pre-spawning survival was 95.1%, and all spawners were certified as being free of Infectious Hematopoietic Necrosis (IHN) and other replicating viruses. Egg viability averaged about 40%; however, eyed egg to hatch survival was over 99%. Juveniles are being reared in quarantine, and survival to date is about 92%. The NMFS currently has over 131,000 fry (0.7 g average weight) in culture. Fry have been certified twice (at 0.12 g and 0.25 g average weight) as being free of IHN and other replicating viruses. Viral certification will continue throughout rearing. 13 refs., 4 figs., 3 tabs.

  14. Research on Captive Broodstock Programs for Pacific Salmon, 2001-2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Berejikian, Barry A.; Tezak, E.P. (National Marine Fisheries Service); Endicott, Rick (Long Live the Kings, Seattle, WA)

    2002-08-01

    In the 2000 Federal Columbia River Power System (FCRPS) Biological Opinion, NMFS identified six populations of steelhead and several salmon populations that had dropped to critically low levels and continue to decline. Following thorough risk-benefit analyses, captive propagation programs for some or all of the steelhead (Oncorhynchus mykiss) populations may be required to reduce the risk of extinction, and more programs may be required in the future. Thus, captive propagation programs designed to maintain or rebuild steelhead populations require intensive and rigorous scientific evaluation, much like the other objectives of BPA Project 1993-056-00 currently underway for chinook (O. tshawytscha) and sockeye salmon (O. nerka). Pacific salmon reared to the adult stage in captivity exhibit poor reproductive performance when released to spawn naturally. Poor fin quality and swimming performance, incomplete development of secondary sex characteristics, changes in maturation timing, and other factors may contribute to reduced spawning success. Improving natural reproductive performance is critical for the success of captive broodstock programs in which adult-release is a primary reintroduction strategy for maintaining ESA-listed populations.

  15. Snake River sockeye salmon habitat and limnological research, annual report 1998

    International Nuclear Information System (INIS)

    Lewis, Bert

    2000-01-01

    In March of 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list the Snake River sockeye salmon (Oncorhynchus nerka) as endangered. As a result of that petition the Snake River sockeye salmon was officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991 the Snake River Sockeye Salmon Habitat and Limnological Research Program was implemented (Project Number 91-71, Intergovernmental Contract Number DE-BI79-91bp22548). This project is part of an inter-agency effort to save the Redfish Lake stock of O. nerka from extinction. This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the calendar year of 1998. Project objectives included; (1) monitor over-winter survival and emigration of juvenile anadromous O. nerka released from the captive rearing program into Pettit and Alturas lakes; (2) fertilize Redfish, Pettit, and Alturas lakes; (3) conduct kokanee (non-anadromous O. nerka) population surveys; (4) monitor spawning kokanee escapement and estimate fry recruitment on Fishhook, Alturas Lake, and Stanley Lake creeks; (5) control the number of spawning kokanee in Fishhook Creek; (6) evaluate potential competition and predation between stocked juvenile O. nerka and a variety of fish species in Redfish, Pettit, and Alturas lakes; (7) monitor limnological parameters of Sawtooth Valley lakes to assess lake productivity. Results by objective are summarized

  16. Timing of neurodegeneration and beta-amyloid (Abeta) peptide deposition in the brain of aging kokanee salmon.

    Science.gov (United States)

    Maldonado, Tammy A; Jones, Richard E; Norris, David O

    2002-10-01

    Brains of kokanee salmon (Oncorhynchus nerka kennerlyi) in one of four reproductive stages (sexually immature, maturing, sexually mature, and spawning) were stained with cresyl violet and silver stain to visualize neurodegeneration. These reproductive stages correlate with increasing somatic aging of kokanee salmon, which die after spawning. Twenty-four regions of each brain were examined. Brains of sexually immature fish exhibited low levels of neurodegeneration, whereas neurodegeneration was more marked in maturing fish and greatest in spawning fish. Neurodegeneration was present in specific regions of the telencephalon, diencephalon, mesencephalon, and rhombencephalon. Pyknotic neurons were observed in all regions previously reported to be immunopositive for A beta. Regions that did not exhibit neurodegeneration during aging included the magnocellular vestibular nucleus, the nucleus lateralis tuberis of the hypothalamus, and Purkinje cells of the cerebellum, all of which also lack A beta; perhaps these regions are neuroprotected. In 14 of 16 brain areas for which data were available on both the increase in A beta deposition and pyknosis, neurodegeneration preceded or appeared more or less simultaneously with A beta production, whereas in only two regions did A beta deposition precede neurodegeneration. This information supports the hypothesis that A beta deposition is a downstream product of neurodegeneration in most brain regions. Other conclusions are that the degree of neurodegeneration varies among brain regions, neurodegeneration begins in maturing fish and peaks in spawning fish, the timing of neurodegeneration varies among brain regions, and some regions do not exhibit accelerated neurodegeneration during aging. Copyright 2002 Wiley Periodicals, Inc.

  17. Spawning and Larval Development Dog Conch (Strombus Turturella)

    OpenAIRE

    Dody, Safar

    2012-01-01

    Dog conch (Strombus turturella) is considered one of fishery commodities in Bangka Belitung Islands. This conch is often exploited and result in their populations are increasingly threatened. The aim of study to observe the reproduction and larval development of dog conch were studied under laboratory conditions. For the treatment of spawning the dog conch were placed in spawning tanks with a capacity of 1 ton. Stimulation of spawning is done by replacing the water in the tank as much as 90% ...

  18. Habitat connectivity as a metric for aquatic microhabitat quality: Application to Chinook salmon spawning habitat

    Science.gov (United States)

    Ryan Carnie; Daniele Tonina; Jim McKean; Daniel Isaak

    2016-01-01

    Quality of fish habitat at the scale of a single fish, at the metre resolution, which we defined here as microhabitat, has been primarily evaluated on short reaches, and their results have been extended through long river segments with methods that do not account for connectivity, a measure of the spatial distribution of habitat patches. However, recent...

  19. Factors influencing the spawning migration of female anadromous brown trout

    DEFF Research Database (Denmark)

    Svendsen, Jon Christian; Koed, Anders; Aarestrup, Kim

    2004-01-01

    ' occurred under conditions of similar water temperature and stream discharge. Manual tracking indicated that in the pre-spawning state, the distance migrated over 3 days was positively correlated with stream discharge and water temperature, whereas in the post-spawning state, the total distance migrated......Radio telemetry was employed to study movements of adult female anadromous brown trout Salmo trutta (sea trout) during upstream spawning migration and following spawning in a stream with tributaries. Sea trout were monitored by manual tracking and by automatic listening stations. The latter...

  20. Skipped spawning in fishes: More common than you might think

    DEFF Research Database (Denmark)

    Rideout, Rick M.; Tomkiewicz, Jonna

    2011-01-01

    The traditional view of iteroparity in fishes is one of an annual reproductive cycle that culminates each year in spawning. More recently, a more flexible view of fish reproduction has been adopted, including the potential for mature fish to skip spawning. Here, we review the abundance of recent...... on elemental and isotope signatures. Skipped spawning is most commonly attributed to deficient diet and poor nutritional condition. Advances made in this field of study in recent years include descriptions of hormonal changes that precede and perhaps initiate skipped spawning, the development of life history...

  1. Biannual Spawning and Temporal Reproductive Isolation in Acropora Corals.

    Directory of Open Access Journals (Sweden)

    James P Gilmour

    Full Text Available Coral spawning on the oceanic reef systems of north-western Australia was recently discovered during autumn and spring, but the degree to which species and particularly colonies participated in one or both of these spawnings was unknown. At the largest of the oceanic reef systems, the participation by colonies in the two discrete spawning events was investigated over three years in 13 species of Acropora corals (n = 1,855 colonies. Seven species spawned during both seasons; five only in autumn and one only in spring. The majority of tagged colonies (n = 218 spawned once a year in the same season, but five colonies from three species spawned during spring and autumn during a single year. Reproductive seasonality was not influenced by spatial variation in habitat conditions, or by Symbiodinium partners in the biannual spawner Acropora tenuis. Colonies of A. tenuis spawning during different seasons separated into two distinct yet cryptic groups, in a bayesian clustering analysis based on multiple microsatellite markers. These groups were associated with a major genetic divergence (G"ST = 0.469, despite evidence of mixed ancestry in a small proportion of individuals. Our results confirm that temporal reproductive isolation is a common feature of Acropora populations at Scott Reef and indicate that spawning season is a genetically determined trait in at least A. tenuis. This reproductive isolation may be punctuated occasionally by interbreeding between genetic groups following favourable environmental conditions, when autumn spawners undergo a second annual gametogenic cycle and spawn during spring.

  2. Induced spawning, survival and growth of an African catfish hybrid ...

    African Journals Online (AJOL)

    Induced spawning, survival and growth of an African catfish hybrid (female Clarias gariepinus and male Clarias anguillaris ) fingerlings relative to their parental species in the mount Cameroon region.

  3. Consecutive spawnings of Chinese amphioxus, Branchiostoma belcheri, in captivity.

    Directory of Open Access Journals (Sweden)

    Guang Li

    Full Text Available Cephalochordate amphioxus is a promising model animal for studying the evolutionary and developmental mechanisms of vertebrates because its unique phylogenetic position, simple body plan and sequenced genome. However, one major drawback for using amphioxus as a model organism is the restricted supply of living embryos since they are available only during spawning season that varies from a couple of days to several months according to species. Therefore we are aiming to develop methods for obtaining viable amphioxus embryos in non-spawning season. In the current study, we found that Branchiostoma belcheri could develop their gonads and spawn consecutively in the laboratory when cultured in a low density at a high temperature (25-28 °C supplied with sufficient food and proper cleanness. Among the approximate 150 observed animals, which spawned spontaneously between November and December 2011, 10% have spawned twice, 10% three times, and 80% four times, through April 2012. The quality and quantity of the gametes reproduced in the consecutive spawning have no obvious difference with those spawned once naturally. Spawning intervals varied dramatically both among different animals (from 1 to 5 months and between intervals of a single individual (from 27 to 74 days for one animal. In summary, we developed a method with which, for the first time, consecutive spawnings of amphioxus in captivity can be achieved. This has practical implications for the cultivation of other amphioxus species, and eventually will greatly promote the utilization of amphioxus as a model system.

  4. Salmon Site Remedial Investigation Report, Appendix C

    International Nuclear Information System (INIS)

    1999-01-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  5. Salmon Site Remedial Investigation Report, Appendix C

    Energy Technology Data Exchange (ETDEWEB)

    US DOE/NV

    1999-09-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  6. Salmon Site Remedial Investigation Report, Exhibit 5

    International Nuclear Information System (INIS)

    1999-01-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  7. Salmon Site Remedial Investigation Report, Main Body

    Energy Technology Data Exchange (ETDEWEB)

    US DOE/NV

    1999-09-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  8. Salmon Site Remedial Investigation Report, Exhibit 5

    Energy Technology Data Exchange (ETDEWEB)

    USDOE/NV

    1999-09-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  9. Salmon Site Remedial Investigation Report, Appendix D

    International Nuclear Information System (INIS)

    1999-01-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  10. Salmon Site Remediation Investigation Report, Appendix A

    International Nuclear Information System (INIS)

    1999-01-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  11. Salmon Site Remedial Investigation Report, Exhibit 2

    Energy Technology Data Exchange (ETDEWEB)

    USDOE NV

    1999-09-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  12. Salmon Site Remedial Investigation Report, Exhibit 2

    International Nuclear Information System (INIS)

    1999-01-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  13. Summary of Temperature Data Collected to Improve Emergence Timing Estimates for Chum and Fall Chinook Salmon in the Lower Columbia River, 1998-2004 Progress Report.

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, E.; Geist, D.; Hanrahan, T.

    2005-10-01

    From 1999 through 2004, Pacific Northwest National Laboratory collected temperature data from within chum and fall Chinook salmon spawning gravels and the overlying river at 21 locations in the Ives Island area approximately 5 km downstream from Bonneville Dam. Sample locations included areas where riverbed temperatures were elevated, potentially influencing alevin development and emergence timing. The study objectives were to (1) collect riverbed and river temperature data each year from the onset of spawning (October) to the end of emergence (June) and (2) provide those data in-season to fisheries management agencies to assist with fall Chinook and chum salmon emergence timing estimates. Three systems were used over the life of the study. The first consisted of temperature sensors deployed inside piezometers that were screened to the riverbed or the river within chum and fall Chinook salmon spawning areas. These sensors required direct access by staff to download data and were difficult to recover during high river discharge. The second system consisted of a similar arrangement but with a wire connecting the thermistor to a data logger attached to a buoy at the water surface. This system allowed for data retrieval at high river discharge but proved relatively unreliable. The third system consisted of temperature sensors installed in piezometers such that real-time data could be downloaded remotely via radio telemetry. After being downloaded, data were posted hourly on the Internet. Several times during the emergence season of each year, temperature data were downloaded manually and provided to management agencies. During 2003 and 2004, the real-time data were made available on the Internet to assist with emergence timing estimates. Examination of temperature data reveals several important patterns. Piezometer sites differ in the direction of vertical flow between surface and subsurface water. Bed temperatures in upwelling areas are more stable during salmon

  14. Investigations of Bull Trout (Salvelinus Confluentus), Steelhead Trout (Oncorhynchus Mykiss), and Spring Chinook Salmon (O. Tshawytscha) Interactions in Southeast Washington Streams. Final Report 1992.

    Energy Technology Data Exchange (ETDEWEB)

    Underwood, Keith D.

    1995-01-01

    The goal of this two year study was to determine if supplementation with hatchery reared steelhead trout (Oncorhynchus mykiss) and spring chinook salmon (O. tshawytscha) negatively impacted wild native bull trout (Salvelinus confluentus) through competitive interactions. Four streams with varying levels of fish supplementation activity were sampled in Southeast Washington. Tasks performed during this study were population density, relative abundance, microhabitat utilization, habitat availability, diet analysis, bull trout spawning ground surveys, radio telemetry of adult bull trout, and growth analysis. Results indicate that bull trout overlapped geographically with the supplemented species in each of the study streams suggesting competition among species was possible. Within a stream, bull trout and the supplemented species utilized dissimilar microhabitats and microhabitat utilization by each species was the same among streams suggesting that there was no shifts in microhabitat utilization among streams. The diet of bull trout and O. mykiss significantly overlapped in each of the study streams. The stream most intensely supplemented contained bull trout with the slowest growth and the non-supplemented stream contained bull trout with the fastest growth. Conversely, the stream most intensely supplemented contain steelhead with the fastest growth and the non-supplemented stream contained steelhead with the slowest growth. Growth indicated that bull trout may have been negatively impacted from supplementation, although other factors may have contributed. At current population levels, and current habitat quantity and quality, no impacts to bull trout as a result of supplementation with hatchery reared steelhead trout and spring chinook salmon were detected. Project limitations and future research recommendations are discussed.

  15. Investigations of bull trout (Salvelinus confluentus), steelhead trout (Oncorhynchus mykiss), and spring chinook salmon (O. tshawytscha) interactions in Southeast Washington streams. Final report 1992

    International Nuclear Information System (INIS)

    Underwood, K.D.; Martin, S.W.; Schuck, M.L.; Scholz, A.T.

    1995-01-01

    The goal of this two year study was to determine if supplementation with hatchery reared steelhead trout (Oncorhynchus mykiss) and spring chinook salmon (O. tshawytscha) negatively impacted wild native bull trout (Salvelinus confluentus) through competitive interactions. Four streams with varying levels of fish supplementation activity were sampled in Southeast Washington. Tasks performed during this study were population density, relative abundance, microhabitat utilization, habitat availability, diet analysis, bull trout spawning ground surveys, radio telemetry of adult bull trout, and growth analysis. Results indicate that bull trout overlapped geographically with the supplemented species in each of the study streams suggesting competition among species was possible. Within a stream, bull trout and the supplemented species utilized dissimilar microhabitats and microhabitat utilization by each species was the same among streams suggesting that there was no shifts in microhabitat utilization among streams. The diet of bull trout and O. mykiss significantly overlapped in each of the study streams. The stream most intensely supplemented contained bull trout with the slowest growth and the non-supplemented stream contained bull trout with the fastest growth. Conversely, the stream most intensely supplemented contain steelhead with the fastest growth and the non-supplemented stream contained steelhead with the slowest growth. Growth indicated that bull trout may have been negatively impacted from supplementation, although other factors may have contributed. At current population levels, and current habitat quantity and quality, no impacts to bull trout as a result of supplementation with hatchery reared steelhead trout and spring chinook salmon were detected. Project limitations and future research recommendations are discussed

  16. Investigations of bull trout (Salvelinus confluentus), steelhead trout (Oncorhynchus mykiss), and spring chinook salmon (O. tshawytscha) interactions in Southeast Washington streams. Final report 1992; FINAL

    International Nuclear Information System (INIS)

    Underwood, K.D.; Martin, S.W.; Schuck, M.L.; Scholz, A.T.

    1995-01-01

    The goal of this two year study was to determine if supplementation with hatchery reared steelhead trout (Oncorhynchus mykiss) and spring chinook salmon (O. tshawytscha) negatively impacted wild native bull trout (Salvelinus confluentus) through competitive interactions. Four streams with varying levels of fish supplementation activity were sampled in Southeast Washington. Tasks performed during this study were population density, relative abundance, microhabitat utilization, habitat availability, diet analysis, bull trout spawning ground surveys, radio telemetry of adult bull trout, and growth analysis. Results indicate that bull trout overlapped geographically with the supplemented species in each of the study streams suggesting competition among species was possible. Within a stream, bull trout and the supplemented species utilized dissimilar microhabitats and microhabitat utilization by each species was the same among streams suggesting that there was no shifts in microhabitat utilization among streams. The diet of bull trout and O. mykiss significantly overlapped in each of the study streams. The stream most intensely supplemented contained bull trout with the slowest growth and the non-supplemented stream contained bull trout with the fastest growth. Conversely, the stream most intensely supplemented contain steelhead with the fastest growth and the non-supplemented stream contained steelhead with the slowest growth. Growth indicated that bull trout may have been negatively impacted from supplementation, although other factors may have contributed. At current population levels, and current habitat quantity and quality, no impacts to bull trout as a result of supplementation with hatchery reared steelhead trout and spring chinook salmon were detected. Project limitations and future research recommendations are discussed

  17. Temporally stable population-specific differences in run timing of one-sea-winter Atlantic salmon returning to a large river system.

    Science.gov (United States)

    Vähä, Juha-Pekka; Erkinaro, Jaakko; Niemelä, Eero; Primmer, Craig R; Saloniemi, Irma; Johansen, Morten; Svenning, Martin; Brørs, Sturla

    2011-01-01

    The understanding of migration patterns can significantly contribute to conservation and management. The spawning migrations of Atlantic salmon (Salmo salar) cover thousands of kilometers from the feeding areas at sea to their natal rivers to reproduce. Migrating salmon are exposed to intensive harvest, but little is known of the population-specific differences in migration behavior. In this study, timing of return migration was investigated among one-sea-winter Atlantic salmon within a river system. By utilizing knowledge of the genetic population structure, population of origin was reliably identified for c. 1500 fish caught in mixed stock fisheries after adopting an approach to minimize the complications arising from potential nonsampled populations. Results demonstrated significant and temporally stable differences among populations as well as between sexes. Generally, female salmon from tributary populations entered fresh water first. Run timing was not however related to in-river migration distance. Rather, one-sea-winter salmon from larger populations and with a higher proportion of multi-sea-winter females arrived later in the season. These findings are a significant step toward a more thorough understanding of the salmon migration behavior and behavioral ecology, providing concrete tools for the management and conservation of the remaining indigenous Atlantic salmon stocks.

  18. Spatio-temporal dynamics of a fish spawning aggregation and its fishery in the Gulf of California.

    Science.gov (United States)

    Erisman, Brad; Aburto-Oropeza, Octavio; Gonzalez-Abraham, Charlotte; Mascareñas-Osorio, Ismael; Moreno-Báez, Marcia; Hastings, Philip A

    2012-01-01

    We engaged in cooperative research with fishers and stakeholders to characterize the fine-scale, spatio-temporal characteristics of spawning behavior in an aggregating marine fish (Cynoscion othonopterus: Sciaenidae) and coincident activities of its commercial fishery in the Upper Gulf of California. Approximately 1.5-1.8 million fish are harvested annually from spawning aggregations of C. othonopterus during 21-25 days of fishing and within an area of 1,149 km(2) of a biosphere reserve. Spawning and fishing are synchronized on a semi-lunar cycle, with peaks in both occurring 5 to 2 days before the new and full moon, and fishing intensity and catch are highest at the spawning grounds within a no-take reserve. Results of this study demonstrate the benefits of combining GPS data loggers, fisheries data, biological surveys, and cooperative research with fishers to produce spatio-temporally explicit information relevant to the science and management of fish spawning aggregations and the spatial planning of marine reserves.

  19. Predicting the Influence of Streamflow on Migration and Spawning of a Threatened Diadromous Fish, the Australian Grayling Prototroctes Maraena

    Science.gov (United States)

    Koster, W. M.; Crook, D. A.; Dawson, D. R.; Gaskill, S.; Morrongiello, J. R.

    2018-03-01

    The development of effective strategies to restore the biological functioning of aquatic ecosystems with altered flow regimes requires a detailed understanding of flow-ecology requirements, which is unfortunately lacking in many cases. By understanding the flow conditions required to initiate critical life history events such as migration and spawning, it is possible to mitigate the threats posed by regulated river flow by providing targeted environmental flow releases from impoundments. In this study, we examined the influence of hydrological variables (e.g., flow magnitude), temporal variables (e.g., day of year) and spatial variables (e.g., longitudinal position of fish) on two key life history events (migration to spawning grounds and spawning activity) for a threatened diadromous fish (Australian grayling Prototroctes maraena) using data collected from 2008 to 2015 in the Bunyip-Tarago river system in Victoria. Our analyses revealed that flow changes act as a cue to downstream migration, but movement responses differed spatially: fish in the upper catchment showed a more specific requirement for rising discharge to initiate migration than fish in the lower catchment. Egg concentrations peaked in May when weekly flows increased relative to the median flow during a given spawning period. This information has recently been incorporated into the development of targeted environmental flows to facilitate migration and spawning by Australian grayling in the Bunyip-Tarago river system and other coastal systems in Victoria.

  20. Research on Captive Broodstock Programs for Pacific Salmon, 2003-2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Berejikian, Barry A.; Athos, Jaime I.; Dittman, Andrew H. (National Marine Fisheries Service)

    2004-07-01

    The success of captive broodstock programs depends on high in-culture survival, appropriate development of the reproductive system, and the behavior and survival of cultured salmon after release, either as adults or juveniles. Continuing captive broodstock research designed to improve technology is being conducted to cover all major life history stages of Pacific salmon. We were able to develop an analytical method for optimizing the detection of spawning events in Chinook salmon using EMG signals. The method developed essentially captured the consistently greater frequency of higher EMG values associated with females cover digging immediately following spawning. However, females implanted with EMG tags retained the majority of their eggs, which significantly reduced their reproductive success compared to non-tagged females. Future work will include increased sample sizes, and modified tagging methods to reduce negative effects on reproductive success. Upper Columbia River sockeye salmon exposed to the odorants PEA, L-threonine, Larginine and L-glutamate were able to learn and remember these odorants as maturing adults up to 2.5 years after exposure. These results suggest that the alevin and smolt stages are both important developmental periods for successful olfactory imprinting. Furthermore, the period of time that fish are exposed to imprinting odors may be important for successful imprinting. Experimental fish exposed to imprinting odors as smolts for six or one weeks successfully imprinted to these odors but imprinting could not be demonstrated in smolts exposed to odors for only one day. A 2-3 C reduction in seawater rearing temperature during the fall and winter prior to final maturation had little effect on reproductive development of spring Chinook salmon. Body size at spawning and total ovary mass were similar between temperature treatments. The percentage of fertilized eggs was significantly higher for females exposed to the ambient temperature compared

  1. Effects of salmon lice infection and salmon lice protection on fjord migrating Atlantic salmon and brown trout post-smolts

    DEFF Research Database (Denmark)

    Sivertsgard, Rolf; Thorstad, Eva B.; Okland, Finn

    2007-01-01

    Effects of artificial salmon lice infection and pharmaceutical salmon lice prophylaxis on survival and rate of progression of Atlantic salmon (n = 72) and brown trout post-smolts (n = 72) during their fjord migration, were studied by telemetry. The infected groups were artificially exposed...... development during the study period. Neither salmon lice infection nor pharmaceutical prophylaxis had any effects on survival and rate of progression of fjord migrating Atlantic salmon post-smolts compared to control fish. Atlantic salmon spent on average only 151.2 h (maximum 207.3 h) in passing the 80 km......, was found in brown trout during the first weeks of their fjord migration. Brown trout will, to a larger extent than Atlantic salmon, stay in the fjord areas when salmon lice infections reach the more pathogenic pre-adult and adult stages. In contrast to Atlantic salmon, they will thereby possess...

  2. Fish research project -- Oregon: Investigations into the early life history of naturally produced spring chinook salmon in the Grande Ronde River Basin. Annual progress report, 1 September 1995--31 August 1996

    International Nuclear Information System (INIS)

    Jonasson, B.C.; Carmichael, R.W.; Keefe, M.

    1997-09-01

    Historically, the Grande Ronde River produced an abundance of salmonids including stocks of spring, summer and fall chinook salmon, sockeye salmon, coho salmon, and summer steelhead. During the past century, numerous factors have caused the reduction of salmon stocks such that only sustainable stocks of spring chinook salmon and summer steelhead remain. The sizes of spring chinook salmon populations in the Grande Ronde River basin also have been declining steadily and are substantially depressed from estimates of historic levels. In addition to a decline in population abundance, a reduction of spring chinook salmon spawning distribution is evident in the Grande Ronde River basin. Numerous factors are thought to contribute to the decline of spring chinook salmon in the Snake River and its tributaries. These factors include passage problems and increased mortality of juvenile and adult migrants at mainstem Columbia and Snake river dams, overharvest, and habitat degradation associated with timber, agricultural, and land development practices. This study was designed to describe aspects of the life history strategies exhibited by spring chinook salmon in the Grande Ronde River basin. During the past year the focus was on rearing and migration patterns of juveniles in the upper Grande Ronde River and Catherine Creek. The study design included three objectives: (1) document the annual in-basin migration patterns for spring chinook salmon juveniles in the upper Grande Ronde River and Catherine Creek, including the abundance of migrants, migration timing and duration; (2) estimate and compare smolt survival indices to mainstem Columbia and Snake river dams for fall and spring migrating spring chinook salmon; and (3) determine summer and winter habitat utilization and preference of juvenile spring chinook salmon in the upper Grande Ronde River and Catherine Creek

  3. Restoration and enhancement of Atlantic salmon populations: what we have learned from North Iberian rivers

    Directory of Open Access Journals (Sweden)

    Horreo J.L.

    2012-01-01

    Full Text Available Found on the southernmost edge of the species’ natural distribution, North Iberian Atlantic salmon populations are extremely vulnerable to environmental change. In the last few decades, associated with global indicators of climate change, these populations have been experiencing a sharp decline. Efforts have been made to address their decline, principally through stocking, supportive breeding and habitat restoration (enabling accessibility to upstream spawning sites. The efficiency of each of these measures has been different. In this study, focused on the river Sella containing one of the largest Spanish populations as a case study, we demonstrate that accessibility and habitat improvement have been the most efficient measures for increasing population size. Supportive breeding accounts for some level of population increase, but generally lower than 10%. Finally, our review suggests that stocking should be discarded as a restoration method because it encompasses threats to natural variation of Atlantic salmon and also the sympatric brown trout.

  4. Research on Captive Broodstock Programs for Pacific Salmon, 2002-2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Berejikian, Barry A. (National Marine Fisheries Service)

    2004-01-01

    The success of captive broodstock programs depends on high in-culture survival, appropriate development of the reproductive system, and the behavior and survival of cultured salmon after release, either as adults or juveniles. Continuing captive broodstock research designed to improve technology is being conducted to cover all major life history stages of Pacific salmon. Current velocity in rearing vessels had little if any effect on reproductive behavior of captively reared steelhead. However, males and females reared in high velocity vessels participated a greater number of spawning events than siblings reared in low velocity tanks. Observations of nesting females and associated males in a natural stream (Hamma Hamma River) were consistent with those observed in a controlled spawning channel. DNA pedigree analyses did not reveal significant differences in the numbers of fry produced by steelhead reared in high and low velocity vessels. To determine the critical period(s) for imprinting for sockeye salmon, juvenile salmon are being exposed to known odorants at key developmental stages. Subsequently they will be tested for development of long-term memories of these odorants. In 2002-2003, the efficacy of EOG analysis for assessing imprinting was demonstrated and will be applied in these and other behavioral and molecular tools in the current work plan. Results of these experiments will be important to determine the critical periods for imprinting for the offspring of captively-reared fish destined for release into natal rivers or lakes. By early August, the oocytes of all of Rapid River Hatchery chinook salmon females returning from the ocean had advanced to the tertiary yolk globule stage; whereas, only some of the captively reared Lemhi River females sampled had advanced to this stage, and the degree of advancement was not dependent on rearing temperature. The mean spawning time of captive Lemhi River females was 3-4 weeks after that of the Rapid River fish

  5. Observations of Acropora spawning in the Mozambique Channel ...

    African Journals Online (AJOL)

    There is little published information about the reproductive biology of corals in the western Indian Ocean region. In particular, information about coral spawning patterns is largely absent from scientific literature. We document scleractinian coral spawning events - 8 species of Acropora - from the Mozambique Channel, ...

  6. Influence of inoculation method and spawn level on biological ...

    African Journals Online (AJOL)

    Abstract. Pleurotus ostreatus, an edible mushroom cultivated worldwide and appreciated due to its exotic taste and nutritional value. Spawning rate and method of spawn application are crucial factors influencing mushroom growth and yield. ... The highest number of fruits (11.33), fruit weight (65.69g), widest pileus (657cm.) ...

  7. Characterising and comparing the spawning habitats of anchovy ...

    African Journals Online (AJOL)

    SARP data showed that anchovy spawning was associated with cool water and moderate wind and current speeds, whereas sardine spawning was related to warmer water and more turbulent and unstable conditions (i.e. high wind speeds and strong currents) than for anchovy. SARP data also showed significant ...

  8. Influence of Inoculation Method and Spawn Level on Biological ...

    African Journals Online (AJOL)

    ADOWIE PERE

    due to its exotic taste and nutritional value. Spawning rate ... biological efficiency (62.57%) when spawn was applied at both ends of the bag while the least was on the .... opening of the bags. The harvesting was done as the mushrooms appeared. Days to substrate colonization and time of primodia initiation were noted.

  9. Salmon Population Summary - Impacts of climate change on Pacific salmon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This work involves 1) synthesizing information from the literature and 2) modeling impacts of climate change on specific aspects of salmon life history and...

  10. Cardiac arrest during gamete release in chum salmon regulated by the parasympathetic nerve system.

    Directory of Open Access Journals (Sweden)

    Yuya Makiguchi

    Full Text Available Cardiac arrest caused by startling stimuli, such as visual and vibration stimuli, has been reported in some animals and could be considered as an extraordinary case of bradycardia and defined as reversible missed heart beats. Variability of the heart rate is established as a balance between an autonomic system, namely cholinergic vagus inhibition, and excitatory adrenergic stimulation of neural and hormonal action in teleost. However, the cardiac arrest and its regulating nervous mechanism remain poorly understood. We show, by using electrocardiogram (ECG data loggers, that cardiac arrest occurs in chum salmon (Oncorhynchus keta at the moment of gamete release for 7.39+/-1.61 s in females and for 5.20+/-0.97 s in males. The increase in heart rate during spawning behavior relative to the background rate during the resting period suggests that cardiac arrest is a characteristic physiological phenomenon of the extraordinarily high heart rate during spawning behavior. The ECG morphological analysis showed a peaked and tall T-wave adjacent to the cardiac arrest, indicating an increase in potassium permeability in cardiac muscle cells, which would function to retard the cardiac action potential. Pharmacological studies showed that the cardiac arrest was abolished by injection of atropine, a muscarinic receptor antagonist, revealing that the cardiac arrest is a reflex response of the parasympathetic nerve system, although injection of sotalol, a beta-adrenergic antagonist, did not affect the cardiac arrest. We conclude that cardiac arrest during gamete release in spawning release in spawning chum salmon is a physiological reflex response controlled by the parasympathetic nervous system. This cardiac arrest represents a response to the gaping behavior that occurs at the moment of gamete release.

  11. Olfactory responses to natal stream water in sockeye salmon by BOLD fMRI.

    Directory of Open Access Journals (Sweden)

    Hiroshi Bandoh

    Full Text Available Many studies have shown that juvenile salmon imprint olfactory memory of natal stream odors during downstream migration, and adults recall this stream-specific odor information to discriminate their natal stream during upstream migration for spawning. The odor information processing of the natal stream in the salmon brain, however, has not been clarified. We applied blood oxygenation level-dependent (BOLD functional magnetic resonance imaging to investigate the odor information processing of the natal stream in the olfactory bulb and telencephalon of lacustrine sockeye salmon (Oncorhynchus nerka. The strong responses to the natal stream water were mainly observed in the lateral area of dorsal telencephalon (Dl, which are homologous to the medial pallium (hippocampus in terrestrial vertebrates. Although the concentration of L-serine (1 mM in the control water was 20,000-times higher than that of total amino acid in the natal stream water (47.5 nM, the BOLD signals resulting from the natal stream water were stronger than those by L-serine in the Dl. We concluded that sockeye salmon could process the odor information of the natal stream by integrating information in the Dl area of the telencephalon.

  12. 1992 Columbia River Salmon Flow Measures Options Analysis/EIS : Appendices.

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    This Options Analysis/Environmental Impact Statement (OA/EIS) identifies, presents effects of, and evaluates the potential options for changing instream flow levels in efforts to increase salmon populations in the lower Columbia and Snake rivers. The potential actions would be implemented during 1992 to benefit juvenile and adult salmon during migration through eight run-of-river reservoirs. The Corps of Engineers (Corps) prepared this document in cooperation with the Bonneville Power Administration and the Bureau of Reclamation. The US Fish and Wildlife Service (FWS) is a participating agency. The text and appendices of the document describe the characteristics of 10 Federal projects and one private water development project in the Columbia River drainage basin. Present and potential operation of these projects and their effects on the salmon that spawn and rear in the Columbia and Snake River System are presented. The life history, status, and response of Pacific salmon to current environmental conditions are described. The document concludes with an evaluation of the potential effects that could result from implementing proposed actions. The conclusions are based on evaluation of existing data, utilization of numerical models, and application of logical inference. This volume contains the appendices.

  13. Spatial distribution of mercury in southeastern Alaskan streams influenced by glaciers, wetlands, and salmon

    International Nuclear Information System (INIS)

    Nagorski, Sonia A.; Engstrom, Daniel R.; Hudson, John P.; Krabbenhoft, David P.; Hood, Eran; DeWild, John F.; Aiken, George R.

    2014-01-01

    Southeastern Alaska is a remote coastal-maritime ecosystem that is experiencing increased deposition of mercury (Hg) as well as rapid glacier loss. Here we present the results of the first reported survey of total and methyl Hg (MeHg) concentrations in regional streams and biota. Overall, streams draining large wetland areas had higher Hg concentrations in water, mayflies, and juvenile salmon than those from glacially-influenced or recently deglaciated watersheds. Filtered MeHg was positively correlated with wetland abundance. Aqueous Hg occurred predominantly in the particulate fraction of glacier streams but in the filtered fraction of wetland-rich streams. Colonization by anadromous salmon in both glacier and wetland-rich streams may be contributing additional marine-derived Hg. The spatial distribution of Hg in the range of streams presented here shows that watersheds are variably, yet fairly predictably, sensitive to atmospheric and marine inputs of Hg. -- Highlights: • We sampled 21 streams in southeastern Alaska for water, sediments, and biota. • Aqueous Hg showed significant relationships with wetlands and DOC. • Biota had higher mercury in wetland-rich streams than in glacier-fed streams. • Spawning salmon appear to contribute methylmercury to stream foodwebs. -- This original survey of mercury concentration and form in southeastern Alaskan streamwater and biota shows substantial spatial variation linked to landscape factors and salmon influence

  14. 1992 Columbia River salmon flow measures Options Analysis/EIS: Appendices

    International Nuclear Information System (INIS)

    1992-01-01

    This Options Analysis/Environmental Impact Statement (OA/EIS) identifies, presents effects of, and evaluates the potential options for changing instream flow levels in efforts to increase salmon populations in the lower Columbia and Snake rivers. The potential actions would be implemented during 1992 to benefit juvenile and adult salmon during migration through eight run-of-river reservoirs. The Corps of Engineers (Corps) prepared this document in cooperation with the Bonneville Power Administration and the Bureau of Reclamation. The US Fish and Wildlife Service (FWS) is a participating agency. The text and appendices of the document describe the characteristics of 10 Federal projects and one private water development project in the Columbia River drainage basin. Present and potential operation of these projects and their effects on the salmon that spawn and rear in the Columbia and Snake River System are presented. The life history, status, and response of Pacific salmon to current environmental conditions are described. The document concludes with an evaluation of the potential effects that could result from implementing proposed actions. The conclusions are based on evaluation of existing data, utilization of numerical models, and application of logical inference. This volume contains the appendices

  15. Atlantic salmon brood stock management and breeding handbook

    Science.gov (United States)

    Kincaid, Harold L.; Stanley, Jon G.

    1989-01-01

    Anadromus runs of Atlantic salmon have been restored to the Connecticut, Merrimack, Pawcatuck, Penobscot, and St. Croix rivers in New England by the stocking of more than 8 million smolts since 1948. Fish-breeding methods have been developed that minimize inbreeding and domestication and enhance natural selection. Methods are available to advance the maturation of brood stock, control the sex of production lots and store gametes. Current hatchery practices emphasize the use of sea-run brood stock trapped upon return to the rivers and a limited number of captive brood stock and rejuvenated kelts. Fish are allowed to mature naturally, after which they are spawned and incubated artificially. Generally, 1-year smolts are produced, and excess fish are stocked as fry in headwater streams. Smolts are stocked during periods of rising water in spring. Self-release pools are planned that enable smolts to choose the emigration time. Culturists keep good records that permit evaluation of the performance of strains and the effects of breeding practices. As Atlantic salmon populations expand, culturists must use sound breeding methods that enhance biotic potential while maintaining genetic diversity and protecting unique gene pools.

  16. Modeling the brain-pituitary-gonad axis in salmon

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jonghan; Hayton, William L.; Schultz, Irv R.

    2006-08-24

    To better understand the complexity of the brain-pituitary-gonad axis (BPG) in fish, we developed a biologically based pharmacodynamic model capable of accurately predicting the normal functioning of the BPG axis in salmon. This first-generation model consisted of a set of 13 equations whose formulation was guided by published values for plasma concentrations of pituitary- (FSH, LH) and ovary- (estradiol, 17a,20b-dihydroxy-4-pregnene-3-one) derived hormones measured in Coho salmon over an annual spawning period. In addition, the model incorporated pertinent features of previously published mammalian models and indirect response pharmacodynamic models. Model-based equations include a description of gonadotropin releasing hormone (GnRH) synthesis and release from the hypothalamus, which is controlled by environmental variables such as photoperiod and water temperature. GnRH stimulated the biosynthesis of mRNA for FSH and LH, which were also influenced by estradiol concentration in plasma. The level of estradiol in the plasma was regulated by the oocytes, which moved along a maturation progression. Estradiol was synthesized at a basal rate and as oocytes matured, stimulation of its biosynthesis occurred. The BPG model can be integrated with toxico-genomic, -proteomic data, allowing linkage between molecular based biomarkers and reproduction in fish.

  17. Using a Genetic mixture model to study Phenotypic traits: Differential fecundity among Yukon river Chinook Salmon

    Science.gov (United States)

    Bromaghin, J.F.; Evenson, D.F.; McLain, T.H.; Flannery, B.G.

    2011-01-01

    Fecundity is a vital population characteristic that is directly linked to the productivity of fish populations. Historic data from Yukon River (Alaska) Chinook salmon Oncorhynchus tshawytscha suggest that length-adjusted fecundity differs among populations within the drainage and either is temporally variable or has declined. Yukon River Chinook salmon have been harvested in large-mesh gill-net fisheries for decades, and a decline in fecundity was considered a potential evolutionary response to size-selective exploitation. The implications for fishery conservation and management led us to further investigate the fecundity of Yukon River Chinook salmon populations. Matched observations of fecundity, length, and genotype were collected from a sample of adult females captured from the multipopulation spawning migration near the mouth of the Yukon River in 2008. These data were modeled by using a new mixture model, which was developed by extending the conditional maximum likelihood mixture model that is commonly used to estimate the composition of multipopulation mixtures based on genetic data. The new model facilitates maximum likelihood estimation of stock-specific fecundity parameters without first using individual assignment to a putative population of origin, thus avoiding potential biases caused by assignment error.The hypothesis that fecundity of Chinook salmon has declined was not supported; this result implies that fecundity exhibits high interannual variability. However, length-adjusted fecundity estimates decreased as migratory distance increased, and fecundity was more strongly dependent on fish size for populations spawning in the middle and upper portions of the drainage. These findings provide insights into potential constraints on reproductive investment imposed by long migrations and warrant consideration in fisheries management and conservation. The new mixture model extends the utility of genetic markers to new applications and can be easily adapted

  18. Steroidogenesis in the testes and seminal vesicles of spawning and non-spawning African catfish, Clarias gariepinus

    NARCIS (Netherlands)

    Schoonen, W.G.E.J.; Granneman, J.C.M.; Lambert, J.G.D.; Oordt, P.G.W.J. van

    1987-01-01

    The in vitro biosynthesis of steroids was studied in testes as well as seminal vesicles of non-spawning pond and spawning feral African catfish, collected during the breeding season. In testes of non-spawners the conversion of [3H]-pregnenolone was directed towards 11-oxygenated androgens and

  19. Effects of sex steroids, sex, and sexual maturity on cortisol production: an in vitro comparison of chinook salmon and rainbow trout interrenals.

    Science.gov (United States)

    McQuillan, H James; Lokman, P Mark; Young, Graham

    2003-08-01

    Sex steroids appear to be responsible for hyperactivation of the hypothalamus-pituitary-interrenal (HPI) axis that occurs in mature semelparous Pacific salmon as a prelude to post-spawning (programmed) death. This study was undertaken to examine the direct effects of sex steroids on interrenal activity of semelparous (chinook salmon) and iteroparous (rainbow trout) salmonids using an in vitro incubation system. In addition, phenotypic sex differences in cortisol production by interrenals of sexually mature (spawning) rainbow trout and chinook salmon were investigated. Interrenal tissue from juvenile and sexually mature chinook salmon and rainbow trout was incubated for 48 h in culture medium containing either no steroid (controls), 1 microM estradiol (E2) or 1 microM 11-ketotestosterone (11-KT). This tissue was then challenged for 3h with either pregnenolone, dibutyryladenosine 3('):5(')-cyclic monophosphate (dbcAMP) or forskolin, or synthetic human adrenocorticotropic hormone (ACTH(1-24)). Sex differences in in vitro interrenal cortisol production were assessed using separate tissue pools challenged with the same agents. Cortisol in media was measured by radioimmunoassay. E2 suppressed the ability of juvenile chinook salmon interrenals to utilize pregnenolone as substrate for cortisol synthesis. In mature female chinook salmon the suppressive effect of E2 was less pronounced, but was observed as a reduced response of interrenals to both pregnenolone and dbcAMP. E2 did not affect ACTH(1-24) stimulated cortisol production. Immature and mature rainbow trout interrenals were both relatively insensitive to E2. 11-KT did not affect cortisol production by juvenile chinook salmon and juvenile or mature rainbow trout, and had only minor effects in male and female spawning chinook salmon. In mature chinook salmon and rainbow trout, the interrenals of females were more responsive to ACTH stimulation and showed a greater utilization of pregnenolone as a substrate than

  20. Snake River Sockeye Salmon Captive Broodstock Program, Research Element : Project Progress Report, 2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hebdon, J. Lance (Jason Lance); Castillo, Jason; Kline, Paul A.

    2002-08-01

    On November 20, 1991, the National Marine Fisheries Service listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. In 1991, the Shoshone-Bannock Tribes and Idaho Department of Fish and Game initiated the Snake River Sockeye Salmon Sawtooth Valley Project to conserve and rebuild populations in Idaho. Restoration efforts are focusing on Redfish, Pettit, and Alturas lakes within the Sawtooth Valley. The first release of hatchery-produced juvenile sockeye salmon from the captive broodstock program occurred in 1994. The first anadromous adult returns from the captive broodstock program were recorded in 1999 when six jacks and one jill were captured at Idaho Department of Fish and Game's Sawtooth Fish Hatchery. In 2000, progeny from the captive broodstock program were released using four strategies: eyed-eggs were placed in Pettit Lake; age-0 presmolts were released to all three lakes in October; age-1 smolts were released to Redfish Lake Creek, and hatchery-produced adult sockeye salmon were released to Redfish and Alturas lakes for volitional spawning in September. Anadromous adult sockeye salmon were released to all three lakes. Total kokanee abundance in Redfish Lake was estimated at 10,268, which was the lowest abundance since 1991. Abundance of kokanee in Alturas Lake was estimated at 125,462, which was one of the highest values recorded since 1991. Abundance of kokanee in Pettit Lake was estimated at 40,599, which is the third highest value recorded since 1991. Upon the recommendation of the Stanley Basin Sockeye Technical Oversight Committee, the National Marine Fisheries Service reopened the kokanee fishery on Redfish Lake in 1995 in an attempt to reduce kokanee numbers. Anglers fished an estimated 3,063 hours and harvested approximately 67 kokanee during the 2000 season. Angler effort and harvest were also monitored on Alturas Lake during 2000. Effort on Alturas Lake was 5,190 hours, and harvest of

  1. Sustainable fisheries management: Pacific salmon

    Science.gov (United States)

    Knudsen, E. Eric; Steward, Cleveland R.; MacDonald, Donald; Williams, Jack E.; Reiser, Dudley W.

    1999-01-01

    What has happened to the salmon resource in the Pacific Northwest? Who is responsible and what can be done to reverse the decline in salmon populations? The responsibly falls on everyone involved - fishermen, resource managers and concerned citizens alike - to take the steps necessary to ensure that salmon populations make a full recovery.This collection of papers examines the state of the salmon fisheries in the Pacific Northwest. They cover existing methods and supply model approaches for alternative solutions. The editors stress the importance of input from and cooperation with all parties involved to create a viable solution. Grass roots education and participation is the key to public support - and ultimately the success - of whatever management solutions are developed.A unique and valuable scientific publication, Sustainable Fisheries Management: Pacific Salmon clearly articulates the current state of the Pacific salmon resource, describes the key features of its management, and provides important guidance on how we can make the transition towards sustainable fisheries. The solutions presented in this book provide the basis of a strategy for sustainable fisheries, requiring society and governmental agencies to establish a shared vision, common policies, and a process for collaborative management.

  2. Behavior and movement of formerly landlocked juvenile coho salmon after release into the free-flowing Cowlitz River, Washington

    Science.gov (United States)

    Kock, Tobias J.; Henning, Julie A.; Liedtke, Theresa L.; Royer, Ida M.; Ekstrom, Brian K.; Rondorf, Dennis W.

    2011-01-01

    Formerly landlocked Coho Salmon (Oncorhynchus kisutch) juveniles (age 2) were monitored following release into the free-flowing Cowlitz River to determine if they remained in the river or resumed seaward migration. Juvenile Coho Salmon were tagged with a radio transmitter (30 fish) or Floy tag (1050 fish) and their behavior was monitored in the lower Cowlitz River. We found that 97% of the radio-tagged fish remained in the Cowlitz River beyond the juvenile outmigration period, and the number of fish dispersing downstream decreased with increasing distance from the release site. None of the tagged fish returned as spawning adults in the 2 y following release. We suspect that fish in our study failed to migrate because they exceeded a threshold in size, age, or physiological status. Tagged fish in our study primarily remained in the Cowlitz River, thus it is possible that these fish presented challenges to juvenile salmon migrating through the system either directly by predation or indirectly by competition for food or habitat. Given these findings, returning formerly landlocked Coho Salmon juveniles to the free-flowing river apparently provided no benefit to the anadromous population. These findings have management implications in locations where landlocked salmon have the potential to interact with anadromous species of concern.

  3. Assessment of potential impacts of major groundwater contaminants to fall chinook salmon (Oncorhynchus tshawytscha) in the Hanford Reach, Columbia River

    International Nuclear Information System (INIS)

    Geist, D.R.; Poston, T.M.; Dauble, D.D.

    1994-10-01

    Past operations of Hanford Site facilities have contaminated the groundwater adjacent to the Hanford Reach of the Columbia River, Washington, with various chemical and radiological constituents. The groundwater is hydraulically connected to the river and contains concentrations of contaminants that sometimes exceed federal and/or state drinking water standards or standards for the protection of aquatic life. For example, concentrations of chromium in shoreline seeps and springs at most 100 Area operable units exceed concentrations found to be toxic to fish. Nitrate and tritium concentrations in shoreline seeps are generally below drinking water standards and concentrations potentially toxic to aquatic life, but nitrate concentrations may be high enough to synergistically interact with and exacerbate chromium toxicity. The Hanford Reach also supports the largest run of fall chinook salmon (Oncorhynchus tshawytscha) in the Columbia River Basin. Numbers of fall chinook salmon returning to the Hanford Reach have increased relative to other mainstem populations during the last 30 years. Groundwater discharge appears to occur near some salmon spawning areas, but contaminants are generally not detectable in surface water samples. The concentration and potential toxicity of contaminants in the interstitial waters of the substrate where fall chinook salmon embryogenesis occurs are presently unknown. New tools are required to characterize the extent of groundwater contaminant discharge to the Hanford Reach and to resolve uncertainties associated with assessment of potential impacts to fall chinook salmon

  4. 78 FR 62616 - Salmon Creek Hydroelectric Company, Salmon Creek Hydroelectric Company, LLC; Notice of Transfer...

    Science.gov (United States)

    2013-10-22

    ... Hydroelectric Company, Salmon Creek Hydroelectric Company, LLC; Notice of Transfer of Exemption 1. By letter filed September 23, 2013, Salmon Creek Hydroelectric Company informed the Commission that they have changed its name to Salmon Creek Hydroelectric Company, LLC for the Salmon Creek Hydroelectric Project...

  5. Optimisation Of Volvariella volvacea Spawn Production For High Mycelia Growth

    International Nuclear Information System (INIS)

    Nie, H.J.; Azhar Mohamad; Joyce, Y.S.M.; Muhamad Najmi Moin

    2016-01-01

    Volvariella volvacea is a tropical mushroom cultivated throughout the world mostly in Asia and Europe for its taste, nutrition, fast growing nature and simple method of cultivation. It is also widely cultivated in Malaysia and known locally as Paddy Straw Mushroom. Growers strive to obtain high quality mushroom spawn to achieve high production. High quality spawn with fast mycelia growth are achieved through strain selection and optimisation of seedling production conditions. This study aims to optimise spawn production through 3 studies along the production main stages. Firstly, comparisons were made between agar media. Mycelia grown on Malt Extract Agar (MEA) covered the agar plates 2 days faster than Potato Dextrose Agar (PDA) grown mycelia. The next stage is of mother grain spawn production by inoculating a bag of grains from mycelia agar plugs. Bags are then sealed with caps. The amount of aeration for grain spawn were studied by using two types of caps. Caps with hole allowed more aeration compared to caps without holes. Study determined bags with more aeration colonised grains 2 days faster than bags with lesser aeration. For the final stage of producing planting spawn, the growth on paddy straw substrate with and without kapok (10 %) were evaluated. Results revealed mycelia fully colonised the substrate bags without kapok 1-2 days faster than substrate bags with kapok. These findings contribute in achieving production of high quality Volvariella volvacea spawn. (author)

  6. Coho Salmon Habitat in a Changing Environment-Green Valley Creek, Graton, California

    Science.gov (United States)

    O'Connor, M. D.; Kobor, J. S.; Sherwood, M. N.

    2013-12-01

    Green Valley Creek (GVC) is a small (101 sq km) aquatic habitat refugium in the Russian River watershed (3,840 sq km) in coastal northern California. Coho salmon (Onchorhynchus kisutch) is endangered per the Federal Endangered Species Act, and GVC is one stream where coho have persisted. Fish surveys in GVC have found high species diversity, growth rates, and over-summer survival. The upper portion of GVC comprises a principal tributary (20 sq km) that provides spawning and rearing habitat for coho. The second principal tributary, Atascadero Creek, is comparable in size, but has few fish. Atascadero Creek and lower GVC have broad, densely vegetated floodplains. A Recovery Plan for the Central Coastal California coho Evolutionarily Significant Unit has been developed by the National Marine Fisheries Service (NMFS), which applies to the Russian River and its tributaries. Cooperative research regarding fish populations and habitat, a captive breeding and release program for native coho salmon, and efforts to plan for and restore habitat are ongoing. These regional efforts are particularly active in GVC, and participants include NMFS, the California Department of Fish and Wildlife, the Gold Ridge Resource Conservation District, the California Coastal Conservancy, the University of California Cooperative Extension, and the National Fish and Wildlife Foundation, among others. Our research focuses on hydrologic, geomorphic and hydrogeologic characteristics of the watershed in relation to aquatic habitat. Natural watershed factors contributing to habitat for coho include proximity to the coastal summer fog belt with cool temperatures, the Wilson Grove Formation aquifer that maintains dry season stream flow, and structural geology favorable for active floodplain morphology. Human impacts include water use and agriculture and rural residential development. Historic human impacts include stream clearing and draining of wetlands and floodplain for agriculture, which likely

  7. Thiamine content of eggs and lengths of coho salmon (Oncorhynchus kisutch) in relation to abundance of alewife (Alosa pseudoharengus) in eastern Lake ontario, 2003 to 2006

    Science.gov (United States)

    Ketola, H.G.; Rinchard, J.; O'Gorman, R.; Begnoche, L.J.; Bishop, D.L.; Greulich, A.W.

    2009-01-01

    Early mortality syndrome in fry of Great Lakes salmonines is linked to reduced levels of thiamine in eggs, which reflects maternal consumption of forage fishes such as alewife (Alosa pseudoharengus) that contain thiaminase, an enzyme that destroys thiamine. We assessed annual variations in abundance and condition of alewives and thiamine status of coho salmon (Oncorhynchus kisutch) in Lake Ontario. We analyzed total thiamine in eggs of 20 coho salmon collected annually between 2003 and 2006 at the Salmon River Hatchery on the Salmon River, New York. Alewife abundance was assessed annually in southern and eastern Lake Ontario with bottom trawls during late April and early May. Mean thiamine concentration in eggs varied annually, with those collected in 2003 (2.5 nmol/g) being significantly higher than those collected in 2004 to 2006 (1.5 to 1.7 nmol/g). Although we did not test survival of fry, if reported threshold levels of thiamine for preventing mortality of Lake Michigan coho salmon fry apply, then many or most Lake Ontario coho salmon produced fry were likely to incur thiamine-deficiency mortality, especially during years 2004 to 2006. Comparison to indices of annual abundance of alewife in Lake Ontario with thiamine concentration in coho salmon eggs failed to show any significant correlations (P > 0.05). However, total length of female spawning coho salmon was positively correlated (P < 0.05) with increasing condition and estimated energy content of adult alewives in the previous spring. These results suggest that growth of coho salmon in Lake Ontario was first limited by energy intake, whereas the amount of thiamine provided by alewives was sufficient for growth (in length) but not for producing thiamine-adequate eggs.

  8. AquAdvantage Salmon Genetically modified organism

    OpenAIRE

    Núñez Saurí, Ester

    2014-01-01

    Póster AquAdvantage Salmon is a genetically modified organism developed by AquBounty Technologies. The objective of this transgenic organism is to increase the growth rate to obtain the same of conventional salmon faster.

  9. Changes in Habitat and Populations of Steelhead Trout, Coho Salmon, and Chinook Salmon in Fish Creek, Oregon; Habitat Improvement, 1983-1987 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Everest, Fred H. (Oregon State University, Pacific Northwest Forest and Range Experiment Station, Corvallis, OR); Hohler, David B.; Cain, Thomas C. (Mount Hood National Forest, Clackamas River Ranger District, Estacada, OR)

    1988-03-01

    Construction and evaluation of salmonid habitat improvements on Fish Creek, a tributary of the upper Clackamas River, began in 1982 as a cooperative venture between the Estacada Ranger District, Mt. Hood National Forest, and the Anadromous Fish Habitat Research Unit of the Pacific Northwest Research Station (PNW), USDA Forest Service. The project was initially conceived as a 5-year effort (1982-1987) to be financed with Forest Service funds. The habitat improvement program and the evaluation of improvements were both expanded in mid-1983 when the Bonneville Power Administration (BPA) entered into an agreement with the Mt. Hood National Forest to cooperatively fund work on Fish Creek. Habitat improvement work in the basin is guided by the Fish Creek Habitat Rehabilitation-Enhancement Framework developed cooperatively by the Estacada Ranger District, the Oregon Department of Fish and Wildlife, and the Pacific Northwest Research Station. The framework examines potential factors limiting production of salmonids in the basin, and the appropriate habitat improvement measures needed to address the limiting factors. Habitat improvement work in the basin has been designed to: (1) improve quantity, quality, and distribution of spawning habitat for coho and spring chinook salmon and steelhead trout, (2) increase low flow rearing habitat for steelhead trout and coho salmon, (3) improve overwintering habitat for coho salmon and steelhead trout, (4) rehabilitate riparian vegetation to improve stream shading to benefit all species, and (5) evaluate improvement projects from a drainage wide perspective. The objectives of the evaluation include: (1) Drainage-wide evaluation and quantification of changes in salmonid spawning and rearing habitat resulting from a variety of habitat improvements. (2) Evaluation and quantification of changes in fish populations and biomass resulting from habitat improvements. (3) Benefit-cost analysis of habitat improvements.

  10. Composition and relative abundance of fish species in the lower White Salmon River, Washington, prior to the removal of Condit Dam

    Science.gov (United States)

    Allen, M. Brady; Connolly, Patrick J.

    2011-01-01

    upriver bright fall Chinook salmon out-migration period.When water levels in the White Salmon River declined in late summer, we electrofished the river margins in 2006–09 along three sites at rkm 1.5, 2.3, and 4.2. Age-0 steelhead were the most abundant fish captured (n=565, 62 percent), followed by age-0 coho salmon (n=222, 24 percent). In autumn, age-0 Chinook salmon were collected while electrofishing (n=40, 4 percent). This suggests that there may be a migration in the autumn as age-0 Chinook salmon or in the spring as age-1 Chinook salmon, since the Chinook salmon that migrate as age-0 fish in the spring departed several months earlier (the typical life history for fall Chinook salmon). The only age-1 salmonids captured while electrofishing were steelhead (n=84, 9 percent). Fish distribution and abundance will likely change when Condit Dam is removed and anadromous fish gain access to their historical spawning and rearing areas in the White Salmon River. These findings should provide a baseline with which to compare juvenile fish species composition and relative abundance after Condit Dam is removed.

  11. Identification of marine-derived lipids in juvenile coho salmon and aquatic insects through fatty acid analysis

    Science.gov (United States)

    Heintz, Ron A.; Wipfli, Mark S.; Hudson, John P.

    2010-01-01

    The energetic benefits enjoyed by consumers in streams with salmon runs depend on how those benefits are accrued. Adult Pacific salmon Oncorhynchus spp. deliver significant amounts of nutrients (i.e., nitrogen and phosphorus) and carbon to streams when they spawn and die; these nutrient additions can have demonstrable effects on primary production in streams. Consumption of carcass tissues or eggs provides for direct energy subsidies to consumers and may have significant effects on their condition. In this study, comparisons of juvenile coho salmon O. kisutch and aquatic insects exposed to terrestrial and marine energy sources demonstrated that direct consumption of marine-derived lipids had a significant effect on the lipid reserves of consumers. Direct consumption of marine-derived tissues was verified through fatty acid analysis. Selected aquatic insects and juvenile coho salmon were reared for 6 weeks in experimental streams supplied with terrestrial or marine energy sources. Chironomid midges, nemourid stoneflies, and juvenile coho salmon exposed to the marine energy source altered their fatty acid compositions by incorporating the long-chain polyunsaturated fatty acids that are characteristic of marine fish. The fatty acid composition of baetid mayflies was unaffected. The direct movement of specific fatty markers indicated that direct consumption of marine-derived tissues led to increased energy reserves (triacylglycerols) in consumers. Similar results were obtained for juvenile coho salmon sampled from natural streams before and after the arrival of adult salmon runs. These data indicate that marine-derived lipids from anadromous fish runs are an important source of reserve lipids for consumers that overwinter in streams.

  12. Coastal oceanographic processes associated with blood cockle (Anadara granosa induce spawning season in Kapar, Selangor, Malaysia

    Directory of Open Access Journals (Sweden)

    Hadzley Harith

    2016-12-01

    Full Text Available Study on coastal processes in Kapar waters was conducted from 2008–2016. The aim of this study is to identify potential blood cockle (Anadara granosa induce spawning ground based on physical intermittency. A total of 132 sampling stations were recorded. A thermal power station situated 2km away is discharging treated warm water (3m MSL which prevents cockle farmers from harvesting due to their maximum of 3m long hand dredge. Thus, this information could be useful for cockle sustainable management plan in near future.

  13. Environmental influences on the spatial ecology and spawning behaviour of an estuarine-resident fish, Macquaria colonorum

    Science.gov (United States)

    Walsh, C. T.; Reinfelds, I. V.; Ives, M. C.; Gray, C. A.; West, R. J.; van der Meulen, D. E.

    2013-02-01

    Estuarine-resident fishes are highly susceptible to the effects of environmental and anthropogenic impacts on their assemblages and habitats. We investigated the distribution, movement and spawning behaviour of estuary perch, Macquaria colonorum, in response to selected environmental variables using an acoustic telemetry array in a large tidal river in south-eastern (SE) Australia. Adult M. colonorum were monitored for up to two years, covering two consecutive spawning periods between September 2007 and 2009. Salinity, water temperature and river flows all had a significant relationship with their estuarine distribution. In particular, large-scale movements were influenced by large freshwater inflow events and the resultant reduction in salinity levels, together with the seasonal cooling and warming trends in water temperatures associated with spawning behaviour. During the winter months, male and female M. colonorum migrated from their upper estuarine home ranges to the lower estuarine spawning grounds in synchrony, with numbers of individual visits by both sexes consistently higher in the 'wetter' winter/spring period of 2008. Location, arrival, departure and occupation time within the spawning grounds were similar between sexes and years. Both resident and migrating M. colonorum exhibited strong diel, and to a lesser extent, tidal behavioural patterns, with fish more likely to be detected at night and during the ebb tides. It is postulated that the effect of environmental fluctuations on the distribution and movement of M. colonorum is influenced by behavioural mechanisms in response to osmoregulatory stress, predator-prey interactions and reproductive activity. The results also demonstrate the importance of accounting for autocorrelation inherent in telemetry data, and for developing management strategies that are more robust to the effect of future climate trends on estuarine fish populations.

  14. Snake River Fall Chinook Salmon life history investigations

    Science.gov (United States)

    Erhardt, John M.; Bickford, Brad; Hemingway, Rulon J.; Rhodes, Tobyn N.; Tiffan, Kenneth F.

    2017-01-01

    Predation by nonnative fishes is one factor that has been implicated in the decline of juvenile salmonids in the Pacific Northwest. Impoundment of much of the Snake and Columbia rivers has altered food webs and created habitat favorable for species such as Smallmouth Bass Micropterus dolomieu. Smallmouth Bass are common throughout the Columbia River basin and have become the most abundant predator in lower Snake River reservoirs (Zimmerman and Parker 1995). This is a concern for Snake River Fall Chinook Salmon Oncorhynchus tshawytscha (hereafter, subyearlings) that may be particularly vulnerable due to their relatively small size and because their main-stem rearing habitats often overlap or are in close proximity to habitats used by Smallmouth Bass (Curet 1993; Tabor et al. 1993). Concern over juvenile salmon predation spawned a number of large-scale studies to quantify its effect in the late 1980s, 1990s, and early 2000s (Poe et al. 1991; Rieman et al. 1991; Vigg et al. 1991; Fritts and Pearsons 2004; Naughton et al. 2004). Smallmouth Bass predation represented 9% of total salmon consumption by predatory fishes in John Day Reservoir, Columbia River, from 1983 through 1986 (Rieman et al. 1991). In transitional habitat between the Hanford Reach of the Columbia River and McNary Reservoir, juvenile salmon (presumably subyearlings) were found in 65% of Smallmouth Bass (>200 mm) stomachs and comprised 59% of the diet by weight (Tabor et al. 1993). Within Lower Granite Reservoir on the Snake River, Naughton et al. (2004) showed that monthly consumption (based on weight) ranged from 5% in the upper reaches of the reservoir to 11% in the forebay. However, studies in the Snake River were conducted soon after Endangered Species Act (ESA) listing of Snake River Fall Chinook Salmon (NMFS 1992). During this time, Fall Chinook Salmon abundance was at an historic low, which may explain why consumption rates were relatively low compared to those from studies conducted in the

  15. Johnson Creek Artificial Propagation and Enhancement Project Operations and Maintenance Program; Brood Year 2000: Johnson Creek Chinook Salmon Supplementation, Biennial Report 2000-2002.

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, Mitch; Gebhards, John; Hill, Robert

    2003-05-01

    The Nez Perce Tribe, through funding provided by the Bonneville Power Administration, has implemented a small scale chinook salmon supplementation program on Johnson Creek, a tributary in the South Fork of the Salmon River, Idaho. The Johnson Creek Artificial Propagation Enhancement project was established to enhance the number of threatened Snake River summer chinook salmon (Oncorhynchus tshawytscha) returning to Johnson Creek through artificial propagation. Adult chinook salmon trapping, broodstock selection, and spawning was first implemented in 1998, did not occur in 1999, and was resumed in 2000. A total of 152 salmon were trapped in Johnson Creek in 2000, of which 73 (25 males, 16 females, and 32 jacks) fish were transported to Idaho Fish and Game=s South Fork Salmon River adult holding and spawning facility for artificial propagation purposes. The remaining 79 (29 males, 16 females, and 24 jacks) fish were released above the weir to spawn naturally. A total of 65,060 green eggs were taken from 16 female salmon and transported to the McCall Fish Hatchery for incubation and rearing. Egg counts indicated an average eye-up rate of 86.0% for 55,971 eyed eggs. Average fecundity for Johnson Creek females was 4,066 eggs per female. Juvenile fish were reared indoors at the McCall Fish Hatchery through November 2001. These fish were transferred to outdoor rearing facilities in December 2001 where they remained until release in March 2002. All of these fish were marked with Coded Wire Tags and Visual Implant Elastomer tags. In addition 9,987 were also PIT tagged. Hand counts provided by marking crews were used to amend the number of juvenile salmon released from the original egg count. A total of 57,392 smolts were released into a temporary acclimation channel in Johnson Creek on March 18, 19, 20, 2002. These fish were held in this facility until a fish screen was removed on March 22, 2002 and the fish were allowed to emigrate.

  16. Source-sink estimates of genetic introgression show influence of hatchery strays on wild chum salmon populations in Prince William Sound, Alaska.

    Directory of Open Access Journals (Sweden)

    James R Jasper

    Full Text Available The extent to which stray, hatchery-reared salmon affect wild populations is much debated. Although experiments show that artificial breeding and culture influence the genetics of hatchery salmon, little is known about the interaction between hatchery and wild salmon in a natural setting. Here, we estimated historical and contemporary genetic population structures of chum salmon (Oncorhynchus keta in Prince William Sound (PWS, Alaska, with 135 single nucleotide polymorphism (SNP markers. Historical population structure was inferred from the analysis of DNA from fish scales, which had been archived since the late 1960's for several populations in PWS. Parallel analyses with microsatellites and a test based on Hardy-Weinberg proportions showed that about 50% of the fish-scale DNA was cross-contaminated with DNA from other fish. These samples were removed from the analysis. We used a novel application of the classical source-sink model to compare SNP allele frequencies in these archived fish-scales (1964-1982 with frequencies in contemporary samples (2008-2010 and found a temporal shift toward hatchery allele frequencies in some wild populations. Other populations showed markedly less introgression, despite moderate amounts of hatchery straying. The extent of introgression may reflect similarities in spawning time and life-history traits between hatchery and wild fish, or the degree that hybrids return to a natal spawning area. The source-sink model is a powerful means of detecting low levels of introgression over several generations.

  17. Mass spawning of corals on a high latitude coral reef

    Science.gov (United States)

    Babcock, R. C.; Wills, B. L.; Simpson, C. J.

    1994-07-01

    Evidence is presented that at least 60% of the 184 species of scleractinian corals found on reefs surrounding the Houtman Abrolhos Islands (Western Australia) participate in a late summer mass spawning. These populations are thus reproductively active, despite most species being at the extreme southern limit of their latitudinal range (28° 29°S). In the present study, coral mass spawning occurred in the same month on both temperate (Houtman-Abrolhos) and tropical (Ningaloo) reefs of Western Australia, despite more than two months difference in the timing of seasonal temperture minima between the two regions. This concurrence in the month of spawning suggests that temperature does not operate as a simple direct proximate cue for seasonal spawning synchrony in these populations. Seasonal variation in photoperiod may provide a similar and more reliable signal in the two regions, and thus might be more likely to synchronize the seasonal reproductive rhythms of these corals. Also there is overlap in the nights of mass spawning on the Houtman Abrolhos and tropical reefs of Western Australia, despite significant differences in tidal phase and amplitude between the two regions. This indicates that tidal cycle does not synchronize with the night(s) of spawning on these reefs. Spawning is more likely to be synchronised by lunar cycles. The co-occurrence of the mass spawning with spring tides in Houtman Abrolhos coral populations may be evidence of a genetic legacy inherited from northern, tropical ancestors. Micro-tidal regimes in the Houtman Abrolhos region may have exerted insufficient selective pressure to counteract this legacy.

  18. Installaton of a fish migration channel for spawning at Itaipu

    International Nuclear Information System (INIS)

    Borghetti, J.R.; Perez Chena, D.; Nogueira, S.V.G.

    1993-01-01

    The objective of installing a fish migration channel for spawning at the Itaipu hydroelectric station on the Parana river between Brazil and Paraguay is to improve fish recovery downstream from the dam. Preliminary data from the first phase has proved the efficiency of an experimental project, with the entry and ascendancy of fish in a migration channel ladder. These data now provide the technical basis for implementation of the complementary spawning channel stage. (author)

  19. The Expression of Leptin, Estrogen Receptors, and Vitellogenin mRNAs in Migrating Female Chum Salmon, : The Effects of Hypo-osmotic Environmental Changes

    Directory of Open Access Journals (Sweden)

    Young Jae Choi

    2014-04-01

    Full Text Available Leptin plays an important role in energy homeostasis and reproductive function in fish, especially in reproduction. Migrating fish, such as salmonoids, are affected by external environmental factors, and salinity changes are a particularly important influence on spawning migrations. The aim of this study was to test whether changes in salinity affect the expression of leptin, estrogen receptors (ERs, and vitellogenin (VTG in chum salmon (Oncorhynchus keta. The expression and activity of leptin, the expression of ERs and VTG, and the levels of estradiol-17β and cortisol increased after the fish were transferred to FW, demonstrating that changes in salinity stimulate the HPG axis in migrating female chum salmon. These findings reveal details about the role of elevated leptin levels and sex steroid hormones in stimulating sexual maturation and reproduction in response to salinity changes in chum salmon.

  20. Snake River sockeye salmon Sawtooth Valley project: 1992 Juvenile and Adult Trapping Program

    International Nuclear Information System (INIS)

    1992-04-01

    Sockeye salmon (Oncorhynchus nerka) runs in the Snake River Basin have severely declined. Redfish Lake near Stanley, Idaho is the only lake in the drainage known to still support a run. In 1989, two adults were observed returning to this lake and in 1990, none returned. In the summer of 1991, only four adults returned. If no action is taken, the Snake River sockeye salmon will probably cease to exist. On November 20, 1991, the National Marine Fisheries Service (NMFS) declared the Snake River sockeye salmon ''endangered'' (effective December 20, 1991), pursuant to the Endangered Species Act (ESA) of 1973. In 1991, in response to a request from the Idaho Department of Fish and Game and the Shoshone-Bannock Tribes, the Bonneville Power Administration (BPA) funded efforts to conserve and begin rebuilding the Snake River sockeye salmon run. The initial efforts were focused on Redfish Lake in the Sawtooth Valley of southcentral Idaho. The 1991 measures involved: trapping some of the juvenile outmigrants (O. nerka) from Redfish Lake and rearing them in the Eagle Fish Health Facility (Idaho Department of Fish and Game) near Boise, Idaho; Upgrading of the Eagle Facility where the outmigrants are being reared; and trapping adult Snake River sockeye salmon returning to Redfish Lake and holding and spawning them at the Sawtooth Hatchery near Stanley, Idaho. This Environmental Assessment (EA) evaluates the potential environmental effects of the proposed actions for 1992. It has been prepared to meet the requirements of the National Environmental Policy Act (NEPA) of 1969 and section 7 of the ESA of 1973

  1. Snake River Sockeye Salmon Habitat and Limnological Research; 2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Andre E.; Taki, Doug (Shoshone-Bannock Tribes, Fort Hall, ID); Griswold, Robert G. (Biolines, Stanley, ID)

    2004-08-01

    In March 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list the Snake River sockeye salmon (Oncorhynchus nerka) as endangered. As a result of that petition the Snake River sockeye salmon was officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991, the Snake River Sockeye Salmon Habitat and Limnological Research Program was implemented (Project Number 91-71, Intergovernmental Contract Number DE-BI79-91bp22548). This project is part of an interagency effort to prevent the extinction of the Redfish Lake stock of O. nerka. The Shoshone-Bannock Tribal goal for this project is two tiered: The immediate goal is to increase the population of Snake River sockeye salmon while preserving the unique genetic characteristics of the Evolutionarily Significant Unit (ESU). The Tribes long term goal is to maintain a viable population that warrants delisting and provides Tribal harvest opportunities. The Bonneville Power Administration (BPA) provides funding for this interagency recovery program through the Northwest Power Planning Council Fish and Wildlife Program (NPPCFWP). Collaborators in the recovery effort include the National Marine Fisheries Service (NMFS), the Idaho Department of Fish and Game (IDFG), the University of Idaho (UI), U.S. Forest Service (USFS), and the Shoshone-Bannock Tribe (SBT). This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the 2002 calendar year. Project objectives include: (1) monitor over-winter survival and emigration of juvenile anadromous O. nerka stocked from the captive rearing program; (2) fertilize Redfish Lake (3) conduct kokanee salmon (non-anadromous O. nerka) population surveys; (4) monitor spawning kokanee escapement and estimate fry recruitment on Fishhook, Alturas Lake, and Stanley Lake creeks; (5) evaluate potential competition and predation between stocked juvenile O. nerka and a

  2. Interspecies variation in the susceptibility of adult Pacific salmon to toxic urban stormwater runoff.

    Science.gov (United States)

    McIntyre, Jenifer K; Lundin, Jessica I; Cameron, James R; Chow, Michelle I; Davis, Jay W; Incardona, John P; Scholz, Nathaniel L

    2018-03-16

    Adult coho salmon (Oncorhynchus kisutch) prematurely die when they return from the ocean to spawn in urban watersheds throughout northwestern North America. The available evidence suggests the annual mortality events are caused by toxic stormwater runoff. The underlying pathophysiology of the urban spawner mortality syndrome is not known, and it is unclear whether closely related species of Pacific salmon are similarly at risk. The present study co-exposed adult coho and chum (O. keta) salmon to runoff from a high traffic volume urban arterial roadway. The spawners were monitored for the familiar symptoms of the mortality syndrome, including surface swimming, loss of orientation, and loss of equilibrium. Moreover, the hematology of both species was profiled by measuring arterial pH, blood gases, lactate, plasma electrolytes, hematocrit, and glucose. Adult coho developed behavioral symptoms within a few hours of exposure to stormwater. Various measured hematological parameters were significantly altered compared to coho controls, indicating a blood acidosis and ionoregulatory disturbance. By contrast, runoff-exposed chum spawners showed essentially no indications of the mortality syndrome, and measured blood hematological parameters were similar to unexposed chum controls. We conclude that contaminant(s) in urban runoff are the likely cause of the disruption of ion balance and pH in coho but not chum salmon. Among the thousands of chemicals in stormwater, future forensic analyses should focus on the gill or cardiovascular system of coho salmon. Because of their distinctive sensitivity to urban runoff, adult coho remain an important vertebrate indicator species for degraded water quality in freshwater habitats under pressure from human population growth and urbanization. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Genet-specific spawning patterns in Acropora palmata

    Science.gov (United States)

    Miller, M. W.; Williams, D. E.; Fisch, J.

    2016-12-01

    The broadcast spawning elkhorn coral, Acropora palmata, requires outcrossing among different genets for effective fertilization. Hence, a low density of genets in parts of its range emphasizes the need for precise synchrony among neighboring genets as sperm concentration dilutes rapidly in open-ocean conditions. We documented the genet-specific nightly occurrence of spawning of A. palmata over 8 yr in a depauperate population in the Florida Keys to better understand this potential reproductive hurdle. The observed population failed to spawn within the predicted monthly window (nights 2-6 after the full moon in August) in three of the 8 yr of observation; negligible spawning was observed in a fourth year. Moreover, genet-specific patterns are evident in that (1) certain genets have significantly greater odds of spawning overall and (2) certain genets predictably spawn on the earlier and others on the later lunar nights within the predicted window. Given the already low genet density in this population, this pattern implies a substantial degree of wasted reproductive effort and supports the hypothesis that depensatory factors are impairing recovery in this species.

  4. Influences of Stocking Salmon Carcass Analogs on Salmonids in Yakima River Tributaries, 2001-2002 Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Pearsons, Todd N.; Johnson, Christopher L. (Washington Department of Fish and Wildlife, Olympia, WA)

    2003-04-01

    The benefits that marine derived nutrients from adult salmon carcasses provide to juvenile salmonids are increasingly being recognized. Current estimates suggest that only 6-7% of marine-derived nitrogen and phosphorus that were historically available to salmonids in the Pacific Northwest are currently available. Food limitation may be a major constraint limiting the restoration of salmonids. A variety of methods have been proposed to offset this nutrient deficit including: allowing greater salmon spawning escapement, stocking hatchery salmon carcasses, and stocking inorganic nutrients. Unfortunately, each of these methods has some ecological or socio-economic shortcoming. We intend to overcome many of these shortcomings by making and evaluating a pathogen free product that simulates a salmon carcass (analog). Abundant sources of marine derived nutrients are available such as fish offal from commercial fishing and salmon carcasses from hatcheries. However, a method for recycling these nutrients into a pathogen free analog that degrades at a similar rate as a natural salmon carcass has never been developed. We endeavored to (1) develop a salmon carcass analog that will increase the food available to salmonids, (2) determine the pathways that salmonids use to acquire food from analogs, and (3) determine the benefits to salmonids and the potential for application to salmonid restoration. We used a before-after-control-impact-paired design in six tributaries of the upper Yakima basin to determine the utility of stocking carcass analogs. Our preliminary results suggest that the introduction of carcass analogs into food-limited streams can be used to restore food pathways previously provided by anadromous salmon. The analogs probably reproduced both of the major food pathways that salmon carcasses produce: direct consumption and food chain enhancement. Trout and salmon fed directly on the carcass analogs during the late summer and presumably benefited from the increased

  5. Canada-USA Salmon Shelf Survival Study, 2007-2008 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Trudel, Marc; Tucker, Strahan; Morris, John

    2009-03-09

    nutrient concentration that year. This suggests nutrients were more effectively by phytoplankton in FY08. In addition, the abundance of lipid-rich northern copepods increased from FY05 to FY08, whereas lipid-poor southern copepods showed the opposite pattern, suggesting that growth conditions were more favorable to juvenile salmon in FY08 than in previous years. However, growth indices for juvenile coho salmon were near the 1998-2008 average, both off the west coast of Vancouver Island and Southeast Alaska, indicating that additional factors beside prey quality affect juvenile salmon growth in the marine environment. Catches of juvenile Chinook, sockeye and chum salmon off the west coast of Vancouver Island in June-July 2008 were the highest on record during summer since 1998, suggesting that early marine survival for the 2008 smolt year was high. Interestingly, the proportion of hatchery fish was high (80-100%) among the juvenile Columbia River Chinook salmon caught off the British Columbia coast during summer, suggest that relatively few wild Chinook salmon are produced in the Columbia River Chinook. In addition, we also recovered two coded-wire tagged juvenile Redfish Lake sockeye salmon in June 2008 off the west coast of British Columbia. As relatively few Redfish Lake sockeye smolts are tagged each year, this also suggests that early marine survival was high for these fish, and may result in a high return in 2009 if they mature at age three, or in 2010 if they mature at age four. To date, our research shows that different populations of Columbia River salmon move to different locations along the coastal zone where they establish their ocean feeding grounds and overwinter. We further show that ocean conditions experienced by juvenile Columbia River salmon vary among regions of the coast, with higher plankton productivity and temperatures off the west coast of Vancouver Island than in Southeast Alaska. Hence, different stocks of juvenile salmon originating from the

  6. Genetic differentiation of spring-spawning and fall-spawning male Atlantic sturgeon in the James River, Virginia.

    Directory of Open Access Journals (Sweden)

    Matthew T Balazik

    Full Text Available Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae populations are currently at severely depleted levels due to historic overfishing, habitat loss, and pollution. The importance of biologically correct stock structure for effective conservation and management efforts is well known. Recent improvements in our understanding of Atlantic sturgeon migrations, movement, and the occurrence of putative dual spawning groups leads to questions regarding the true stock structure of this endangered species. In the James River, VA specifically, captures of spawning Atlantic sturgeon and accompanying telemetry data suggest there are two discrete spawning groups of Atlantic sturgeon. The two putative spawning groups were genetically evaluated using a powerful microsatellite marker suite to determine if they are genetically distinct. Specifically, this study evaluates the genetic structure, characterizes the genetic diversity, estimates effective population size, and measures inbreeding of Atlantic sturgeon in the James River. The results indicate that fall and spring spawning James River Atlantic sturgeon groups are genetically distinct (overall FST = 0.048, F'ST = 0.181 with little admixture between the groups. The observed levels of genetic diversity and effective population sizes along with the lack of detected inbreeding all indicated that the James River has two genetically healthy populations of Atlantic sturgeon. The study also demonstrates that samples from adult Atlantic sturgeon, with proper sample selection criteria, can be informative when creating reference population databases. The presence of two genetically-distinct spawning groups of Atlantic sturgeon within the James River raises concerns about the current genetic assignment used by managers. Other nearby rivers may also have dual spawning groups that either are not accounted for or are pooled in reference databases. Our results represent the second documentation of genetically

  7. Spawning of coral reef invertebrates and a second spawning season for scleractinian corals in the central Red Sea

    KAUST Repository

    Bouwmeester, Jessica

    2016-06-22

    Recent coral spawning observations in the central Red Sea show that most scleractinian species release their gametes in the spring, with a majority of species spawning in April. There is, however, a lack of reproductive data for several other coral species, as well as a general lack of data for other invertebrates. Here, we document the detailed timing of spawning for 13 scleractinian coral species, one sea anemone, and six echinoderms from an inshore reef off the coast of Thuwal, Saudi Arabia, in the spring between April and June 2014. Furthermore, inferred from the presence of mature gametes, we report the month of spawning for three additional coral species in the spring. Seven scleractinian coral species were inferred to release their gametes in a second reproductive season, in the autumn, between September and November. This is the first report of a second spawning season in the Arabian region. Biannual spawning has so far been reported on the Great Barrier Reef, in Western Australia, in Indonesia, in Malaysia, in Palau, in Thailand, in Taiwan, and in Western Samoa. © 2016, The American Microscopical Society, Inc.

  8. Protecting the endangered lake salmon

    Energy Technology Data Exchange (ETDEWEB)

    Soimakallio, H.; Oesch, P. [ed.

    1997-11-01

    In addition to the Ringed Seal, the labyrinthine Saimaa lake system created after the Ice Age also trapped a species of salmon, whose entire life cycle became adapted to fresh water. In order to improve the living conditions of this lake salmon which - like the ringed seal - is today classified as an endangered species, an intensive research programme has been launched. The partners include the Finnish Game and Fisheries Research Institute, fishing and environmental authorities and - in collaboration with UPM-Kymmene Oy and Kuurnan Voima Oy - the IVO subsidiary Pamilo Oy

  9. Protecting the endangered lake salmon

    International Nuclear Information System (INIS)

    Soimakallio, H.; Oesch, P.

    1997-01-01

    In addition to the Ringed Seal, the labyrinthine Saimaa lake system created after the Ice Age also trapped a species of salmon, whose entire life cycle became adapted to fresh water. In order to improve the living conditions of this lake salmon which - like the ringed seal - is today classified as an endangered species, an intensive research programme has been launched. The partners include the Finnish Game and Fisheries Research Institute, fishing and environmental authorities and - in collaboration with UPM-Kymmene Oy and Kuurnan Voima Oy - the IVO subsidiary Pamilo Oy

  10. Re-Introduction of Lower Columbia River Chum Salmon into Duncan Creek, 2001-2002 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hillson, Todd D. (Washington Department of Wildlife, Olympia, WA)

    2002-10-01

    The National Marine Fisheries Service (NMFS) listed Lower Columbia River chum as threatened under the auspices of the Endangered Species Act (ESA) in March of 1999 (64 FR 14508, March 25, 1999). The listing was in response to reduction in abundance from historical levels of more than half a million returning adults to fewer than 10,000 spawners present day (Johnson et al. 1997). Harvest, loss of habitat, changes in flow regimes, riverbed movement and heavy siltation have been largely responsible for the decline in this species in the Columbia River. The timing of seasonal changes in river flow and water temperatures is perhaps the most critical factor in structuring the freshwater life history of chum salmon (Johnson et al. 1997). This is especially true of the population located directly below Bonneville Dam where hydropower operations can block access to spawning sites, dewater redds, strand fry, cause scour or fill of redds and increase sedimentation of spawning gravels. The recovery strategy for Lower Columbia River chum as outlined in the Hatchery Genetic Management Plan (HGMP) for the Grays River project has four main tasks. First, determine if remnant populations of Lower Columbia River chum salmon exist in Lower Columbia River tributaries. Second, if such populations exist, develop stock-specific recovery plans that would involve habitat restoration including the creation of spawning refugias, supplementation if necessary and a habitat and fish monitoring and evaluation plan. If chum have been extirpated from previously utilized streams, develop re-introduction plans that utilize appropriate genetic donor stock(s) of Lower Columbia River chum salmon and integrate habitat improvement and fry-to-adult survival evaluations. Third, reduce the extinction risk to Grays River chum salmon population by randomly capturing adults in the basin for use in a supplementation program and reintroduction of Lower Columbia River chum salmon into the Chinook River basin. The

  11. 50 CFR 226.205 - Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River...

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook...

  12. From salmon to shad: Shifting sources of marine-derived nutrients in the Columbia River Basin

    Science.gov (United States)

    Haskell, Craig A.

    2018-01-01

    Like Pacific salmon (Oncorhynchus spp.), nonnative American shad (Alosa sapidissima) have the potential to convey large quantities of nutrients between the Pacific Ocean and freshwater spawning areas in the Columbia River Basin (CRB). American shad are now the most numerous anadromous fish in the CRB, yet the magnitude of the resulting nutrient flux owing to the shift from salmon to shad is unknown. Nutrient flux models revealed that American shad conveyed over 15,000 kg of nitrogen (N) and 3,000 kg of phosphorus (P) annually to John Day Reservoir, the largest mainstem reservoir in the lower Columbia River. Shad were net importers of N, with juveniles and postspawners exporting just 31% of the N imported by adults. Shad were usually net importers of P, with juveniles and postspawners exporting 46% of the P imported by adults on average. American shad contributed <0.2% of the total annual P load into John Day Reservoir, but during June when most adult shad are migrating into John Day Reservoir, they contributed as much as 2.0% of the P load. Nutrient inputs by American shad were similar to current but far less than historical inputs of Pacific salmon owing to their smaller size. Given the relatively high background P levels and low retention times in lower Columbia River reservoirs, it is unlikely that shad marine-derived nutrients affect nutrient balances or food web productivity through autotrophic pathways. However, a better understanding of shad spawning aggregations in the CRB is needed.

  13. Snake River sockeye salmon habitat and limnological research. Annual report 1994

    International Nuclear Information System (INIS)

    Teuscher, D.; Taki, D.; Wurtsbaugh, W.; Luecke, C.; Budy, P.; Steinhart, G.

    1995-05-01

    Snake River sockeye salmon were listed as endangered in 1991. Since then, the Shoshone-Bannock Tribes (SBT) have been involved in a multi-agency recovery effort. The purpose of this document is to report activities completed in the rearing environments of the Sawtooth Valley Lakes, central Idaho. SBT objectives for 1995 included: continuing population monitoring and spawning habitat surveys; estimating smolt carrying capacity of the lakes, and supervising limnology and barrier modification studies. Hydroacoustic estimates of O. nerka densities in the Sawtooth Valley lakes ranged from 32 to 339 fish/ha. Densities were greatest in Stanley followed by Redfish (217 fish/ha), Pettit (95 fish/ha), and Alturas. Except for Alturas, population abundance estimates were similar to 1993 results. In Alturas Lake, O. nerka abundance declined by approximately 90%. In 1994, about 142,000 kokanee fry recruited to Redfish Lake from Fishhook Creek. O. nerka fry recruitment to Stanley and Alturas lakes was 19,000 and 2,000 fry, respectively. Egg to fry survival was 11%, 13%, and 7% in Fishhook, Alturas and Stanley Lake Creeks. Kokanee spawning in Fishhook Creek was slightly lower than 1993 estimates but similar to the mean escapement since 1991. About 9,200 kokanee entered the creek in 1994 compared to 10,800 in 1993. Escapement for Stanley Lake Creek was only 200, a 68% reduction from 1993. Conversely, O. nerka spawning densities increased to 3,200 in Alturas Lake Creek, up from 200 the previous year

  14. Spawning Economic Development through Enforcement of ...

    African Journals Online (AJOL)

    version of utilitarianism by adding lower and higher types of happiness. In other words, higher pleasures give a greater degree of utility than lower pleasures, as someone who experienced both will forfeit the lower for higher. Morality is not a ground for Bentham's concept of right, rather it is the calculus of pain and pleasure ...

  15. Instream flow characterization of upper Salmon River Basin streams, Central Idaho, 2003

    Science.gov (United States)

    Maret, Terry R.; Hortness, Jon E.; Ott, Douglas S.

    2004-01-01

    Anadromous fish populations in the Columbia River Basin have plummeted in the last 100 years. This severe decline led to Federal listing of chinook salmon (Oncorhynchus tshawytscha) and steelhead trout (Oncorhynchus mykiss) stocks as endangered or threatened under the Endangered Species Act (ESA) in the 1990s. Historically, the upper Salmon River Basin (upstream from the confluence with the Pahsimeroi River) in Idaho provided migration corridors and significant habitat for these ESA-listed species, in addition to the federally listed bull trout (Salvelinus confluentus). Human development has modified the original streamflow conditions in many streams in the upper Salmon River Basin. Summer streamflow modifications, as a result of irrigation practices, have directly affected the quantity and quality of fish habitat and also have affected migration and (or) access to suitable spawning and rearing habitat for these fish. As a result of these ESA listings and Action 149 of the Federal Columbia River Power System Biological Opinion of 2000, the Bureau of Reclamation was tasked to conduct streamflow characterization studies in the upper Salmon River Basin to clearly define habitat requirements for effective species management and habitat restoration. These studies include the collection of habitat and streamflow information for the Physical Habitat Simulation (PHABSIM) model, a widely applied method to determine relations between habitat and discharge requirements for various fish species and life stages. Model results can be used by resource managers to guide habitat restoration efforts in the evaluation of potential fish habitat and passage improvements by increasing streamflow. Instream flow characterization studies were completed on Pole, Fourth of July, Elk, and Valley Creeks during 2003. Continuous streamflow data were collected upstream from all diversions on each stream. In addition, natural summer streamflows were estimated for each study site using regression

  16. Investigations of Bull Trout (Salvelinus Confluentus), Steelhead Trout (Oncorhynchus Mykiss), and Spring Chinook Salmon (O. Tshawytscha) Interactions in Southeast Washington Streams : 1991 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Steven W.

    1992-07-01

    Bull trout (Salvelinus confluentus) are native to many tributaries of the Snake River in southeast Washington. The Washington Department of Wildlife (WDW) and the American Fisheries Society (AFS) have identified bull trout as a species of special concern which means that they may become threatened or endangered by relatively, minor disturbances to their habitat. Steelhead trout/rainbow trout (Oncorhynchus mykiss) and spring chinook salmon (O.tshawytscha) are also native to several tributaries of the Snake river in southeast Washington. These species of migratory fishes are depressed, partially due to the construction of several dams on the lower Snake river. In response to decreased run size, large hatchery program were initiated to produce juvenile steelhead and salmon to supplement repressed tributary stocks, a practice known as supplementation. There is a concern that supplementing streams with artificially high numbers of steelhead and salmon may have an impact on resident bull trout in these streams. Historically, these three species of fish existed together in large numbers, however, the amount of high-quality habitat necessary for reproduction and rearing has been severely reduced in recent years, as compared to historic amounts. The findings of the first year of a two year study aimed at identifying species interactions in southeast Washington streams are presented in this report. Data was collected to assess population dynamics; habitat utilization and preference, feeding habits, fish movement and migration, age, condition, growth, and the spawning requirements of bull trout in each of four streams. A comparison of the indices was then made between the study streams to determine if bull trout differ in the presence of the putative competitor species. Bull trout populations were highest in the Tucannon River (supplemented stream), followed by Mill Creek (unsupplemented stream). Young of the year bull trout utilized riffle and cascade habitat the most in all

  17. Research on Captive Broodstock Programs for Pacific Salmon; Assessment of Captive Broodstock Technologies, Annual Report 2002-2003.

    Energy Technology Data Exchange (ETDEWEB)

    Berejikian, Barry

    2004-01-01

    The success of captive broodstock programs depends on high in-culture survival, appropriate development of the reproductive system, and the behavior and survival of cultured salmon after release, either as adults or juveniles. Continuing captive broodstock research designed to improve technology is being conducted to cover all major life history stages of Pacific salmon. Current velocity in rearing vessels had little if any effect on reproductive behavior of captively reared steelhead. However, males and females reared in high velocity vessels participated a greater number of spawning events than siblings reared in low velocity tanks. Observations of nesting females and associated males in a natural stream (Hamma Hamma River) were consistent with those observed in a controlled spawning channel. DNA pedigree analyses did not reveal significant differences in the numbers of fry produced by steelhead reared in high and low velocity vessels. To determine the critical period(s) for imprinting for sockeye salmon, juvenile salmon are being exposed to known odorants at key developmental stages. Subsequently they will be tested for development of long-term memories of these odorants. In 2002-2003, the efficacy of EOG analysis for assessing imprinting was demonstrated and will be applied in these and other behavioral and molecular tools in the current work plan. Results of these experiments will be important to determine the critical periods for imprinting for the offspring of captively-reared fish destined for release into natal rivers or lakes. By early August, the oocytes of all of Rapid River Hatchery chinook salmon females returning from the ocean had advanced to the tertiary yolk globule stage; whereas, only some of the captively reared Lemhi River females sampled had advanced to this stage, and the degree of advancement was not dependent on rearing temperature. The mean spawning time of captive Lemhi River females was 3-4 weeks after that of the Rapid River fish

  18. Snake River Sockeye Salmon Captive Broodstock Program Research Elements : 2007 Annual Project Progess Report.

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, Mike; Plaster, Kurtis; Redfield, Laura; Heindel, Jeff; Kline, Paul

    2008-12-17

    On November 20, 1991, the National Oceanic Atmospheric Administration listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. In 1991, the Shoshone-Bannock Tribes (SBT) and Idaho Department of Fish and Game (IDFG) initiated the Snake River Sockeye Salmon Captive Broodstock Program to conserve and rebuild populations in Idaho. Restoration efforts are focused on Redfish, Pettit, and Alturas lakes within the Sawtooth Valley. The first release of hatchery-produced adults occurred in 1993. The first release of juvenile sockeye salmon from the captive broodstock program occurred in 1994. In 1999, the first anadromous adult returns from the captive broodstock program were recorded when six jacks and one jill were captured at the IDFG Sawtooth Fish Hatchery. In 2007, progeny from the captive broodstock program were released using four strategies: (1) eyed-eggs were planted in Pettit Lake in November; (2) age-0 presmolts were released to Alturas, Pettit, and Redfish lakes in October; (3) age-1 smolts were released into Redfish Lake Creek and the upper Salmon River in May; and (4) hatchery-produced adult sockeye salmon were released to Redfish Lake for volitional spawning in September. Oncorhynchus nerka population monitoring was conducted on Redfish, Alturas, and Pettit lakes using a midwater trawl in September 2007. Population abundances were estimated at 73,702 fish for Redfish Lake, 124,073 fish for Alturas Lake, and 14,746 fish for Pettit Lake. Angler surveys were conducted from May 26 through August 7, 2007 on Redfish Lake to estimate kokanee harvest. On Redfish Lake, we interviewed 102 anglers and estimated that 56 kokanee were harvested. The calculated kokanee catch rate was 0.03 fish/hour for each kokanee kept. The juvenile out-migrant trap on Redfish Lake Creek was operated from April 14 to June 13, 2007. We estimated that 5,280 natural origin and 14,256 hatchery origin sockeye salmon smolts out-migrated from

  19. Development of Rations for the Enhanced Survival of Salmon, 1983-1984 Progress (Annual) Report.

    Energy Technology Data Exchange (ETDEWEB)

    Crawford, David L.

    1985-04-01

    Hydroelectric development coupled with numerous other encroachments on the supply and quality of water has reduced the natural habitat for the spawning and rearing of salmon in the Columbia river system. Artificial production in hatcheries has become a critical link in the restoration of natural stocks of salmon. Released hatchery salmon must survive predation, be able to acquire sustainable nutrients under natural conditions, possess the vitality to surmount man-made impediments to seaward migration and adapt to a sea water environment. Survival of hatchery salmonids is dependent upon a number of factors. Time of release, natural food abundance, fish size and the health and/or quality of smolts all play synergistic roles. The nutritional and physical characteristics of ration regimes for hatchery fish plays a major role in determining the effectiveness of hatchery production and the health and/or quality of smolts.Ration regimes containing high quality components in uniform and fine-free pellet forms produce efficient growth response and minimize loss of nutrients maintaining the quality of hatchery water supply. Under such feed regimes, fish are less susceptible to disease and more uniform and desirable fish sizes can be achieved at release time. High quality smolts would help to optimize out-migration survival and successful adaptation to salt water.

  20. Parallel signatures of selection in temporally isolated lineages of pink salmon.

    Science.gov (United States)

    Seeb, L W; Waples, R K; Limborg, M T; Warheit, K I; Pascal, C E; Seeb, J E

    2014-05-01

    Studying the effect of similar environments on diverse genetic backgrounds has long been a goal of evolutionary biologists with studies typically relying on experimental approaches. Pink salmon, a highly abundant and widely ranging salmonid, provide a naturally occurring opportunity to study the effects of similar environments on divergent genetic backgrounds due to a strict two-year semelparous life history. The species is composed of two reproductively isolated lineages with overlapping ranges that share the same spawning and rearing environments in alternate years. We used restriction-site-associated DNA (RAD) sequencing to discover and genotype approximately 8000 SNP loci in three population pairs of even- and odd-year pink salmon along a latitudinal gradient in North America. We found greater differentiation within the odd-year than within the even-year lineage and greater differentiation in the southern pair from Puget Sound than in the northern Alaskan population pairs. We identified 15 SNPs reflecting signatures of parallel selection using both a differentiation-based method (BAYESCAN) and an environmental correlation method (BAYENV). These SNPs represent genomic regions that may be particularly informative in understanding adaptive evolution in pink salmon and exploring how differing genetic backgrounds within a species respond to selection from the same natural environment. © 2014 John Wiley & Sons Ltd.

  1. Biodiveristy and Stability of Aboriginal Salmon Fisheries in the Fraser River Watershed

    Science.gov (United States)

    Nesbitt, H. K.; Moore, J.

    2015-12-01

    Natural watersheds are hierarchical networks that may confer stability to ecosystem functions through integration of upstream biodiversity, whereby upstream asset diversification stabilizes the aggregate downstream through the portfolio effect. Here we show that riverine structure and its associated diversity confer stability of salmon catch and lengthened fishing seasons for Aboriginal fisheries on the Fraser River (1370km) in BC, Canada, the second longest dam-free salmon migration route in North America. In Canada, Aboriginal people have rights to fish for food, social, and ceremonial (FSC) purposes. FSC fisheries are located throughout the Fraser watershed and have access to varying levels of salmon diversity based on their location. For instance, fisheries at the mouth of the river have access to all of the salmon that spawn throughout the entire watershed, thus integrating across the complete diversity profile of the entire river. In contrast, fisheries in the headwaters have access to fewer salmon species and populations and thus fish from a much less diverse portfolio. These spatial gradients of diversity within watersheds provide a natural contrast for quantifying the effects of different types of diversity on interannual resource stability and seasonal availability. We acquired weekly and yearly catch totals from 1983 to 2012 (30 years) for Chinook, chum, coho, pink, and sockeye salmon for 21 FSC fishing sites throughout the Fraser River watershed from Fisheries and Oceans Canada. We examined how both population- and species-level diversity affects catch stability and season length at each site by quantifying year-to-year variability and within-year season length respectively. Salmon species diversity made fisheries up to 28% more stable in their catch than predicted with 3.7 more weeks to fish on average. Fisheries with access to high population diversity had up to 3.8 times more stable catch and 3 times longer seasons than less diverse fisheries. We

  2. Abundance, stock origin, and length of marked and unmarked juvenile Chinook salmon in the surface waters of greater Puget Sound

    Science.gov (United States)

    Rice, C.A.; Greene, C.M.; Moran, P.; Teel, D.J.; Kuligowski, D.R.; Reisenbichler, R.R.; Beamer, E.M.; Karr, J.R.; Fresh, K.L.

    2011-01-01

    This study focuses on the use by juvenile Chinook salmon Oncorhynchus tshawytscha of the rarely studied neritic environment (surface waters overlaying the sublittoral zone) in greater Puget Sound. Juvenile Chinook salmon inhabit the sound from their late estuarine residence and early marine transition to their first year at sea. We measured the density, origin, and size of marked (known hatchery) and unmarked (majority naturally spawned) juveniles by means of monthly surface trawls at six river mouth estuaries in Puget Sound and the areas in between. Juvenile Chinook salmon were present in all months sampled (April-November). Unmarked fish in the northern portion of the study area showed broader seasonal distributions of density than did either marked fish in all areas or unmarked fish in the central and southern portions of the sound. Despite these temporal differences, the densities of marked fish appeared to drive most of the total density estimates across space and time. Genetic analysis and coded wire tag data provided us with documented individuals from at least 16 source populations and indicated that movement patterns and apparent residence time were, in part, a function of natal location and time passed since the release of these fish from hatcheries. Unmarked fish tended to be smaller than marked fish and had broader length frequency distributions. The lengths of unmarked fish were negatively related to the density of both marked and unmarked Chinook salmon, but those of marked fish were not. These results indicate more extensive use of estuarine environments by wild than by hatchery juvenile Chinook salmon as well as differential use (e.g., rearing and migration) of various geographic regions of greater Puget Sound by juvenile Chinook salmon in general. In addition, the results for hatchery-generated timing, density, and length differences have implications for the biological interactions between hatchery and wild fish throughout Puget Sound. ?? American

  3. Salmon carcasses increase stream productivity more than inorganic fertilizer pellets: A test on multiple trophic levels in streamside experimental channels

    Science.gov (United States)

    Wipfli, Mark S.; Hudson, John P.; Caouette, John P.; Mitchell, N.L.; Lessard, Joanna L.; Heintz, Ron A.; Chaloner, D.T.

    2010-01-01

    Inorganic nutrient amendments to streams are viewed as possible restoration strategies for re-establishing nutrients and stream productivity throughout the western coast of North America, where salmon runs and associated marine-derived nutrient subsidies have declined. In a mesocosm experiment, we examined the short-term (6 weeks) comparative effects of artificial nutrient pellets and salmon carcasses, alone (low and high amounts) and in combination, on stream food webs. Response variables included dissolved nutrient concentrations, biofilm ash-free dry mass (AFDM) and chlorophyll-alevels, macroinvertebrate density, growth and body condition of juvenile coho salmon Oncorhynchus kisutch, and whole-body lipid content of invertebrates and juvenile coho salmon. Most of the response variables were significantly influenced by carcass treatment; the only response variable significantly influenced by fertilizer pellet treatment was soluble reactive phosphorus (SRP) concentration. Ammonium-nitrogen concentration was the only response variable affected by both (low and high) levels of carcass treatment; all others showed no significant response to the two carcass treatment levels. Significant treatment × time interactions were observed for all responses except nitrate; for most responses, significant treatment effects were detected at certain time periods and not others. For example, significantly higher SRP concentrations were recorded earlier in the experiment, whereas significant fish responses were observed later. These results provide evidence that inorganic nutrient additions do not have the same ecological effects in streams as do salmon carcasses, potentially because inorganic nutrient additions lack carbon-based biochemicals and macromolecules that are sequestered directly or indirectly by consumers. Salmon carcasses, preferably deposited naturally during spawning migrations, appear to be far superior to inorganic nutrient amendments for sustaining and restoring

  4. Spawning Coordination of Mates in a Shell Brooding Cichlid

    Directory of Open Access Journals (Sweden)

    Dolores Schütz

    2012-01-01

    Full Text Available Aim. External fertilisation requires synchronisation of gamete release between the two sexes. Adequate synchronisation is essential in aquatic media because sperm is very short-lived in water. In the cichlid Lamprologus callipterus, fertilisation of the eggs takes place inside an empty snail shell, where females stay inside the shell and males have to ejaculate into the shell opening. This spawning pattern makes the coordination of gamete release difficult. Methods. This study examined the synchronisation of males and females during egg laying. Results. The results showed that the male initiates each spawning sequence and that sperm release and egg laying are very well synchronised. 68% of all sperm releases occurred at exactly the same time when the female laid an egg, and 99% of ejaculations occurred within ±5 seconds from egg deposition. On average 95 eggs are laid one by one with intervals of several minutes between subsequent eggs, leading to a total spawning duration in excess of six hours. Conclusions. We discuss this exceptional spawning pattern and how it might reflect a conflict between the sexes, with males attempting to induce egg laying and females extending the egg laying period to raise the chance for parasitic males to participate in spawning.

  5. How stock of origin affects performance of individuals across a meta-ecosystem: an example from sockeye salmon.

    Science.gov (United States)

    Griffiths, Jennifer R; Schindler, Daniel E; Seeb, Lisa W

    2013-01-01

    Connectivity among diverse habitats can buffer populations from adverse environmental conditions, influence the functioning of meta-ecosystems, and ultimately affect the reliability of ecosystem services. This stabilizing effect on populations is proposed to derive from complementarity in growth and survival conditions experienced by individuals in the different habitats that comprise meta-ecosystems. Here we use the fine scale differentiation of salmon populations between diverse lake habitats to assess how rearing habitat and stock of origin affect the body condition of juvenile sockeye salmon. We use genetic markers (single nucleotide polymorphisms) to assign individuals of unknown origin to stock group and in turn characterize ecologically relevant attributes across habitats and stocks. Our analyses show that the body condition of juvenile salmon is related to the productivity of alternative habitats across the watershed, irrespective of their stock of origin. Emigrants and residents with genetic origins in the high productivity lake were also differentiated by their body condition, poor and high respectively. These emigrants represented a substantial proportion of juvenile sockeye salmon rearing in the lower productivity lake habitat. Despite emigrants originating from the more productive lake, they did not differ in body condition from the individuals spawned in the lower productivity, recipient habitat. Genetic tools allowed us to assess the performance of different stocks groups across the diverse habitats comprising their meta-ecosystem. The ability to characterize the ecological consequences of meta-ecosystem connectivity can help develop strategies to protect and restore ecosystems and the services they provide to humans.

  6. Single nucleotide polymorphisms unravel hierarchical divergence and signatures of selection among Alaskan sockeye salmon (Oncorhynchus nerka populations

    Directory of Open Access Journals (Sweden)

    Habicht Christopher

    2011-02-01

    Full Text Available Abstract Background Disentangling the roles of geography and ecology driving population divergence and distinguishing adaptive from neutral evolution at the molecular level have been common goals among evolutionary and conservation biologists. Using single nucleotide polymorphism (SNP multilocus genotypes for 31 sockeye salmon (Oncorhynchus nerka populations from the Kvichak River, Alaska, we assessed the relative roles of geography (discrete boundaries or continuous distance and ecology (spawning habitat and timing driving genetic divergence in this species at varying spatial scales within the drainage. We also evaluated two outlier detection methods to characterize candidate SNPs responding to environmental selection, emphasizing which mechanism(s may maintain the genetic variation of outlier loci. Results For the entire drainage, Mantel tests suggested a greater role of geographic distance on population divergence than differences in spawn timing when each variable was correlated with pairwise genetic distances. Clustering and hierarchical analyses of molecular variance indicated that the largest genetic differentiation occurred between populations from distinct lakes or subdrainages. Within one population-rich lake, however, Mantel tests suggested a greater role of spawn timing than geographic distance on population divergence when each variable was correlated with pairwise genetic distances. Variable spawn timing among populations was linked to specific spawning habitats as revealed by principal coordinate analyses. We additionally identified two outlier SNPs located in the major histocompatibility complex (MHC class II that appeared robust to violations of demographic assumptions from an initial pool of eight candidates for selection. Conclusions First, our results suggest that geography and ecology have influenced genetic divergence between Alaskan sockeye salmon populations in a hierarchical manner depending on the spatial scale. Second

  7. An assessment of oil-spill effects on pink salmon populations following the Exxon Valdez oil spill. Part 2: Adults and escapement

    International Nuclear Information System (INIS)

    Maki, A.W.; Brannon, E.J.; Gilbertson, L.G.; Moulton, L.L.; Skalski, J.R.

    1995-01-01

    This paper presents results of a field program designed to monitor the status of wildstock pink salmon populations in Prince William Sound following the Exxon Valdez oil spill. Field counts of spawning salmon were conducted each year from 1989 through 1992 to test for spill effects o the distribution nd abundance of pink salmon adults spawning in selected streams in the southwestern portion of Prince William Sound, including streams from the most heavily oiled areas. Counts of whole-stream and intertidal escapement density were statistically compared for 40 study streams in 1989 and for a subset of those streams in successive years. Measurements of residual hydrocarbons were made from stream-bed sediments to test for correlations with spawning behavior. Adult pink salmon in the postspill years of 1990 and 1991, progeny of the year classes considered most vulnerable to the oil spill, returned in high numbers, with the wildstock spawners exceeding their parent year returns. In 1989, adult returns reflected the relatively weak run for that year with a mean spawner density of 0.68 fish/m 2 in reference streams and 0.69 fish/m 2 in oiled streams. In 1990, mean escapement density for reference streams was 1.40 fish/m 2 and 1.55 fish/m 2 for oiled streams, indicating the strongest run of the four study years. Trends in polycyclic aromatic hydrocarbon (PAH) concentrations for the majority of oiled streams show a general decline from 1989 to background levels by 1990. 45 refs., 14 figs., 5 tabs

  8. Increased susceptibility to infectious salmon anemia virus (ISAv) in Lepeophtheirus salmonis – infected Atlantic salmon

    Science.gov (United States)

    The salmon louse and infectious salmon anemia virus (ISAv) are the two most significant pathogens of concern to the Atlantic salmon (Salmo salar) aquaculture industry. However, the interactions between sea lice and ISAv, as well as the impact of a prior sea lice infection on the susceptibility of th...

  9. Barriers impede upstream spawning migration of flathead chub

    Science.gov (United States)

    Walters, David M.; Zuellig, Robert E.; Crockett, Harry J.; Bruce, James F.; Lukacs, Paul M.; Fitzpatrick, Ryan M.

    2014-01-01

    Many native cyprinids are declining throughout the North American Great Plains. Some of these species require long reaches of contiguous, flowing riverine habitat for drifting eggs or larvae to develop, and their declining populations have been attributed to habitat fragmentation or barriers (e.g., dams, dewatered channels, and reservoirs) that restrict fish movement. Upstream dispersal is also needed to maintain populations of species with passively drifting eggs or larvae, and prior researchers have suggested that these fishes migrate upstream to spawn. To test this hypothesis, we conducted a mark–recapture study of Flathead Chub Platygobio gracilis within a 91-km reach of continuous riverine habitat in Fountain Creek, Colorado. We measured CPUE, spawning readiness (percent of Flathead Chub expressing milt), and fish movement relative to a channel-spanning dam. Multiple lines of evidence indicate that Flathead Chub migrate upstream to spawn during summer. The CPUE was much higher at the base of the dam than at downstream sites; the seasonal increases in CPUE at the dam closely tracked seasonal increases in spawning readiness, and marked fish moved upstream as far as 33 km during the spawning run. The upstream migration was effectively blocked by the dam. The CPUE of Flathead Chub was much lower upstream of the OHDD than at downstream sites, and <0.2% of fish marked at the dam were recaptured upstream. This study provides the first direct evidence of spawning migration for Flathead Chub and supports the general hypothesis that barriers limit adult dispersal of these and other plains fishes.

  10. Differences in Reproductive Behavior between Spawning and Non-Spawning Zebrafish Pairs and the Effects of 17α-Ethinylestradiol (EE2

    Directory of Open Access Journals (Sweden)

    Per G. Henriksen

    2016-09-01

    Full Text Available Reproductive success manifested by spawning and fertilization, in most fish, depends partly on an appropriate courtship behavior by both sexes. The zebrafish reproductive behavior can be resolved in some of its constituent elements by a computerized vision system and described in unbiased quantitative terms. Pairs of adult male and female zebrafish were monitored with automatic video tracking at 16 Hz for 45 min in a tank with a spawning area in one corner. Subsequently, spawning, if any, was registered and the swimming behavior and mutual interactions of the two fish were quantified. Further, temporal and frequency distributions of average velocity and turning rate were produced. It is demonstrated that the courtship behavior in spawning pairs differs markedly from non-spawning pairs with differences in both male and female behavior. EE2 (17α-ethinylestradiol, a contraceptive hormone found in aquatic environments, has only a slight effect on these behavior differences between spawning and non-spawning pairs.

  11. Contribution of larval growth rate vairability to the recruitment of the Bay of Málaga anchovy (SW Mediterranean during 2000-2001 spawning seasons

    Directory of Open Access Journals (Sweden)

    Alberto García

    2003-12-01

    Full Text Available Daily growth rates were estimated from larval anchovy (Engraulis encrasicolus sampled in their main nursery grounds off the Bay of Málaga (SW Mediterranean during the 2000 and 2001 spawning seasons. Significantly higher growth rates were observed in the 2001 larval population, representing a 20% increase through the larval size classes analysed. The decimated SW Mediterranean anchovy population experienced a successful anchovy recruitment during this year estimated at 13,000 tons for the Bay of Málaga by the acoustic evaluation of small pelagic resources. The size distribution of the recruited anchovy juveniles during 2000 and 2001 showed an increase of approximately 2 cm. Their corresponding anchovy spawning seasonality agrees with the estimates from the growth model fits of each year. Data on the environmental background for the two years sampled are provided by a historical quarterly monitoring project. Zooplankton showed a two-fold significant increase during July 2001, coastwise as well as offshore. No significant changes in surface temperature were observed between years. Instead of the usual summer spawning peak, anchovy peak spawning shifted towards early spring during the 2001 spawning season. The study provides evidence from field data on the relationships of larval growth variability and recruitment.

  12. Instantaneous 3D Continental-Shelf Scale Imaging of Oceanic Fish by Multi-Spectral Resonance Sensing Reveals Group Behavior during Spawning Migration

    Directory of Open Access Journals (Sweden)

    Dong Hoon Yi

    2018-01-01

    Full Text Available The migration of extensive social groups towards specific spawning grounds in vast and diverse ocean environments is an integral part of the regular spawning process of many oceanic fish species. Oceanic fish in such migrations typically seek locations with environmental parameters that maximize the probability of successful spawning and egg/larval survival. The 3D spatio-temporal dynamics of these behavioral processes are largely unknown due to technical difficulties in sensing the ocean environment over wide areas. Here, we use ocean acoustic waveguide remote sensing (OAWRS to instantaneously image immense herring groups over continental-shelf-scale areas at the Georges Bank spawning ground. Via multi-spectral OAWRS measurements, we capture a shift in swimbladder resonance peak correlated with the herring groups’ up-slope spawning migration, enabling 3D spatial behavioral dynamics to be instantaneously inferred over thousands of square kilometers. We show that herring groups maintain near-bottom vertical distributions with negative buoyancy throughout the migration. We find a spatial correlation greater than 0.9 between the average herring group depth and corresponding seafloor depth for migratory paths along the bathymetric gradient. This is consistent with herring groups maintaining near-seafloor paths to both search for optimal spawning conditions and reduce the risk of predator attacks during the migration to shallower waters where near-surface predators are more dangerous. This analysis shows that multi-spectral resonance sensing with OAWRS can be used as an effective tool to instantaneously image and continuously monitor the behavioral dynamics of swimbladder-bearing fish group behavior in three spatial dimensions over continental-shelf scales.

  13. Microphytoplankton variations during coral spawning at Los Roques, Southern Caribbean

    Directory of Open Access Journals (Sweden)

    Francoise Cavada-Blanco

    2016-03-01

    Full Text Available Phytoplankton drives primary productivity in marine pelagic systems. This is also true for the oligotrophic waters in coral reefs, where natural and anthropogenic sources of nutrients can alter pelagic trophic webs. In this study, microphytoplankton assemblages were characterized for the first time in relation to expected coral spawning dates in the Caribbean. A hierarchical experimental design was used to examine these assemblages in Los Roques archipelago, Venezuela, at various temporal and spatial scales for spawning events in both 2007 and 2008. At four reefs, superficial water samples were taken daily for 9 days after the full moon of August, including days before, during and after the expected days of coral spawning. Microphytoplankton assemblages comprised 100 microalgae taxa at up to 50 cells per mL (mean ± 8 SD and showed temporal and spatial variations related to the coral spawning only in 2007. However, chlorophyll a concentrations increased during and after the spawning events in both years, and this was better matched with analyses of higher taxonomical groups (diatoms, cyanophytes and dinoflagellates, that also varied in relation to spawning times in 2007 and 2008, but asynchronously among reefs. Heterotrophic and mixotrophic dinoflagellates increased in abundance, correlating with a decrease of the diatom Cerataulina pelagica and an increase of the diatom Rhizosolenia imbricata. These variations occurred during and after the coral spawning event for some reefs in 2007. For the first time, a fresh-water cyanobacteria species of Anabaena was ephemerally found (only 3 days in the archipelago, at reefs closest to human settlements. Variability among reefs in relation to spawning times indicated that reef-specific processes such as water residence time, re-mineralization rates, and benthic-pelagic coupling can be relevant to the observed patterns. These results suggest an important role of microheterotrophic grazers in re

  14. A study of the life history of brazilian sardine, Sardinella brasiliensis: II. spawning in 1970 and 1971

    Directory of Open Access Journals (Sweden)

    Yasunobu Matsuura

    1975-01-01

    Full Text Available Distribution and abundance of eggs of Sardinella brasiliensis (=S. aurita, are presented for the years 1970 and 1971 and compared with that of the previous year (1969. The spawning size of three spawning seasons was calculated using Tanaka's method. Incubation time of sardine eggs was estimated using the method of Ahlstrom. During three spawning seasons a considerable change in the relative spawning size was observed. The spawning season (during spring and summer in the southern hemisphere of 1970-71 was poor when compared with those of 1969-70 and 1971-72. A slight change in the average diameter of eggs in different spawning seasons was also observed. The relation between oceanographie conditions and spawning size was analysed. It is suggested that the warm water covering the spawning ground during the 1970-71 spawning season may have caused an unsuccessful spawning in this year.O presente trabalho apresenta a distribuição e abundância de ovos de sardinha verdadeira, Sardinella brasiliensis (=S. aurita, na costa sul do Brasil nos anos de 1970 e 1971. Um dos principais objetivos do estudo quantitativo de ovos e larvas de peixes é estimar o tamanho do estoque, através da abundância de ovos desovados. Com essa finalidade, a computação da abundância de ovos de sardinha verdadeira foi feita usando o método apresentado por Tanaka (1955. O tempo de incubação dos ovos de sardinha foi estimado com base no método da Ahlstrom (1943. A quantidade de ovos desovados variou durante os tres anos (1969 a 1971. Foi feita uma comparação entre a abundância total de ovos desovados e a freqüência de ocorrência de ovos nas estações da região estudada. Os índices de abundância mostram que a desova na época de 1970-71 foi muito fraca, comparada com as de 1969-70 e de 1971-72. Para esclarecer a relação entre a variação anual de tamanho da desova e a condição ambiental, foi analisada a temperatura e salinidade da água na area de desova. Os

  15. Variability of spawning time (lunar day) in Acropora versus merulinid corals: a 7-yr record of in situ coral spawning in Taiwan

    Science.gov (United States)

    Lin, Che-Hung; Nozawa, Yoko

    2017-12-01

    Despite the global accumulation of coral spawning records over the past three decades, information on inter-annual variation in spawning time is still insufficient, resulting in difficulty in predicting coral spawning time. Here, we present new information on in situ spawning times of scleractinian corals at Lyudao, Taiwan, covering their inter-annual variations over a 7-yr period (2010-2016). Spawning of 42 species from 16 genera in eight families was recorded. The majority were hermaphroditic spawners (38 of 42 species), and their spawning occurred 2-4 h after sunset on 1-11 d after the full moon (AFM), mostly in April and May. There were two distinct patterns in the two dominant taxa, the genus Acropora (14 species) and the family Merulinidae (18 species in eight genera). The annual spawning of Acropora corals mostly occurred on a single night in May with high inter-annual variation of spawning (lunar) days between 1 and 11 d AFM. In contrast, the annual spawning of merulinid corals commonly occurred over 2-3 consecutive nights in two consecutive months, April and May, with the specific range of spawning days around the last quarter moon (between 5 and 8 d AFM). The distinct spawning patterns of these taxa were also documented at Okinawa and Kochi, Japan, where similar long-term monitoring of in situ coral spawning has been conducted. This variability in spawning days implies different regulatory mechanisms of synchronous spawning where Acropora corals might be more sensitive to exogenous environmental factors (hourglass mechanism), compared to merulinid corals, which may rely more on endogenous biological rhythms (oscillator mechanism).

  16. Analysis of the association between spawning time QTL markers and the biannual spawning behavior in rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Nelson Colihueque

    2010-01-01

    Full Text Available The rainbow trout is a salmonid fish that occasionally exhibits broodstocks with biannual spawning behavior, a phenomenon known as a double annual reproductive cycle (DARC. Spawning time quantitative trait loci (SPT-QTLs affect the time of the year that female rainbow trout spawn and may influence expression of the DARC trait. In this study, microsatellite markers linked and unlinked to SPT-QTLs were genotyped to investigate the underlying genetics of this trait. SPT-QTLs influenced the DARC trait since in two case-control comparisons three linked markers (OmyFGT12TUF, One3ASC and One19ASC had significant levels of allelic frequency differentiation and marker-character association. Furthermore, alleles of One3ASC and One19ASC had significantly higher frequencies in populations that carried the DARC trait.

  17. Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2004 Smolt Acclimation and Adult Return Report.

    Energy Technology Data Exchange (ETDEWEB)

    Zollman, Richard L.; Eschler, Russell; Sealey, Shawn [Nez Perce Tribe

    2009-03-31

    The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the eighth season (1997-2004) of adult Chinook salmon broodstock collection in the Lostine River and the sixth season (1999-2004) of acclimation of resulting Lostine River progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1) capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progency for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies. In 2004

  18. Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2006 Smolt Acclimation and Adult Return Report.

    Energy Technology Data Exchange (ETDEWEB)

    Zollman, Richard L.; Eschler, Russell; Sealey, Shawn [Nez Perce Tribe

    2009-03-31

    The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the tenth season (1997-2006) of adult Chinook salmon broodstock collection in the Lostine River and the eighth season (1999-2006) of acclimation of resulting Lostine River progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1) capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progeny for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies In 2006

  19. A Bayesian spawning habitat suitability model for American shad in southeastern United States rivers

    Science.gov (United States)

    Hightower, Joseph E.; Harris, Julianne E.; Raabe, Joshua K.; Brownell, Prescott; Drew, C. Ashton

    2012-01-01

    Habitat suitability index models for American shad Alosa sapidissima were developed by Stier and Crance in 1985. These models, which were based on a combination of published information and expert opinion, are often used to make decisions about hydropower dam operations and fish passage. The purpose of this study was to develop updated habitat suitability index models for spawning American shad in the southeastern United States, building on the many field and laboratory studies completed since 1985. We surveyed biologists who had knowledge about American shad spawning grounds, assembled a panel of experts to discuss important habitat variables, and used raw data from published and unpublished studies to develop new habitat suitability curves. The updated curves are based on resource selection functions, which can model habitat selectivity based on use and availability of particular habitats. Using field data collected in eight rivers from Virginia to Florida (Mattaponi, Pamunkey, Roanoke, Tar, Neuse, Cape Fear, Pee Dee, St. Johns), we obtained new curves for temperature, current velocity, and depth that were generally similar to the original models. Our new suitability function for substrate was also similar to the original pattern, except that sand (optimal in the original model) has a very low estimated suitability. The Bayesian approach that we used to develop habitat suitability curves provides an objective framework for updating the model as new studies are completed and for testing the model's applicability in other parts of the species' range.

  20. Evaluation of Fall Chinook and Chum Salmon below Bonneville, The Dalles, John Day and McNary Dams; 1998-1999 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    van der Naald, Wayne; Clark, Roy; Spellman, Bryant

    1999-12-01

    This report describes work conducted by the Oregon Department of Fish and Wildlife (ODFW) and the Washington Department of Fish and Wildlife (WDFW) from 1 October 1998 to 30 September 1999. The work is part of studies to evaluate spawning of fall chinook salmon (Oncorhynchus tshawytscha) and chum salmon (O. keta) below the four lowermost Columbia River dams under the Bonneville Power Administration's Project 99-003. The purpose of this project is twofold: (1) Document the existence of fall chinook and chum populations spawning below Bonneville Dam (river mile (RM) 145), The Dalles Dam (RM 192), John Day Dam (RM 216), and McNary Dam (RM 292) (Figure 1) and estimate the size of these populations; and (2) Profile stocks for important population characteristics; including spawning time, genetic make-up, emergence timing, migration size and timing, and juvenile to adult survival rates. Specific tasks conducted by ODFW and WDFW during this period were: (1) Documentation of fall chinook and chum spawning below Bonneville, The Dalles, John Day and McNary dams using on-water observations; (2) Collection of biological data to profile stocks in areas described in Task 1; (3) Determination of spawning population estimates and age composition, average size at return, and sex ratios in order to profile stocks in areas described in Task 1; (4) Collection of data to determine stock origin of adult salmon found in areas described in Task 1; (5) Determination of possible stock origins of adult salmon found in areas described in Task 1 using tag rates based on coded-wire tag recoveries and genetic baseline analysis; (6) Determination of emergence timing and hatching rate of juvenile fall chinook and chum below Bonneville Dam; (7) Determination of migration time and size for juvenile fall chinook and chum rearing in the area described in Task 6; (8) Investigation of feasibility of determining stock composition of juvenile fall chinook and chum rearing in the area described in

  1. Use of Dual Frequency Identification Sonar to Determine Adult Chinook Salmon (Oncorhynchus tshawytscha) Escapement in the Secesh River, Idaho ; Annual Report, January 2008 – December 2008.

    Energy Technology Data Exchange (ETDEWEB)

    Kucera, Paul A. [Nez Perce Tribe Department of Fisheries Resources Management

    2009-06-26

    Chinook salmon in the Snake River basin were listed as threatened under the Endangered Species Act in 1992 (NMFS 1992). The Secesh River represents the only stream in the Snake River basin where natural origin (wild) salmon escapement monitoring occurs at the population level, absent a supplementation program. As such the Secesh River has been identified as a long term salmon escapement and productivity monitoring site by the Nez Perce Tribe Department of Fisheries Resources Management. Salmon managers will use this data for effective population management and evaluation of the effect of conservation actions on a natural origin salmon population. The Secesh River also acts as a reference stream for supplementation program comparison. Dual frequency identification sonar (DIDSON) was used to determine adult spring and summer Chinook salmon escapement in the Secesh River in 2008. DIDSON technology was selected because it provided a non-invasive method for escapement monitoring that avoided listed species trapping and handling incidental mortality, and fish impedance related concerns. The DIDSON monitoring site was operated continuously from June 13 to September 14. The first salmon passage was observed on July 3. DIDSON site total estimated salmon escapement, natural and hatchery fish, was 888 fish {+-} 65 fish (95% confidence interval). Coefficient of variation associated with the escapement estimate was 3.7%. The DIDSON unit was operational 98.1% of the salmon migration period. Adult salmon migration timing in the Secesh River occurred over 74 days from July 3 to September 14, with 5,262 total fish passages observed. The spawning migration had 10%, median, and 90% passage dates of July 8, July 16, and August 12, respectively. The maximum number of net upstream migrating salmon was above the DIDSON monitoring site on August 27. Validation monitoring of DIDSON target counts with underwater optical cameras occurred for species identification. A total of 860 optical

  2. notes of spawning behaviour of barbel clarias gariepinus burchell in ...

    African Journals Online (AJOL)

    was observed in the Savory dam at the Fisheries Research Centre, Mazoe, Rhodesia. ... From observations at Savory dam this time is much shorter. .... spawning, as large numbers of dead and unfertilized eggs were found in cracks in the clay bottom of the dam. It is probable that eggs and small fry are preyed upon by other ...

  3. Induced spawning of Liza ramada using three different protocols of ...

    African Journals Online (AJOL)

    The second strategy was applied with two injections; the priming dose (3500 IU HCG per fish). Then, the resolving dose (200 µg/kg LHRH-a) was given after 24 h later. The three successful spawning attempts occurred within 3 days when the female received an extra dose of LHRH-a 100 µg/kg (3rd injection) from the ...

  4. Early development of artificially spawned southern mullet, Liza ...

    African Journals Online (AJOL)

    The embryonic development of artificially spawned southern mullet, Liza richardsonii, eggs and the development of the larvae to 46 days are described and illustrated using drawings and photographs. The floating eggs hatched in sea water at 18–24°C after 46–60 h. Newly stripped eggs usually had more than one oil ...

  5. Characterising and comparing the spawning habitats of anchovy ...

    African Journals Online (AJOL)

    The spawning habitats of anchovy Engraulis encrasicolus and sardine Sardinops sagax in the southern Benguela upwelling ecosystem were characterised by comparing their egg abundances with environmental variables measured concomitantly during two different survey programmes: the South African Sardine and ...

  6. Spawning habitat in the spined loach, Cobitis taenia (Cypriniformes: Cobitidae)

    Czech Academy of Sciences Publication Activity Database

    Bohlen, Jörg

    2003-01-01

    Roč. 50, č. 1 (2003), s. 98-101 ISSN 1341-8998 R&D Projects: GA ČR GA206/00/0668 Institutional research plan: CEZ:AV0Z5045916 Keywords : cobitis taenia * spawning substrate * habitat preference Subject RIV: ED - Physiology Impact factor: 0.575, year: 2003

  7. Spatial and Temporal Distribution of Reef Fish Spawning ...

    African Journals Online (AJOL)

    The spatial patterns among fish families were attributed to a combination of differences in species abundance and distribution as well as variation in fishing effort. Spawning periodicity reported by fishers indicated that for snappers and rabbitfishes, the most activity occurred across a protracted period of October to April/May, ...

  8. Fishery benefits from exploiting spawning aggregations not solely ...

    African Journals Online (AJOL)

    The vulnerability of spawning aggregations to exploitation varies among fisheries as a result of differences in the population-density changes associated with this behaviour. However, vulnerability to fishing is also influenced by technology, environmental factors, and fish and fisher behaviours. Focusing on a fishery for the ...

  9. Spawning and development of Lesueurigobius sanzoi ofT northern ...

    African Journals Online (AJOL)

    S.-Afr. Tydskr. Dierk. 1989,24(2). Spawning and development of Lesueurigobius sanzoi ofT northern Namibia. M. P. Olivar. Instituto de Ciencias del Mar, Paseo Nacional sin 08003, Barcelona Spain. Received 22 August 1988; accepted 28 November 1988. The presence of the gobiid Lesueurigobius sanzoi in the Benguela ...

  10. Spawning migration of Labeobarbus species to some tributary rivers ...

    African Journals Online (AJOL)

    Spawning migration of Labeobarbus species was studied from August to December 2013 in some tributary rivers (Qimon, Guanta, Shini, and Chibirna) of Lake Tana. Fish specimens and physico-chemical parameters were measured bimonthly in August and September but monthly from October to December. Adult fish ...

  11. Effects of light dynamics on coral spawning synchrony.

    Science.gov (United States)

    Boch, Charles A; Ananthasubramaniam, Bharath; Sweeney, Alison M; Doyle, Francis J; Morse, Daniel E

    2011-06-01

    Synchrony of spawning in many hermatypic corals, typically a few nights after the full moon, is putatively dependent on solar and lunar light cycles in conjunction with other possible cues such as tides and temperature. We analyze here the contributions of separate components of light dynamics, because the effects of twilight and lunar skylight on coral spawning synchrony have previously been conflated and the alternative hypothesis that these components have differential contributions as proximate cues has not been tested. Moonlight-dependent changes in spectra during twilight, rates of decreasing twilight intensities, and changes in lunar photoperiod were experimentally decoupled using programmed light-emitting diodes and compared for their separate effects on spawning synchrony in Acropora humilis. Effects on synchrony under the control of synthetic lunar cues were greatest in response to changes in lunar photoperiod; changes in light intensities and spectra had lesser influence. No significant differences among treatment responses were found at the circa-diel time scale. We conclude that spawning synchrony on a particular lunar night and specific time of night is a threshold response to differential periods of darkness after twilight that is primarily influenced by lunar photoperiod and secondarily by discrete optical components of early nocturnal illumination.

  12. Spatial and Temporal Distribution of Reef Fish Spawning ...

    African Journals Online (AJOL)

    over-exploitation (Olsen & LaPlace, 1979; Sadovy et al., 1994). It is primarily the coral reef fishes that form transient aggregations that are prioritised for conservation (Colin et al., 2003; Domeier et al., 2002), mainly due to the fact that they may comprise a major proportion of the total spawning stock biomass and constitute ...

  13. Coral mass spawning predicted by rapid seasonal rise in ocean temperature

    KAUST Repository

    Keith, Sally A.

    2016-05-11

    Coral spawning times have been linked to multiple environmental factors; however, to what extent these factors act as generalized cues across multiple species and large spatial scales is unknown. We used a unique dataset of coral spawning from 34 reefs in the Indian and Pacific Oceans to test if month of spawning and peak spawning month in assemblages of Acropora spp. can be predicted by sea surface temperature (SST), photosynthetically available radiation, wind speed, current speed, rainfall or sunset time. Contrary to the classic view that high mean SST initiates coral spawning, we found rapid increases in SST to be the best predictor in both cases (month of spawning: R2 = 0.73, peak: R2 = 0.62). Our findings suggest that a rapid increase in SST provides the dominant proximate cue for coral mass spawning over large geographical scales. We hypothesize that coral spawning is ultimately timed to ensure optimal fertilization success.

  14. An Assessment of the Status of Captive Broodstock Technology of Pacific Salmon, 1995 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Flagg, Thomas A.; Mahnaken, Conrad V.W.; Hard, Jeffrey J.

    1995-06-01

    This report provides guidance for the refinement and use of captive broodstock technology for Pacific salmon (Oncorhynchus spp.) by bringing together information on the husbandry techniques, genetic risks, physiology, nutrition, and pathology affecting captive broodstocks. Captive broodstock rearing of Pacific salmon is an evolving technology, as yet without well defined standards. At present, we regard captive rearing of Pacific salmon as problematic: high mortality rates and low egg viability were common in the programs we reviewed for this report. One of the most important elements in fish husbandry is the culture environment itself. Many captive broodstock programs for Pacific salmon have reared fish from smolt-to-adult in seawater net-pens, and most have shown success in providing gametes for recovery efforts. However, some programs have lost entire brood years to diseases that transmitted rapidly in this medium. Current programs for endangered species of Pacific salmon rear most fish full-term to maturity in fresh well-water, since ground water is low in pathogens and thus helps ensure survival to adulthood. Our review suggested that captive rearing of fish in either freshwater, well-water, or filtered and sterilized seawater supplied to land-based tanks should produce higher survival than culture in seawater net-pens.

  15. Snake River Sockeye Salmon Captive Broodstock Program; Research Element, 2003 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Willard, Catherine; Plaster, Kurtis; Castillo, Jason (Idaho Department of Fish and Game, Boise, ID)

    2005-01-01

    On November 20, 1991, the National Oceanic Atmospheric Administration listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. In 1991, the Shoshone-Bannock Tribes (SBT) and Idaho Department of Fish and Game (IDFG) initiated the Snake River Sockeye Salmon Captive Broodstock Program to conserve and rebuild populations in Idaho. Restoration efforts are focused on Redfish, Pettit, and Alturas lakes within the Sawtooth Valley. The first release of hatchery-produced adults occurred in 1993. The first release of juvenile sockeye salmon from the captive broodstock program occurred in 1994. In 1999, the first anadromous adult returns from the captive broodstock program were recorded when six jacks and one jill were captured at the IDFG Sawtooth Fish Hatchery. In 2003, progeny from the captive broodstock program were released using three strategies: eyed-eggs were planted in Pettit and Alturas lakes in November and December, age-0 presmolts were released to Alturas, Pettit, and Redfish lakes in October, and hatchery-produced adult sockeye salmon were released to Redfish Lake for volitional spawning in September. Oncorhynchus nerka population monitoring was conducted on Redfish, Alturas, and Pettit lakes using a midwater trawl in September 2003. Age-0 through age-4 O. nerka were captured in Redfish Lake, and population abundance was estimated at 81,727 fish. Age-0 through age-3 O. nerka were captured in Alturas Lake, and population abundance was estimated at 46,234 fish. Age-0 through age-3 O. nerka were captured in Pettit Lake, and population abundance was estimated at 11,961 fish. Angler surveys were conducted from May 25 through August 7, 2003 on Redfish Lake to estimate kokanee harvest. On Redfish Lake, we interviewed 179 anglers and estimated that 424 kokanee were harvested. The calculated kokanee catch rate was 0.09 fish/hour. The juvenile out-migrant trap on Redfish Lake Creek was operated from April 15 to May 29

  16. Stream food web response to a salmon carcass analogue addition in two central Idaho, U.S.A. streams

    Science.gov (United States)

    KOHLER, ANDRE E; RUGENSKI, AMANDA; TAKI, DOUG

    2008-01-01

    suggest that SCA addition successfully increased periphyton and macroinvertebrate biomass with no detectable response in streamwater nutrient concentrations. Correspondingly, no change in nutrient limitation status was detected based on dissolved inorganic nitrogen to soluble reactive phosphorus ratios (DIN/SRP) and nutrient-diffusing substrata experiments. Salmon carcass analogues appear to increase freshwater productivity. Salmon carcass analogues represent a pathogen-free nutrient enhancement tool that mimics natural trophic transfer pathways, can be manufactured using recycled fish products, and is easily transported; however, salmon carcass analogues should not be viewed as a replacement for naturally spawning salmon and the important ecological processes they provide.

  17. Ecological effects of re-introduction of salmonid spawning gravel in lowland Danish streams

    DEFF Research Database (Denmark)

    Pedersen, Morten Lauge; Kristensen, Esben; Kronvang, Brian

    2009-01-01

    During the past centuries natural spawning gravel was removed during the regulation of many streams in the Northern Hemisphere and wild fish stocks subsequently suffered due to this severe habitat degradation. To improve spawning conditions, projects involving reintroduction of spawning gravel ha...

  18. Proficiency test for paracitides in salmon muscle

    NARCIS (Netherlands)

    Elbers, I.J.W.

    2012-01-01

    The aim of this proficiency study was to give laboratories the possibility to evaluate or demonstrate their competence for the analysis of parasiticides in salmon muscle. This study also provided an evaluation of the methods applied for the quantitative analysis of parasiticides in salmon muscle.

  19. Re-Introduction of Lower Columbia River Chum Salmon into Duncan Creek, 2003-2004 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Hillson, Todd D. (Washington Department of Fish and Wildlife, Olympia, WA)

    2004-09-01

    Currently, two methods of reintroduction are being simultaneously evaluated at Duncan Creek. Recolonization is occurring by introducing adult chum salmon from the Lower Gorge (LG) population into Duncan Creek and allowing them to naturally reproduce. The supplementation strategy required adults to be collected and artificially spawned, incubated, reared, and released at the mouth of Duncan Creek. All eggs from the artificial crossings at Washougal Hatchery were incubated and the fry reared to release size at the hatchery. The Duncan Creek chum salmon project was very successful in 2003-04, providing knowledge and experience that will improve program execution in future years. The gear used to collect adult brood stock was changed from tangle nets to beach seines. This increased efficiency and the speed at which adults could be processed in the field, and most likely reduced stress on the adults handled. Certain weaknesses exposed in past seasons still exist and new ones were exposed (e.g. inadequate incubation and rearing space at Washougal Hatchery for any large salvage operation and having to move the rearing troughs outside the raceway in 2004). Egg-to-fry survival rates of 64% and 58% showed that the channels are functioning at the upper end of what can be expected from them. Possibly the most important event this season was the ability to strontium mark and release all naturally-produced fry from the spawning channels. Channel and floodplain modifications reduced the likelihood that floods will damage the channels and negatively impact survival rates.

  20. Instream flow characterization of upper Salmon River basin streams, central Idaho, 2004

    Science.gov (United States)

    Maret, Terry R.; Hortness, Jon E.; Ott, Douglas S.

    2005-01-01

    Anadromous fish populations in the Columbia River Basin have plummeted in the last 100 years. This severe decline led to Federal listing of Chinook salmon (Oncorhynchus tshawytscha) and steelhead trout (Oncorhynchus mykiss) stocks as endangered or threatened under the Endangered Species Act (ESA) in the 1990s. Historically, the upper Salmon River Basin (upstream of the confluence with the Pahsimeroi River) in Idaho provided migration corridors and significant habitat for these ESA-listed species, in addition to the ESA-listed bull trout (Salvelinus confluentus). Human development has modified the original streamflow conditions in many streams in the upper Salmon River Basin. Summer streamflow modifications resulting from irrigation practices, have directly affected quantity and quality of fish habitat and also have affected migration and (or) access to suitable spawning and rearing habitat for these fish. As a result of these ESA listings and Action 149 of the Federal Columbia River Power System Biological Opinion of 2000, the Bureau of Reclamation was tasked to conduct streamflow characterization studies in the upper Salmon River Basin to clearly define habitat requirements for effective species management and habitat restoration. These studies include collection of habitat and streamflow information for the Physical Habitat Simulation System model, a widely applied method to determine relations between habitat and discharge requirements for various fish species and life stages. Model results can be used by resource managers to guide habitat restoration efforts by evaluating potential fish habitat and passage improvements by increasing streamflow. In 2004, instream flow characterization studies were completed on Salmon River and Beaver, Pole, Champion, Iron, Thompson, and Squaw Creeks. Continuous streamflow data were recorded upstream of all diversions on Salmon River and Pole, Iron, Thompson, and Squaw Creeks. In addition, natural summer streamflows were

  1. Return Spawning/Rearing Habitat to Anadromous/Resident Fish within the Fishing Creek to Legendary Bear Creek Analysis Area Watersheds; 2002-2003 Final Report.

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Jr., Emmit E. (Nez Perce Tribe, Department of Fisheries Resource Management, Lapwai, ID)

    2004-03-01

    This project is a critical component of currently on-going watershed restoration effort in the Lochsa River Drainage, including the Fishing (Squaw) Creek to Legendary Bear (Papoose) Creek Watersheds Analysis Area. In addition, funding for this project allowed expansion of the project into Pete King Creek and Cabin Creek. The goal of this project is working towards the re-establishment of healthy self-sustaining populations of key fisheries species (spring Chinook salmon, steelhead, bull trout, and westslope cutthroat trout) through returning historic habitat in all life stages (spawning, rearing, migration, and over-wintering). This was accomplished by replacing fish barrier road crossing culverts with structures that pass fish and accommodate site conditions.

  2. Estimating the proportion of river and sea spawning whitefish in catches from the brackish Gulf of Bothnia (Baltic Sea by gill raker counting, genotyping and otolith chemistry analysis

    Directory of Open Access Journals (Sweden)

    Henry Hägerstrand

    2015-11-01

    Full Text Available European whitefish (Coregonus lavaretus is a commercially and recreationally important species in the Gulf of Bothnia (Figure 1, where the salinity of the surface water increases from ~2 ‰ to ~6 ‰ in the north-south (~725 km direction. Two sympatric ecotypes with similar outer features occur: stationary sea spawning whitefish and migrating anadromous river spawning whitefish (Lehtonen 1981. The two types mix in sea away from breeding locations and off breeding time. River spawning whitefish can undertake long feeding and spawning migrations, e.g. between the north and the south of the gulf. The river spawning whitefish abundantly occur at feeding grounds in the south where they stay for years, until maturing. Mainly due to anthropogenic destruction of the spawning rivers, the river spawning whitefish has diminished during last decades and is presently listed among endangered species (Helcom 2013. A reliable assessment of the two ecotypes and their subpopulations is a prerequisite for taking effective actions for stock preservation. In order to compare methods for whitefish ecotype identification we undertook genotyping, otolith chemistry analysis and gill raker counting on river and sea spawning whitefish populations. Materials and methods. Whitefish to undergo spawning was sampled from rivers along the Finnish west coast (river spawners and at sea from known spawning sites close to the southern feeding grounds at the Åland Islands and the Archipelago Sea (sea spawners (Himberg et al. 2015, Figure 1. Gill rakers were counted on the left outer arch. Data on gill raker number was also collected from literature. Genetic diversity was assessed by nine microsatellite markers (Ozerov et al. 2015. Two methods were used for otolith (sagittae chemistry analysis. Otoliths were dissolved and analyzed for elemental concentrations with ICP-OES (Hägerstrand et al. 2015, or polished to the core and analyzed for core strontium concentration by PIXE

  3. Salmon Site Remedial Investigation Report, Appendix B (Part 2)

    International Nuclear Information System (INIS)

    1999-01-01

    This Salmon Site Remedial Investigation Report provides the results of activities initiated by the U.S. Department of Energy (DOE) to determine if contamination at the Salmon Site poses a current or future risk to human health and the environment. These results were used to develop and evaluate a range of risk-based remedial alternatives. Located in Lamar County, Mississippi, the Salmon Site was used by the U.S. Atomic Energy Commission (predecessor to the DOE) between 1964 and 1970 for two nuclear and two gas explosions conducted deep underground in a salt dome. The testing resulted in the release of radionuclides into the salt dome. During reentry drilling and other site activities, liquid and solid wastes containing radioactivity were generated resulting in surface soil and groundwater contamination. Most of the waste and contaminated soil and water were disposed of in 1993 during site restoration either in the cavities left by the tests or in an injection well. Other radioactive wastes were transported to the Nevada Test Site for disposal. Nonradioactive wastes were disposed of in pits at the site and capped with clean soil and graded. The preliminary investigation showed residual contamination in the Surface Ground Zero mud pits below the water table. Remedial investigations results concluded the contaminant concentrations detected present no significant risk to existing and/or future land users, if surface institutional controls and subsurface restrictions are maintained. Recent sampling results determined no significant contamination in the surface or shallow subsurface. The test cavity resulting from the experiments is contaminated and cannot be economically remediated with existing technologies. The ecological sampling did not detect biological uptake of contaminants in the plants or animals sampled. Based on the current use of the Salmon Site, the following remedial actions were identified to protect both human health and the environment: (1) the

  4. Ground motion effects

    International Nuclear Information System (INIS)

    Blume, J.A.

    1969-01-01

    Ground motion caused by natural earthquakes or by nuclear explosion causes buildings and other structures to respond in such manner as possibly to have high unit stresses and to be subject to damage or-in some cases-collapse. Even minor damage may constitute a hazard to persons within or adjacent to buildings. The risk of damage may well be the governing restraint on the uses of nuclear energy for peaceful purposes. Theory is advanced regarding structural-dynamic response but real buildings and structures are complex, highly variable, and often difficult to model realistically. This paper discusses the state of knowledge, the art of damage prediction and safety precautions, and shows ground motion effects from explosions of underground nuclear devices in the continental United States including events Salmon, Gasbuggy, Boxcar, Faultless and Benham. (author)

  5. Valuing the salmon resource: Columbia River stocks under climate change and fishery enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, D.M.; Scott, M.J.

    1993-04-01

    This paper represents an update to ongoing multidisciplinary research in the area of climate change and associated regional impacts to fisheries and economies. This work particularly deals with the total value of Columbia River salmon and the idea that fish have capital value, articulated here as spawning value. Earlier work dealt solely with the Yakima River spring chinook fishery`s response to climate change and fishery enhancement programs and the associated direct economic effects (Anderson et al. 1992). We have expanded our modeling attempts to examine similar impacts in the Grande Ronde River subbasin of the Columbia River basin, and added the summer steelhead stock to the analysis. Relatively recent developments and improvements in climate change modeling and fishery modeling enabled us to attempt such an endeavor.

  6. Research and Recovery of Snake River Sockeye Salmon, 1995-1996 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Pravecek, Jay J.

    1997-07-01

    In 1991, the National Marine Fisheries Service listed Snake River sockeye salmon Oncorhynchus nerka as endangered under the Endangered Species Act of 1973. Initial steps to recover the species include the establishment of captive broodstocks at the Idaho Department of Fish and Game`s Eagle Fish Hatchery in Eagle, Idaho. Research and recovery activities for sockeye conducted by the Idaho Department of Fish and Game at the Eagle Fish Hatchery during the period April 1, 1995 to April 1, 1996 are covered by this report. The performance of all captive broodstock groups held at Eagle Fish Hatchery is included in this report. No anadromous adults returned to Redfish Lake in 1995. Three adult residual males were captured in a merwin trap and used in the spawning of captive residual females held at Eagle Fish Hatchery.

  7. Spawning frequency of brood dams and sires in a marine fish stock-enhancement hatchery.

    Science.gov (United States)

    Gold, J R; Renshaw, M A; Saillant, E; Vega, R R

    2010-09-01

    Parentage analysis, employing five hypervariable microsatellite markers, was used to follow spawning patterns of red drum Sciaenops ocellatus broodfish in two spawning tanks through most of a calendar year in a marine fish hatchery dedicated to stock enhancement. Five of six dams and all four sires spawned at least once during the year. Variation in dam and sire spawning incidence and in number of progeny produced per dam and per sire translated into reduced genetic effective size (N e) per spawn by 40·6% in one tank and 50·8% in the other. © 2010 The Authors. Journal compilation © 2010 The Fisheries Society of the British Isles.

  8. Changes in the timing of spawning of Baltic cod : possible causes and implications for recruitment

    DEFF Research Database (Denmark)

    Wieland, Kai; Jarre, Astrid; Horbowa, K.

    2000-01-01

    Interannual variations in spawning time, defined as the peak in egg abundance, of cod (Gadus morhua) in the Bornholm Basin, Baltic Sea, were analysed. Effects of water temperature, size and age structure of the spawning stock, abundance of food, and timing of spawning in preceding years were...... temperature during the period of gonadal maturation, density-dependent processes related to the size of the spawning stock, and food availability. The age structure of the spawning stock is suggested to have an additional effect. A high proportion of first-time spawners and decreasing water temperature have...

  9. Harvest Management and Recovery of Snake River Salmon Stocks : Recovery Issues for Threatened and Endangered Snake River Salmon : Technical Report 7 of 11.

    Energy Technology Data Exchange (ETDEWEB)

    Lestelle, Lawrence C.; Gilbertson, Larry G.

    1993-06-01

    Management measures to regulate salmon fishing harvest have grown increasingly complex over the past decade in response to the needs for improved protection for some salmon runs and to alter harvest sharing between fisheries. The development of management plans that adequately address both needs is an immensely complicated task, one that involves a multitude of stocks, each with its own migration patterns and capacity to sustain exploitation. The fishing industry that relies on these fish populations is also highly diverse. The management task is made especially difficult because the stocks are often intermingled on the fishing grounds, creating highly mixed aggregates of stocks and species on which the fisheries operate. This situation is the one confronting harvest managers attempting to protect Snake River salmon. This report provides an overview of some of the factors that will need to be addressed in assessing the potential for using harvest management measures in the recovery of Snake River salmon stocks. The major sections of the report include the following: perspectives on harvest impacts; ocean distribution and in-river adult migration timing; description of management processes and associated fisheries of interest; and altemative harvest strategies.

  10. Spawning phenology and geography of Aleutian Islands and eastern Bering Sea Pacific cod (Gadus macrocephalus)

    Science.gov (United States)

    Neidetcher, Sandra K.; Hurst, Thomas P.; Ciannelli, Lorenzo; Logerwell, Elizabeth A.

    2014-11-01

    Pacific cod (Gadus macrocephalus) is an economically and ecologically important species in the southeastern Bering Sea and Aleutian Islands, yet little is known about the spawning dynamics of Pacific cod in these regions. To address this knowledge gap, we applied a gross anatomical maturity key for Pacific cod to describe temporal and spatial patterns of reproductive status over three winter spawning seasons: 2005, 2006, and 2007. Maturity status of female Pacific cod was assessed by fishery observers during sampling of commercial catches and used to construct maps showing spawning activity in the Bering Sea and Aleutian Islands. Most spawning activity was observed on the Bering Sea shelf and Aleutian Island plateaus between 100 and 200 m depth. Data for those days when a high percentage of spawning stage fish were observed were used to identify areas with concentrations of spawning fish. Spawning concentrations were identified north of Unimak Island, in the vicinity of the Pribilof Islands, at the shelf break near Zhemchug Canyon, and adjacent to islands in the central and western Aleutian Islands along the continental shelf. The spawning season was found to begin in the last days of February or early March and extend through early to mid-April. Variation in spawning time (averaging ~10 days between years) may have been associated with a change from warm (2005) to cold (2007) climate conditions during the study period. Our information on Pacific cod spawning patterns will help inform fishery management decisions, models of spawning and larval dispersal and the spatial structure of the stock.

  11. Juvenile salmonid monitoring in the White Salmon River, Washington, post-Condit Dam removal, 2016

    Science.gov (United States)

    Jezorek, Ian G.; Hardiman, Jill M.

    2017-06-23

    Condit Dam, at river kilometer 5.3 on the White Salmon River, Washington, was breached in 2011 and removed completely in 2012, allowing anadromous salmonids access to habitat that had been blocked for nearly 100 years. A multi-agency workgroup concluded that the preferred salmonid restoration alternative was natural recolonization with monitoring to assess efficacy, followed by a management evaluation 5 years after dam removal. Limited monitoring of salmon and steelhead spawning has occurred since 2011, but no monitoring of juveniles occurred until 2016. During 2016, we operated a rotary screw trap at river kilometer 2.3 (3 kilometers downstream of the former dam site) from late March through May and used backpack electrofishing during summer to assess juvenile salmonid distribution and abundance. The screw trap captured primarily steelhead (Oncorhynchus mykiss; smolts, parr, and fry) and coho salmon (O. kisutch; smolts and fry). We estimated the number of steelhead smolts at 3,851 (standard error = 1,454) and coho smolts at 1,093 (standard error = 412). In this document, we refer to O. mykiss caught at the screw trap as steelhead because they were actively migrating, but because we did not know migratory status of O. mykiss caught in electrofishing surveys, we simply refer to them as O. mykiss or steelhead/rainbow trout. Steelhead and coho smolts tagged with passive integrated transponder tags were subsequently detected downstream at Bonneville Dam on the Columbia River. Few Chinook salmon (O. tshawytscha) fry were captured, possibly as a result of trap location or effects of a December 2015 flood. Sampling in Mill, Buck, and Rattlesnake Creeks (all upstream of the former dam site) showed that juvenile coho were present in Mill and Buck Creeks, suggesting spawning had occurred there. We compared O. mykiss abundance data in sites on Buck and Rattlesnake Creeks to pre-dam removal data. During 2016, age-0 O. mykiss were more abundant in Buck Creek than in 2009 or

  12. Effects of a Novel Fish Transport System on the Health of Adult Fall Chinook Salmon

    Energy Technology Data Exchange (ETDEWEB)

    Geist, David R.; Colotelo, Alison H.; Linley, Timothy J.; Wagner, Katie A.; Miracle, Ann L.

    2016-12-01

    Movement past hydroelectric dams and related in-river structures has important implications for habitat connectivity and population persistence in migratory fish. A major problem is that many of these structures lack effective fish passage facilities, which can fragment spawning and rearing areas and negatively impact recruitment. While traditional fish passage facilities (e.g., ladders, trap and haul) can effectively enable fish to pass over barriers, their capital or operational costs can be significant. We evaluated the utility of a novel transport device that utilizes a flexible tube with differential internal air pressure to pass fish around in-river barriers. Three treatments and a control group were tested. In two of the treatments, adult fall Chinook Salmon nearing maturation were transported through the device via two lengths of tube (12 or 77 m) and their injury, stress, and immune system responses and reproductive function were compared to a third treatment where fish were moved by a standard trap and haul method and also to a control group. We observed no significant differences among the treatment or control groups in post-treatment adult survival, injury or stress. Indicators of immune system response and reproductive readiness were also not significantly different among the four groups. Egg survival was significantly different among the groups, but the differences were highly variable within groups and not consistent with the duration of treatment or degree of handling. Taken together, the results suggest the device did not injure or alter normal physiological functioning of adult fall Chinook Salmon nearing maturation and may provide an effective method for transporting such fish around in-river barriers during their spawning migration. Keywords: Whooshh, transport, in-stream barriers, hydropower

  13. Larval development of certain gamete-spawning scleractinian corals

    Science.gov (United States)

    Babcock, R. C.; Heyward, A. J.

    1986-12-01

    Embryogenesis and larval development were documented in 19 species of hermatypic scleractinians which release gametes during the summer coral spawning season on the Great Barrier Reef. Cleavage of fertilized eggs began approximately 2 h after spawning in all species, and gave rise to blastulae after 7 10 h. Endoderm formation in Platygyra sinensis was by invagination, and this appeared to occur in all species studied. All species observed at 36 h after spawing were mobile and full mobility was reached by 48 h. Settlement of planulae placed in aquaria occurred between 4 and 7 days after fertilization. These results suggest that larval corals produced by most gamete-releasing coral species are likely to be dispersed away from the parent reef.

  14. Major histocompatibility complex diversity is positively associated with stream water temperatures in proximate populations of sockeye salmon.

    Science.gov (United States)

    Larson, W A; Lisi, P J; Seeb, J E; Seeb, L W; Schindler, D E

    2016-09-01

    Local adaptation to heterogeneous environments generates population diversity within species, significantly increasing ecosystem stability and flows of ecosystem services. However, few studies have isolated the specific mechanisms that create and maintain this diversity. Here, we examined the relationship between water temperature in streams used for spawning and genetic diversity at a gene involved in immune function [the major histocompatibility complex (MHC)] in 14 populations of sockeye salmon (Oncorhynchus nerka) sampled across the Wood River basin in south-western Alaska. The largest influence on MHC diversity was lake basin, but we also found a significant positive correlation between average water temperature and MHC diversity. This positive relationship between temperature and MHC diversity appears to have been produced by natural selection at very local scales rather than neutral processes, as no correlation was observed between temperature and genetic diversity at 90 neutral markers. Additionally, no significant relationship was observed between temperature variability and MHC diversity. Although lake basin was the largest driver of differences in MHC diversity, our results also demonstrate that fine-scale differences in water temperature may generate variable selection regimes in populations that spawn in habitats separated by as little as 1 km. Additionally, our results indicated that some populations may be reaching a maximum level of MHC diversity. We postulate that salmon from populations in warm streams may delay spawning until late summer to avoid thermal stress as well as the elevated levels of pathogen prevalence and virulence associated with warm temperatures earlier in the summer. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  15. Incidental spawning of some scombrids in Adriatic or not?

    Directory of Open Access Journals (Sweden)

    Vanja Cikes Kec

    2015-10-01

    Full Text Available During routine monitoring of commercial purse seine catches in 2011, 87 fingerling specimens of scombrids were collected in the southern Adriatic Sea. Sequencing of mitochondrial control region locus inferred that specimens belonged to the Atlantic bluefin tuna, Thunnus thynnus (Linnaeus, 1758 (N=29, bullet tuna, Auxis rochei (Risso, 1810 (N=30 and little tunny, Euthynnus alletteratus, Rafinesque, 1810 (N=28. Due to previously published growth parameters, age of collected specimens was estimated to be approximately 30 days. In order to determine possible location of the spawning event coupled modelling system ROMS-ICHTHYOP was run. Realistic ROMS simulations were made to provide current and density fields for the ICHTHYOP model. ROMS model was forced with realistic surface air-sea fluxes calculated from fine resolution ALADIN model, river inflows, tides and external dynamics. ICHTHYOP was run in the backward mode for 30 days using published investigations on the studied species and its early stage dynamics, such as their growth and developmental stage thermal dependence, lethal temperatures, etc. Apart simulations with coupled modelling system, detailed analysis of prevailing meteorological and oceanographic conditions was made using all available data. Comparison to climatology of the area approved that 2011 had unusually prolonged warm and dry summer season. Occasional inflows of hot and dry air from the northern Africa additionally warm up Adriatic atmosphere. Under these conditions sea surface temperature was up to 2 standard deviations above normal. In the deeper layers, high temperature and salinity were recorded. According to performed simulations it seems that tuna species spawn within the commercial tuna cages (this is not the first evidence of natural spawning within commercial tuna farming facility in the Adriatic, while the other two species most probably opportunistically use positive environmental (abiotic and biotic conditions and

  16. Environmental and biological cues for spawning in the crown-of-thorns starfish.

    Directory of Open Access Journals (Sweden)

    Ciemon Frank Caballes

    Full Text Available Sporadic outbreaks of the coral-eating crown-of-thorns starfish are likely to be due, at least in part, to spatial and temporal variation in reproductive and settlement success. For gonochoric and broadcast spawning species such as crown-of-thorns starfish, spawning synchrony is fundamental for achieving high rates of fertilization. Highly synchronized gamete release within and among distinct populations is typically the result of the entrainment of neurohormonal endogenous rhythms by cues from the environment. In this study, we conducted multiple spawning assays to test the effects of temperature change, reduced salinity and nutrient enrichment of seawater, phytoplankton, gametes (sperm and eggs, and the combined effect of sperm and phytoplankton on the likelihood of spawning in male and female crown-of-thorns starfish. We also investigated sex-specific responses to each of these potential spawning cues. We found that (1 abrupt temperature change (an increase of 4°C induced spawning in males, but less so in females; (2 males often spawned in response to the presence of phytoplankton, but none of the females spawned in response to these cues; (3 the presence of sperm in the water column induced males and females to spawn, although additive and synergistic effects of sperm and phytoplankton were not significant; and (4 males are more sensitive to the spawning cues tested and most likely spawn prior to females. We propose that environmental cues act as spawning 'inducers' by causing the release of hormones (gonad stimulating substance in sensitive males, while biological cues (pheromones from released sperm, in turn, act as spawning 'synchronizers' by triggering a hormonal cascade resulting in gamete shedding by conspecifics. Given the immediate temporal linkage between the timing of spawning and fertilization events, variability in the extent and synchronicity of gamete release will significantly influence reproductive success and may account

  17. An accurate method for measuring triploidy of larval fish spawns

    Science.gov (United States)

    Jenkins, Jill A.; Draugelis-Dale, Rassa O.; Glennon, Robert; Kelly, Anita; Brown, Bonnie L.; Morrison, John

    2017-01-01

    A standard flow cytometric protocol was developed for estimating triploid induction in batches of larval fish. Polyploid induction treatments are not guaranteed to be 100% efficient, thus the ability to quantify the proportion of triploid larvae generated by a particular treatment helps managers to stock high-percentage spawns and researchers to select treatments for efficient triploid induction. At 3 d posthatch, individual Grass Carp Ctenopharyngodon idella were mechanically dissociated into single-cell suspensions; nuclear DNA was stained with propidium iodide then analyzed by flow cytometry. Following ploidy identification of individuals, aliquots of diploid and triploid cell suspensions were mixed to generate 15 levels (0–100%) of known triploidy (n = 10). Using either 20 or 50 larvae per level, the observed triploid percentages were lower than the known, actual values. Using nonlinear regression analyses, quadratic equations solved for triploid proportions in mixed samples and corresponding estimation reference plots allowed for predicting triploidy. Thus, an accurate prediction of the proportion of triploids in a spawn can be made by following a standard larval processing and analysis protocol with either 20 or 50 larvae from a single spawn, coupled with applying the quadratic equations or reference plots to observed flow cytometry results. Due to the universality of triploid DNA content being 1.5 times the diploid level and because triploid fish consist of fewer cells than diploids, this method should be applicable to other produced triploid fish species, and it may be adapted for use with bivalves or other species where batch analysis is appropriate.

  18. Cloned and outbred Atlantic salmon display equal parasite dispersion when infected with the salmon louse

    OpenAIRE

    Glover, Kevin; Hansen, Tom Johnny; Besnier, Francois; Solberg, Monica Favnebøe; Fjelldal, Per Gunnar; Sørvik, Anne Grete Eide; Dalvin, Sussie; Nilsen, Frank

    2017-01-01

    The salmon louse is an ectoparasitic copepod that infects salmonids in the marine environment. This parasite causes a major economic and biological challenge to the Atlantic salmon farming industry, and efforts to increase the resistance of salmon to this parasite are ongoing. We used a novel approach to investigate the relative importance of genetic and non-genetic factors on individual infection levels with this parasite. A collectively-reared group of 50 cloned (no genetic variation) and 5...

  19. Effects of emergence time and early social rearing environment on behaviour of Atlantic salmon: Consequences for juvenile fitness and smolt migration

    DEFF Research Database (Denmark)

    Larsen, Martin Hage; Johnsson, Jörgen I.; Winberg, Svante

    2015-01-01

    Consistent individual differences in behaviour have been well documented in a variety of animal taxa, but surprisingly little is known about the fitness and life-history consequences of such individual variation. In wild salmonids, the timing of fry emergence from gravel spawning nests has been...... whether behavioural traits measured in the laboratory predict growth, survival, and migration status in the wild. Atlantic salmon fry were sorted with respect to emergence time from artificial spawning nest into three groups: early, intermediate, and late. These emergence groups were hatchery...... no significant effects on survival, growth, and migration status in the stream, although migration propensity was 1.4 to 1.9 times higher for early emerging individuals that were reared separately. In addition, despite individuals showing considerable variation in behaviour across treatment groups...

  20. Risk, risk conflicts, sub-politics and social and environmental accounting and accountability in Scottish salmon farming

    NARCIS (Netherlands)

    Georgakopoulos, G.; Thomson, I.

    2008-01-01

    Purpose To offer a theoretical analysis, inspired by contemporary research into risk, of the social and environmental accounting processes observed in an empirical study on Scottish salmon farming. Methodology / Approach This paper used a Grounded Theory approach. Empirical evidence was collected on

  1. Hydrologic Alterations from Climate Change Inform Assessment of Ecological Risk to Pacific Salmon in Bristol Bay, Alaska.

    Science.gov (United States)

    Wobus, Cameron; Prucha, Robert; Albert, David; Woll, Christine; Loinaz, Maria; Jones, Russell; Travers, Constance

    2015-01-01

    We developed an integrated hydrologic model of the upper Nushagak and Kvichak watersheds in the Bristol Bay region of southwestern Alaska, a region under substantial development pressure from large-scale copper mining. We incorporated climate change scenarios into this model to evaluate how hydrologic regimes and stream temperatures might change in a future climate, and to summarize indicators of hydrologic alteration that are relevant to salmon habitat ecology and life history. Model simulations project substantial changes in mean winter flow, peak flow dates, and water temperature by 2100. In particular, we find that annual hydrographs will no longer be dominated by a single spring thaw event, but will instead be characterized by numerous high flow events throughout the winter. Stream temperatures increase in all future scenarios, although these temperature increases are moderated relative to air temperatures by cool baseflow inputs during the summer months. Projected changes to flow and stream temperature could influence salmon through alterations in the suitability of spawning gravels, changes in the duration of incubation, increased growth during juvenile stages, and increased exposure to chronic and acute temperature stress. These climate-modulated changes represent a shifting baseline in salmon habitat quality and quantity in the future, and an important consideration to adequately assess the types and magnitude of risks associated with proposed large-scale mining in the region.

  2. Potential responses to climate change in organisms with complex life histories: evolution and plasticity in Pacific salmon.

    Science.gov (United States)

    Crozier, L G; Hendry, A P; Lawson, P W; Quinn, T P; Mantua, N J; Battin, J; Shaw, R G; Huey, R B

    2008-05-01

    Salmon life histories are finely tuned to local environmental conditions, which are intimately linked to climate. We summarize the likely impacts of climate change on the physical environment of salmon in the Pacific Northwest and discuss the potential evolutionary consequences of these changes, with particular reference to Columbia River Basin spring/summer Chinook (Oncorhynchus tshawytscha) and sockeye (Oncorhynchus nerka) salmon. We discuss the possible evolutionary responses in migration and spawning date egg and juvenile growth and development rates, thermal tolerance, and disease resistance. We know little about ocean migration pathways, so cannot confidently suggest the potential changes in this life stage. Climate change might produce conflicting selection pressures in different life stages, which will interact with plastic (i.e. nongenetic) changes in various ways. To clarify these interactions, we present a conceptual model of how changing environmental conditions shift phenotypic optima and, through plastic responses, phenotype distributions, affecting the force of selection. Our predictions are tentative because we lack data on the strength of selection, heritability, and ecological and genetic linkages among many of the traits discussed here. Despite the challenges involved in experimental manipulation of species with complex life histories, such research is essential for full appreciation of the biological effects of climate change.

  3. Hydrologic Alterations from Climate Change Inform Assessment of Ecological Risk to Pacific Salmon in Bristol Bay, Alaska.

    Directory of Open Access Journals (Sweden)

    Cameron Wobus

    Full Text Available We developed an integrated hydrologic model of the upper Nushagak and Kvichak watersheds in the Bristol Bay region of southwestern Alaska, a region under substantial development pressure from large-scale copper mining. We incorporated climate change scenarios into this model to evaluate how hydrologic regimes and stream temperatures might change in a future climate, and to summarize indicators of hydrologic alteration that are relevant to salmon habitat ecology and life history. Model simulations project substantial changes in mean winter flow, peak flow dates, and water temperature by 2100. In particular, we find that annual hydrographs will no longer be dominated by a single spring thaw event, but will instead be characterized by numerous high flow events throughout the winter. Stream temperatures increase in all future scenarios, although these temperature increases are moderated relative to air temperatures by cool baseflow inputs during the summer months. Projected changes to flow and stream temperature could influence salmon through alterations in the suitability of spawning gravels, changes in the duration of incubation, increased growth during juvenile stages, and increased exposure to chronic and acute temperature stress. These climate-modulated changes represent a shifting baseline in salmon habitat quality and quantity in the future, and an important consideration to adequately assess the types and magnitude of risks associated with proposed large-scale mining in the region.

  4. Monitoring and Evaluation of Supplemented Spring Chinook Salmon and Life Histories of Wild Summer Steelhead in the Grande Ronde Basin, 2007 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Boe, Stephen J.; Crump, Carrie A.; Weldert, Rey L. [Confederated Tribes of the Umatilla Indian Reservation

    2009-04-10

    This is the ninth annual report for a multi-year project designed to monitor and evaluate supplementation of endemic spring Chinook salmon in Catherine Creek and the upper Grande Ronde River. These two streams historically supported anadromous fish populations that provided significant tribal and non-tribal fisheries, but in recent years, have experienced severe declines in abundance. Conventional and captive broodstock supplementation methods are being used to restore these spring Chinook salmon populations. Spring Chinook salmon populations in Catherine Creek and the upper Grande Ronde River, and other streams in the Snake River Basin have experienced severe declines in abundance over the past two decades (Nehlsen et al. 1991). A supplementation program was initiated in Catherine Creek and the upper Grande Ronde River, incorporating the use of both captive and conventional broodstock methods, in order to prevent extinction in the short term and eventually rebuild populations. The captive broodstock component of the program (BPA Project 199801001) uses natural-origin parr collected by seining and reared to maturity at facilities near Seattle, Washington (Manchester Marine Laboratory) and Hood River, Oregon (Bonneville Hatchery). Spawning occurs at Bonneville Hatchery, and resulting progeny are reared in hatcheries. Shortly before outmigration in the spring, juveniles are transferred to acclimation facilities. After an acclimation period of about 2-4 weeks, volitional release begins. Any juveniles remaining after the volitional release period are forced out. The conventional broodstock component uses returning adults collected at traps near the spawning areas, transported to Lookingglass Hatchery near Elgin, Oregon, held, and later spawned. The resulting progeny are reared, acclimated, and released similar to the captive broodstock component. All progeny released receive one or more marks including a fin (adipose) clip, codedwire tag, PIT tag, or visual implant

  5. Modeling Investigation of Spring Chinook Salmon Habitat in San Joaquin River Restoration Program

    Science.gov (United States)

    Liu, L.; Ramires, J.

    2013-12-01

    As the second longest river in California, the San Joaquin River (SJR) is a vital natural resource to numerous residents and industries and provides an array of activities within Central Valley, home to some of California's most productive agricultural areas. Originating in the high Sierra Nevada, mainly from snowmelt and runoff, and passing through the middle sections including Fresno and Madera counties, eventually the SJR conjoins with the Sacramento River, constructing the largest river delta on the west coast of North America. Along with human necessities, the river used to be crucial for the propagation and survivability of Chinook salmon and other aquatic and wildlife. However, the SJR has experienced hydraulic disconnection throughout certain reaches due to extensive water diversion. Indigenous salmon populations have been degraded over the years due to insufficient flows and anthropogenic activities. In 2006, to maintain salmon and other fish populations to a point of self-sustainment, the San Joaquin River Restoration Project (SJRRP) was established to restore flows along the SJR from Friant Dam to the confluence of the Merced River by routing the original SJR in different pathways. One of the major tasks of the SJRRP, so called 'Reach 4B Project', was to modify and improve channel capacity of reach 4B, east side bypass and Mariposa bypass of the SJR. Multiple scenarios for the alteration and modification of the SJR water pathway were designed to ensure fish passage by retrofitting existing channels and to provide adequate flow throughout the study area. The goal of the SJRRP project 4B was to provide an efficient passage for adult Chinook salmon to spawning beds further upstream and a safe route for yearling to the delta. The objective of this research project is to characterize the stream properties (current velocities, depth, etc.) of each proposed alternative in Project 4B2 under the same upstream conditions using a modeling method. A depth

  6. Toxicity of road deicing salt (NaCl) and copper (Cu) to fertilization and early developmental stages of Atlantic salmon (Salmo salar).

    Science.gov (United States)

    Mahrosh, Urma; Kleiven, Merethe; Meland, Sondre; Rosseland, Bjørn Olav; Salbu, Brit; Teien, Hans-Christian

    2014-09-15

    In many countries, salting of ice or snow covered roads may affect aquatic organisms in the catchment directly or indirectly by mobilization of toxic metals. We studied the toxicity of road deicing salt and copper (Cu) on the vulnerable early life stages of Atlantic salmon (Salmo salar), from fertilization till hatching. Controlled episodic exposure to road salt (≥ 5,000 mg/L) during fertilization resulted in reduced swelling and less percent egg survival. Exposure to Cu both during and post fertilization caused delayed hatching. Larval deformities were, however found as an additional effect, when eggs were exposed to high salt concentration (≥ 5,000 mg/L) mixed with Cu (10 μg Cu/L) during fertilization. Thus, it appears that the sensitivity of early developmental stages of Atlantic salmon increased when exposed to these stressors, and road salt application during spawning can pose threat to Atlantic salmon in water bodies receiving road runoff. The study gives insight on assessment and management of risks on Atlantic salmon population posed by road related hazardous chemicals. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. A Two-Stage Information-Theoretic Approach to Modeling Landscape-Level Attributes and Maximum Recruitment of Chinook Salmon in the Columbia River Basin.

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, William L.; Lee, Danny C.

    2000-11-01

    Many anadromous salmonid stocks in the Pacific Northwest are at their lowest recorded levels, which has raised questions regarding their long-term persistence under current conditions. There are a number of factors, such as freshwater spawning and rearing habitat, that could potentially influence their numbers. Therefore, we used the latest advances in information-theoretic methods in a two-stage modeling process to investigate relationships between landscape-level habitat attributes and maximum recruitment of 25 index stocks of chinook salmon (Oncorhynchus tshawytscha) in the Columbia River basin. Our first-stage model selection results indicated that the Ricker-type, stock recruitment model with a constant Ricker a (i.e., recruits-per-spawner at low numbers of fish) across stocks was the only plausible one given these data, which contrasted with previous unpublished findings. Our second-stage results revealed that maximum recruitment of chinook salmon had a strongly negative relationship with percentage of surrounding subwatersheds categorized as predominantly containing U.S. Forest Service and private moderate-high impact managed forest. That is, our model predicted that average maximum recruitment of chinook salmon would decrease by at least 247 fish for every increase of 33% in surrounding subwatersheds categorized as predominantly containing U.S. Forest Service and privately managed forest. Conversely, mean annual air temperature had a positive relationship with salmon maximum recruitment, with an average increase of at least 179 fish for every increase in 2 C mean annual air temperature.

  8. Migratory Behavior of Adult Spring Chinook Salmon in the Willamette River and its Tributaries: Completion report

    Energy Technology Data Exchange (ETDEWEB)

    Schreck, Carl B.

    1994-01-01

    Migration patterns of adult spring chinook salmon above Willamette Falls differed depending on when the fish passed the Falls, with considerable among-fish variability. Early-run fish often terminated their migration for extended periods of time, in association with increased flows and decreased temperatures. Mid-run fish tended to migrate steadily upstream at a rate of 30-40 km/day. Late-run fish frequently ceased migrating or fell back downstream after migrating 10-200 km up the Willamette River or its tributaries; this appeared to be associated with warming water during summer and resulted in considerable mortality. Up to 40% of the adult salmon entering the Willamette River System above Willamette Falls (i.e. counted at the ladder) may die before reaching upriver spawning areas. Up to 10% of the fish passing up over Willamette Falls may fall-back below the Falls; some migrate to the Columbia River or lower Willamette River tributaries. If rearing conditions at hatcheries affect timing of adult returns because of different juvenile development rates and improper timing of smolt releases, then differential mortality in the freshwater segment of the adult migrations may confound interpretation of studies evaluating rearing practices.

  9. It's a bear market: evolutionary and ecological effects of predation on two wild sockeye salmon populations.

    Science.gov (United States)

    Lin, J E; Hard, J J; Naish, K A; Peterson, D; Hilborn, R; Hauser, L

    2016-05-01

    Predation can affect both phenotypic variation and population productivity in the wild, but quantifying evolutionary and demographic effects of predation in natural environments is challenging. The aim of this study was to estimate selection differentials and coefficients associated with brown bear (Ursus arctos) predation in wild sockeye salmon (Oncorhynchus nerka) populations spawning in pristine habitat that is often subject to intense predation pressure. Using reconstructed genetic pedigrees, individual reproductive success (RS) was estimated in two sockeye salmon populations for two consecutive brood years with very different predation intensities across brood years. Phenotypic data on individual adult body length, body depth, stream entry timing and reproductive lifespan were used to calculate selection coefficients based on RS, and genetic variance components were estimated using animal models. Bears consistently killed larger and more recently arrived adults, although selection differentials were small. In both populations, mean RS was higher in the brood year experiencing lower predation intensity. Selection coefficients were similar across brood years with different levels of predation, often indicating stabilizing selection on reproductive lifespan as well as directional selection for longer reproductive lifespan. Despite these selection pressures, genetic covariation of morphology, phenology and lifespan appears to have maintained variation in spawner body size and stream entry timing in both populations. Our results therefore suggest considerable demographic but limited evolutionary effects of bear predation in the two study populations.

  10. Sexual conflict inhibits female mate choice for major histocompatibility complex dissimilarity in Chinook salmon.

    Science.gov (United States)

    Garner, Shawn R; Bortoluzzi, Romina N; Heath, Daniel D; Neff, Bryan D

    2010-03-22

    In many species females prefer major histocompatibility complex (MHC) dissimilar mates, which may improve offspring resistance to pathogens. However, sexual conflict may interfere with female preference when males attempt to mate with all females, regardless of compatibility. Here we used semi-natural spawning channels to examine how mating behaviour and genetic similarity at the MHC class II peptide binding region affected parentage patterns in Chinook salmon (Oncorhynchus tshawytscha). We found that females directed aggression at more MHC-similar males than expected by chance, providing a possible mechanism of female MHC choice in salmon. Males also directed aggression towards MHC-similar females, which was consistent with males harassing unreceptive mates. Males' aggression was positively correlated with their reproductive success, and it appeared to overcome female aversion to mating with MHC-similar males, as females who were the target of high levels of male aggression had lower than expected MHC divergence in their offspring. Indeed, offspring MHC divergence was highest when the sex ratio was female-biased and male harassment was likely to be less intense. These data suggest that male harassment can reduce female effectiveness in selecting MHC-compatible mates, and sexual conflict can thus have an indirect cost to females.

  11. Grande Ronde Endemic Spring Chinook Salmon Supplementation Project; Lostine River Operations and Maintenance 2007 Smolt Acclimation and Adult Return Report.

    Energy Technology Data Exchange (ETDEWEB)

    Zollman, Richard L.; Eschler, Russell; Sealey, Shawn [Nez Perce Tribe

    2009-03-31

    The Nez Perce Tribe (NPT), through funding provided by the Bonneville Power Administration (BPA), has implemented a Chinook salmon supplementation program (250,000 smolts) on the Lostine River, a tributary to the Grande Ronde River of Oregon. The Grande Ronde Endemic Spring Chinook Salmon Supplementation project, which involves supplementation of the Upper Grande Ronde River and Catherine Creek in addition to the Lostine River, was established to prevent extirpation and increase the number of threatened Snake River spring/summer Chinook salmon (Oncorhynchus tshawytscha) returning to the Grande Ronde River. This report covers the eleventh season (1997-2007) of adult Chinook salmon broodstock collection in the Lostine River and the ninth season (1999-2007) of acclimation of resulting Lostine River progeny. Production of Lostine River spring Chinook salmon smolts currently occurs at Lookingglass Fish Hatchery (LGH). The Lostine River supplementation program utilizes two strategies to obtain egg source for production of smolts for supplementation: captive broodstock and conventional broodstock. The captive broodstock strategy involves (1) capture of natural juvenile spring Chinook salmon smolts from the Lostine River, (2) rearing those to adult and spawning them, and (3) rearing the resultant progeny for eventual acclimation and release back into the Lostine River. The conventional broodstock strategy involves (1) capture of natural and hatchery origin adults returning to the Lostine River, (2) holding those adults and spawning them, and (3) rearing the resultant progeny for acclimation and release back into the Lostine River. This report focuses on (1) the trapping and collection of adult spring Chinook salmon that return to the Lostine River, which provides the broodstock source for the conventional strategy and (2) the acclimation and release of juvenile spring Chinook salmon produced from the captive broodstock and conventional broodstock strategies In 2007

  12. Sardine and anchovy spawning as related to temperature and upwelling in the California current system

    Energy Technology Data Exchange (ETDEWEB)

    Lluch-Belda, D.; Lluch-Cota, D.B.; Hernandez-Vazquez, S.H.; Salinas-Zavala, C.A. (Centro de Investigaciones Biologicas de Baja California Sur, A.C., (Mexico)); Schwartzlose, R.A. (Univ. of California, La Jolla (United States))

    1991-11-01

    Sardine and anchovy spawning was analyzed regarding its relation to sea-surface temperature and upwelling, using CalCOFI cruise data and Bakun's upwelling indices. Previous reports of temperature ranges for sardine and anchovy spawning have not taken into account the distribution of SST and have mostly referenced the cooler spawning area of the species. By obtaining the proportion of positive stations to total sampled stations for each tenth of a degree Celsius in the SST distribution, the authors were able to discriminate the ranges of preferred temperatures of spawning for both species. Sardines spawn in a much wider temperature range (13-25C) than anchovy (11.5-16.5C). Two maxima of spawning occur in the California Current: at 15C and 23C. An additional peak is present in the Gulf of California at about 19C. Only one maximum is evident for anchovy spawning, at about 14C. The distribution of spawning as a function of upwelling was also analyzed for both species. There is a maximum for sardines at intermediate values of upwelling. There are two maxima for anchovy: a minor one at low levels of upwelling and a major one at the maximum values of upwelling. They conclude that sardines are eurythermic as compared to anchovies, but spawn only at intermediate values of upwelling, whereas anchovies are stenothermic but spawn at much wider ranges of upwelling, particularly at low and high values. The differences suggest exclusive competition, but more detailed analyses are needed.

  13. AFSC/ABL: Chum salmon allozyme baseline

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Allozymes from 46 loci were analyzed from chum salmon (Oncorhynchus keta) collected at 61 locations in southeast Alaska and northern British Columbia. Of the 42...

  14. Pacific Northwest Salmon Habitat Project Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the Pacific Northwest Salmon Habitat Project Database Across the Pacific Northwest, both public and private agents are working to improve riverine habitat for a...

  15. CROOS - Collaborative Research on Oregon Ocean Salmon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Goal 1: Improve understanding of salmon ocean ecology by integrating stock-specific distribution patterns over space and time with biological and environmental data....

  16. Snake River Sockeye Salmon Habitat and Limnological Research; 2001 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Kohler, Andre E.; Taki, Doug (Shoshone-Bannock Tribes, Fort Hall, ID); Griswold, Robert G. (Biolines, Stanley, ID)

    2004-08-01

    In March 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list the Snake River sockeye salmon Oncorhynchus nerka as endangered. As a result of that petition the Snake River sockeye salmon was officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991, the Snake River Sockeye Salmon Habitat and Limnological Research Program was implemented (Project Number 91-71, Intergovernmental Contract Number DE-BI79-91bp22548). This project is part of an interagency effort to prevent the extinction of the Redfish Lake stock of O. nerka. The Bonneville Power Administration (BPA) provides funding for this interagency recovery program through the Northwest Power Planning Council Fish and Wildlife Program (Council). Collaborators in the recovery effort include the National Marine Fisheries Service (NMFS), the Idaho Department of Fish and Game (IDFG), the University of Idaho (UI), U.S. Forest Service (USFS), and the Shoshone-Bannock Tribe (SBT). This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the 2001 calendar year. Project objectives include: (1) monitor over-winter survival and emigration of juvenile anadromous O. nerka stocked from the captive rearing program; (2) fertilize Redfish Lake, fertilization of Pettit and Alturas lakes was suspended for this year; (3) conduct kokanee (non-anadromous O. nerka) population surveys; (4) monitor spawning kokanee escapement and estimate fry recruitment on Fishhook, Alturas Lake, and Stanley Lake creeks; (5) evaluate potential competition and predation interactions between stocked juvenile O. nerka and a variety of fish species in Redfish, Pettit, and Alturas lakes; (6) monitor limnological parameters of Sawtooth Valley lakes to assess lake productivity.

  17. Snake River sockeye salmon habitat and limnological research, annual report 1999

    International Nuclear Information System (INIS)

    Griswold, Robert G.

    2001-01-01

    In March 1990, the Shoshone-Bannock Tribes petitioned the National Marine Fisheries Service (NMFS) to list the Snake River sockeye salmon (Oncorhynchus nerka) as endangered. As a result of that petition the Snake River sockeye salmon was officially listed as endangered in November 1991 under the Endangered Species Act (56 FR 58619). In 1991 the Snake River Sockeye Salmon Habitat and Limnological Research Program was implemented (Project Number 91-71, Intergovernmental Contract Number DE-BI79-91bp22548). This project is part of an interagency effort to prevent the extinction of the Redfish Lake stock of O. nerka. The Bonneville Power Administration (BPA) provides funding for this inter-agency recovery program through the Northwest Power Planning Council Fish and Wildlife Program (NPPCFWP). Collaborators in the recovery effort include the National Marine Fisheries Service (NMFS), the Idaho Department of Fish and Game (IDFG), the University of Idaho (UI), U.S. Forest Service (USFS), and the Shoshone-Bannock Tribe (SBT). This report summarizes activities conducted by Shoshone-Bannock Tribal Fisheries Department personnel during the 1999 calendar year. Project objectives include: (1) monitor over-winter survival and emigration of juvenile anadromous O. nerka stocked from the captive rearing program; (2) fertilize Pettit, and Alturas lakes, fertilization of Redfish Lake was suspended for this year; (3) conduct kokanee (nonanadromous O. nerka) population surveys; (4) monitor spawning kokanee escapement and estimate fry recruitment on Fishhook, Alturas Lake, and Stanley Lake creeks; (5) evaluate potential competition and predation interactions between stocked juvenile O. nerka and a variety of fish species in Redfish, Pettit, and Alturas lakes; (6) examine diet of emigrating O. nerka smolts; (7) monitor limnological parameters of Sawtooth Valley lakes to assess lake productivity

  18. Salmon River Habitat Enhancement. 1990 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Mike

    1991-12-01

    The annual report contains three individual subproject sections detailing tribal fisheries work completed during the summer and fall of 1990. Subproject I contains summaries of evaluation/monitoring efforts associated with the Bear Valley Creek, Idaho enhancement project. Subproject II contains an evaluation of the Yankee Fork of the Salmon River habitat enhancement project. Subproject III concerns the East Fork of the Salmon River, Idaho.

  19. LABORATORY DIAGNOSIS OF INFECTIOUS SALMON ANEMIA (ISA)

    DEFF Research Database (Denmark)

    Schyth, Brian Dall; Olesen, Niels Jørgen; Østergaard, Peter

    The first outbreak of ISA on the Faroe Islands was diagnosed in March 2000. Despite intensive surveillance, control and eradication of ISA, the disease has since spread to most of the Faroe Islands affecting about half of the 23 aquaculture farms. Sampling and laboratory diagnosis of ISA is perfo...... characterisation of the virus causing infectious salmon anemia in Atlantic salmon (Salmo salar L): an orthomyxo-like virus in a teleost....

  20. Quantifying Temperature Effects on Fall Chinook Salmon

    Energy Technology Data Exchange (ETDEWEB)

    Jager, Yetta [ORNL

    2011-11-01

    The motivation for this study was to recommend relationships for use in a model of San Joaquin fall Chinook salmon. This report reviews literature pertaining to relationships between water temperature and fall Chinook salmon. The report is organized into three sections that deal with temperature effects on development and timing of freshwater life stages, temperature effects on incubation survival for eggs and alevin, and temperature effects on juvenile survival. Recommendations are made for modeling temperature influences for all three life stages.

  1. Evaluation of the behavior and movement patterns of adult coho salmon and steelhead in the North Fork Toutle River, Washington, 2005-2009

    Science.gov (United States)

    Liedtke, Theresa L.; Kock, Tobias J.; Rondorf, Dennis W.

    2013-01-01

    Creeks, the locations where trap-and-haul fish were released during 2005–2006. None of the tagged fish left the tributaries where they were released, but four radio tags were detected near the release sites, and it was not possible to determine if this was because the transmitters were regurgitated, or if some of the tagged fish had died. The results from this portion of the study indicated that trap-and-haul fish remain in the tributaries where they can spawn, but the trap-and-haul process is labor-intensive, and handling stress and mortality could occur. Tagged-fish releases upstream of the FCF showed that the SRS spillway was a complete migration barrier for all coho salmon and most steelhead. We released a total of 20 radio-tagged coho salmon and 23 radio-tagged steelhead during 2005–2007. No tagged coho salmon passed upstream through the SRS spillway, whereas 13 percent of the radio-tagged steelhead did migrate upstream through the structure. Radio-tagged coho salmon and steelhead that did not pass upstream remained in the FCF–SRS reach for an average of 7.5 and 16.1 d, respectively, before moving downstream. These data show that trap-and-haul releases of fish immediately upstream of the FCF would not be beneficial to coho salmon and steelhead populations in the system. Releasing tagged fish into the sediment plain was only moderately successful for coho salmon,

  2. Selection by higher-order effects of salinity and bacteria on early life-stages of Western Baltic spring-spawning herring.

    Science.gov (United States)

    Poirier, Maude; Listmann, Luisa; Roth, Olivia

    2017-07-01

    Habitat stratification by abiotic and biotic factors initiates divergence of populations and leads to ecological speciation. In contrast to fully marine waters, the Baltic Sea is stratified by a salinity gradient that strongly affects fish physiology, distribution, diversity and virulence of important marine pathogens. Animals thus face the challenge to simultaneously adapt to the concurrent salinity and cope with the selection imposed by the changing pathogenic virulence. Western Baltic spring-spawning herring ( Clupea harengus ) migrate to spawning grounds characterized by different salinities to which herring are supposedly adapted. We hypothesized that herring populations do not only have to cope with different salinity levels but that they are simultaneously exposed to higher-order effects that accompany the shifts in salinity, that is induced pathogenicity of Vibrio bacteria in lower saline waters. To experimentally evaluate this, adults of two populations were caught in their spawning grounds and fully reciprocally crossed within and between populations. Larvae were reared at three salinity levels, representing the spawning ground salinity of each of the two populations, or Atlantic salinity conditions resembling the phylogenetic origin of Clupea harengus . In addition, larvae were exposed to a Vibrio spp . infection. Life-history traits and gene expression analysis served as response variables. Herring seem adapted to Baltic Sea conditions and cope better with low saline waters. However, upon a bacterial infection, herring larvae suffer more when kept at lower salinities implying reduced resistance against Vibrio or higher Vibrio virulence. In the context of recent climate change with less saline marine waters in the Baltic Sea, such interactions may constitute key future stressors.

  3. Tucannon River Spring Chinook Salmon Captive Brood Program, FY 2000 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Bumgarner, Joseph D.; Gallinat, Michael P.

    2001-06-01

    This report summarizes the objectives, tasks, and accomplishments of the Tucannon River spring chinook captive brood program from program inception (1997) through April 2001. The WDFW initiated a captive broodstock program in 1997. The overall goal of the Tucannon River captive broodstock program is for the short-term, and eventually long-term, rebuilding of the Tucannon River spring chinook salmon run, with the hope that natural production will eventually sustain itself. The project goal is to rear captive salmon to adults, spawn them, rear their progeny, and release approximately 150,000 smolts annually into the Tucannon River between 2003-2007. These smolt releases, in combination with the current hatchery supplementation program (132,000 smolts), and wild production, is expected to produce 600-700 returning adult spring chinook to the Tucannon River each year from 2005-2010. The Master Plan, Environmental Assessment, and most facility modifications at LFH were completed for the Tucannon River spring chinook captive broodstock program during FY2000 and FY2001. DNA samples collected since 1997 have been sent to the WDFW genetics lab in Olympia for baseline DNA analysis. Results from the genetic analysis are not available at this time. The captive broodstock program is planned to collect fish from five (1997-2001) brood years (BY). The captive broodstock program was initiated with 1997 BY juveniles, and the 2000 BY fish have been selected. As of April 30, 2001, WDFW has 172 BY 1997, 262 BY 1998, 407 BY 1999, and approximately 1,190 BY 2000 fish on hand at LFH. Twelve of 13 mature 97 BY females were spawned in 2000. Total eggtake was 14,813. Mean fecundity was 1,298 eggs/female based on 11 fully spawned females. Egg survival to eye-up was 47.3%. This low survival was expected for three year old captive broodstock females. As of April 30, 2001, WDFW has 4,211 captive broodstock progeny on hand. These fish will be tagged with blank wire tag without fin clips and

  4. Tucannon River spring chinook salmon captive brood program, FY 2000 annual report; ANNUAL

    International Nuclear Information System (INIS)

    Bumgarner, Joseph D.; Gallinat, Michael P.

    2001-01-01

    This report summarizes the objectives, tasks, and accomplishments of the Tucannon River spring chinook captive brood program from program inception (1997) through April 2001. The WDFW initiated a captive broodstock program in 1997. The overall goal of the Tucannon River captive broodstock program is for the short-term, and eventually long-term, rebuilding of the Tucannon River spring chinook salmon run, with the hope that natural production will eventually sustain itself. The project goal is to rear captive salmon to adults, spawn them, rear their progeny, and release approximately 150,000 smolts annually into the Tucannon River between 2003-2007. These smolt releases, in combination with the current hatchery supplementation program (132,000 smolts), and wild production, is expected to produce 600-700 returning adult spring chinook to the Tucannon River each year from 2005-2010. The Master Plan, Environmental Assessment, and most facility modifications at LFH were completed for the Tucannon River spring chinook captive broodstock program during FY2000 and FY2001. DNA samples collected since 1997 have been sent to the WDFW genetics lab in Olympia for baseline DNA analysis. Results from the genetic analysis are not available at this time. The captive broodstock program is planned to collect fish from five (1997-2001) brood years (BY). The captive broodstock program was initiated with 1997 BY juveniles, and the 2000 BY fish have been selected. As of April 30, 2001, WDFW has 172 BY 1997, 262 BY 1998, 407 BY 1999, and approximately 1,190 BY 2000 fish on hand at LFH. Twelve of 13 mature 97 BY females were spawned in 2000. Total eggtake was 14,813. Mean fecundity was 1,298 eggs/female based on 11 fully spawned females. Egg survival to eye-up was 47.3%. This low survival was expected for three year old captive broodstock females. As of April 30, 2001, WDFW has 4,211 captive broodstock progeny on hand. These fish will be tagged with blank wire tag without fin clips and

  5. Tucannon River Spring Chinook Salmon Captive Broodstock Program, Annual Report 2001.

    Energy Technology Data Exchange (ETDEWEB)

    Gallinat, Michael P.; Bumgarner, Joseph D.

    2002-05-01

    This report summarizes the objectives, tasks, and accomplishments of the Tucannon River spring chinook captive brood during 2001. The WDFW initiated a captive broodstock program in 1997. The overall goal of the Tucannon River captive broodstock program is for the short-term, and eventually long-term, rebuilding of the Tucannon River spring chinook salmon run, with the hope that natural production will sustain itself. The project goal is to rear captive salmon selected from the supplementation program to adults, spawn them, rear their progeny, and release approximately 150,000 smolts annually into the Tucannon River between 2003-2007. These smolt releases, in combination with the current hatchery supplementation program (132,000 smolts) and wild production, are expected to produce 600-700 returning adult spring chinook to the Tucannon River each year from 2005-2010. The captive broodstock program will collect fish from five (1997-2001) brood years (BY). The captive broodstock program was initiated with 1997 BY juveniles, and the 2001 BY fish have been selected. As of Jan 1, 2002, WDFW has 17 BY 1997, 159 BY 1998, 316 BY 1999, 448 BY 2000, and approximately 1,200 BY 2001 fish on hand at LFH. The 2001 eggtake from the 1997 brood year (Age 4) was 233,894 eggs from 125 ripe females. Egg survival was 69%. Mean fecundity based on the 105 fully spawned females was 1,990 eggs/female. The 2001 eggtake from the 1998 brood year (Age 3) was 47,409 eggs from 41 ripe females. Egg survival was 81%. Mean fecundity based on the 39 fully spawned females was 1,160 eggs/female. The total 2001 eggtake from the captive brood program was 281,303 eggs. As of May 1, 2002 we have 171,495 BY 2001 captive brood progeny on hand. A total of 20,592 excess fish were marked as parr (AD/CWT) and will be released during early May, 2002 into the Tucannon River (rkm 40-45). This will allow us to stay within our maximum allowed number (150,000) of smolts released. During April 2002, WDFW volitionally

  6. [Genetic Differentiation of Sockeye Salmon Oncorhynchus nerka from Kamchatka River Basin and the Lake-River Systems of the West Coast of the Bering Sea as Inferred from Data on Single Nucleotide Polymorphism].

    Science.gov (United States)

    Khrustaleva, A M; Klovach, N V; Vedischeva, E V; Seeb, J E

    2015-10-01

    The variability of 45 single nucleotide polymorphism loci (SNP) was studied in sockeye salmon from the Kamchatka River basin and four lake-river systems of the west coast of the Bering Sea. Based on the genetic differentiation estimates for the largest sockeye salmon populations of Eastern Kamchatka and Chukotka, the examined samples were combined into two regional groups represented by the population of the Kamchatka River drainage, which included numerous local subpopulations and seasonal races, and the northern population grouping from the rivers of Olutorsko-Navarinsky raion, wherein the sockeye salmon from Maynypilginskaya Lake-River system was relatively isolated. Considerable divergence was observed between the island (Sarannoe Lake, Bering Island) and continental populations. Genetic heterogeneity was revealed and groups of early- and late-maturing individuals were isolated in the sample of late-run sockeye salmon from Kamchatka River. In Apuka River, subdivision of the spawning run into two genetically distinct spatial and temporal groupings was also observed. The results suggest that the differentiation of sockeye salmon samples by single nucleotide substitution frequencies was largely due to differences in the direction and strength of local selection at some loci in the population complexes and intrapopulation groupings from the examined river basins of Eastern Kamchatka, Chukotka, and Commander Islands.

  7. Comparative phylogeography of the two pink salmon broodlines: an analysis based on a mitochondrial DNA genealogy.

    Science.gov (United States)

    Churikov, D; Gharrett, A J

    2002-06-01

    Over most of their natural northern Pacific Ocean range, pink salmon (Oncorhynchus gorbuscha) spawn in a habitat that was repeatedly and profoundly affected by Pleistocene glacial advances. A strictly two-year life cycle of pink salmon has resulted in two reproductively isolated broodlines, which spawn in alternating years and evolved as temporal replicates of the same species. To study the influence of historical events on phylogeographical and population genetic structure of the two broodlines, we first reconstructed a fine-scale mtDNA haplotype genealogy from a sample of 80 individuals and then determined the geographical distribution of the major genealogical assemblages for 718 individuals sampled from nine Alaskan and eastern Asian even- and nine odd-year pink salmon populations. Analysis of restriction site states in seven polymerase chain reaction (PCR)-amplified mtDNA regions (comprising 97% of the mitochondrial genome) using 13 endonucleases resolved 38 haplotypes, which clustered into five genealogical lineages that differed from 0.065 to 0.225% in net sequence divergence. The lineage sorting between broodlines was incomplete, which suggests a recent common ancestry. Within each lineage, haplotypes exhibited star-like genealogies indicating recent population growth. The depth of the haplotype genealogy is shallow ( approximately 0.5% of nucleotide sequence divergence) and probably reflects repeated decreases in population size due to Pleistocene glacial advances. Nested clade analysis (NCA) of geographical distances showed that the geographical distribution observed for mitochondrial DNA (mtDNA) haplotypes resulted from alternating influences of historical range expansions and episodes of restricted dispersal. Analyses of molecular variance showed weak geographical structuring of mtDNA variation, except for the strong subdivision between Asian and Alaskan populations within the even-year broodline. The genetic similarities observed among and within

  8. Breakup ice control structure for the Salmon River in Connecticut

    International Nuclear Information System (INIS)

    Tuthill, A.M.; White, K.D.

    1997-01-01

    The Salmon River ice jam problem was investigated and a conceptual design for a breakup ice control structure was developed. Historical ice jam events were reviewed and an ice observation program was conducted during the winter of 1994-95. The factors affecting ice jam frequency and severity were examined. The factors included daily temperature, rainfall quantity and intensity, Salmon River stage and discharge, and Connecticut River tide levels. First, a numerical model was developed to simulate a worst case scenario for ice jams, followed by a conceptual design for a concrete pier ice control structure under two ice breakup scenarios. The first scenario assumed that a semi-intact ice sheet would rest against the piers and retain a floating equilibrium jam upstream, allowing water discharge to pass beneath. The second scenario was based on the assumption that a grounded ice jam in direct contact with the piers would divert water flow around the structure via an armored channel in the overbank area. An ice retention structure consisting of a row of concrete piers, spaced across the main channel, 60 m upstream of an existing dam, was proposed. 11 refs., 6 figs

  9. Laboratory spawning of the purple snail Plicopurpura pansa (Gastropoda: Muricidae

    Directory of Open Access Journals (Sweden)

    Ludwig C. A. Naegel

    2004-03-01

    Full Text Available The spawning of the muricid gastropod Plicopurpura pansa in the laboratory at 22-23°C is described. Females deposited 1-20 capsules daily for at least 20 weeks, and produced up to 150 capsules each per spawning season. During spawning, egg clusters were formed consisting of hundreds of capsules of different ages deposited by different females. Each egg capsule contained an average of 436 embryos (± s.d. 213.6, range: 95- 1 092, n = 50. Embryos developed without nurse eggs. After six to eight weeks of intracapsular, lecithotrophic development, planktotrophic veligers hatched with two fully developed velar lobesSe describe el desove del gasterópodo Plicopurpura pansa (Gould, 1853 (Gastropoda, Prosobranchia, Muricidae a 22-23°C en el laboratorio. Cada hembra depositó diariamente de 1 a 20 cápsulas por lo menos durante 20 semanas y produjo hasta 150 cápsulas durante la estación de reproducción. Durante el tiempo de desove se formaron agrupaciones de cientos de cápsulas de diferentes edades y diferentes hembras. Cada cápsula contenía, según del tamaño, en promedio 436 embriones (± s.d. 213.6, ámbito: 95-1 092, n=50. Los embriones se desarrollaron sin huevos nutricios. Después de seis a ocho semanas del desarrollo lecitotrófico intracapsular eclosionaron larvas veliger planctotróficas completamente desarrolladas con dos velum de forma lobulada

  10. Carotenoid dynamics in Atlantic salmon

    Directory of Open Access Journals (Sweden)

    Omholt Stig W

    2006-04-01

    Full Text Available Abstract Background Carotenoids are pigment molecules produced mainly in plants and heavily exploited by a wide range of organisms higher up in the food-chain. The fundamental processes regulating how carotenoids are absorbed and metabolized in vertebrates are still not fully understood. We try to further this understanding here by presenting a dynamic ODE (ordinary differential equation model to describe and analyse the uptake, deposition, and utilization of a carotenoid at the whole-organism level. The model focuses on the pigment astaxanthin in Atlantic salmon because of the commercial importance of understanding carotenoid dynamics in this species, and because deposition of carotenoids in the flesh is likely to play an important life history role in anadromous salmonids. Results The model is capable of mimicking feed experiments analyzing astaxanthin uptake and retention over short and long time periods (hours, days and years under various conditions. A sensitivity analysis of the model provides information on where to look for possible genetic determinants underlying the observed phenotypic variation in muscle carotenoid retention. Finally, the model framework is used to predict that a specific regulatory system controlling the release of astaxanthin from the muscle is not likely to exist, and that the release of the pigment into the blood is instead caused by the androgen-initiated autolytic degradation of the muscle in the sexually mature salmon. Conclusion The results show that a dynamic model describing a complex trait can be instrumental in the early stages of a project trying to uncover underlying determinants. The model provides a heuristic basis for an experimental research programme, as well as defining a scaffold for modelling carotenoid dynamics in mammalian systems.

  11. The influence of population dynamics and environmental conditions on salmon re-colonization after large-scale distrubance

    Science.gov (United States)

    Pess, G. R.; Hilborn, R.; Kloehn, K.; Quinn, T.

    2010-12-01

    The transition from dispersal into unoccupied habitat to the establishment of a self-sustaining new population depends on the dynamics of the source and recipient populations, and the environmental conditions that facilitate or hinder exchange and successful reproduction. We used population growth rate, inter-annual variability estimates, habitat condition and size, hydrologic data, and an estimated dispersal effect to determine when colonizing pink salmon (Oncorhynchus gorbuscha) populations became self-sustaining after a long-term migration blockage (Hell’s Gate) was mitigated in the Fraser River, British Columbia, Canada. We used pink salmon spawning data from 1947 to 1987 in 66 streams to define populations, population growth rates, and the level of dispersal to newly accessible habitats. We also quantified the distance from source populations, the amount of newly accessible habitat, and determined whether stream flow conditions impeded fish passage at Hell’s Gate. Population dynamics models fit to observed data indicated that the combination of an initially large source population in the Fraser River below Hell’s Gate, high intrinsic growth rates linked to favorable climate-driven conditions, a constant supply of dispersers, and large amounts of newly available habitat resulted in the development of self-sustaining pink salmon populations in the Fraser River upstream of the historic barrier. Self-sustaining populations were developed within years of barrier removal and have continued to help expand the overall population of Fraser River pink salmon. However, not all locations had the same productivity and the magnitude of exchange among them was partly mediated by river conditions that permit or impede passage. Both re-colonized abundance levels were reduced and population spatial structure shifted relative to historic population abundance and spatial structure estimates.

  12. Multi-species spawning synchrony within scleractinian coral assemblages in the Red Sea

    KAUST Repository

    Bouwmeester, Jessica

    2014-09-21

    Early work on coral reproduction in the far northern Red Sea suggested that the spawning times of ecologically abundant species did not overlap, unlike on the Great Barrier Reef where many species spawn with high synchrony. In contrast, recent work in the northern and central Red Sea indicates a high degree of synchrony in the reproductive condition of Acropora species: over 90 % of species sampled in April/May contain mature gametes. However, it has yet to be determined when most Acropora release their gametes. In addition, there is a lack of data for other ecologically important scleractinian species such as merulinids and poritids. Here, we document the date and time of spawning for 51 species in the central Red Sea over three consecutive years, and the month of spawning for an additional 17 species inferred from the presence of mature gametes. Spawning occurs on nights around the full moon, the spawning season lasts at least 4 months from April until July, and observations are consistent with the few other records from the Red Sea. The number of Acropora species spawning was highest in April with 13 species spawning two nights before the full moon in 2011, 13 species spawning on the night of the full moon in 2012, and eight species spawning four nights after the full moon in 2013. The total number of species spawning was high in April, May, and June and involved 15–19 species per month in 2012. Only four species spawned in July 2012. Few regions worldwide have been similarly sampled and include the Philippines, Okinawa in Japan, and Palau, where spawning patterns are very similar to those in the central Red Sea and where corals spawn on nights around the full moon over a period of 3–4 months. In particular, in all four locations, Acropora are among the first species to spawn. Our results add to a growing body of evidence indicating that multi-species spawning synchrony is a feature of all speciose coral assemblages.

  13. Use of behavioral and physiological indicators to evaluate Scaphirhynchus sturgeon spawning success

    Science.gov (United States)

    DeLonay, A.J.; Papoulias, D.M.; Wildhaber, M.L.; Annis, M.L.; Bryan, J.L.; Griffith, S.A.; Holan, S.H.; Tillitt, D.E.

    2007-01-01

    Thirty gravid, female shovelnose sturgeon (Scaphirhynchus platorynchus) were captured in the Lower Missouri River in March 2004 to evaluate the effectiveness of physiology, telemetry and remote sensor technology coupled with change point analysis in identifying when and where Scaphirhynchus sturgeon spawn. Captured sturgeons were instrumented with ultrasonic transmitters and with archival data storage tags (DST) that recorded temperature and pressure. Female sturgeon were tracked through the suspected spawning period. Thereafter, attempts were made to recapture fish to evaluate spawning success. At the time of transmitter implantation, blood and an ovarian biopsy were taken. Reproductive hormones and cortisol were measured in blood. Polarization indices and germinal vesicle breakdown were assessed on the biopsied oocytes to determine readiness to spawn. Behavioral data collected using telemetry and DST sensors were used to determine the direction and magnitude of possible spawning-related movements and to identify the timing of potential spawning events. Upon recapture observations of the ovaries and blood chemistry provided measures of spawning success and comparative indicators to explain differences in observed behavior. Behavioral and physiological indicators of spawning interpreted along with environmental measures may assist in the determination of variables that may cue sturgeon reproduction and the conditions under which sturgeon successfully spawn.

  14. Bacterial acquisition in juveniles of several broadcast spawning coral species.

    Directory of Open Access Journals (Sweden)

    Koty H Sharp

    Full Text Available Coral animals harbor diverse microorganisms in their tissues, including archaea, bacteria, viruses, and zooxanthellae. The extent to which coral-bacterial associations are specific and the mechanisms for their maintenance across generations in the environment are unknown. The high diversity of bacteria in adult coral colonies has made it challenging to identify species-specific patterns. Localization of bacteria in gametes and larvae of corals presents an opportunity for determining when bacterial-coral associations are initiated and whether they are dynamic throughout early development. This study focuses on the early onset of bacterial associations in the mass spawning corals Montastraea annularis, M. franksi, M. faveolata, Acropora palmata, A. cervicornis, Diploria strigosa, and A. humilis. The presence of bacteria and timing of bacterial colonization was evaluated in gametes, swimming planulae, and newly settled polyps by fluorescence in situ hybridization (FISH using general eubacterial probes and laser-scanning confocal microscopy. The coral species investigated in this study do not appear to transmit bacteria via their gametes, and bacteria are not detectable in or on the corals until after settlement and metamorphosis. This study suggests that mass-spawning corals do not acquire, or are not colonized by, detectable numbers of bacteria until after larval settlement and development of the juvenile polyp. This timing lays the groundwork for developing and testing new hypotheses regarding general regulatory mechanisms that control bacterial colonization and infection of corals, and how interactions among bacteria and juvenile polyps influence the structure of bacterial assemblages in corals.

  15. Bacterial acquisition in juveniles of several broadcast spawning coral species.

    Science.gov (United States)

    Sharp, Koty H; Ritchie, Kim B; Schupp, Peter J; Ritson-Williams, Raphael; Paul, Valerie J

    2010-05-28

    Coral animals harbor diverse microorganisms in their tissues, including archaea, bacteria, viruses, and zooxanthellae. The extent to which coral-bacterial associations are specific and the mechanisms for their maintenance across generations in the environment are unknown. The high diversity of bacteria in adult coral colonies has made it challenging to identify species-specific patterns. Localization of bacteria in gametes and larvae of corals presents an opportunity for determining when bacterial-coral associations are initiated and whether they are dynamic throughout early development. This study focuses on the early onset of bacterial associations in the mass spawning corals Montastraea annularis, M. franksi, M. faveolata, Acropora palmata, A. cervicornis, Diploria strigosa, and A. humilis. The presence of bacteria and timing of bacterial colonization was evaluated in gametes, swimming planulae, and newly settled polyps by fluorescence in situ hybridization (FISH) using general eubacterial probes and laser-scanning confocal microscopy. The coral species investigated in this study do not appear to transmit bacteria via their gametes, and bacteria are not detectable in or on the corals until after settlement and metamorphosis. This study suggests that mass-spawning corals do not acquire, or are not colonized by, detectable numbers of bacteria until after larval settlement and development of the juvenile polyp. This timing lays the groundwork for developing and testing new hypotheses regarding general regulatory mechanisms that control bacterial colonization and infection of corals, and how interactions among bacteria and juvenile polyps influence the structure of bacterial assemblages in corals.

  16. Adhesion mechanism of salmon to polymer-coated can walls

    NARCIS (Netherlands)

    Dommershuijzen, H.; Hviid, L.; Hartog, den H.; Vereijken, J.

    2005-01-01

    Minimization of the amount of salmon adhering to the can wall after emptying is one of the convenience requirements of consumers of canned salmon. In order to achieve this, the mechanism by which salmon adheres to cans needs to be understood. The aim of this study was to provide such knowledge for

  17. Tucannon River Spring Chinook Salmon Captive Broodstock Program, Annual Report 2002.

    Energy Technology Data Exchange (ETDEWEB)

    Gallinat, Michael; Varney, Michelle

    2003-05-01

    This report summarizes the objectives, tasks, and accomplishments of the Tucannon River Spring Chinook Captive Broodstock Program during 2002. The WDFW initiated a captive broodstock program in 1997. The overall goal of the Tucannon River captive broodstock program is for the short-term, and eventually long-term, rebuilding of the Tucannon River spring chinook salmon run, with the hope that natural production will sustain itself. The project goal is to rear captive salmon selected from the supplementation program to adults, spawn them, rear their progeny, and release approximately 150,000 smolts annually into the Tucannon River between 2003-2007. These smolt releases, in combination with the current hatchery supplementation program (132,000 smolts) and wild production, are expected to produce 600-700 returning adult spring chinook to the Tucannon River each year from 2005-2010. The captive broodstock program collected fish from five (1997-2001) brood years (BY). As of January 1, 2003, WDFW has approximately 11 BY 1998, 194 BY 1999, 314 BY 2000, 447 BY 2001, and 300 BY 2002 (for extra males) fish on hand at LFH. The 2002 eggtake from the 1997 brood year (Age 5) was 13,176 eggs from 10 ripe females. Egg survival was 22%. Mean fecundity based on the 5 fully spawned females was 1,803 eggs/female. The 2002 eggtake from the 1998 brood year (Age 4) was 143,709 eggs from 93 ripe females. Egg survival was 29%. Mean fecundity based on the 81 fully spawned females was 1,650 eggs/female. The 2002 eggtake from the 1999 brood year (Age 3) was 19,659 eggs from 18 ripe females. Egg survival was 55%. Mean fecundity based on the 18 fully spawned fish was 1,092 eggs/female. The total 2002 eggtake from the captive brood program was 176,544 eggs. A total of 120,833 dead eggs (68%) were removed with 55,711 live eggs remaining for the program. As of May 1, 2003 we had 46,417 BY 2002 captive brood progeny on hand A total of 20,592 excess BY 01 fish were marked as parr (AD/CWT) and

  18. Baseline ecological risk assessment Salmon Site, Lamar County, Mississippi

    International Nuclear Information System (INIS)

    1995-04-01

    The Salmon Site (SS), formerly the Tatum Dome Test Site, located in Mississippi was the site of two nuclear and two gas explosion tests conducted between 1964 and 1970. A consequence of these testing activities is that radionuclides were released into the salt dome, where they are presently contained. During reentry drilling and other site activities, incidental liquid and solid wastes that contained radioactivity were generated, resulting in some soil, ground water and equipment contamination. As part of the remedial investigation effort, a Baseline Ecological Risk Assessment was conducted at the SS. The purpose is to gauge ecological and other environmental impacts attributable to past activities at the former test facility. The results of this facility-specific baseline risk assessment are presented in this document

  19. Baseline ecological risk assessment Salmon Site, Lamar County, Mississippi

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-04-01

    The Salmon Site (SS), formerly the Tatum Dome Test Site, located in Mississippi was the site of two nuclear and two gas explosion tests conducted between 1964 and 1970. A consequence of these testing activities is that radionuclides were released into the salt dome, where they are presently contained. During reentry drilling and other site activities, incidental liquid and solid wastes that contained radioactivity were generated, resulting in some soil, ground water and equipment contamination. As part of the remedial investigation effort, a Baseline Ecological Risk Assessment was conducted at the SS. The purpose is to gauge ecological and other environmental impacts attributable to past activities at the former test facility. The results of this facility-specific baseline risk assessment are presented in this document.

  20. Sea Louse Infection of Juvenile Sockeye Salmon in Relation to Marine Salmon Farms on Canada's West Coast

    OpenAIRE

    Routledge, Rick; Price, Michael; Proboszcz, Stan; Gottesfeld, Allen; Orr, Craig; Reynolds, John

    2011-01-01

    BACKGROUND: Pathogens are growing threats to wildlife. The rapid growth of marine salmon farms over the past two decades has increased host abundance for pathogenic sea lice in coastal waters, and wild juvenile salmon swimming past farms are frequently infected with lice. Here we report the first investigation of the potential role of salmon farms in transmitting sea lice to juvenile sockeye salmon (Oncorhynchus nerka). METHODOLOGY/PRINCIPAL FINDINGS: We used genetic analyses to determine the...

  1. Restitution and genetic differentiation of salmon populations in the southern Baltic genotyped with the Atlantic salmon 7K SNP array

    OpenAIRE

    Poćwierz-Kotus, Anita; Bernaś, Rafał; Kent, Matthew Peter; Lien, Sigbjørn; Leliüna, Egidijus; Dębowski, Piotr; Wenne, Roman

    2015-01-01

    Background Native populations of Atlantic salmon in Poland, from the southern Baltic region, became extinct in the 1980s. Attempts to restitute salmon populations in Poland have been based on a Latvian salmon population from the Daugava river. Releases of hatchery reared smolts started in 1986, but to date, only one population with confirmed natural reproduction has been observed in the Slupia river. Our aim was to investigate the genetic differentiation of salmon populations in the southern ...

  2. Mixed evidence for reduced local adaptation in wild salmon resulting from interbreeding with escaped farmed salmon: complexities in hybrid fitness

    OpenAIRE

    Fraser, Dylan J; Cook, Adam M; Eddington, James D; Bentzen, Paul; Hutchings, Jeffrey A

    2008-01-01

    Interbreeding between artificially-selected and wild organisms can have negative fitness consequences for the latter. In the Northwest Atlantic, farmed Atlantic salmon recurrently escape into the wild and enter rivers where small, declining populations of wild salmon breed. Most farmed salmon in the region derive from an ancestral source population that occupies a nonacidified river (pH 6.0–6.5). Yet many wild populations with which escaped farmed salmon might interbreed inhabit acidified riv...

  3. Skip spawning as a reproductive strategy in Antarctic fish species: the Antarctic silverfish (Pleuragramma antarctica case study

    Directory of Open Access Journals (Sweden)

    Eva Pisano

    2015-11-01

    Full Text Available The Antarctic silverfish Pleuragramma antarctica (Notothenioidei, Nototheniidae is the most abundant pelagic fish inhabiting the frigid Antarctic coastal waters. It plays relevant roles in the local ecosystems, where it is often considered a keystone species connecting lower and upper trophic levels within the coastal marine food web. Despite its ecological relevance, and although many aspects of the Antarctic silverfish biology have already been elucidated, knowledge on important components of its life cycle, including the reproductive features, is still poor. The available data on the reproduction of the Antarctic silverfish remains fragmentary and, in particular, information on the silverfish from the Ross Sea is lacking, in spite of the intensive ecological studies on this unique region and the fact that the only known nursery ground for this species is located in Terra Nova Bay (Ross Sea where hatching occurs under the sea-ice. We present the here first description of the reproductive features of Antarctic silverfish from fish sampled in late Summer (mid February 2008 in the Ross Sea. The gross reproductive traits are consistent with those reported from other Antarctic sectors but, interestingly, widespread follicular atresia has been detected in the fish examined. The intensity and prevalence of such a follicular degenerative process suggest that skip spawning (not all adults spawn every year could be a reproductive strategy of this Antarctic species. Such an hypothesis is discussed both on the short-term and on the evolutionary time-scale. Overall, the data presented also contribute to support the acknowledgment that skip-spawning is a diffuse phenomenon in fishes.

  4. Instream flow characterization of Upper Salmon River basin streams, central Idaho, 2005

    Science.gov (United States)

    Maret, Terry R.; Hortness, Jon E.; Ott, Douglas S.

    2006-01-01

    Anadromous fish populations in the Columbia River Basin have plummeted in the last 100 years. This severe decline led to Federal listing of Chinook salmon (Oncorhynchus tshawytscha) and steelhead trout (Oncorhynchus mykiss) stocks as endangered or threatened under the Endangered Species Act (ESA) in the 1990s. Historically, the upper Salmon River Basin (upstream of the confluence with the Pahsimeroi River) in Idaho provided migration corridors and significant habitat for these ESA-listed species, in addition to the ESA-listed bull trout (Salvelinus confluentus). Human development has modified the original streamflow conditions in many streams in the upper Salmon River Basin. Summer streamflow modifications resulting from irrigation practices, have directly affected quantity and quality of fish habitat and also have affected migration and (or) access to suitable spawning and rearing habitat for these fish. As a result of these ESA listings and Action 149 of the Federal Columbia River Power System Biological Opinion of 2000, the Bureau of Reclamation was tasked to conduct streamflow characterization studies in the upper Salmon River Basin to clearly define habitat requirements for effective species management and habitat restoration. These studies include collection of habitat and streamflow information for the Physical Habitat Simulation System (PHABSIM) model, a widely applied method to determine relations between habitat and discharge requirements for various fish species and life stages. Model simulation results can be used by resource managers to guide habitat restoration efforts by evaluating potential fish habitat and passage improvements by increasing or decreasing streamflow. In 2005, instream flow characterization studies were completed on Big Boulder, Challis, Bear, Mill, and Morgan Creeks. Continuous streamflow data were recorded upstream of all diversions on Big Boulder. Instantaneous measurements of discharge were also made at selected sites. In

  5. Passive acoustic monitoring to detect spawning in large-bodied catostomids

    Science.gov (United States)

    Straight, Carrie A.; Freeman, Byron J.; Freeman, Mary C.

    2014-01-01

    Documenting timing, locations, and intensity of spawning can provide valuable information for conservation and management of imperiled fishes. However, deep, turbid or turbulent water, or occurrence of spawning at night, can severely limit direct observations. We have developed and tested the use of passive acoustics to detect distinctive acoustic signatures associated with spawning events of two large-bodied catostomid species (River Redhorse Moxostoma carinatum and Robust Redhorse Moxostoma robustum) in river systems in north Georgia. We deployed a hydrophone with a recording unit at four different locations on four different dates when we could both record and observe spawning activity. Recordings captured 494 spawning events that we acoustically characterized using dominant frequency, 95% frequency, relative power, and duration. We similarly characterized 46 randomly selected ambient river noises. Dominant frequency did not differ between redhorse species and ranged from 172.3 to 14,987.1 Hz. Duration of spawning events ranged from 0.65 to 11.07 s, River Redhorse having longer durations than Robust Redhorse. Observed spawning events had significantly higher dominant and 95% frequencies than ambient river noises. We additionally tested software designed to automate acoustic detection. The automated detection configurations correctly identified 80–82% of known spawning events, and falsely indentified spawns 6–7% of the time when none occurred. These rates were combined over all recordings; rates were more variable among individual recordings. Longer spawning events were more likely to be detected. Combined with sufficient visual observations to ascertain species identities and to estimate detection error rates, passive acoustic recording provides a useful tool to study spawning frequency of large-bodied fishes that displace gravel during egg deposition, including several species of imperiled catostomids.

  6. Temporal patterns of migration and spawning of river herring in coastal Massachusetts

    Science.gov (United States)

    Rosset, Julianne; Roy, Allison; Gahagan, Benjamin I.; Whiteley, Andrew R.; Armstrong, Michael P.; Sheppard, John J.; Jordaan, Adrian

    2017-01-01

    Migrations of springtime Alewife Alosa pseudoharengus and Blueback Herring A. aestivalis, collectively referred to as river herring, are monitored in many rivers along the Atlantic coast to estimate population sizes. While these estimates give an indication of annual differences in the number of returning adults, links to the subsequent timing and duration of spawning and freshwater juvenile productivity remain equivocal. In this study, we captured juvenile river herring at night in 20 coastal Massachusetts lakes using a purse seine and extracted otoliths to derive daily fish ages and back-calculate spawn dates. Estimates of spawning dates were compared with fishway counts of migrating adults to assess differences in migration timing and the timing and duration of spawning. We observed a distinct delay between the beginning of the adult migration run and the start of spawning, ranging from 7 to 28 d across the 20 lakes. Spawning continued 13–48 d after adults stopped migrating into freshwater, further demonstrating a pronounced delay in spawning following migration. Across the study sites the duration of spawning (43–76 d) was longer but not related to the duration of migration (29–66 d). The extended spawning period is consistent with recent studies suggesting that Alewives are indeterminate spawners. The long duration in freshwater provides the opportunity for top-down (i.e., predation on zooplankton) and bottom-up (i.e., food for avian, fish, and other predators) effects, with implications for freshwater food webs and nutrient cycling. General patterns of spawn timing and duration can be incorporated into population models and used to estimate temporal changes in productivity associated with variable timing and density of spawning river herring in lakes.

  7. Primary and secondary sexual characters in alternative reproductive tactics of Chinook salmon: Associations with androgens and the maturation-inducing steroid.

    Science.gov (United States)

    Butts, Ian A E; Love, Oliver P; Farwell, Michelle; Pitcher, Trevor E

    2012-02-01

    The proximate mechanisms that underlie the evolution of within-sex variation in mating behavior, sexual characters and reproductive investment patterns are still poorly understood. Species exhibiting alternative reproductive tactics (ARTs) are ideal model systems to examine these mechanisms. Chinook salmon (Oncorhynchus tshawytscha) exhibits two distinct ARTs: hooknoses, which are large males that establish spawning dominance hierarchies via intense male-male competition and jacks, which are smaller precocious sneaking males that steal fertilizations via sperm competition. In this study, we examine plasma testosterone (T), 11-ketotestosterone (11-KT) and maturation-inducing steroid (MIS; 17α,20β-dihydroxy-4-pregnen-3-one) profiles of spawning hooknoses and jacks. Furthermore, we examine relationships between androgens and primary (gonad mass, gonadosomatic index and sperm traits) and secondary (total mass, body size, hump depth and kype length) sexual characters. Relationships between MIS and sperm traits are also examined. We found that hooknoses and jacks did not significantly differ in terms of plasma T, 11-KT or MIS concentrations. Moreover, we found significant positive relationships between levels of both androgens within each ART. There were no significant relationships between androgens, MIS and sperm traits. T and 11-KT concentrations co-varied positively with gonad investment and kype length in jacks. In hooknoses, 11-KT concentration was positively related to total mass, hump depth and condition factor. Overall, these findings suggest that there are differential androgen effects for each of the ARTs in Chinook salmon. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

  8. The effect of chronic chromium exposure on the health of Chinook salmon (Oncorhynchus tshawytscha)

    Science.gov (United States)

    Farag, A.M.; May, T.; Marty, G.D.; Easton, M.; Harper, D.D.; Little, E.E.; Cleveland, L.

    2006-01-01

    This study was designed to determine fish health impairment of Chinook salmon (Oncorhynchus tshawytscha) exposed to chromium. Juvenile Chinook salmon were exposed to aqueous chromium concentrations (0–266 μg l−1) that have been documented in porewater from bottom sediments and in well waters near salmon spawning areas in the Columbia River in the northwestern United States. After Chinook salmon parr were exposed to 24 and 54 μg Cr l−1 for 105 days, neither growth nor survival of parr was affected. On day 105, concentrations were increased from 24 to 120 μg Cr l−1and from 54 to 266 μg Cr l−1 until the end of the experiment on day 134. Weight of parr was decreased in the 24/120 μg Cr l−1 treatment, and survival was decreased in the 54/266 μg Cr l−1 treatment. Fish health was significantly impaired in both the 24/120 and 54/266 μg Cr l−1 treatments. The kidney is the target organ during chromium exposures through the water column. The kidneys of fish exposed to the greatest concentrations of chromium had gross and microscopic lesions (e.g. necrosis of cells lining kidney tububules) and products of lipid peroxidation were elevated. These changes were associated with elevated concentrations of chromium in the kidney, and reduced growth and survival. Also, variations in DNA in the blood were associated with pathological changes in the kidney and spleen. These changes suggest that chromium accumulates and enters the lipid peroxidation pathway where fatty acid damage and DNA damage (expressed as chromosome changes) occur to cause cell death and tissue damage. While most of the physiological malfunctions occurred following parr exposures to concentrations ≥120 μg Cr l−1, nuclear DNA damage followed exposures to 24 μg Cr l−1, which was the smallest concentration tested. The abnormalities measured during this study are particularly important because they are associated with impaired growth and reduced survival at

  9. Effects of frequency of egg and fry removal on spawning by Tilapia nilotica in hapas

    NARCIS (Netherlands)

    Verdegem, M.C.J.; McGinty, A.S.

    1987-01-01

    Tilapia nilotica were spawned in small-mesh net enclosures called hapas. During a 5-week period, eggs and fry were removed from mouth-brooding females at examination intervals of 2, 4, 7, or 10 d. A decrease in time between examination intervals increased the total number of spawns collected (P

  10. Influence of Color of Polythene Container and three Spawn rates on ...

    African Journals Online (AJOL)

    a

    2012-04-16

    Apr 16, 2012 ... yield was obtained in green colour polythene (1366 g/2 kg wet substrate). The least of yield mushrooms were obtained from 2.5 % spawn rate and cultivation of mushroom in blue polythene container. It was concluded that the mushroom should be cultivated in green polythene bags under 5% spawn rate to.

  11. Spawning strategies and transport of early stages of the two Cape ...

    African Journals Online (AJOL)

    Seasonal and short-term variability of environmental parameters influence the spawning strategies of fish species. In this study, the spawning strategies and the transport of early stages of the two Cape hake species off South Africa were investigated. Distribution of eggs and larvae of Merluccius paradoxus and M. capensis ...

  12. Estimating spawning habitat availability in flooded areas of the river Waal, the Netherlands

    NARCIS (Netherlands)

    Wolfshaar, van de K.E.; Ruizeveld de Winter, A.C.; Straatsma, M.W.; Brink, N.G.M.; Leeuw, de J.J.

    2010-01-01

    Fish spawning habitat availability in the river Waal is significantly influenced by seasonal and annual variations in discharge. In this paper we develop habitat suitability models, based on a literature survey of spawning preferences of the commonly occurring species roach (Rutilus rutilus), bream

  13. Fall spawning of Atlantic sturgeon in the Roanoke River, North Carolina

    Science.gov (United States)

    Smith, Joseph A.; Hightower, Joseph E.; Flowers, H. Jared

    2015-01-01

    In 2012, the National Oceanic and Atmospheric Administration (NOAA) declared Atlantic Sturgeon Acipenser oxyrinchus oxyrinchus to be threatened or endangered throughout its range in U.S. waters. Restoration of the subspecies will require much new information, particularly on the location and timing of spawning. We used a combination of acoustic telemetry and sampling with anchored artificial substrates (spawning pads) to detect fall (September–November) spawning in the Roanoke River in North Carolina. This population is included in the Carolina Distinct Population Segment, which was classified by NOAA as endangered. Sampling was done immediately below the first shoals encountered by anadromous fishes, near Weldon. Our collection of 38 eggs during the 21 d that spawning pads were deployed appears to be the first such collection (spring or fall) for wild-spawned Atlantic Sturgeon eggs. Based on egg development stages, estimated spawning dates were September 17–18 and 18–19 at water temperatures from 25.3°C to 24.3°C and river discharge from 55 to 297 m3/s. These observations about fall spawning and habitat use should aid in protecting critical habitats and planning research on Atlantic Sturgeon spawning in other rivers.

  14. Evidence of sound production by spawning lake trout (Salvelinus namaycush) in lakes Huron and Champlain

    Science.gov (United States)

    Johnson, Nicholas S.; Higgs, Dennis; Binder, Thomas R.; Marsden, J. Ellen; Buchinger, Tyler John; Brege, Linnea; Bruning, Tyler; Farha, Steve A.; Krueger, Charles C.

    2018-01-01

    Two sounds associated with spawning lake trout (Salvelinus namaycush) in lakes Huron and Champlain were characterized by comparing sound recordings to behavioral data collected using acoustic telemetry and video. These sounds were named growls and snaps, and were heard on lake trout spawning reefs, but not on a non-spawning reef, and were more common at night than during the day. Growls also occurred more often during the spawning period than the pre-spawning period, while the trend for snaps was reversed. In a laboratory flume, sounds occurred when male lake trout were displaying spawning behaviors; growls when males were quivering and parallel swimming, and snaps when males moved their jaw. Combining our results with the observation of possible sound production by spawning splake (Salvelinus fontinalis × Salvelinus namaycush hybrid), provides rare evidence for spawning-related sound production by a salmonid, or any other fish in the superorder Protacanthopterygii. Further characterization of these sounds could be useful for lake trout assessment, restoration, and control.

  15. Gametogenic development and spawning of the mud clam, Polymesoda erosa (Solander, 1876) at Chorao Island, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Clemente, S.; Ingole, B.S.

    to 4.7 in March, with low values during the spawning period. The clams attained their best condition in quality of flesh weight during March-May. The data presented here should provide valuable information on the timing of spawning events for P. erosa...

  16. Salmon: Robust Proxy Distribution for Censorship Circumvention

    Directory of Open Access Journals (Sweden)

    Douglas Frederick

    2016-10-01

    Full Text Available Many governments block their citizens’ access to much of the Internet. Simple workarounds are unreliable; censors quickly discover and patch them. Previously proposed robust approaches either have non-trivial obstacles to deployment, or rely on low-performance covert channels that cannot support typical Internet usage such as streaming video. We present Salmon, an incrementally deployable system designed to resist a censor with the resources of the “Great Firewall” of China. Salmon relies on a network of volunteers in uncensored countries to run proxy servers. Although any member of the public can become a user, Salmon protects the bulk of its servers from being discovered and blocked by the censor via an algorithm for quickly identifying malicious users. The algorithm entails identifying some users as especially trustworthy or suspicious, based on their actions. We impede Sybil attacks by requiring either an unobtrusive check of a social network account, or a referral from a trustworthy user.

  17. Research, monitoring, and evaluation of emerging issues and measures to recover the Snake River fall Chinook salmon ESU, 1/1/2014 - 12/31/2014

    Science.gov (United States)

    Connor, William P.; Mullins, Frank L.; Tiffan, Kenneth F.; Perry, Russell W.; Erhardt, John M.; St John, Scott J.; Bickford, Brad; Rhodes, Tobyn N.

    2015-01-01

    The portion of the Snake River fall Chinook Salmon Oncorhynchus tshawytscha ESU that spawns upstream of Lower Granite Dam transitioned from low to high abundance during 1992–2014 in association with U.S. Endangered Species Act recovery efforts and other Federally mandated actions. This annual report focuses on (1) numeric and habitat use responses by natural- and hatchery-origin spawners, (2) phenotypic and numeric responses by natural-origin juveniles, and (3) predator responses in the Snake River upper and lower reaches as abundance of adult and juvenile fall Chinook Salmon increased. Spawners have located and used most of the available spawning habitat and that habitat is gradually approaching redd capacity. Timing of spawning and fry emergence has been relatively stable; whereas the timing of parr dispersal from riverine rearing habitat into Lower Granite Reservoir has become earlier as apparent abundance of juveniles has increased. Growth rate (g/d) and dispersal size of parr also declined as apparent abundance of juveniles increased. Passage timing of smolts from the two Snake River reaches has become earlier and downstream movement rate faster as estimated abundance of fall Chinook Salmon smolts in Lower Granite Reservoir has increased. In 2014, consumption of subyearlings by Smallmouth Bass was highest in the upper reach which had the highest abundance of Bass. With a few exceptions, predation tended to decrease seasonally from April through early July. A release of hatchery fish in mid-May significantly increased subyearling consumption by the following day. We estimated that over 600,000 subyearling fall Chinook Salmon were lost to Smallmouth Bass predation along the free-flowing Snake River in 2014. More information on predation is presented in Appendix A.3 (page 51). These findings coupled with stock-recruitment analyses presented in this report provide evidence for density-dependence in the Snake River reaches and in Lower Granite Reservoir that was

  18. Characteristics of the Norwegian Coastal Current during Years with High Recruitment of Norwegian Spring Spawning Herring (Clupea harengus L..

    Directory of Open Access Journals (Sweden)

    Øystein Skagseth

    Full Text Available Norwegian Spring Spawning herring (NSSH Clupea harengus L. spawn on coastal banks along the west coast of Norway. The larvae are generally transported northward in the Norwegian Coastal Current (NCC with many individuals utilizing nursery grounds in the Barents Sea. The recruitment to this stock is highly variable with a few years having exceptionally good recruitment. The principal causes of recruitment variability of this herring population have been elusive. Here we undertake an event analysis using data between 1948 and 2010 to gain insight into the physical conditions in the NCC that coincide with years of high recruitment. In contrast to a typical year when northerly upwelling winds are prominent during spring, the years with high recruitment coincide with predominantly southwesterly winds and weak upwelling in spring and summer, which lead to an enhanced northward coastal current during the larval drift period. Also in most peak recruitment years, low-salinity anomalies are observed to propagate northward during the spring and summer. It is suggested that consistent southwesterly (downwelling winds and propagating low-salinity anomalies, both leading to an enhanced northward transport of larvae, are important factors for elevated recruitment. At the same time, these conditions stabilize the coastal waters, possibly leading to enhanced production and improved feeding potential along the drift route to Barents Sea. Further studies on the drivers of early life history mortality can now be undertaken with a better understanding of the physical conditions that prevail during years when elevated recruitment occurs in this herring stock.

  19. Asynchronous behavior of the Antarctic Ice Sheet and local glaciers during and since Termination 1, Salmon Valley, Antarctica

    Science.gov (United States)

    Jackson, Margaret S.; Hall, Brenda L.; Denton, George H.

    2018-01-01

    The stability of the Antarctic Ice Sheet under future warming remains an open question with broad implications for sea-level prediction and adaptation. In particular, knowledge of whether the ice sheet has the capacity for rapid drawdown or collapse, or whether it can remain stable during periods of warming, is essential for predicting its future behavior. Here we use 55 radiocarbon dates, coupled with geomorphologic mapping, to reconstruct the timing of changes in ice extent and elevation during the last ice-age termination in Salmon Valley, adjacent to McMurdo Sound in the western Ross Sea Embayment. Results indicate that a grounded ice sheet in the Ross Sea Embayment achieved its maximum elevation and extent along the headlands of Salmon Valley at ∼18,000 yr BP, during a period of increasing temperatures and accumulation over the Antarctic continent. This ice remained at or near its maximum on the headlands near the valley mouth until after ∼14,000 yr BP. Removal of grounded Ross Sea ice from Salmon Valley was complete shortly after ∼7900 yr BP, indicating that the grounding line had retreated through southern McMurdo Sound by that time. We suggest the primary driver of Ross Sea ice removal from McMurdo Sound was marine-based, either through basal melting or calving due to sea-level rise. When combined with regional data, the Salmon Valley record suggests that this sector of the Antarctic Ice Sheet did not contribute in a significant way to deglacial meltwater pulses, such as meltwater pulse 1a. In contrast to the Ross Sea ice, our work also shows that local, independent alpine glaciers in Salmon Valley have advanced through the Holocene. Land-terminating glaciers such as these elsewhere in the region show a similar pattern, and may reflect the continued influence of increased accumulation following the termination of the last ice age.

  20. Cessation of a salmon decline with control of parasites

    KAUST Repository

    Peacock, Stephanie J.

    2013-04-01

    The resilience of coastal social-ecological systems may depend on adaptive responses to aquaculture disease outbreaks that can threaten wild and farm fish. A nine-year study of parasitic sea lice (Lepeophtheirus salmonis) and pink salmon (Oncorhynchus gorbuscha) from Pacific Canada indicates that adaptive changes in parasite management on salmon farms have yielded positive conservation outcomes. After four years of sea lice epizootics and wild salmon population decline, parasiticide application on salmon farms was adapted to the timing of wild salmon migrations. Winter treatment of farm fish with parasiticides, prior to the out-migration of wild juvenile salmon, has reduced epizootics of wild salmon without significantly increasing the annual number of treatments. Levels of parasites on wild juvenile salmon significantly influence the growth rate of affected salmon populations, suggesting that these changes in management have had positive outcomes for wild salmon populations. These adaptive changes have not occurred through formal adaptive management, but rather, through multi-stakeholder processes arising from a contentious scientific and public debate. Despite the apparent success of parasite control on salmon farms in the study region, there remain concerns about the long-term sustainability of this approach because of the unknown ecological effects of parasticides and the potential for parasite resistance to chemical treatments. © 2013 by the Ecological Society of America.

  1. Historical spatial reconstruction of a spawning-aggregation fishery.

    Science.gov (United States)

    Buckley, Sarah M; Thurstan, Ruth H; Tobin, Andrew; Pandolfi, John M

    2017-12-01

    Aggregations of individual animals that form for breeding purposes are a critical ecological process for many species, yet these aggregations are inherently vulnerable to exploitation. Studies of the decline of exploited populations that form breeding aggregations tend to focus on catch rate and thus often overlook reductions in geographic range. We tested the hypothesis that catch rate and site occupancy of exploited fish-spawning aggregations (FSAs) decline in synchrony over time. We used the Spanish mackerel (Scomberomorus commerson) spawning-aggregation fishery in the Great Barrier Reef as a case study. Data were compiled from historical newspaper archives, fisher knowledge, and contemporary fishery logbooks to reconstruct catch rates and exploitation trends from the inception of the fishery. Our fine-scale analysis of catch and effort data spanned 103 years (1911-2013) and revealed a spatial expansion of fishing effort. Effort shifted offshore at a rate of 9.4 nm/decade, and 2.9 newly targeted FSAs were reported/decade. Spatial expansion of effort masked the sequential exploitation, commercial extinction, and loss of 70% of exploited FSAs. After standardizing for improvements in technological innovations, average catch rates declined by 90.5% from 1934 to 2011 (from 119.4 to 11.41 fish/vessel/trip). Mean catch rate of Spanish mackerel and occupancy of exploited mackerel FSAs were not significantly related. Our study revealed a special kind of shifting spatial baseline in which a contraction in exploited FSAs occurred undetected. Knowledge of temporally and spatially explicit information on FSAs can be relevant for the conservation and management of FSA species. © 2017 Society for Conservation Biology.

  2. Gamete plasticity in a broadcast spawning marine invertebrate.

    Science.gov (United States)

    Crean, Angela J; Marshall, Dustin J

    2008-09-09

    Sperm competition has classically been thought to maintain anisogamy (large eggs and smaller sperm) because males are thought to maximize their chance of winning fertilizations by trading sperm size for number. More recently it has been recognized that sperm quality (e.g., size, velocity) can also influence sperm competition, although studies have yielded conflicting results. Because sex evolved in the sea, debate has continued over the role of sperm competition and sperm environment in determining both sperm and egg size in externally fertilizing broadcast spawners. Remarkably, however, there have been no direct tests of whether broadcast spawners change the traits of their gametes depending on the likelihood of sperm competition. We manipulated the density (and thus, sperm environment) of a broadcast spawning ascidian (Styela plicata) in the field and then determined whether the phenotype of eggs and sperm changed. We found that sperm from adults kept at high density were larger and more motile than sperm from low-density adults. In vitro fertilizations revealed that sperm from high-density adults also lived longer and induced less polyspermy. Adult density also affected egg traits: eggs from high-density adults were smaller targets for sperm overall but produced larger ovicells than eggs from low-density adults. This suggests that broadcast spawning mothers balance (potentially conflicting) pre- and postzygotic selection pressures on egg size. Overall, our results suggest that sperm competition does not represent a strong force maintaining anisogamy in broadcast spawners. Instead, sperm limitation seems to select for large eggs and smaller, more numerous sperm.

  3. Characterizing and predicting the distribution of Baltic Sea flounder (Platichthys flesus) during the spawning season

    DEFF Research Database (Denmark)

    Orio, Alessandro; Bergström, Ulf; Casini, Michele

    2017-01-01

    Identification of essential fish habitats (EFH), such as spawning habitats, is important for nature conservation, sustainable fisheries management and marine spatial planning. Two sympatric flounder (Platichthys flesus) ecotypes are present in the Baltic Sea, pelagic and demersal spawning flounde...

  4. Preliminary evaluation of the behavior and movements of adult spring Chinook salmon in the Chehalis River, southwestern Washington, 2014

    Science.gov (United States)

    Liedtke, Theresa L.; Hurst, William R.; Tomka, Ryan G.; Kock, Tobias J.; Zimmerman, Mara S.

    2017-01-30

    Recent interest in flood control and restoration strategies in the Chehalis River Basin has increased the need to understand the current status and ecology of spring Chinook salmon (Oncorhynchus tshawytscha). Spring Chinook salmon have the longest exposure of all adult Chinook salmon life histories to the low-flow and high water temperature conditions that typically occur during summer. About 100 adult spring Chinook salmon were found dead in the Chehalis River in July and August 2009. Adult Chinook salmon are known to hold in cool-water refugia during warm summer months, but the extent to which spring Chinook salmon might use thermal refugia in the Chehalis River is unknown. A preliminary evaluation of the movements and temperature exposures of adult spring Chinook salmon following their return to the Chehalis River was conducted using radiotelemetry and transmitters equipped with temperature sensors. A total of 12 spring Chinook salmon were captured, radio-tagged, and released in the main-stem Chehalis River between May and late June 2014. Tagged fish were monitored from freshwater entry through the spawning period using a combination of fixedsite monitoring locations and mobile tracking.Water temperature and flow conditions in the main-stem Chehalis River during 2014 were atypical compared to historical averages. Mean monthly water temperatures between March and August 2014 were higher than any decade since 1960 and mean monthly discharge was 90–206 percent of the discharge in previous years. Overall, 92 percent of the tagged fish were detected, with a mean of 102 d in the detection history of tagged fish. Seven tagged fish (58 percent) moved upstream, either shortly after release (5–8 d, 57 percent), or within about a month (34–35 d, 29 percent). One fish (14 percent) remained near the release location for 98 d before moving upstream. The final fates for the seven fish that moved upstream following release included six fish that were assigned a fate of

  5. Chinook salmon Genetic Stock Identification data - Genetic Stock Identification of Washington Chinook salmon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project evaluates data from coded wire tagging with that from parental based tagging to identify stock of origin for Chinook salmon landed in Washington state...

  6. Salmon and steelhead genetics and genomics - Epigenetic and genomic variation in salmon and steelhead

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Conduct analyses of epigenetic and genomic variation in Chinook salmon and steelhead to determine influence on phenotypic expression of life history traits. Genetic,...

  7. Chum and pink salmon genetics - Genetic and life history variation of southern chum and pink salmon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The distribution of genetic and life history variation in chum (Oncorhynchus keta) and pink (O. gorbuscha) salmon in their southern range in North America is key to...

  8. Not all salmon are created equal: life cycle assessment (LCA) of global salmon farming systems.

    Science.gov (United States)

    Pelletier, Nathan; Tyedmers, Peter; Sonesson, Ulf; Scholz, Astrid; Ziegler, Friederike; Flysjo, Anna; Kruse, Sarah; Cancino, Beatriz; Silverman, Howard

    2009-12-01

    We present a global-scale life cycle assessment of a major food commodity, farmed salmon. Specifically, we report the cumulative energy use, biotic resource use, and greenhouse gas, acidifying, and eutrophying emissions associated with producing farmed salmon in Norway, the UK, British Columbia (Canada), and Chile, as well as a production-weighted global average. We found marked differences in the nature and quantity of material/energy resource use and associated emissions per unit production across regions. This suggests significant scope for improved environmental performance in the industry as a whole. We identify key leverage points for improving performance, most notably the critical importance of least-environmental cost feed sourcing patterns and continued improvements in feed conversion efficiency. Overall, impacts were lowest for Norwegian production in most impact categories, and highest for UK farmed salmon. Our results are of direct relevance to industry, policy makers, eco-labeling programs, and consumers seeking to further sustainability objectives in salmon aquaculture.

  9. Salmon vulnerability maps - Effect of Climate Change on Salmon Population Vulnerability

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Steelhead (Oncorhynchus mykiss) and other Pacific salmon are threatened by unsustainable levels of harvest, genetic introgression from hatchery stocks and...

  10. Migratory Patterns of Wild Chinook Salmon Oncorhynchus tshawytscha Returning to a Large, Free-Flowing River Basin.

    Directory of Open Access Journals (Sweden)

    John H Eiler

    Full Text Available Upriver movements were determined for Chinook salmon Oncorhynchus tshawytscha returning to the Yukon River, a large, virtually pristine river basin. These returns have declined dramatically since the late 1990s, and information is needed to better manage the run and facilitate conservation efforts. A total of 2,860 fish were radio tagged during 2002-2004. Most (97.5% of the fish tracked upriver to spawning areas displayed continual upriver movements and strong fidelity to the terminal tributaries entered. Movement rates were substantially slower for fish spawning in lower river tributaries (28-40 km d-1 compared to upper basin stocks (52-62 km d-1. Three distinct migratory patterns were observed, including a gradual decline, pronounced decline, and substantial increase in movement rate as the fish moved upriver. Stocks destined for the same region exhibited similar migratory patterns. Individual fish within a stock showed substantial variation, but tended to reflect the regional pattern. Differences between consistently faster and slower fish explained 74% of the within-stock variation, whereas relative shifts in sequential movement rates between "hares" (faster fish becoming slower and "tortoises" (slow but steady fish explained 22% of the variation. Pulses of fish moving upriver were not cohesive. Fish tagged over a 4-day period took 16 days to pass a site 872 km upriver. Movement rates were substantially faster and the percentage of atypical movements considerably less than reported in more southerly drainages, but may reflect the pristine conditions within the Yukon River, wild origins of the fish, and discrete run timing of the returns. Movement data can provide numerous insights into the status and management of salmon returns, particularly in large river drainages with widely scattered fisheries where management actions in the lower river potentially impact harvests and escapement farther upstream. However, the substantial variation

  11. Reconstructing the Migratory Behavior and Long-Term Survivorship of Juvenile Chinook Salmon under Contrasting Hydrologic Regimes.

    Directory of Open Access Journals (Sweden)

    Anna M Sturrock

    Full Text Available The loss of genetic and life history diversity has been documented across many taxonomic groups, and is considered a leading cause of increased extinction risk. Juvenile salmon leave their natal rivers at different sizes, ages and times of the year, and it is thought that this life history variation contributes to their population sustainability, and is thus central to many recovery efforts. However, in order to preserve and restore diversity in life history traits, it is necessary to first understand how environmental factors affect their expression and success. We used otolith (87Sr/(86Sr in adult Chinook salmon (Oncorhynchus tshawytcha returning to the Stanislaus River in the California Central Valley (USA to reconstruct the sizes at which they outmigrated as juveniles in a wetter (2000 and drier (2003 year. We compared rotary screw trap-derived estimates of outmigrant timing, abundance and size with those reconstructed in the adults from the same cohort. This allowed us to estimate the relative survival and contribution of migratory phenotypes (fry, parr, smolts to the adult spawning population under different flow regimes. Juvenile abundance and outmigration behavior varied with hydroclimatic regime, while downstream survival appeared to be driven by size- and time-selective mortality. Although fry survival is generally assumed to be negligible in this system, >20% of the adult spawners from outmigration year 2000 had outmigrated as fry. In both years, all three phenotypes contributed to the spawning population, however their relative proportions differed, reflecting greater fry contributions in the wetter year (23% vs. 10% and greater smolt contributions in the drier year (13% vs. 44%. These data demonstrate that the expression and success of migratory phenotypes vary with hydrologic regime, emphasizing the importance of maintaining diversity in a changing climate.

  12. Early migration and estuary stopover of introduced chinook salmon population in the Lapataia River Basin, southern Tierra del Fuego Island

    Science.gov (United States)

    Chalde, T.; Fernández, D. A.

    2017-12-01

    Established populations of chinook salmon (Oncorhynchus tshawytscha) have recently been reported in South America, at both Atlantic and Pacific basins. Several studies have evaluated different aspects of their life histories; however, little is known about the use of the estuaries by the juveniles of these populations. We examined spawning time, seaward migration timing, growth rate, scale patterns, diet, and geometric morphometric, contrasting the early life history during freshwater and estuary residence of a chinook population established in Lapataia Basin. Fall run spawning took place in March-April and the parr emerged in September. Two distinct seaward migration patterns were identified from sein net fishing records: one population segment migrating earlier to the estuary in October and a second group migrating later in February. The growth rate of fish captured at the estuary was significantly higher than the fish captured in freshwater. In addition, higher scale intercirculi distances were observed in estuary fish showing differences in growth rate. The feeding habitat in fish captured in both environments changed through time from bottom feeding to surface feeding and from significant diet overlap to no overlap. The morphology of the fish captured at the estuary was associated with the elongation of the caudal peduncle and a decrease in the condition factor index, both changes related to smolt transformation. The earlier migration and the higher growth rate of juveniles in the estuary together with fish of 1 + yo captured in this environment reveal that the estuary of Lapataia Basin is not only a stopover for the chinook salmon, but also a key habitat to reside and feed previous to the final seaward migration.

  13. Migratory Patterns of Wild Chinook Salmon Oncorhynchus tshawytscha Returning to a Large, Free-Flowing River Basin