The role of emergent wetlands as potential rearing habitats for juvenile salmonids

Science.gov (United States)

Henning, Julie A.; Gresswell, Robert E.; Flemming, Ian A.

2006-01-01

A recent trend of enhancing freshwater emergent wetlands for waterfowl and other wildlife has raised concern about the effects of such measures on juvenile salmonids. We undertook this study to quantify the degree and extent of juvenile Pacific salmon Oncorhynchus spp. utilization of enhanced and unenhanced emergent wetlands within the floodplain of the lower Chehalis River, Washington, and to determine the fate of the salmon using them. Enhanced emergent wetlands contained water control structures that provided an outlet for fish emigration and a longer hydroperiod for rearing than unenhanced wetlands. Age-0 and age-1 coho salmon O. kisutch were the most common salmonid at all sites, enhanced wetlands having significantly higher age-1 abundance than unenhanced wetlands that were a similar distance from the main-stem river. Yearling coho salmon benefited from rearing in two enhanced wetland habitats, where their specific growth rate and minimum estimates of survival (1.43%/d by weight and 30%; 1.37%/d and 57%) were comparable to those in other side-channel rearing studies. Dissolved oxygen concentrations decreased in emergent wetlands throughout the season and approached the limits lethal to juvenile salmon by May or June each year. Emigration patterns suggested that age-0 and age-1 coho salmon emigrated as habitat conditions declined. This observation was further supported by the results of an experimental release of coho salmon. Survival of fish utilizing emergent wetlands was dependent on movement to the river before water quality decreased or stranding occurred from wetland desiccation. Thus, our results suggest that enhancing freshwater wetlands via water control structures can benefit juvenile salmonids, at least in the short term, by providing conditions for greater growth, survival, and emigration.

Evaluation of Juvenile Salmonid Outmigration and Survival in the Lower Umatilla River Basin, Annual Report 2003-2006.

Energy Technology Data Exchange (ETDEWEB)

White, Tara

2007-02-01

This report summarizes activities conducted by the Oregon Department of Fish and Wildlife's Juvenile Outmigration and Survival M&E project in the Umatilla River subbasin between 2004-2006. Information is used to make informed decisions on hatchery effectiveness, natural production success, passage improvement and flow enhancement strategies. Data collected includes annual estimates of smolt abundance, migration timing, and survival, life history characteristics and productivity status and trends for spring and fall Chinook salmon, coho salmon and summer steelhead. Productivity data provided is the key subbasin scale measure of the effectiveness of salmon and steelhead restoration actions in the Umatilla River. Information is also used for regional planning and recovery efforts of Mid-Columbia River (MCR) ESA-listed summer steelhead. Monitoring is conducted via smolt trapping and PIT-tag interrogation at Three Mile Falls Dam. The Umatilla Juvenile Outmigration and Survival Project was established in 1994 to evaluate the success of management actions and fisheries restoration efforts in the Umatilla River Basin. Project objectives for the 2004-2006 period were to: (1) operate the PIT tag detection system at Three Mile Falls Dam (TMFD), (2) enhance provisional PIT-tag interrogation equipment at the east bank adult fish ladder, (3) monitor the migration timing, abundance and survival of naturally-produced juvenile salmonids and trends in natural production, (4) determine migration parameters and survival of hatchery-produced fish representing various rearing, acclimation and release strategies, (5) evaluate the relative survival between transported and non-transported fish, (6) monitor juvenile life history characteristics and evaluate trends over time, (7) investigate the effects of river, canal, fishway operations and environmental conditions on smolt migration and survival, (8) document the temporal distribution and diversity of resident fish species, and (9

Survival estimates for the passage of juvenile salmonids through Snake River dams and reservoirs, 1996. Annual report

International Nuclear Information System (INIS)

Smith, S.G.; Muir, W.D.; Hockersmith, E.E.; Achord, S.; Eppard, M.B.; Ruehle, T.E.; Williams, J.G.

1998-02-01

In 1996, the National Marine Fisheries Service and the University of Washington completed the fourth year of a multi-year study to estimate survival of juvenile salmonids (Oncorhynchus spp.) passing through dams and reservoirs on the Snake River. Actively migrating smolts were collected near the head of Lower Granite Reservoir and at Lower Granite Dam, tagged with passive integrated transponder (PIT) tags, and released to continue their downstream migration. Individual smolts were subsequently detected at PIT-tag detection facilities at Lower Granite, Little Goose, Lower Monumental, McNary, John Day and Bonneville Dams. Survival estimates were calculated using the Single-Release (SR) and Paired-Release (PR) Models. Timing of releases of tagged hatchery steelhead (O. mykiss) from the head of Lower Granite Reservoir and yearling chinook salmon (O. tshawytscha) from Lower Granite Dam in 1996 spanned the major portion of their juvenile migrations. Specific research objectives in 1996 were to (1) estimate reach and project survival in the Snake River using the Single-Release and Paired-Release Models throughout the yearling chinook salmon and steelhead migrations, (2) evaluate the performance of the survival-estimation models under prevailing operational and environmental conditions in the Snake River, and (3) synthesize results from the 4 years of the study to investigate relationships between survival probabilities, travel times, and environmental factors such as flow levels and water temperature

Survival Estimates for the Passage of Juvenile Salmonids through Snake River Dams and Reservoirs, 1996 Annual Report

Energy Technology Data Exchange (ETDEWEB)

Smith, Steven G.

1998-02-01

In 1996, the National Marine Fisheries Service and the University of Washington completed the fourth year of a multi-year study to estimate survival of juvenile salmonids (Oncorhynchus spp.) passing through dams and reservoirs on the Snake River. Actively migrating smolts were collected near the head of Lower Granite Reservoir and at Lower Granite Dam, tagged with passive integrated transponder (PIT) tags, and released to continue their downstream migration. Individual smolts were subsequently detected at PIT-tag detection facilities at Lower Granite, Little Goose, Lower Monumental, McNary, John Day and Bonneville Dams. Survival estimates were calculated using the Single-Release (SR) and Paired-Release (PR) Models. Timing of releases of tagged hatchery steelhead (O. mykiss) from the head of Lower Granite Reservoir and yearling chinook salmon (O. tshawytscha) from Lower Granite Dam in 1996 spanned the major portion of their juvenile migrations. Specific research objectives in 1996 were to (1) estimate reach and project survival in the Snake River using the Single-Release and Paired-Release Models throughout the yearling chinook salmon and steelhead migrations, (2) evaluate the performance of the survival-estimation models under prevailing operational and environmental conditions in the Snake River, and (3) synthesize results from the 4 years of the study to investigate relationships between survival probabilities, travel times, and environmental factors such as flow levels and water temperature.

Survival Estimates for the Passage of Juvenile Salmonids through Snake River Dams and Reservoirs, 1997 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Hockersmith, Eric E.

1999-03-01

This report consists of two parts describing research activities completed during 1997 under Bonneville Power Administration Project Number 93-29. Part 1 provides reach survival and travel time estimates for 1997 for PIT-tagged hatchery steelhead and yearling chinook salmon in the Snake and Columbia Rivers. The results are reported primarily in the form of tables and figures with a minimum of text. More detailed information on methodology and the statistical models used in the analysis are provided in previous annual reports cited in the text. Analysis of the relationships among travel time, survival, and environmental factors for 1997 and previous years of the study will be reported elsewhere. Part 2 of this report describes research to determine areas of loss and delay for juvenile hatchery salmonids above Lower Granite Reservoir.

Physiological Assessment of Wild and Hatchery Juvenile Salmonids : Final Report, 2003.

Energy Technology Data Exchange (ETDEWEB)

Larsen, Donald A.; Beckman, Brian R.; Dickhoff, Walton W.

2003-08-01

It is generally held that hatchery-reared salmonids are of inferior quality and have lower smolt-to-adult survival compared to naturally-reared salmon. The overall objectives of the work performed under this contract were the following: (1) Characterize the physiology and development of naturally rearing juvenile salmonids to: (2) Allow for the design of effective rearing programs for producing wild-like smolts in supplementation and production hatchery programs. (3) Examine the relationship between growth rate and size on the physiology and migratory performance of fish reared in hatchery programs. (4) Examine the interaction of rearing temperature and feed rate on the growth and smoltification of salmon for use in producing a more wild-like smolt in hatchery programs.

Juvenile salmonid use of freshwater emergent wetlands in the floodplain and its implications for conservation management

Science.gov (United States)

Henning, Julie A.; Gresswell, Robert E.; Fleming, Ian A.

2006-01-01

A recent trend of enhancing freshwater emergent wetlands for waterfowl and other wildlife has raised concern about the effects of such measures on juvenile salmonids. We undertook this study to quantify the degree and extent of juvenile Pacific salmon Oncorhynchus spp. utilization of enhanced and unenhanced emergent wetlands within the floodplain of the lower Chehalis River, Washington, and to determine the fate of the salmon using them. Enhanced emergent wetlands contained water control structures that provided an outlet for fish emigration and a longer hydroperiod for rearing than unenhanced wetlands. Age-0 and age-1 coho salmon O. kisutch were the most common salmonid at all sites, enhanced wetlands having significantly higher age-1 abundance than unenhanced wetlands that were a similar distance from the main-stem river. Yearling coho salmon benefited from rearing in two enhanced wetland habitats, where their specific growth rate and minimum estimates of survival (1.43%/d by weight and 30%; 1.37%/d and 57%) were comparable to those in other side-channel rearing studies. Dissolved oxygen concentrations decreased in emergent wetlands throughout the season and approached the limits lethal to juvenile salmon by May or June each year. Emigration patterns suggested that age-0 and age-1 coho salmon emigrated as habitat conditions declined. This observation was further supported by the results of an experimental release of coho salmon. Survival of fish utilizing emergent wetlands was dependent on movement to the river before water quality decreased or stranding occurred from wetland desiccation. Thus, our results suggest that enhancing freshwater wetlands via water control structures can benefit juvenile salmonids, at least in the short term, by providing conditions for greater growth, survival, and emigration.

Design and Analysis of Salmonid Tagging Studies in the Columbia Basin : Evaluating Wetland Restoration Projects in the Columbia River Estuary using Hydroacoustic Telemetry Arrays to Estimate Movement, Survival, and Residence Times of Juvenile Salmonids, Volume XXII (22).

Energy Technology Data Exchange (ETDEWEB)

Perry, Russell W.; Skalski, John R.

2008-08-01

Wetlands in the Columbia River estuary are actively being restored by reconnecting these habitats to the estuary, making more wetland habitats available to rearing and migrating juvenile salmon. Concurrently, thousands of acoustically tagged juvenile salmonids are released into the Columbia River to estimate their survival as they migrate through the estuary. Here, we develop a release-recapture model that makes use of these tagged fish to measure the success of wetland restoration projects in terms of their contribution to populations of juvenile salmon. Specifically, our model estimates the fraction of the population that enter the wetland, survival within the wetland, and the mean residence time of fish within the wetland. Furthermore, survival in mainstem Columbia River downstream of the wetland can be compared between fish that remained the mainstem and entered the wetland. These conditional survival estimates provide a means of testing whether the wetland improves the subsequent survival of juvenile salmon by fostering growth or improving their condition. Implementing such a study requires little additional cost because it takes advantage of fish already released to estimate survival through the estuary. Thus, such a study extracts the maximum information at minimum cost from research projects that typically cost millions of dollars annually.

Gas bubble disease monitoring and research of juvenile salmonids

International Nuclear Information System (INIS)

Maule, A.G.; Beeman, J.; Hans, K.M.; Mesa, M.G.; Haner, P.; Warren, J.J.

1997-10-01

This document describes the project activities 1996--1997 contract year. This report is composed of three chapters which contain data and analyses of the three main elements of the project: field research to determine the vertical distribution of migrating juvenile salmonids, monitoring of juvenile migrants at dams on the Snake and Columbia rivers, and laboratory experiments to describe the progression of gas bubble disease signs leading to mortality. The major findings described in this report are: A miniature pressure-sensitive radio transmitter was found to be accurate and precise and, after compensation for water temperature, can be used to determine the depth of tagged-fish to within 0.32 m of the true depth (Chapter 1). Preliminary data from very few fish suggest that depth protects migrating juvenile steelhead from total dissolved gas supersaturation (Chapter 1). As in 1995, few fish had any signs of gas bubble disease, but it appeared that prevalence and severity increased as fish migrated downstream and in response to changing gas supersaturation (Chapter 2). It appeared to gas bubble disease was not a threat to migrating juvenile salmonids when total dissolved gas supersaturation was < 120% (Chapter 2). Laboratory studies suggest that external examinations are appropriate for determining the severity of gas bubble disease in juvenile salmonids (Chapter 3). The authors developed a new method for examining gill arches for intravascular bubbles by clamping the ventral aorta to reduce bleeding when arches were removed (Chapter 3). Despite an outbreak of bacterial kidney disease in the experimental fish, the data indicate that gas bubble disease is a progressive trauma that can be monitored (Chapter 3)

Seasonal Juvenile Salmonid Presence and Migratory Behavior in the Lower Columbia River

Energy Technology Data Exchange (ETDEWEB)

Carter, Jessica A.; McMichael, Geoffrey A.; Welch, Ian D.; Harnish, Ryan A.; Bellgraph, Brian J.

2009-04-30

To facilitate preparing Biological Assessments of proposed channel maintenance projects, the Portland District of the U.S. Army Corps of Engineers contracted the Pacific Northwest National Laboratory to consolidate and synthesize available information about the use of the lower Columbia River and estuary by juvenile anadromous salmonids. The information to be synthesized included existing published documents as well as data from five years (2004-2008) of acoustic telemetry studies conducted in the Columbia River estuary using the Juvenile Salmon Acoustic Telemetry System. For this synthesis, the Columbia River estuary includes the section of the Columbia River from Bonneville Dam at river kilometer (Rkm) 235 downstream to the mouth where it enters the Pacific Ocean. In this report, we summarize the seasonal salmonid presence and migration patterns in the Columbia River estuary based on information from published studies as well as relevant data from acoustic telemetry studies conducted by NOAA Fisheries and the Pacific Northwest National Laboratory (PNNL) between 2004 and 2008. Recent acoustic telemetry studies, conducted using the Juvenile Salmon Acoustic Telemetry System (JSATS; developed by the Portland District of the U.S. Army Corps of Engineers), provided information on the migratory behavior of juvenile steelhead (O. mykiss) and Chinook salmon in the Columbia River from Bonneville Dam to the Pacific Ocean. In this report, Section 2 provides a summary of information from published literature on the seasonal presence and migratory behavior of juvenile salmonids in the Columbia River estuary and plume. Section 3 presents a detailed synthesis of juvenile Chinook salmon and steelhead migratory behavior based on use of the JSATS between 2004 and 2008. Section 4 provides a discussion of the information summarized in the report as well as information drawn from literature reviews on potential effects of channel maintenance activities to juvenile salmonids rearing in

Migrational Characteristics, Biological Observations, and Relative Survival of Juvenile Salmonids Entering the Columbia River Estuary, 1966-1983, 1985 Final Report of Research.

Energy Technology Data Exchange (ETDEWEB)

Dawley, Earl M.

1986-04-01

Natural runs of salmonids in the Columbia River basin have decreased as a result of hydroelectric-dam development, poor land- and forest-management, and over-fishing. This has necessitated increased salmon culture to assure adequate numbers of returning adults. Hatchery procedures and facilities are continually being modified to improve both the efficiency of production and the quality of juveniles produced. Initial efforts to evaluate changes in hatchery procedures were dependent upon adult contributions to the fishery and returns to the hatchery. Procedures were developed for sampling juvenile salmon and steelhead entering the Columbia River estuary and ocean plume. The sampling of hatchery fish at the terminus of their freshwater migration assisted in evaluating hatchery production techniques and identifying migrational or behavioral characteristics that influence survival to and through the estuary. The sampling program attempted to estimate survival of different stocks and define various aspects of migratory behavior in a large river, with flows during the spring freshet from 4 to 17 thousand cubic meters per second (m/sup 3//second).

The design and analysis of salmonid tagging studies in the Columbia River. Volume 7: Monte-Carlo comparison of confidence internal procedures for estimating survival in a release-recapture study, with applications to Snake River salmonids

International Nuclear Information System (INIS)

Lowther, A.B.; Skalski, J.

1996-06-01

Confidence intervals for survival probabilities between hydroelectric facilities of migrating juvenile salmonids can be computed from the output of the SURPH software developed at the Center for Quantitative Science at the University of Washington. These intervals have been constructed using the estimate of the survival probability, its associated standard error, and assuming the estimate is normally distributed. In order to test the validity and performance of this procedure, two additional confidence interval procedures for estimating survival probabilities were tested and compared using simulated mark-recapture data. Intervals were constructed using normal probability theory, using a percentile-based empirical bootstrap algorithm, and using the profile likelihood concept. Performance of each method was assessed for a variety of initial conditions (release sizes, survival probabilities, detection probabilities). These initial conditions were chosen to encompass the range of parameter values seen in the 1993 and 1994 Snake River juvenile salmonid survival studies. The comparisons among the three estimation methods included average interval width, interval symmetry, and interval coverage

Comparative Performance of Acoustic-tagged and PIT-tagged Juvenile Salmonids

Energy Technology Data Exchange (ETDEWEB)

Hockersmith, Eric E.; Brown, Richard S.; Liedtke, Theresa L.

2008-02-01

Numerous research tools and technologies are currently being used to evaluate fish passage and survival to determine the impacts of the Federal Columbia River Power System (FCRPS) on endangered and threatened juvenile salmonids, including PIT tags, balloon tags, hydroacoustic evaluations, radio telemetry, and acoustic telemetry. Each has advantages and disadvantages, but options are restricted in some situations because of limited capabilities of a specific technology, lack of detection capability downstream, or availability of adequate numbers of fish. However, there remains concern about the comparative effects of the tag or the tagging procedure on fish performance. The recently developed Juvenile Salmonid Acoustic Telemetry System (JSATS) acoustic transmitter is the smallest active acoustic tag currently available. The goal of this study was to determine whether fish tagged with the JSATS acoustic-telemetry tag can provide unbiased estimates of passage behavior and survival within the performance life of the tag. We conducted both field and laboratory studies to assess tag effects. For the field evaluation we released a total of 996 acoustic-tagged fish in conjunction with 21,026 PIT-tagged fish into the tailrace of Lower Granite Dam on 6 and 13 May. Travel times between release and downstream dams were not significantly different for the majority of the reaches between acoustic-tagged and PIT-tagged fish. In addition to the field evaluation, a series of laboratory experiments were conducted to determine if growth and survival of juvenile Chinook salmon surgically implanted with acoustic transmitters is different than untagged or PIT tagged juvenile Chinook salmon. Only yearling fish with integrated and non-integrated transmitters experienced mortalities, and these were low (<4.5%). Mortality among sub-yearling control and PIT-tag treatments ranged up to 7.7% while integrated and non-integrated treatments had slightly higher rates (up to 8.3% and 7

Acoustic Telemetry Evaluation of Juvenile Salmonid Passage and Survival at John Day Dam, 2011

Energy Technology Data Exchange (ETDEWEB)

Weiland, Mark A.; Woodley, Christa M.; Ploskey, Gene R.; Hughes, James S.; Hennen, Matthew J.; Kim, Jin A.; Deng, Zhiqun; Fu, Tao; Skalski, J. R.; Townsend, Richard L.; Wagner, Katie A.; Fischer, Eric S.; Duncan, Joanne P.; Batten, G.; Carlson, Thomas J.; Carpenter, Scott M.; Cushing, Aaron W.; Elder, T.; Etherington, D. J.; Johnson, Gary E.; Khan, Fenton; Miracle, Ann L.; Mitchell, T. D.; Prather, K.; Rayamajhi, Bishes; Royer, Ida; Seaburg, Adam; Zimmerman, Shon A.

2013-06-21

This report presents survival, behavioral, and fish passage results for tagged yearling Chinook salmon and juvenile steelhead as part of a survival study conducted at John Day Dam during spring 2011. This study was designed to evaluate the passage and survival of yearling Chinook salmon and juvenile steelhead to assist managers in identifying dam operations for compliance testing as stipulated by the 2008 Federal Columbia River Power System Biological Opinion and the 2008 Columbia Basin Fish Accords. Survival estimates were based on a paired-release survival model.

Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing through Bonneville Dam, 2011

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Batten, G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cushing, Aaron W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Jin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Gary E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skalski, J. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Townsend, Richard L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Seaburg, Adam [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodley, Christa M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hughes, James S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carlson, Thomas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carpenter, Scott M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Deng, Zhiqun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Etherington, D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fischer, Eric S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fu, Tao [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Greiner, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hennen, Matthew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Martinez, Jayson J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mitchell, T. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rayamajhi, Bishes [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zimmerman, Shon A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2013-02-15

Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2011. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a virtual/paired-release model. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon using a virtual release, paired reference release survival model. This study supports the U.S. Army Corps of Engineers’ continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Acoustic Telemetry Evaluation of Juvenile Salmonid Passage and Survival at John Day Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Weiland, Mark A.; Woodley, Christa M.; Ploskey, Gene R.; Hughes, James S.; Kim, Jin A.; Deng, Zhiqun; Fu, Tao; Fischer, Eric S.; Skalski, J. R.; Townsend, Richard L.; Duncan, Joanne P.; Hennen, Matthew J.; Wagner, Katie A.; Arntzen, Evan V.; Miller, Benjamin L.; Miracle, Ann L.; Zimmerman, Shon A.; Royer, Ida M.; Khan, Fenton; Cushing, Aaron W.; Etherington, D. J.; Mitchell, T. D.; Elder, T.; Batton, George; Johnson, Gary E.; Carlson, Thomas J.

2013-05-01

This report presents survival, behavioral, and fish passage results for yearling and subyearling Chinook salmon smolts and juvenile steelhead tagged with JSATS acoustic micro-transmitters as part of a survival study conducted at John Day Dam during 2010. This study was designed to evaluate the passage and survival of yearling and subyearling Chinook salmon and juvenile steelhead to assist managers in identifying dam operations for compliance testing as stipulated by the 2008 Federal Columbia River Power System Biological Opinion and the 2008 Columbia Basin Fish Accords. Survival estimates were based on a single-release survival estimate model.

Gas bubble trauma monitoring and research of juvenile salmonids. 1995 Annual report

International Nuclear Information System (INIS)

Maule, A.G.; Mesa, M.G.; Hans, K.M.

1997-07-01

This report describes laboratory and field monitoring studies of gas bubble trauma (GBT) in migrating juvenile salmonids in the Snake and Columbia rivers. The first chapter describes laboratory studies of the progression of GBT signs leading to mortality and the use of the signs for GBT assessment. The progression and severity of GBT signs in juvenile salmonids exposed to different levels of total dissolved gas (TDG) and temperatures was assessed and quantified. Next, the prevalence, severity, and individual variation of GBT signs was evaluated to attempt to relate them to mortality. Finally, methods for gill examination in fish exposed to high TDG were developed and evaluated. Primary findings were: (1) no single sign of GBT was clearly correlated with mortality, but many GBT signs progressively worsened; (2) both prevalence and severity of GBT signs in several tissues is necessary; (3) bubbles in the lateral line were the earliest sign of GBT, showed progressive worsening, and had low individual variation but may develop poorly during chronic exposures; (4) fin bubbles had high prevalence, progressively worsened, and may be a persistent sign of GBT; and (5) gill bubbles appear to be the proximate cause of death but may only be relevant at high TDG levels and are difficult to examine. Chapter Two describes monitoring results of juvenile salmonids for signs of GBT. Emigrating fish were collected and examined for bubbles in fins and lateral lines. Preliminary findings were: (1) few fish had signs of GBT, but prevalence and severity appeared to increase as fish migrated downstream; (2) there was no apparent correlation between GBT signs in the fins, lateral line, or gills; (3) prevalence and severity of GBT was suggestive of long-term, non-lethal exposure to relatively low level gas supersaturated water; and (4) it appeared that GBT was not a threat to migrating juvenile salmonids. 24 refs., 26 figs., 3 tabs

Estimated loss of juvenile salmonids to predation by northern squawfish, walleyes, and smallmouth bass in John Day Reservoir, Columbia River

International Nuclear Information System (INIS)

Rieman, B.E.; Beamesderfer, R.C.; Vigg, S.; Poe, T.P.

1991-01-01

The authors estimated the loss of juvenile salmonids Oncorhynchus spp. to predation by northern squawfish Ptychocheilus oregonensis, walleyes Stizostedion vitreum, and smallmouth bass Micropterus dolomieu in John Day Reservoir during 1983-1986. Their estimates were based on measures of daily prey consumption, predator numbers, and numbers of juvenile salmonids entering the reservoir during the April-August period of migration. They estimated the mean annual loss was 2.7 million juvenile salmonids. Northern squawfish were responsible for 78% of the total loss; walleyes accounted for 13% and smallmouth bass for 9%. Twenty-one percent of the loss occurred in a small area immediately below McNary Dam at the head of John Day Reservoir. The authors estimated that the three predator species consumed 14% of all juvenile salmonids that entered the reservoir. Mortality changed by month and increased late in the migration season. Monthly mortality estimates ranged from 7% in June and 61% in August. Mortality from predation was highest for chinook salmon O. tshawytscha, which migrated in July and August. Despite uncertainties in the estimates, it is clear that predation by resident fish predators can easily account for previously explained mortality of out-migrating juvenile salmonids. Alteration of the Columbia River by dams and a decline in the number of salmonids could have increased the fraction of mortality caused by predation over what is was in the past

Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing through Bonneville Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Kim, Jin A.; Royer, Ida M.; Batten, George W.; Cushing, Aaron W.; Carpenter, Scott M.; Etherington, D. J.; Faber, Derrek M.; Fischer, Eric S.; Fu, Tao; Hennen, Matthew J.; Mitchell, Tyler; Monter, Tyrell J.; Skalski, John R.; Townsend, Richard L.; Zimmerman, Shon A.

2011-12-01

Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2010. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a single-release model. This also was the last year of evaluation of effects of a behavioral guidance device installed in the Powerhouse 2 forebay. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Survival and Passage of Juvenile Chinook Salmon and Steelhead Passing Through Bonneville Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Woodley, Christa M.; Deng, Zhiqun; Carlson, Thomas J.; Kim, Jin A.; Royer, Ida M.; Batten, George W.; Cushing, Aaron W.; Carpenter, Scott M.; Etherington, D. J.; Faber, Derrek M.; Fischer, Eric S.; Fu, Tao; Hennen, Matthew J.; Mitchell, T. D.; Monter, Tyrell J.; Skalski, J. R.; Townsend, Richard L.; Zimmerman, Shon A.

2012-09-01

Pacific Northwest National Laboratory (PNNL) and subcontractors conducted an acoustic-telemetry study of juvenile salmonid fish passage and survival at Bonneville Dam in 2010. The study was conducted to assess the readiness of the monitoring system for official compliance studies under the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a single-release model. This also was the last year of evaluation of effects of a behavioral guidance device installed in the Powerhouse 2 forebay. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Three-dimensional migration behavior of juvenile salmonids in reservoirs and near dams

OpenAIRE

Li, Xinya; Deng, Zhiqun D.; Fu, Tao; Brown, Richard S.; Martinez, Jayson J.; McMichael, Geoffrey A.; Trumbo, Bradly A.; Ahmann, Martin L.; Renholds, Jon F.; Skalski, John R.; Townsend, Richard L.

2018-01-01

To acquire 3-D tracking data on juvenile salmonids, Juvenile Salmon Acoustic Telemetry System (JSATS) cabled hydrophone arrays were deployed in the forebays of two dams on the Snake River and at a mid-reach reservoir between the dams. The depth distributions of fish were estimated by statistical analyses performed on large 3-D tracking data sets from ~33,500 individual acoustic tagged yearling and subyearling Chinook salmon and juvenile steelhead at the two dams in 2012 and subyearling Chinoo...

Hydroacoustic Evaluation of Juvenile Salmonid Passage at The Dalles Dam Sluiceway, 2005

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Khan, Fenton; Hedgepeth, J; Mueller, Robert P.; Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.; Skalski, John R.

2006-06-01

The U.S. Army Corps of Engineers Portland District engaged the Pacific Northwest National Laboratory to evaluate fish passage at The Dalles Dam powerhouse in 2005. The goal of the study was to provide information on smolt passage that will inform decisions on long-term measures and operations to enhance sluiceway passage and reduce turbine passage to improve smolt survival at the dam. The study addressed one of the main programs dedicated to improving juvenile salmonid survival at The Dalles Dam: Surface Flow Bypass. The study objectives (see below) were met using a combination of hydroacoustic and hydraulic data. The study incorporated fixed-location hydroacoustic methods across the entire powerhouse, with especially intense sampling using multiple split-beam transducers at all sluiceway portals. We did not sample fish passage at the spillway in 2005. In the sluiceway nearfield, we used an acoustic camera to track fish movements. The fish data were interpreted with hydraulic data from a computational fluid dynamics (CFD) model. Fish passage data were collected in the framework of an “experiment” using a randomized block design (3-day treatments; two treatments) to compare two sluiceway operational configurations: Sluice 2+5 and Sluice 2+19 (six gates open for each configuration). Total project outflow was 76% of the 10-year average for spring and 71% of the 10-year average for summer. Based on these findings, we make the following recommendations: 1) The sluice should be operated 24 h/d from April until November. 2) Open six rather than three sluice gates to take advantage of the maximum hydraulic capacity of the sluiceway. 3) Open the three gates above the western-most operating main turbine unit and the three gates at MU 8 where turbine passage rates are relatively high. 4) Operate the turbine units below open sluice gates as a standard fish operations procedure. 5) Develop hydraulic and entrance enhancements to the sluiceway to tap the potential of The

Introduced northern pike consumption of salmonids in Southcentral Alaska

Science.gov (United States)

Sepulveda, Adam J.; Rutz, David S.; Dupuis, Aaron W; Shields, Patrick A; Dunker, Kristine J.

2015-01-01

The impacts of introduced northern pike (Esox lucius) on salmonid populations have attracted much attention because salmonids are popular subsistence, sport and commercial fish. Concern over the predatory effects of introduced pike on salmonids is especially high in Southcentral Alaska, where pike were illegally introduced to the Susitna River basin in the 1950s. We used pike abundance, growth, and diet estimates and bioenergetics models to characterise the realised and potential consumptive impacts that introduced pike (age 2 and older) have on salmonids in Alexander Creek, a tributary to the Susitna River. We found that juvenile salmonids were the dominant prey item in pike diets and that pike could consume up to 1.10 metric tons (realised consumption) and 1.66 metric tons (potential consumption) of juvenile salmonids in a summer. Age 3–4 pike had the highest per capita consumption of juvenile salmonids, and age 2 and age 3–4 pike had the highest overall consumption of juvenile salmonid biomass. Using historical data on Chinook salmon and pike potential consumption of juvenile salmonids, we found that pike consumption of juvenile salmonids may lead to collapsed salmon stocks in Alexander Creek. Taken together, our results indicate that pike consume a substantial biomass of juvenile salmonids in Alexander Creek and that coexistence of pike and salmon is unlikely without management actions to reduce or eliminate introduced pike.

Analyses of potential factors affecting survival of juvenile salmonids volitionally passing through turbines at McNary and John Day Dams, Columbia River

Science.gov (United States)

Beeman, John; Hansel, Hal; Perry, Russell; Hockersmith, Eric; Sandford, Ben

2011-01-01

This report describes analyses of data from radio- or acoustic-tagged juvenile salmonids passing through hydro-dam turbines to determine factors affecting fish survival. The data were collected during a series of studies designed to estimate passage and survival probabilities at McNary (2002-09) and John Day (2002-03) Dams on the Columbia River during controlled experiments of structures or operations at spillways. Relatively few tagged fish passed turbines in any single study, but sample sizes generally were adequate for our analyses when data were combined from studies using common methods over a series of years. We used information-theoretic methods to evaluate biological, operational, and group covariates by creating models fitting linear (all covariates) or curvilinear (operational covariates only) functions to the data. Biological covariates included tag burden, weight, and water temperature; operational covariates included spill percentage, total discharge, hydraulic head, and turbine unit discharge; and group covariates included year, treatment, and photoperiod. Several interactions between the variables also were considered. Support of covariates by the data was assessed by comparing the Akaike Information Criterion of competing models. The analyses were conducted because there was a lack of information about factors affecting survival of fish passing turbines volitionally and the data were available from past studies. The depth of acclimation, tag size relative to fish size (tag burden), turbine unit discharge, and area of entry into the turbine intake have been shown to affect turbine passage survival of juvenile salmonids in other studies. This study indicates that turbine passage survival of the study fish was primarily affected by biological covariates rather than operational covariates. A negative effect of tag burden was strongly supported in data from yearling Chinook salmon at John Day and McNary dams, but not for subyearling Chinook salmon or

Effect of commercially available egg cures on the survival of juvenile salmonids.

Directory of Open Access Journals (Sweden)

Shaun Clements

Full Text Available There is some concern that incidental consumption of eggs cured with commercially available cures for the purpose of sport fishing causes mortality in juvenile salmon. We evaluated this by feeding juvenile spring Chinook (Oncorhynchus tshawytscha and steelhead (O. mykiss with eggs cured with one of five commercially available cures. We observed significant levels of mortality in both pre-smolts and smolts. Depending on the experiment, 2, 3, or 4 of the cures were associated with mortality. Mortality tended to be higher in the smolts than in the parr, but there was no clear species effect. The majority of mortality occurred within the first 10 d of feeding. Removal of sodium sulfite from the cure significantly reduced the level of mortality. Soaking the eggs prior to feeding did not reduce mortality. We observed a clear relationship between the amount of cured egg consumed each day and the survival time. We conclude that consumption of eggs cured with sodium sulfite has the potential to cause mortality in juvenile steelhead and Chinook salmon in the wild.

Effect of commercially available egg cures on the survival of juvenile salmonids

Science.gov (United States)

Clements, S.; Chitwood, R.; Schreck, C.B.

2011-01-01

There is some concern that incidental consumption of eggs cured with commercially available cures for the purpose of sport fishing causes mortality in juvenile salmon. We evaluated this by feeding juvenile spring Chinook (Oncorhynchus tshawytscha) and steelhead (O. mykiss) with eggs cured with one of five commercially available cures. We observed significant levels of mortality in both pre-smolts and smolts. Depending on the experiment, 2, 3, or 4 of the cures were associated with mortality. Mortality tended to be higher in the smolts than in the parr, but there was no clear species effect. The majority of mortality occurred within the first 10 d of feeding. Removal of sodium sulfite from the cure significantly reduced the level of mortality. Soaking the eggs prior to feeding did not reduce mortality. We observed a clear relationship between the amount of cured egg consumed each day and the survival time. We conclude that consumption of eggs cured with sodium sulfite has the potential to cause mortality in juvenile steelhead and Chinook salmon in the wild.

Survival Rates of Juvenile Salmonids Passing Through the Bonneville Dam and Spillway in 2008

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R.; Weiland, Mark A.; Faber, Derrek M.; Deng, Zhiqun; Johnson, Gary E.; Hughes, James S.; Zimmerman, Shon A.; Monter, Tyrell J.; Cushing, Aaron W.; Wilberding, Matthew C.; Durham, Robin E.; Townsend, R. L.; Skalski, J. R.; Buchanan, Rebecca A.; Kim, Jina; Fischer, Eric S.; Meyer, Matthew M.; McComas, Roy L.; Everett, Jason

2009-12-28

This report describes a 2008 acoustic telemetry survival study conducted by the Pacific Northwest National Laboratory for the Portland District of the U.S. Army Corps of Engineers. The study estimated the survival of juvenile Chinook salmon and steelhead passing Bonneville Dam (BON) and its spillway. Of particular interest was the relative survival of smolts detected passing through end spill bays 1-3 and 16-18, which had deep flow deflectors immediately downstream of spill gates, versus survival of smolts passing middle spill bays 4-15, which had shallow flow deflectors.

Survival Estimates for the Passage of Spring-Migrating Juvenile Salmonids through Snake and Columbia River Dams and Reservoirs, 2001-2002 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Zabel, Richard; Williams, John G.; Smith, Steven G. (Northwest and Alaska Fisheries Science Center, Fish Ecology Division, Seattle, WA)

2002-06-01

In 2001, the National Marine Fisheries Service and the University of Washington completed the ninth year of a study to estimate survival and travel time of juvenile salmonids (Oncorhynchus spp.) passing through dams and reservoirs on the Snake and Columbia Rivers. All estimates were derived from passive integrated transponder (PIT)-tagged fish. We PIT tagged and released at Lower Granite Dam a total of 17,028 hatchery and 3,550 wild steelhead. In addition, we utilized fish PIT tagged by other agencies at traps and hatcheries upstream of the hydropower system and sites within the hydropower system. PIT-tagged smolts were detected at interrogation facilities at Lower Granite, Little Goose, Lower Monumental, McNary, John Day, and Bonneville Dams and in the PIT-tag detector trawl operated in the Columbia River estuary. Survival estimates were calculated using the Single-Release Model. Primary research objectives in 2001 were to: (1) estimate reach and project survival and travel time in the Snake and Columbia Rivers throughout the yearling chinook salmon and steelhead migrations; (2) evaluate relationships between survival estimates and migration conditions; and (3) evaluate the survival-estimation models under prevailing conditions. This report provides reach survival and travel time estimates for 2001 for PIT-tagged yearling chinook salmon and steelhead (hatchery and wild) in the Snake and Columbia Rivers. Results are reported primarily in the form of tables and figures with a minimum of text. More details on methodology and statistical models used are provided in previous reports cited in the text. Results for summer-migrating chinook salmon will be reported separately.

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

Turbulence Investigation and Reproduction for Assisting Downstream Migrating Juvenile Salmonids, Part I of II, 2001-2002 Final Report.

Energy Technology Data Exchange (ETDEWEB)

Hotchkiss, Rollin H. (Washington State University, Department of Civil and Environmental Engineers, Albrook Hydraulics Laboratory)

2002-12-01

Turbulence in gravel bed rivers plays a critical role in most stream processes including contaminant and nutrient transport, aquatic habitat selection, and natural channel design. While most hydraulic designs and fluid models are based on bulk velocity, migrating juvenile salmon experience and react to the temporally varied turbulent fluctuations. Without properly understanding and accounting for the continuous turbulent motions proper fishway design and guidance are impossible. Matching temporally varied flow to fish reactions is the key to guiding juvenile salmonids to safe passageways. While the ideal solution to fish guidance design would be to use specific fluid action-fish reaction mechanisms, such concrete cause and effect relations have not been established. One way to approach the problem of guidance is to hypothesize that in an environment lacking obvious bulk flow cues (like the reservoir environment), turbulent flow conditions similar to those experienced by juvenile salmonids in natural migration corridors will be attractive to juvenile salmonids. Proof of this hypothesis requires three steps: (1) gathering data on turbulence characteristics in natural migration corridors, (2) reproduction of the turbulence parameters in a controlled environment, and (3) testing the reproduced turbulence on actively migrating juvenile salmonids for increased passage efficiencies. The results from the third step have not been finalized, therefore this report will focus on understanding turbulent processes in gravel bed rivers and reproduction of turbulence in controlled environments for use in fish passage technologies. The purposes of this report are to (1) present data collected in natural gravel bed rivers, (2) present a simple method for reproduction of appropriate turbulence levels in a controlled environment, (3) compare these results to those from one prototype surface collector (PSC), and (4) discuss the implications on fish passage design.

Evaluation of Behavioral Guidance Structure on Juvenile Salmonid Passage and Survival at Bonneville Dam in 2009

Energy Technology Data Exchange (ETDEWEB)

Faber, Derrek M.; Ploskey, Gene R.; Weiland, Mark A.; Deng, Zhiqun; Hughes, James S.; Kim, Jin A.; Fu, Tao; Fischer, Eric S.; Monter, Tyrell J.; Skalski, J. R.

2011-03-01

Pacific Northwest National Laboratory (PNNL) conducted an acoustic-telemetry study at Bonneville Dam in 2009 to evaluate the effects of a behavioral guidance structure (BGS) in the Bonneville Dam second powerhouse forebay on fish passage and survival through the second powerhouse (B2), the dam as a whole, and through the first powerhouse and spillway combined. The BGS was deployed to increase the survival of fish passing through B2 by increasing the percentage of outmigrating smolts entering the B2 Corner Collector (B2CC)—a surface flow outlet known to be a relatively benign route for downstream passage at this dam. The study relied on releases of live Juvenile Salmon Acoustic Telemetry System tagged smolts in the Columbia River and used acoustic telemetry to evaluate the approach, passage, and survival of passing juvenile salmon. Study results indicated that having turbine 11 in service is important for providing flow conditions that are comparable to those observed in pre-BGS years (2004 and 2005) and in 2008. This study supports the U.S. Army Corps of Engineers continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Introduced northern pike predation on salmonids in southcentral Alaska

Science.gov (United States)

Sepulveda, Adam J.; Rutz, David S.; Ivey, Sam S.; Dunker, Kristine J.; Gross, Jackson A.

2013-01-01

Northern pike (Esox lucius) are opportunistic predators that can switch to alternative prey species after preferred prey have declined. This trophic adaptability allows invasive pike to have negative effects on aquatic food webs. In Southcentral Alaska, invasive pike are a substantial concern because they have spread to important spawning and rearing habitat for salmonids and are hypothesised to be responsible for recent salmonid declines. We described the relative importance of salmonids and other prey species to pike diets in the Deshka River and Alexander Creek in Southcentral Alaska. Salmonids were once abundant in both rivers, but they are now rare in Alexander Creek. In the Deshka River, we found that juvenile Chinook salmon (Oncorhynchus tshawytscha) and coho salmon (O. kisutch) dominated pike diets and that small pike consumed more of these salmonids than large pike. In Alexander Creek, pike diets reflected the distribution of spawning salmonids, which decrease with distance upstream. Although salmonids dominated pike diets in the lowest reach of the stream, Arctic lamprey (Lampetra camtschatica) and slimy sculpin (Cottus cognatus) dominated pike diets in the middle and upper reaches. In both rivers, pike density did not influence diet and pike consumed smaller prey items than predicted by their gape-width. Our data suggest that (1) juvenile salmonids are a dominant prey item for pike, (2) small pike are the primary consumers of juvenile salmonids and (3) pike consume other native fish species when juvenile salmonids are less abundant. Implications of this trophic adaptability are that invasive pike can continue to increase while driving multiple species to low abundance.

Significance of Selective Predation and Development of Prey Protection Measures for Juvenile Salmonids in the Columbia and Snake River Reservoirs: Annual Progress Report, February 1991-February 1992.

Energy Technology Data Exchange (ETDEWEB)

Poe, Thomas P.

1992-12-31

This document is the 1991 annual report of progress for the Bonneville Power Administration (BPA) research Project conducted by the US Fish and Wildlife Service (FWS). Our approach was to present the progress achieved during 1991 in a series of separate reports for each major project task. Each report is prepared in the format of a scientific paper and is able to stand alone, whatever the state of progress or completion. This project has two major goals. One is to understand the significance of selective predation and prey vulnerability by determining if substandard juvenile salmonids (dead, injured, stressed, diseased, or naive) are more vulnerable to predation by northern squawfish, than standard or normal juvenile salmonids. The second goal is to develop and test prey protection measures to control predation on juvenile salmonids by reducing predator-smolt encounters or predator capture efficiency.

Passage survival of juvenile steelhead, coho salmon, and Chinook salmon in Lake Scanewa and at Cowlitz Falls Dam, Cowlitz River, Washington, 2010–16

Science.gov (United States)

Liedtke, Theresa L.; Kock, Tobias J.; Hurst, William

2018-04-03

A multi-year evaluation was conducted during 2010–16 to evaluate passage survival of juvenile steelhead (Oncorhynchus mykiss), Chinook salmon (O. tshawytscha), and coho salmon (O. kisutch) in Lake Scanewa, and at Cowlitz Falls Dam in the upper Cowlitz River Basin, Washington. Reservoir passage survival was evaluated in 2010, 2011, and 2016, and included the tagging and release of 1,127 juvenile salmonids. Tagged fish were released directly into the Cowlitz and Cispus Rivers, 22.3 and 8.9 km, respectively, upstream of the reservoir, and were monitored as they moved downstream into, and through the reservoir. A single release-recapture survival model was used to analyze detection records and estimate reservoir passage survival, which was defined as successful passage from reservoir entry to arrival at Cowlitz Falls Dam. Tagged fish generally moved quickly downstream of the release sites and, on average, arrived in the dam forebay within 2 d of release. Median travel time from release to first detection at the dam ranged from 0.23 to 0.96 d for juvenile steelhead, from 0.15 to 1.11 d for juvenile coho salmon, and from 0.18 to 1.89 d for juvenile Chinook salmon. Minimum reservoir passage survival probabilities were 0.960 for steelhead, 0.855 for coho salmon and 0.900 for Chinook salmon.Dam passage survival was evaluated at the pilot-study level during 2013–16 and included the tagging and release of 2,512 juvenile salmonids. Juvenile Chinook salmon were evaluated during 2013–14, and juvenile steelhead and coho salmon were evaluated during 2015–16. A paired-release study design was used that included release sites located upstream and downstream of Cowlitz Falls Dam. The downstream release site was positioned at the downstream margin of the dam’s tailrace, which allowed dam passage survival to be measured in a manner that included mortality that occurred in the passage route and in the dam tailrace. More than one-half of the tagged Chinook salmon (52 percent

Turbulence investigation and reproduction for assisting downstream migrating juvenile salmonids, Part II of II: Effects of induced turbulence on behavior of juvenile salmon, 2001-2005 final report

Science.gov (United States)

Perry, R.; Farley , M.; Hansen, G.; Morse , J.; Rondorf, D.

2005-01-01

Passage through dams is a major source of mortality of anadromous juvenile salmonids because some populations must negotiate up to eight dams in Columbia and Snake rivers. Dams cause direct mortality when fish pass through turbines, but dams may also cause indirect mortality by altering migration conditions in rivers. Forebays immediately upstream of dams have decreased the water velocity of rivers and may contribute substantially to the total migration delay of juvenile salmonids. Recently, Coutant (2001a) suggested that in addition to low water velocities, lack of natural turbulence may contribute to migration delay by causing fish to lose directional cues. Coutant (2001a) further hypothesized that restoring turbulence in dam forebays may reduce migration delay by providing directional cues that allow fish to find passage routes more quickly (Coutant 2001a). Although field experiments have yielded proof of the concept of using induced turbulence to guide fish to safe passage routes, little is known about mechanisms actually causing behavioral changes. To test hypotheses about how turbulence influences movement and behavior of migrating juvenile salmonids, we conducted two types of controlled experiments at Cowlitz Falls Dam, Washington. A common measure of migration delay is the elapsed time between arrival at, and passage through, a dam. Therefore, for the first set of experiments, we tested the effect of induced turbulence on the elapsed time needed for fish to traverse through a raceway and pass over a weir at its downstream end (time trial experiment). If turbulence helps guide fish to passage routes, then fish should pass through the raceway quicker in the presence of appropriately scaled and directed turbulent cues. Second, little is known about how the physical properties of water movement provide directional cues to migrating juvenile salmonids. To examine the feasibility of guiding fish with turbulence, we tested whether directed turbulence could guide

Relationship of external fish condition to pathogen prevalence and out-migration survival in juvenile steelhead

Science.gov (United States)

Hostetter, N.J.; Evans, A.F.; Roby, D.D.; Collis, K.; Hawbecker, M.; Sandford, B.P.; Thompson, D.E.; Loge, F.J.

2011-01-01

Understanding how the external condition of juvenile salmonids is associated with internal measures of health and subsequent out-migration survival can be valuable for population monitoring programs. This study investigated the use of a rapid, nonlethal, external examination to assess the condition of run-of-the-river juvenile steelhead Oncorhynchus mykiss migrating from the Snake River to the Pacific Ocean. We compared the external condition (e.g., body injuries, descaling, external signs of disease, fin damage, and ectoparasite infestations) with (1) the internal condition of a steelhead as measured by the presence of selected pathogens detected by histopathology and polymerase chain reaction analysis and (2) out-migration survival through the Snake and Columbia rivers as determined by passive integrated transponder (PIT) tag technology. The results from steelhead captured and euthanized (n = 222) at Lower Monumental Dam on the lower Snake River in 2008 indicated that external condition was significantly correlated with selected measures of internal condition. The odds of testing positive for a pathogen were 39.2, 24.3, and 5.6 times greater for steelhead with severe or moderate external signs of disease or more than 20% descaling, respectively. Capture-recapture models of 22,451 PIT-tagged steelhead released at Lower Monumental Dam in 2007-2009 indicated that external condition was significantly correlated with juvenile survival. The odds of outmigration survival for steelhead with moderate or severe external signs of disease, more than 20% descaling, or severe fin damage were 5.7, 4.9, 1.6, and 1.3 times lower, respectively, than those for steelhead without these external conditions. This study effectively demonstrated that specific measures of external condition were associated with both the internal condition and out-migration survival of juvenile steelhead. ?? American Fisheries Society 2011.

Acoustic Imaging Evaluation of Juvenile Salmonid Behavior in the Immediate Forebay of the Water Temperature Control Tower at Cougar Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Johnson, Gary E.; Royer, Ida M.; Phillips, Nathan RJ; Hughes, James S.; Fischer, Eric S.; Ploskey, Gene R.

2011-10-01

This report presents the results of an evaluation of juvenile Chinook salmonid (Oncorhynchus tshawytscha) behavior in the immediate forebay of the Water Temperature Control (WTC) tower at Cougar Dam in 2010. The study was conducted by the Pacific Northwest National Laboratory for the U.S. Army Corps of Engineers. The overall goal of the study was to characterize juvenile salmonid behavior and movement patterns in the immediate forebay of the WTC tower for fisheries resource managers to use to make decisions on bioengineering designs for long-term structures and/or operations to facilitate safe downstream passage for juvenile salmonids. We collected acoustic imaging (Dual-Frequency Identification Sonar; DIDSON) data from February 1, 2010 through January 31, 2011 to evaluate juvenile salmonid behavior year-round in the immediate forebay surface layer of the WTC tower (within 20 m, depth 0-5 m). From October 28, 2010 through January 31, 2011 a BlueView acoustic camera was also deployed in an attempt to determine its usefulness for future studies as well as augment the DIDSON data. For the DIDSON data, we processed a total of 35 separate 24-h periods systematically covering every other week in the 12-month study. Two different 24-hour periods were processed for the BlueView data for the feasibility study. Juvenile salmonids were present in the immediate forebay of the WTC tower throughout 2010. The juvenile salmonid abundance index was low in the spring (<200 fish per sample-day), began increasing in late April and peaked in mid-May. Fish abundance index began decreasing in early June and remained low in the summer months. Fish abundance increased again in the fall, starting in October, and peaked on November 8-9. A second peak occurred on December 22. Afterwards, abundance was low for the rest of the study (through January 2011). Average fish length for juvenile salmonids during early spring 2010 was 214 {+-} 86 mm (standard deviation). From May through early November

Zooplankton Data - Ocean Survival of Salmonids

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — A study to evaluate the role of changing ocean conditions on growth and survival of juvenile salmon from the Columbia River basin as they enter the Columbia River...

Influence of riparian canopy on macroinvertebrate composition and food habits of juvenile salmonids in several Oregon streams.

Science.gov (United States)

William R. Meehan

1996-01-01

The community composition of macroinvertebrates and the feeding habits of juvenile salmonids were studied in eight Oregon streams. Benthic, drift, sticky trap, and water trap samples were taken over a 3-year period, along with stomach samples of the fish. Samples were taken in stream reaches with and without riparian canopy. Both main effects—fish diet versus...

Pathways of Barotrauma in Juvenile Salmonids Exposed to Simulated Hydroturbine Passage: Boyle’s Law vs. Henry’s Law

Energy Technology Data Exchange (ETDEWEB)

Brown, Richard S.; Pflugrath, Brett D.; Colotelo, Alison HA; Brauner, Colin J.; Carlson, Thomas J.; Deng, Zhiqun; Seaburg, Adam

2012-06-01

On their seaward migration, juvenile salmonids commonly pass hydroelectric dams. Fish passing by the turbine blade may experience rapid decompression, the severity of which can be highly variable and may result in a number of barotraumas. The mechanisms of these injuries can be due to expansion of existing bubbles or gases coming out of solution; governed by Boyle’s Law and Henry’s Law, respectively. This paper combines re-analysis of published data with new experiments to gain a better understanding of the mechanisms of injury and mortality for fish experiencing rapid decompression associated with hydroturbine passage. From these data it appears that the majority of decompression related injuries are due to the expansion of existing bubbles in the fish, particularly the expansion and rupture of the swim bladder. This information is particularly useful for fisheries managers and turbine manufacturers, demonstrating that reducing the rate of swim bladder ruptures by reducing the frequency of occurrence and severity of rapid decompression during hydroturbine passage could reduce the rates of injury and mortality for hydroturbine passed juvenile salmonids.

Status after 5 Years of Survival Compliance Testing in the Federal Columbia River Power System (FCRPS)

Energy Technology Data Exchange (ETDEWEB)

Skalski, John R.; Weiland, Mark A.; Ham, Kenneth D.; Ploskey, Gene R.; McMichael, Geoffrey A.; Colotelo, Alison H.; Carlson, Thomas J.; Woodley, Christa M.; Eppard, M. Brad; Hockersmith, Eric E.

2016-06-27

Survival studies of juvenile salmonids implanted with acoustic tags have been conducted at hydroelectric dams within the Federal Columbia River Power System (FCRPS) in the Columbia and Snake rivers between 2010 and 2014 to assess compliance with dam passage survival standards stipulated in the 2008 Biological Opinion (BiOp). For juvenile salmonids migrating downstream in the spring, dam passage survival defined as survival from the upstream dam face to the tailrace mixing zone must be ≥96% and for summer migrants, ≥93%, and estimated with a standard error ≤1.5% (i.e., 95% confidence interval of ±3%). A total of 29 compliance tests have been conducted at 6 of 8 FCRPS main-stem dams, using over 109,000 acoustic-tagged salmonid smolts. Of these 29 compliance studies, 23 met the survival standards and 26 met the precision requirements. Of the 6 dams evaluated to date, individual survival estimates range from 0.9597 to 0.9868 for yearling Chinook Salmon, 0.9534 to 0.9952 for steelhead, and 0.9076 to 0.9789 for subyearling Chinook Salmon. These investigations suggest the large capital investment over the last 20 years to improve juvenile salmon passage through the FCRPS dams has been beneficial.

Hydroacoustic Evaluation of Juvenile Salmonid Passage at The Dalles Dam in 2004

International Nuclear Information System (INIS)

Johnson, Gary E.; Hanks, Michael E.; Khan, Fenton; Cook, Chris B.; Hedgepeth, J.; Mueller, Robert P.; Rakowski, Cynthia L.; Richmond, Marshall C.; Sargeant, Susan L.; Serkowski, John A.; Skalski, John R.

2005-01-01

The U.S. Army Corps of Engineers Portland District engaged the Pacific Northwest National Laboratory to evaluate juvenile salmon passage at The Dalles Dam in 2004 to inform decisions about long-term measures and operations to enhance sluiceway and spill passage and reduce turbine passage to improve smolt survival at the dam. PNNL used fixed-location hydroacoustic sampling across the entire project, especially at the sluiceway and spillway, using multiple split-beam transducers at selected locations. At the sluiceway nearfield, we used an acoustic camera to track fish. The fish data were interpreted and integrated with hydraulic data from a CFD model and in-field ADCP measurements. Two sluiceway operations were compared: West only (SL 1) vs. West+East (SL 1 + SL 18). Based on our findings, we concluded that The Dalles Dam sluiceway has the potential to be highly efficient and effective at passing juvenile salmonids. This potential could be tapped with hydraulic and entrance enhancements to the sluiceway. We recommended the following: (1) six rather than three sluice gates should be opened to take advantage of the maximum hydraulic capacity of the sluiceway. (2) The turbine units below open sluice gates should be operated as a standard fish operations procedure. (3) In 2005, the Corps and fisheries agencies should consider operating sluice gates in one or more of the following combinations of six gates: (a) SL 1-1, 1-2, 1-3 and SL 18-1, 18-2, 18-3 (repeat 2004 operation), (b) SL 1-1, 1-2, 1-3 and SL 11-1, 11-2, 11-3, or (c) SL 1-1, 1-2, 1-3 and SL 2-1, 2-2, 2-3. The following elements for surface flow bypasses which should be considered during design of any sluiceway enhancements at The Dalles Dam: (1) form an extensive surface flow bypass flow net (surface bypass discharge greater than ∼7% of total project discharge), (2) create a gradual increase in water velocity approaching the surface flow bypass (ideally, acceleration 3 m/s) to entrain the subject juvenile

Significance of selective predation and development of prey protection measures for juvenile salmonids in the Columbia and Snake River reservoirs. Annual progress report, February 1993--February 1994

International Nuclear Information System (INIS)

Poe, T.P.

1994-01-01

This report addresses the problem of predator-prey interactions of juvenile salmonids in the Columbia and Snake River. Six papers are included on selective predation and prey protection. Attention is focused on monitoring the movements, the distribution, and the behavior of juvenile chinook salmon and northern squawfish

CTD Oceanographic Data - Ocean Survival of Salmonids

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — A study to evaluate the role of changing ocean conditions on growth and survival of juvenile salmon from the Columbia River basin as they enter the Columbia River...

Oceanographic Trawl Data - Ocean Survival of Salmonids

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — A study to evaluate the role of changing ocean conditions on growth and survival of juvenile salmon from the Columbia River basin as they enter the Columbia River...

A standard operating procedure for the surgical implantation of transmitters in juvenile salmonids

Science.gov (United States)

Liedtke, T.L.; Beeman, J.W.; Gee, L.P.

2012-01-01

Biotelemetry is a useful tool to monitor the movements of animals and is widely applied in fisheries research. Radio or acoustic technology can be used, depending on the study design and the environmental conditions in the study area. A broad definition of telemetry also includes the use of Passive Integrated Transponder (PIT) tags, either separately or with a radio or acoustic transmitter. To use telemetry, fish must be equipped with a transmitter. Although there are several attachment procedures available, surgical implantation of transmitters in the abdominal cavity is recognized as the best technique for long-term telemetry studies in general (Stasko and Pincock, 1977; Winter, 1996; Jepsen, 2003), and specifically for juvenile salmonids, Oncorhynchus spp. (Adams and others, 1998a, 1998b; Martinelli and others, 1998; Hall and others, 2009). Studies that use telemetry assume that the processes by which the animals are captured, handled, and tagged, as well as the act of carrying the transmitter, will have minimal effect on their behavior and performance. This assumption, commonly stated as a lack of transmitter effects, must be valid if telemetry studies are to describe accurately the movements and behavior of an entire population of interest, rather than the subset of that population that carries transmitters. This document describes a standard operating procedure (SOP) for surgical implantation of radio or acoustic transmitters in juvenile salmonids. The procedures were developed from a broad base of published information, laboratory experiments, and practical experience in tagging thousands of fish for numerous studies of juvenile salmon movements near Columbia River and Snake River hydroelectric dams. Staff from the Western Fisheries Research Center's Columbia River Research Laboratory (CRRL) frequently have used telemetry studies to evaluate new structures or operations at hydroelectric dams in the Columbia River Basin, and these evaluations typically

A synthesis of tagging studies examining the behaviour and survival of anadromous salmonids in marine environments.

Directory of Open Access Journals (Sweden)

S Matthew Drenner

Full Text Available This paper synthesizes tagging studies to highlight the current state of knowledge concerning the behaviour and survival of anadromous salmonids in the marine environment. Scientific literature was reviewed to quantify the number and type of studies that have investigated behaviour and survival of anadromous forms of Pacific salmon (Oncorhynchus spp., Atlantic salmon (Salmo salar, brown trout (Salmo trutta, steelhead (Oncorhynchus mykiss, and cutthroat trout (Oncorhynchus clarkii. We examined three categories of tags including electronic (e.g. acoustic, radio, archival, passive (e.g. external marks, Carlin, coded wire, passive integrated transponder [PIT], and biological (e.g. otolith, genetic, scale, parasites. Based on 207 papers, survival rates and behaviour in marine environments were found to be extremely variable spatially and temporally, with some of the most influential factors being temperature, population, physiological state, and fish size. Salmonids at all life stages were consistently found to swim at an average speed of approximately one body length per second, which likely corresponds with the speed at which transport costs are minimal. We found that there is relatively little research conducted on open-ocean migrating salmonids, and some species (e.g. masu [O. masou] and amago [O. rhodurus] are underrepresented in the literature. The most common forms of tagging used across life stages were various forms of external tags, coded wire tags, and acoustic tags, however, the majority of studies did not measure tagging/handling effects on the fish, tag loss/failure, or tag detection probabilities when estimating survival. Through the interdisciplinary application of existing and novel technologies, future research examining the behaviour and survival of anadromous salmonids could incorporate important drivers such as oceanography, tagging/handling effects, predation, and physiology.

Comparative evaluation of molecular diagnostic tests for Nucleospora salmonis and prevalence in migrating juvenile salmonids from the Snake River, USA

Science.gov (United States)

Badil, Samantha; Elliott, Diane G.; Kurobe, Tomofumi; Hedrick, Ronald P.; Clemens, Kathy; Blair, Marilyn; Purcell, Maureen K.

2011-01-01

Nucleospora salmonis is an intranuclear microsporidian that primarily infects lymphoblast cells and contributes to chronic lymphoblastosis and a leukemia-like condition in a range of salmonid species. The primary goal of this study was to evaluate the prevalence of N. salmonis in out-migrating juvenile hatchery and wild Chinook salmon Oncorhynchus tshawytscha and steelhead O. mykiss from the Snake River in the U.S. Pacific Northwest. To achieve this goal, we first addressed the following concerns about current molecular diagnostic tests for N. salmonis: (1) nonspecific amplification patterns by the published nested polymerase chain reaction (nPCR) test, (2) incomplete validation of the published quantitative PCR (qPCR) test, and (3) whether N. salmonis can be detected reliably from nonlethal samples. Here, we present an optimized nPCR protocol that eliminates nonspecific amplification. During validation of the published qPCR test, our laboratory developed a second qPCR test that targeted a different gene sequence and used different probe chemistry for comparison purposes. We simultaneously evaluated the two different qPCR tests for N. salmonis and found that both assays were highly specific, sensitive, and repeatable. The nPCR and qPCR tests had good overall concordance when DNA samples derived from both apparently healthy and clinically diseased hatchery rainbow trout were tested. Finally, we demonstrated that gill snips were a suitable tissue for nonlethal detection of N. salmonis DNA in juvenile salmonids. Monitoring of juvenile salmonid fish in the Snake River over a 3-year period revealed low prevalence of N. salmonis in hatchery and wild Chinook salmon and wild steelhead but significantly higher prevalence in hatchery-derived steelhead. Routine monitoring of N. salmonis is not performed for all hatchery steelhead populations. At present, the possible contribution of this pathogen to delayed mortality of steelhead has not been determined.

Quantifying the effect of predators on endangered species using a bioenergetics approach : Caspian terns and juvenile salmonids in the Columbia River estuary

NARCIS (Netherlands)

Roby, DD; Lyons, DE; Craig, DP; Collis, K; Visser, GH

We estimated the consumption of juvenile salmonids (Oncorhynchus spp.) and other forage fishes by Caspian terns (Sterna caspia) nesting on Rice Island in the Columbia River estuary in 1997 and 1998 using a bioenergetics modeling approach. The study was prompted by concern that Caspian tern predation

Hydroacoustic Evaluation of Juvenile Salmonid Passage at The Dalles Dam in 2004

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Hanks, Michael E.; Khan, Fenton; Cook, Chris B.; Hedgepeth, J; Mueller, Robert P.; Rakowski, Cynthia L.; Richmond, Marshall C.; Sargeant, Susan L.; Serkowski, John A.; Skalski, John R.

2005-06-01

The U.S. Army Corps of Engineers Portland District engaged the Pacific Northwest National Laboratory to evaluate juvenile salmon passage at The Dalles Dam in 2004 to inform decisions about long-term measures and operations to enhance sluiceway and spill passage and reduce turbine passage to improve smolt survival at the dam. PNNL used fixed-location hydroacoustic sampling across the entire project, especially at the sluiceway and spillway, using multiple split-beam transducers at selected locations. At the sluiceway nearfield, we used an acoustic camera to track fish. The fish data were interpreted and integrated with hydraulic data from a CFD model and in-field ADCP measurements. Two sluiceway operations were compared: West only (SL 1) vs. West+East (SL 1 + SL 18). Based on our findings, we concluded that The Dalles Dam sluiceway has the potential to be highly efficient and effective at passing juvenile salmonids. This potential could be tapped with hydraulic and entrance enhancements to the sluiceway. We recommended the following: (1) six rather than three sluice gates should be opened to take advantage of the maximum hydraulic capacity of the sluiceway. (2) The turbine units below open sluice gates should be operated as a standard fish operations procedure. (3) In 2005, the Corps and fisheries agencies should consider operating sluice gates in one or more of the following combinations of six gates: (a) SL 1-1, 1-2, 1-3 and SL 18-1, 18-2, 18-3 (repeat 2004 operation), (b) SL 1-1, 1-2, 1-3 and SL 11-1, 11-2, 11-3, or (c) SL 1-1, 1-2, 1-3 and SL 2-1, 2-2, 2-3. The following elements for surface flow bypasses which should be considered during design of any sluiceway enhancements at The Dalles Dam: (1) form an extensive surface flow bypass flow net (surface bypass discharge greater than {approx}7% of total project discharge), (2) create a gradual increase in water velocity approaching the surface flow bypass (ideally, acceleration < 1 m/s/m), (3) make water

System-Wide Significance of Predation on Juvenile Salmonids in Columbia and Snake River Reservoirs : Annual Report 1992.

Energy Technology Data Exchange (ETDEWEB)

Petersen, James H.; Poe, Thomas P.

1993-12-01

Northern squawfish (Ptychocheilus oregonensis) predation on juvenile salmonids was characterized during 1992 at ten locations in the Columbia River below Bonneville Dam and at three locations in John Day Reservoir. During the spring and summer, 1,487 northern squawfish were collected in the lower Columbia River and 202 squawfish were sampled in John Day Reservoir. Gut content data, predator weight, and water temperature were used to compute a consumption index (CI) for northern squawfish, and overall diet was also described. In the Columbia River below Bonneville Dam, northern squawfish diet was primarily fish (spring 69%; summer 53%), most of which were salmonids. Salmonids were also the primary diet component in the Bonneville Dam tailrace, John Day Dam forebay, and the McNary Dam tailrace. Crustaceans were the dominant diet item at the John Day mid-reservoir location, although sample sizes were small. About half of the non-salmonid preyfish were sculpins. The consumption index (CI) of northern squawfish was generally higher during summer than during spring. The highest CI`s were observed during summer in the tailrace boat restricted zones of Bonneville Dam (CI = 7.8) and McNary Dam (CI = 4.6). At locations below Bonneville Dam, CI`s were relatively low near Covert`s Landing and Rooster Rock, higher at four locations between Blue Lake and St. Helens, and low again at three downriver sites (Kalama, Ranier, and Jones Beach). Northern squawfish catches and CI`s were noticeably higher throughout the lower Columbia compared to mid-reservoir sites further upriver sampled during 1990--92. Predation may be especially intense in the free-flowing section of the Columbia River below Bonneville Dam. Smallmouth bass (Micropterus dolomieui; N = 198) ate mostly fish -- 25% salmonids, 29% sculpins, and 46% other fish. Highest catches of smallmouth bass were in the John Day Dam forebay.

Patterns of coho salmon size and survival within a stream network

Science.gov (United States)

Effective habitat restoration planning requires correctly anticipating demographic responses to altered habitats. Network-scale investigations of habitat-specific growth and survival of juvenile salmonids have provided critical insights that can now better inform and help priori...

Bird Distribution and Abundance - Ocean Survival of Salmonids

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — A study to evaluate the role of changing ocean conditions on growth and survival of juvenile salmon from the Columbia River basin as they enter the Columbia River...

A multi-year analysis of passage and survival at McNary Dam, 2004-09

Science.gov (United States)

Adams, Noah S.; Walker, C.E.; Perry, R.W.

2011-01-01

We analyzed 6 years (2004–09) of passage and survival data collected at McNary Dam to determine how dam operations and environmental conditions affect passage and survival of juvenile salmonids. A multinomial logistic regression was used to examine how environmental variables and dam operations relate to passage behavior of juvenile salmonids at McNary Dam. We used the Cormack-Jolly-Seber release-recapture model to determine how the survival of juvenile salmonids passing through McNary Dam relates to environmental variables and dam operations. Total project discharge and the proportion of flow passing the spillway typically had a positive effect on survival for all species and routes. As the proportion of water through the spillway increased, the number of fish passing the spillway increased, as did overall survival. Additionally, survival generally was higher at night. There was no meaningful difference in survival for fish that passed through the north or south portions of the spillway or powerhouse. Similarly, there was no difference in survival for fish released in the north, middle, or south portions of the tailrace. For subyearling Chinook salmon migrating during the summer season, increased temperatures had a drastic effect on passage and survival. As temperature increased, survival of subyearling Chinook salmon decreased through all passage routes and the number of fish that passed through the turbines increased. During years when the temporary spillway weirs (TSWs) were installed, passage through the spillway increased for spring migrants. However, due to the changes made in the location of the TSW between years and the potential effect of other confounding environmental conditions, it is not certain if the increase in spillway passage was due solely to the presence of the TSWs. The TSWs appeared to improve forebay survival during years when they were operated.

The design and analysis of salmonid tagging studies in the Columbia Basin. Volume 2: Estimating salmonid survival with combined PIT-CWT tagging. Technical report

International Nuclear Information System (INIS)

Newman, K.

1997-06-01

Passive Integrated Transponder (PIT) tags and Coded Wire Tags (CWTs) in combination can provide information about salmonid survival that single tag releases may not. The release and recapture protocol affects which survival and recapture rates can be estimated and the precision of the estimates. For the particular case of Columbia river salmonids tagged with both PIT tags and CWTs, three different release and recapture protocols were evaluated. This report addresses the need to study the fate of salmon smolt in-river and their subsequent return as adults. Double-tagging procedures are investigated where PIT-tags would be used to provide in-river survival data during smolt outmigrations and coded-wire tags (CWT) used to provide adult return information. This report provides statistical models for the analysis of the joint data as well as recommendations on optimal tagging studies. Study costs and stress on smolt can be reduced by only PIT-tagging a subset of all the fish coded-wire-tagged, while retaining the information content and sampling precision

Adaptive trade-offs in juvenile salmonid metabolism associated with habitat partitioning between coho salmon and steelhead trout in coastal streams.

Science.gov (United States)

Van Leeuwen, Travis E; Rosenfeld, Jordan S; Richards, Jeffrey G

2011-09-01

1. Adaptive trade-offs are fundamental to the evolution of diversity and the coexistence of similar taxa and occur when complimentary combinations of traits maximize efficiency of resource exploitation or survival at different points on environmental gradients. 2. Standard metabolic rate (SMR) is a key physiological trait that reflects adaptations to baseline metabolic performance, whereas active metabolism reflects adaptations to variable metabolic output associated with performance related to foraging, predator avoidance, aggressive interactions or migratory movements. Benefits of high SMR and active metabolism may change along a resource (productivity) gradient, indicating that a trade-off exists among active metabolism, resting metabolism and energy intake. 3. We measured and compared SMR, maximal metabolic rate (MMR), aerobic scope (AS), swim performance (UCrit) and growth of juvenile hatchery and wild steelhead and coho salmon held on high- and low-food rations in order to better understand the potential significance of variation in SMR to growth, differentiation between species, and patterns of habitat use along a productivity gradient. 4. We found that differences in SMR, MMR, AS, swim performance and growth rate between steelhead trout and coho salmon were reduced in hatchery-reared fish compared with wild fish. Wild steelhead had a higher MMR, AS, swim performance and growth rate than wild coho, but adaptations between species do not appear to involve differences in SMR or to trade-off increased growth rate against lower swim performance, as commonly observed for high-growth strains. Instead, we hypothesize that wild steelhead may be trading off higher growth rate for lower food consumption efficiency, similar to strategies adopted by anadromous vs. resident brook trout and Atlantic salmon vs. brook trout. This highlights potential differences in food consumption and digestion strategies as cryptic adaptations ecologically differentiating salmonid species

Relationship of otolith strontium-to-calcium ratios and salinity: Experimental validation for juvenile salmonids

Science.gov (United States)

Zimmerman, C.E.

2005-01-01

Analysis of otolith strontium (Sr) or strontium-to-calcium (Sr:Ca) ratios provides a powerful tool to reconstruct the chronology of migration among salinity environments for diadromous salmonids. Although use of this method has been validated by examination of known individuals and translocation experiments, it has never been validated under controlled experimental conditions. In this study, incorporation of otolith Sr was tested across a range of salinities and resulting levels of ambient Sr and Ca concentrations in juvenile chinook salmon (Oncorhynchus tshawytscha), coho salmon (Oncorhynchus kisutch), sockeye salmon (Oncorhynchus nerka), rainbow trout (Oncorhynchus rnykiss), and Arctic char (Salvelinus alpinus). Experimental water was mixed, using stream water and seawater as end members, to create experimental salinities of 0.1, 6.3, 12.7, 18.6, 25.5, and 33.0 psu. Otolith Sr and Sr:Ca ratios were significantly related to salinity for all species (r2 range: 0.80-0.91) but provide only enough predictive resolution to discriminate among fresh water, brackish water, and saltwater residency. These results validate the use of otolith Sr:Ca ratios to broadly discriminate salinity histories encountered by salmonids but highlight the need for further research concerning the influence of osmoregulation and physiological changes associated with smoking on otolith microchemistry.

Rates of consumption of juvenile salmonids and alternative prey fish by northern squawfish, walleyes, smallmouth bass, and channel catfish in John Day Reservoir, Columbia River

International Nuclear Information System (INIS)

Vigg, S.; Poe, T.P.; Prendergast, L.A.; Hansel, H.C.

1991-01-01

Adult northern squawfish Ptychocheilus oregonesis, walleyes Stizostedion vitreum, smallmouth bass Micropterus dolomieu, and channel catfish Ictalurus punctatus were sampled from four regions of John Day Reservoir from April to August 1983-1986 to quantify their consumption of 13 species of prey fish, particularly seaward-migrating juvenile Pacific salmon and steelhead (Oncorhynchus spp.). Consumption rates were estimated from field data on stomach contents and digestion rate relations determined in previous investigations. For each predator, consumption rates varied by reservoir area, month, time of day, and predator size or age. The greatest daily consumption of salmonids by northern squawfish and channel catfish occurred in the upper end of the reservoir below McNary Dam. Greatest daily predation by walleyes and smallmouth bass occurred in the middle and lower reservoir. Consumption rates of all predators were highest in July, concurrent with maximum temperature and abundance of juvenile salmonids. Feeding by the predators tended to peak after dawn and near midnight. Northern squawfish below McNary Dam exhibited this pattern, but fed mainly in the morning hours down-reservoir. The daily ration of total prey fish was highest for northern squawfish over 451 mm fork length, for walleyes 201-250 mm, for smallmouth bass 176-200 mm, and for channel catfish 401-450 mm. Averaged over all predator sizes and sampling months (April-August), the total daily ration (fish plus other prey) of smallmouth bass was about twice that of channel catfish, northern squawfish, and walleyes. However, northern squawfish was clearly the major predator on juvenile salmonids

Hydroacoustic Evaluation of Juvenile Salmonid Passage and Distribution at Lookout Point Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Johnson, Gary E.; Royer, Ida M.; Hughes, James S.; Fischer, Eric S.; Trott, Donna M.; Ploskey, Gene R.

2012-05-31

Pacific Northwest National Laboratory evaluated juvenile salmonid passage and distribution at Lookout Point Dam (LOP) on the Middle Fork Willamette River for the U.S. Army Corps of Engineers, Portland District (USACE), to provide data to support decisions on long-term measures to enhance downstream passage at LOP and others dams in USACE's Willamette Valley Project. This study was conducted in response to the listing of Upper Willamette River Spring Chinook salmon (Oncorhynchus tshawytscha) and Upper Willamette River steelhead (O. mykiss) as threatened under the Endangered Species Act. We conducted a hydroacoustic evaluation of juvenile salmonid passage and distribution at LOP during February 2010 through January 2011. Findings from this 1 year of study should be applied carefully because annual variation can be expected due to variability in adult salmon escapement, egg-to-fry and fry-to-smolt survival rates, reservoir rearing and predation, dam operations, and weather. Fish passage rates for smolt-size fish (> {approx}90 mm and < 300 mm) were highest during December-January and lowest in mid-summer through early fall. Passage peaks were also evident in early spring, early summer, and late fall. During the entire study period, an estimated total of 142,463 fish {+-} 4,444 (95% confidence interval) smolt-size fish passed through turbine penstock intakes. Of this total, 84% passed during December-January. Run timing for small-size fish ({approx}65-90 mm) peaked (702 fish) on December 18. Diel periodicity of smolt-size fish showing crepuscular peaks was evident in fish passage into turbine penstock intakes. Relatively few fish passed into the Regulating Outlets (ROs) when they were open in summer (2 fish/d) and winter (8 fish/d). Overall, when the ROs were open, RO efficiency (RO passage divided by total project passage) was 0.004. In linear regression analyses, daily fish passage (turbines and ROs combined) for smolt-size fish was significantly related to

Predation by Northern Pikeminnow and tiger muskellunge on juvenile salmonids in a high–head reservoir: Implications for anadromous fish reintroductions

Science.gov (United States)

Sorel, Mark H.; Hansen, Adam G.; Connelly, Kristin A.; Wilson, Andrew C.; Lowery, Erin D.; Beauchamp, David A.

2016-01-01

salmonids. This study highlights the importance of evaluating trophic interactions within reservoirs slated for reintroduction with anadromous salmonids, as they can be functional migration corridors and may offer profitable juvenile-rearing habitats despite hosting abundant predator populations.

Hydroacoustic Evaluation of Juvenile Salmonid Passage and Distribution at Lookout Point Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Johnson, Gary E.; Royer, Ida M.; Hughes, James S.; Fischer, Eric S.; Trott, Donna M.; Ploskey, Gene R.

2011-07-01

This report presents the results of an evaluation of juvenile salmonid passage and distribution at Lookout Point Dam (LOP) on the Middle Fork Willamette River. The study was conducted by the Pacific Northwest National Laboratory for the U.S. Army Corps of Engineers, Portland District (USACE). The goal of the study was to provide fish passage and distribution data to support decisions on long-term measures to enhance downstream passage at LOP and others dams in USACE’s Willamette Valley Project in response to the listing of Upper Willamette River Spring Chinook salmon (Oncorhynchus tshawytscha) and Upper Willamette River steelhead (O. mykiss) as threatened under the Endangered Species Act. During the year-long study period - February 1, 2010 to January 31, 2011the objectives of the hydroacoustic evaluation of fish passage and distribution at LOP were to: 1. Estimate passage rates, run timing, horizontal distribution, and diel distribution at turbine penstock intakes for smolt-size fish. 2. Estimate passage rates, run timing and diel distribution at turbine penstock intakes for small-size fish. 3. Estimate passage rates and run timing at the regulating outlets for smolt-size fish. 4. Estimate vertical distribution of smolt-size fish in the forebay near the upstream face of the dam. The fixed-location hydroacoustic technique was used to accomplish the objectives of this study. Transducers (420 kHz) were deployed in each penstock intake, above each RO entrance, and on the dam face; a total of nine transducers (2 single-beam and 7 split-beam) were used. We summarize the findings from the hydroacoustic evaluation of juvenile salmonid passage and distribution at LOP during February 2010 through January 2011 as follows. • Fish passage rates for smolt-size fish (> ~90 mm) were highest during December-January and lowest in mid-summer through early fall. • During the entire study period, an estimated total of 142,463 fish ± 4,444 (95% confidence interval) smolt

Research, Monitoring, and Evaluation of Avian Predation on Salmonid Smolts in the Lower and Mid-Columbia River, 2006 Final Season Summary.

Energy Technology Data Exchange (ETDEWEB)

Roby, Daniel D. [USGS - Oregon Cooperative Fish and Wildlife Research Unit, Oregon State University; Collis, Ken [Real Time Research, Inc.; Lyons, Donald E. [USGS - Oregon Cooperative Fish and Wildlife Research Unit, Oregon State University

2009-06-18

This study investigates predation by piscivorous waterbirds on juvenile salmonids (Oncorhynchus spp.) from throughout the Columbia River Basin. During 2006, study objectives in the Columbia River estuary, work funded by the Bonneville Power Administration, were to (1) monitor and evaluate previous management initiatives to reduce Caspian tern (Hydroprogne caspia) predation on juvenile salmonids (smolts); (2) measure the impact of double-crested cormorant (Phalacrocorax auritus) predation on smolt survival, and assess potential management options to reduce cormorant predation; and (3) monitor large colonies of other piscivorous waterbirds in the estuary (i.e., glaucous-winged/western gulls [Larus glaucescens/occidentalis]) to determine the potential impacts on smolt survival. Study objectives on the mid-Columbia River, work funded by the Walla Walla District of the U.S. Army Corps of Engineers, were to (1) measure the impact of predation by Caspian terns and double-crested cormorants on smolt survival; and (2) monitor large nesting colonies of other piscivorous waterbirds (i.e., California gulls [L. californicus], ring-billed gulls [L. delawarensis], American white pelicans [Pelecanus erythrorhynchos]) on the mid-Columbia River to determine the potential for significant impacts on smolt survival. Our efforts to evaluate system-wide losses of juvenile salmonids to avian predation indicated that Caspian terns and double-crested cormorants were responsible for the vast majority of smolt losses to avian predators in the Columbia Basin, with most losses occurring in the Columbia River estuary. In 2006, East Sand Island in the Columbia River estuary supported the largest known breeding colonies of Caspian terns and double-crested cormorants in the world. The Caspian tern colony on East Sand Island consisted of about 9,200 breeding pairs in 2006, up slightly (but not significantly so) from the estimate of colony size in 2005 (8,820 pairs). There has not been a

Dependent vs. independent juvenile survival: contrasting drivers of variation and the buffering effect of parental care.

Science.gov (United States)

Dybala, Kristen E; Gardali, Thomas; Eadie, John M

2013-07-01

Juvenile survival is often found to be more sensitive than adult survival to variation in environmental conditions, and variation in juvenile survival can have significant impacts on population growth rates and viability. Therefore, understanding the population-level effects of environmental changes requires understanding the effects on juvenile survival. We hypothesized that parental care will buffer the survival of dependent juveniles from variation in environmental conditions, while the survival of independent juveniles will respond more strongly to environmental variation and, in turn, drive the overall variation in annual juvenile survival. We tested this parental-care hypothesis using a 30-year mark-recapture data set to model the survival of juvenile Song Sparrows (Melospiza melodia) during the dependent and independent stages. We examined the effects of weather, density, and cohort mean fledge date and body mass on annual variation in survival during the first 12 weeks after fledging, as well as effects of individual fledge date and body mass on individual variation in survival. The primary driver of annual variation in juvenile survival was precipitation during the previous rainy season, consistent with an effect on food availability, which had a strong positive effect on the survival of independent juveniles, but no effect on dependent juveniles. We also found strong support for effects of body mass and fledge date on individual survival probability, including striking differences in the effect of fledge date by stage. Our results provided evidence that different mechanisms influence juvenile survival during each stage of fledgling development, and that parental care buffers the survival of dependent juveniles from variation in environmental conditions. Consequently, variation in juvenile survival was driven by independent juveniles, not dependent juveniles, and studies focused only on survival during the dependent stage may not be able to detect the

Occurrence and significance of atypical Aeromonas salmonicida in non-salmonid and salmonid fish species : A review

DEFF Research Database (Denmark)

Wiklund, T.; Dalsgaard, Inger

1998-01-01

, non-salmonids as well as salmonids, inhabiting fresh water, brackish water and marine environments in northern and central Europe, South Africa, North America, Japan and Australia. In non-salmonid fish species, infections with atypical strains often manifest themselves as superficial skin ulcerations...... information is available about the ecology, spread and survival of atypical strains in water. The commonly used therapeutic methods for the control of diseases in farmed fish caused by atypical A. salmonicida are generally effective against the atypical strains. Resistance to different antibiotics...

AFSC/ABL: Juvenile rockfish DNA species identification

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Many pelagic juvenile rockfish (Sebastes) were collected in juvenile salmonid surveys in the Gulf of Alaska (GOA) from 1998 to 2002. Often species identification of...

Characterization of Gatewell Orifice Lighting at the Bonneville Dam Second Powerhouse and Compendium of Research on Light Guidance with Juvenile Salmonids

Energy Technology Data Exchange (ETDEWEB)

Mueller, Robert P.; Simmons, Mary Ann

2007-12-29

The goal of the study described in this report is to provide U.S. Army Corps of Engineers (USACE) biologists and engineers with general design guidelines for using artificial lighting to enhance the passage of juvenile salmonids into the collection channel at the Bonneville Dam second powerhouse (B2). During fall 2007, Pacific Northwest National Laboratory (PNNL) researchers measured light levels in the field at one powerhouse orifice through which fish must pass to reach the collection channel. Two light types were evaluated—light-emitting diode (LED) lights and halogen spot lights. Additional measurements with mercury lamps were made at the PNNL Aquatic Research Laboratory to determine baseline intensity of the current lighting. A separate chapter synthesizes the relevant literature related to light and fish guidance for both field and laboratory studies. PNNL will also review the Corps plans for existing lighting protocol at all of the Portland District projects and help develop a uniform lighting scheme which could be implemented. The specific objectives for this study are to 1. Create a synthesis report of existing lighting data for juvenile salmonid attraction and deterrence and how the data are used at fish bypass facilities. 2. Evaluate current B2 orifice lighting conditions with both LED and halogen sources. 3. Make recommendations as to what lighting intensity, source, and configuration would improve passage at the B2 orifices. 4. Review USACE plans for retrofit of existing systems (to be assessed at a later date).

A field evaluation of an external and neutrally buoyant acoustic transmitter for juvenile salmon: implications for estimating hydroturbine passage survival.

Directory of Open Access Journals (Sweden)

Richard S Brown

Full Text Available Turbine-passed fish are exposed to rapid decreases in pressure which can cause barotrauma. The presence of an implanted telemetry tag increases the likelihood of injury or death from exposure to pressure changes, thus potentially biasing studies evaluating survival of turbine-passed fish. Therefore, a neutrally buoyant externally attached tag was developed to eliminate this bias in turbine passage studies. This new tag was designed not to add excess mass in water or take up space in the coelom, having an effective tag burden of zero with the goal of reducing pressure related biases to turbine survival studies. To determine if this new tag affects fish performance or susceptibility to predation, it was evaluated in the field relative to internally implanted acoustic transmitters (JSATS; Juvenile Salmon Acoustic Telemetry System used widely for survival studies of juvenile salmonids. Survival and travel time through the study reach was compared between fish with either tag type in an area of high predation in the Snake and Columbia rivers, Washington. An additional group of fish affixed with neutrally-buoyant dummy external tags were implanted with passive integrated transponder (PIT tags and recovered further downstream to assess external tag retention and injury. There were no significant differences in survival to the first detection site, 12 river kilometers (rkm downstream of release. Travel times were also similar between groups. Conversely, externally-tagged fish had reduced survival (or elevated tag loss to the second detection site, 65 rkm downstream. In addition, the retention study revealed that tag loss was first observed in fish recaptured approximately 9 days after release. Results suggest that this new tag may be viable for short term (<8 days single-dam turbine-passage studies and under these situations, may alleviate the turbine passage-related bias encountered when using internal tags, however further research is needed to

A field evaluation of an external and neutrally buoyant acoustic transmitter for juvenile salmon: implications for estimating hydroturbine passage survival.

Science.gov (United States)

Brown, Richard S; Deng, Z Daniel; Cook, Katrina V; Pflugrath, Brett D; Li, Xinya; Fu, Tao; Martinez, Jayson J; Li, Huidong; Trumbo, Bradly A; Ahmann, Martin L; Seaburg, Adam G

2013-01-01

Turbine-passed fish are exposed to rapid decreases in pressure which can cause barotrauma. The presence of an implanted telemetry tag increases the likelihood of injury or death from exposure to pressure changes, thus potentially biasing studies evaluating survival of turbine-passed fish. Therefore, a neutrally buoyant externally attached tag was developed to eliminate this bias in turbine passage studies. This new tag was designed not to add excess mass in water or take up space in the coelom, having an effective tag burden of zero with the goal of reducing pressure related biases to turbine survival studies. To determine if this new tag affects fish performance or susceptibility to predation, it was evaluated in the field relative to internally implanted acoustic transmitters (JSATS; Juvenile Salmon Acoustic Telemetry System) used widely for survival studies of juvenile salmonids. Survival and travel time through the study reach was compared between fish with either tag type in an area of high predation in the Snake and Columbia rivers, Washington. An additional group of fish affixed with neutrally-buoyant dummy external tags were implanted with passive integrated transponder (PIT) tags and recovered further downstream to assess external tag retention and injury. There were no significant differences in survival to the first detection site, 12 river kilometers (rkm) downstream of release. Travel times were also similar between groups. Conversely, externally-tagged fish had reduced survival (or elevated tag loss) to the second detection site, 65 rkm downstream. In addition, the retention study revealed that tag loss was first observed in fish recaptured approximately 9 days after release. Results suggest that this new tag may be viable for short term (<8 days) single-dam turbine-passage studies and under these situations, may alleviate the turbine passage-related bias encountered when using internal tags, however further research is needed to confirm this.

Coastal coho salmon research in the West Fork Smith River: Patterns of coho salmon size and survival within a complex watershed

Science.gov (United States)

Effective habitat restoration planning requires the ability to anticipate fish population responses to altered habitats. The EPA has conducted network-scale research to document habitat-specific growth and survival of juvenile salmonids in a complex watershed. These findings ha...

Effects of natal departure and water level on survival of juvenile snail kites (Rostrhamus sociabilis) in Florida

Science.gov (United States)

Dreitz, V.J.; Kitchens, W.M.; DeAngelis, D.L.

2004-01-01

Survival rate from fledging to breeding, or juvenile survival, is an important source of variation in lifetime reproductive success in birds. Therefore, determining the relationship between juvenile survival and environmental factors is essential to understanding fitness consequences of reproduction in many populations. With increases in density of individuals and depletion of food resources, quality of most habitats deteriorates during the breeding season. Individuals respond by dispersing in search of food resources. Therefore, to understand the influence of environmental factors on juvenile survival, it is also necessary to know how natal dispersal influences survival of juveniles. We examined effects of various environmental factors and natal dispersal behavior on juvenile survival of endangered Snail Kites (Rostrhamus sociabilis) in central and southern Florida, using a generalized estimating equations (GEEs) approach and model selection criteria. Our results suggested yearly effects and an influence of age and monthly minimum hydrologic levels on juvenile Snail Kite survival. Yearly variation in juvenile survival has been reported by other studies, and other reproductive components of Snail Kites also exhibit such variation. Age differences in juvenile survival have also been seen in other species during the juvenile period. Our results demonstrate a positive relationship between water levels and juvenile survival. We suggest that this is not a direct linear relationship, such that higher water means higher juvenile survival. The juvenile period is concurrent with onset of the wet season in the ecosystem we studied, and rainfall increases as juveniles age. For management purposes, we believe that inferences suggesting increasing water levels during the fledging period will increase juvenile survival may have short-term benefits but lead to long-term declines in prey abundance and possibly wetland vegetation structure.

The impact of the Sea Empress oil spill on the abundance of juvenile migratory salmonids in West Wales

International Nuclear Information System (INIS)

Roberts, D.E.; Jones, F.H.; Wyatt, R.J.; Milner, N.J.

1998-01-01

No counting facilities for adult salmonids were operational in the rivers draining into the area of coast affected by the Sea Empress oil spill. There were therefore no direct means of determining any impact on the numbers of returning salmon and sea trout. However, a measure of salmon and trout fry abundance before and after (1997) the spill may provide evidence of an impact; on recruitment and abundance of adults. Approximately 10 years historical fry data were available from 53 sites on the Tywi and 41 sites on the Taf, as part of the Welsh Region Juvenile Salmonid Monitoring Programme (RJSMP). An assessment was undertaken by the Water Research Centre on the design of the survey and appropriate data analysis. Analysed data included: River Tywi salmon and trout fry densities 1985-1996, compared to 1997 and Teifi control 1986-1997. River Taf salmon and trout fry densities 1986-1996, compared to 1997 and Teifi control 1986-1997. The abundance of salmon and trout fry in 1997 were similar to previous years suggesting the Sea Empress oil spill did not have a major impact on recruitment. However, it is not possible to conclude unequivocally that returning salmon and sea trout were not affected by the spill. (author)

Survival Estimates for the Passage of Juvenile Chinook Salmon through Snake River Dams and Reservoirs, 1993 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Iwamoto, Robert N.; Sandford, Benjamin P.; McIntyre, Kenneth W.

1994-04-01

A pilot study was conducted to estimate survival of hatchery-reared yearling chinook salmon through dams and reservoirs on the Snake River. The goals of the study were to: (1) field test and evaluate the Single-Release, Modified-Single-Release, and Paired-Release Models for the estimation of survival probabilities through sections of a river and hydroelectric projects; (2) identify operational and logistical constraints to the execution of these models; and (3) determine the usefulness of the models in providing estimates of survival probabilities. Field testing indicated that the numbers of hatchery-reared yearling chinook salmon needed for accurate survival estimates could be collected at different areas with available gear and methods. For the primary evaluation, seven replicates of 830 to 1,442 hatchery-reared yearling chinook salmon were purse-seined from Lower Granite Reservoir, PIT tagged, and released near Nisqually John boat landing (River Kilometer 726). Secondary releases of PIT-tagged smolts were made at Lower Granite Dam to estimate survival of fish passing through turbines and after detection in the bypass system. Similar secondary releases were made at Little Goose Dam, but with additional releases through the spillway. Based on the success of the 1993 pilot study, the authors believe that the Single-Release and Paired-Release Models will provide accurate estimates of juvenile salmonid passage survival for individual river sections, reservoirs, and hydroelectric projects in the Columbia and Snake Rivers.

Survival estimates for the passage of juvenile chinook salmon through Snake River dams and reservoirs. Annual report 1993

International Nuclear Information System (INIS)

Iwamoto, R.N.; Muir, W.D.; Sandford, B.P.; McIntyre, K.W.; Frost, D.A.; Williams, J.G.; Smith, S.G.; Skalski, J.R.

1994-04-01

A pilot study was conducted to estimate survival of hatchery-reared yearling chinook salmon through dams and reservoirs on the Snake River. The goals of the study were to: (1) field test and evaluate the Single-Release, Modified-Single-Release, and Paired-Release Models for the estimation of survival probabilities through sections of a river and hydroelectric projects; (2) identify operational and logistical constraints to the execution of these models; and (3) determine the usefulness of the models in providing estimates of survival probabilities. Field testing indicated that the numbers of hatchery-reared yearling chinook salmon needed for accurate survival estimates could be collected at different areas with available gear and methods. For the primary evaluation, seven replicates of 830 to 1,442 hatchery-reared yearling chinook salmon were purse-seined from Lower Granite Reservoir, PIT tagged, and released near Nisqually John boat landing (River Kilometer 726). Secondary releases of PIT-tagged smolts were made at Lower Granite Dam to estimate survival of fish passing through turbines and after detection in the bypass system. Similar secondary releases were made at Little Goose Dam, but with additional releases through the spillway. Based on the success of the 1993 pilot study, the authors believe that the Single-Release and Paired-Release Models will provide accurate estimates of juvenile salmonid passage survival for individual river sections, reservoirs, and hydroelectric projects in the Columbia and Snake Rivers

Development of an Index to Bird Predation of Juvenile Salmonids within the Yakima River, 1999 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Gassley, James M.; Grue, Christian E. (University of Washington, School of Aquatic and Fishery Sciences, Seattle, WA)

2001-10-01

Avian predation of fish is suspected to contribute to the loss of juvenile spring chinook salmon in the Yakima Basin, potentially constraining natural production. In 1997 and 1998, the Yakama/Klickitat Fisheries Project (YKFP) and the Washington Department of Fish and Wildlife (WDFW)--whose goal is to increase natural production historically present within the Yakima River--initiated investigations to assess the feasibility of developing an index to avian predation of juvenile salmon within the river. This research--conducted by Dr. Steve Mathews and David Phinney of the University of Washington--confirmed that Ring-billed Gulls and Common Mergansers were the primary avian predators of juvenile salmon, and that under certain conditions could significantly impact migrating smolt populations. Beginning in 1999, the Washington Cooperative Fish and Wildlife Research Unit was asked by the YKFP and the WDFW to continue development of avian consumption indices. Monitoring methods developed by Mathews and Phinney were adopted (with modifications) and monitoring of impacts to juvenile salmon along river reaches and at areas of high predator/prey concentrations (colloquially referred to as ''hotspots'') continued. New efforts initiated in 1999 included piscivorous bird surveys at smolt acclimation sites operated by the Yakama Nation, monitoring of the North Fork Teanaway River for changes in avian piscivore abundance associated with the installation of the Jack Creek acclimation facility, and aerial surveys seeking to identify avian piscivores along the length of the Yakima River. In 1999, piscivorous birds were counted from river banks at hotspots and from a raft or drift boat along river reaches. Consumption by gulls was based on direct observations of foraging success and modeled abundance; consumption by Common Mergansers (which forage underwater) was estimated using published dietary requirements and modeled abundance. A second-order polynomial

System-wide significance of predation on juvenile salmonids in Columbia and Snake River reservoirs and evaluation of predation control measures. Annual report 1993

International Nuclear Information System (INIS)

Gadomski, D.M.; Poe, T.P.

1994-01-01

This project had three major goals. The first was to assist the Oregon Department of Fish and Wildlife with predation indexing as part of an effort to estimate the relative magnitude of juvenile salmonid losses to northern squawfish Ptychocheilus oregonensis in reservoirs throughout the Columbia River Basin. The second goal was to evaluate the northern squawfish control program and test critical assumptions about mid-reservoir predation processes. The final goal was to determine mechanisms underlying northern squawfish recruitment and factors affecting year-class strength

Incorporating movement patterns to improve survival estimates for juvenile bull trout

Science.gov (United States)

Bowerman, Tracy; Budy, Phaedra

2012-01-01

Populations of many fish species are sensitive to changes in vital rates during early life stages, but our understanding of the factors affecting growth, survival, and movement patterns is often extremely limited for juvenile fish. These critical information gaps are particularly evident for bull trout Salvelinus confluentus, a threatened Pacific Northwest char. We combined several active and passive mark–recapture and resight techniques to assess migration rates and estimate survival for juvenile bull trout (70–170 mm total length). We evaluated the relative performance of multiple survival estimation techniques by comparing results from a common Cormack–Jolly–Seber (CJS) model, the less widely used Barker model, and a simple return rate (an index of survival). Juvenile bull trout of all sizes emigrated from their natal habitat throughout the year, and thereafter migrated up to 50 km downstream. With the CJS model, high emigration rates led to an extreme underestimate of apparent survival, a combined estimate of site fidelity and survival. In contrast, the Barker model, which allows survival and emigration to be modeled as separate parameters, produced estimates of survival that were much less biased than the return rate. Estimates of age-class-specific annual survival from the Barker model based on all available data were 0.218±0.028 (estimate±SE) for age-1 bull trout and 0.231±0.065 for age-2 bull trout. This research demonstrates the importance of incorporating movement patterns into survival analyses, and we provide one of the first field-based estimates of juvenile bull trout annual survival in relatively pristine rearing conditions. These estimates can provide a baseline for comparison with future studies in more impacted systems and will help managers develop reliable stage-structured population models to evaluate future recovery strategies.

Some quantitative indicators of postovulatory aging and its effect on larval and juvenile development of Atlantic salmon (Salmo salar).

Science.gov (United States)

Mommens, Maren; Storset, Arne; Babiak, Igor

2015-07-01

Modern out-of-season egg production in Atlantic salmon (Salmo salar) increases the risk of postovulatory aging (POA) of oocytes. Postovulatory aging is known to influence oocyte quality in salmonids, but reliable tests for POA are lacking in Atlantic salmon egg production. To address this problem, we have collected oocytes from the same 20 Atlantic salmon females sequentially in approximately 1-week intervals, from the start of ovulation until 28 days postovulation (dpo), to determine the effect of natural retention of matured oocytes in body coelomic cavity on further performance of embryos and juveniles produced from those oocytes. Also, we investigated oocyte water hardening and several coelomic fluid parameters as potential quantitative indicators of POA. Oocyte quality decreased significantly from 22 dpo onward, as inferred from decrease in fertilization success and survival of embryos, alevins, and juveniles and increase in alevin and juvenile deformity rates. The occurrence of head deformities was significantly related to postovulatory age of oocytes. Coelomic fluid pH decreased significantly at 28 dpo and correlated positively with fertilization rates (r = 0.45), normal eyed embryo rates (r = 0.67), and alevin relative survival rates (r = 0.63) and negatively correlated with total alevin deformity rates (r = -0.59). Oocyte weight gain at 60 minutes decreased significantly at 28 dpo and correlated negatively with total alevin deformities and the occurrence of cranial nodules (r = -0.99). Generally, quality of ovulated oocytes remained stable for the first 2 weeks after ovulation. Later on, POA negatively influenced Atlantic salmon embryo, alevin, and juvenile performance. For the first time, we show a long-term effect of POA on salmonid juvenile performance. Standardized pH measurements of coelomic fluid could potentially improve embryo and juvenile production by identifying low-quality oocytes at an early stage during the production. Copyright © 2015

Factors Affecting the Survival of Upstream Migrant Adult Salmonids in the Columbia River Basin : Recovery Issues for Threatened and Endangered Snake River Salmon : Technical Report 9 of 11.

Energy Technology Data Exchange (ETDEWEB)

Dauble, Dennis D.; Mueller, Robert P.

1993-06-01

The Bonneville Power Administration (BPA) is developing conservation planning documentation to support the National Marine Fisheries Service`s (NMFS) recovery plan for Columbia Basin salmonid stocks that are currently listed under the Endangered Species Act (ESA). Information from the conservation planning documentation will be used as a partial scientific basis for identifying alternative conservation strategies and to make recommendations toward conserving, rebuilding, and ultimately removing these salmon stocks from the list of endangered species. This report describes the adult upstream survival study, a synthesis of biological analyses related to conditions affecting the survival of adult upstream migrant salmonids in the Columbia River system. The objective of the adult upstream survival study was to analyze existing data related to increasing the survival of adult migrant salmonids returning to the Snake River system. The fate and accountability of each stock during its upstream migration period and the uncertainties associated with measurements of escapement and survival were evaluated. Operational measures that affected the survival of adult salmon were evaluated including existing conditions, augmented flows from upstream storage release, and drawdown of mainstem reservoirs. The potential impacts and benefits of these measures to each ESA stock were, also described based on considerations of species behavior and run timing.

Passage and survival probabilities of juvenile Chinook salmon at Cougar Dam, Oregon, 2012

Science.gov (United States)

Beeman, John W.; Evans, Scott D.; Haner, Philip V.; Hansel, Hal C.; Hansen, Amy C.; Smith, Collin D.; Sprando, Jamie M.

2014-01-01

This report describes studies of juvenile-salmon dam passage and apparent survival at Cougar Dam, Oregon, during two operating conditions in 2012. Cougar Dam is a 158-meter tall rock-fill dam used primarily for flood control, and passes water through a temperature control tower to either a powerhouse penstock or to a regulating outlet (RO). The temperature control tower has moveable weir gates to enable water of different elevations and temperatures to be drawn through the dam to control water temperatures downstream. A series of studies of downstream dam passage of juvenile salmonids were begun after the National Oceanic and Atmospheric Administration determined that Cougar Dam was impacting the viability of anadromous fish stocks. The primary objectives of the studies described in this report were to estimate the route-specific fish passage probabilities at the dam and to estimate the survival probabilities of fish passing through the RO. The first set of dam operating conditions, studied in November, consisted of (1) a mean reservoir elevation of 1,589 feet, (2) water entering the temperature control tower through the weir gates, (3) most water routed through the turbines during the day and through the RO during the night, and (4) mean RO gate openings of 1.2 feet during the day and 3.2 feet during the night. The second set of dam operating conditions, studied in December, consisted of (1) a mean reservoir elevation of 1,507 ft, (2) water entering the temperature control tower through the RO bypass, (3) all water passing through the RO, and (4) mean RO gate openings of 7.3 feet during the day and 7.5 feet during the night. The studies were based on juvenile Chinook salmon (Oncorhynchus tshawytscha) surgically implanted with radio transmitters and passive integrated transponder (PIT) tags. Inferences about general dam passage percentage and timing of volitional migrants were based on surface-acclimated fish released in the reservoir. Dam passage and apparent

Impacts of Columbia River discharge on salmonid habitat: 2. Changes in shallow-water habitat

Science.gov (United States)

Kukulka, Tobias; Jay, David A.

2003-09-01

This is the second part of an investigation that analyzes human alteration of shallow-water habitat (SWH) available to juvenile salmonids in the tidal Lower Columbia River. Part 2 develops a one-dimensional, subtidal river stage model that explains ˜90% of the stage variance in the tidal river. This model and the tidal model developed in part 1 [, 2003] uncouple the nonlinear interaction of river tides and river stage by referring both to external forcing by river discharge, ocean tides, and atmospheric pressure. Applying the two models, daily high-water levels were predicted for a reach from rkm-50 to rkm-90 during 1974 to 1998, the period of contemporary management. Predicted water levels were related to the bathymetry and topography to determine the changes in shallow-water habitat area (SWHA) caused by flood control dikes and altered flow management. Model results suggest that diking and a >40% reduction of peak flows have reduced SWHA by ˜62% during the crucial spring freshet period during which juvenile salmon use of SWHA is maximal. Taken individually, diking and flow cycle alteration reduced spring freshet SWHA by 52% and 29%, respectively. SWHA has been both displaced to lower elevations and modified in its character because tidal range has increased. Our models of these processes are economical for the very long simulations (seasons to centuries) needed to understand historic changes and climate impacts on SWH. Through analysis of the nonlinear processes controlling surface elevation in a tidal river, we have identified some of the mechanisms that link freshwater discharge to SWH and salmonid survival.

Cultivation of sponge larvae: settlement, survival, and growth of juveniles

NARCIS (Netherlands)

Caralt, de S.; Otjens, H.; Uriz, M.J.; Wijffels, R.H.

2007-01-01

The aim of this study was to culture sponge juveniles from larvae. Starting from larvae we expected to enhance the survival and growth, and to decrease the variation in these parameters during the sponge cultures. First, settlement success, morphological changes during metamorphosis, and survival of

Survival of migrating sea trout (Salmo trutta ) smolts during their passage of an artificial lake in a Danish lowland stream

DEFF Research Database (Denmark)

Schwinn, Michael; Aarestrup, Kim; Baktoft, Henrik

2017-01-01

Artificial lake development is often used as a management tool to reduce nutrient runoff to coastal waters. Denmark has restored more than 10 000 ha of wetlands and lakes in the last 14 years as a consequence of ‘Action Plans for the Aquatic Environment’, which aim to meet the demands...... of the European Union’s Water Framework Directive. Juvenile, seaward migrating salmonids are highly affected by impounded waterbodies, as they are subjected to extraordinary high mortalities due to predation and altered habitat. From 2005 to 2015, survival and migration patterns of wild brown trout (Salmo trutta....... Water temperature and discharge were key environmental factors affecting survival of the smolts during the passage of the lake. Furthermore, smolt survival was negatively correlated with condition factor. This elevated level of smolt mortality may seriously compromise self-sustaining anadromous salmonid...

Performance Assessment of Suture Type in Juvenile Chinook Salmon Surgically Implanted with Acoustic Transmitters

Energy Technology Data Exchange (ETDEWEB)

Deters, Katherine A.; Brown, Richard S.; Carter, Kathleen M.; Boyd, James W.

2009-02-27

The objective of this study was to determine the best overall suture material to close incisions from the surgical implantation of Juvenile Salmon Acoustic Telemetry System (JSATS) acoustic microtransmitters in subyearling Chinook salmon Oncorhynchus tshawytscha. The effects of seven suture materials, four surgeons, and two water temperatures on suture retention, incision openness, tag retention, tissue inflammation, and tissue ulceration were quantified. The laboratory study, conducted by researchers at the Pacific Northwest National Laboratory, supports a larger effort under way for the U.S. Army Corps of Engineers, Portland District, aimed at determining the suitability of acoustic telemetry for estimating short- and longer-term (30-60 days) juvenile-salmonid survival at Columbia and Snake River dams and through the lower Columbia River.

Evaluation of juvenile salmonid behavior near a prototype weir box at Cowlitz Falls Dam, Washington, 2013

Science.gov (United States)

Kock, Tobias J.; Liedtke, Theresa L.; Ekstrom, Brian K.; Tomka, Ryan G.; Rondorf, Dennis W.

2014-01-01

Collection of juvenile salmonids at Cowlitz Falls Dam is a critical part of the effort to restore salmon in the upper Cowlitz River because the majority of fish that are not collected at the dam pass downstream and enter a large reservoir where they become landlocked and lost to the anadromous fish population. However, the juvenile fish collection system at Cowlitz Falls Dam has failed to achieve annual collection goals since it first began operating in 1996. Since that time, numerous modifications to the fish collection system have been made and several prototype collection structures have been developed and tested, but these efforts have not substantially increased juvenile fish collection. Studies have shown that juvenile steelhead (Oncorhynchus mykiss), coho salmon (Oncorhynchus kisutch), and Chinook salmon (Oncorhynchus tshawytscha) tend to locate the collection entrances effectively, but many of these fish are not collected and eventually pass the dam through turbines or spillways. Tacoma Power developed a prototype weir box in 2009 to increase capture rates of juvenile salmonids at the collection entrances, and this device proved to be successful at retaining those fish that entered the weir. However, because of safety concerns at the dam, the weir box could not be deployed near a spillway gate where the prototype was tested, so the device was altered and re-deployed at a different location, where it was evaluated during 2013. The U.S. Geological Survey conducted an evaluation using radiotelemetry to monitor fish behavior near the weir box and collection flumes. The evaluation was conducted during April–June 2013. Juvenile steelhead and coho salmon (45 per species) were tagged with a radio transmitter and passive integrated transponder (PIT) tag, and released upstream of the dam. All tagged fish moved downstream and entered the forebay of Cowlitz Falls Dam. Median travel times from the release site to the forebay were 0.8 d for steelhead and 1.2 d for coho

Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta, Lower Columbia River, 2007

Energy Technology Data Exchange (ETDEWEB)

Sobocinski, Kathryn L.; Johnson, Gary E.; Sather, Nichole K.; Storch, Adam; Jones, Tucker A.; Mallette, Christine; Dawley, Earl M.; Skalski, John R.; Teel, David; Moran, Paul

2008-03-18

This document is the first annual report for the study titled “Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta in the Lower Columbia River.” Hereafter, we refer to this research as the Tidal Freshwater Monitoring (TFM) Study. The study is part of the research, monitoring, and evaluation effort developed by the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS). The project is performed under the auspices of the Northwest Power and Conservation Council’s Columbia Basin Fish and Wildlife Program.

Survival of Juvenile Chinook Salmon Passing the Bonneville Dam Spillway in 2007

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Zimmerman, Shon A.; Durham, Robin E.; Fischer, Eric S.; Kim, Jina; Townsend, R. L.; Skalski, J. R.; Buchanan, Rebecca A.; McComas, Roy L.

2008-12-01

The U.S. Army Corps of Engineers Portland District (CENWP) funds numerous evaluations of fish passage and survival on the Columbia River. In 2007, the CENWP asked Pacific Northwest National Laboratory to conduct an acoustic telemetry study to estimate the survival of juvenile Chinook salmon passing the spillway at Bonneville Dam. This report documents the study results which are intended to be used to improve the conditions juvenile anadromous fish experience when passing through the dams that the Corps operates on the river.

Dispersal and survival of stocked juvenile hatchery-reared Atlantic sturgeon (Acipenser oxyrinchus

Directory of Open Access Journals (Sweden)

Kapusta Andrzej

2016-12-01

Full Text Available The post-stocking dispersal of juvenile Atlantic sturgeon (Acipenser oxyrinchus Mitchill in the Wis3oka River (southern Poland was investigated using biotelemetry. Thirty-five hatchery-reared juvenile A. oxyrinchus were tagged with radio or acoustic transmitters and tracked using mobile surveys and fixed receivers. Daily movement patterns were similar in 2009 and 2010. The sturgeon migrated with a mean speed of 1.42 km h-1 in 2009 and of 2.06 km h-1 in 2010. Migration rate was not regarded as being dependent on juvenile sturgeon size. The confirmed survival of individuals from the two field seasons differed slightly over the course of this study. Short-term survival of A. oxyrinchus was 86.7 and 90% in 2009 and 2010, respectively.

Developing a predation index and evaluating ways to reduce salmonid losses to predation in the Columbia River basin

International Nuclear Information System (INIS)

Nigro, A.A.

1990-12-01

We report our results of studies to develop a predation index and evaluate ways to reduce juvenile salmonid losses to predation in the Columbia River Basin. Study objectives of each were: develop an index to estimate predation losses of juvenile salmonids (Oncorhynchus spp) in reservoirs throughout the Columbia River Basin, describe the relationships among predator-caused mortality of juvenile salmonids and physical and biological variables, examine the feasibility of developing bounty, commercial or recreational fisheries on northern squawfish (Ptychocheilus oregonensis) and develop a plan to evaluate the efficacy of predator control fisheries; determine the economic feasibility of developing bounty and commercial fisheries for northern squawfish, assist ODFW with evaluating the economic feasibility of recreational fisheries for northern squawfish and assess the economic feasibility of utilizing northern squawfish, carp (Cyprinus carpio) and suckers (Castostomus spp) in multispecies fisheries; evaluate commercial technology of various fishing methods for harvesting northern squawfish in Columbia River reservoirs and field test the effectiveness of selected harvesting systems, holding facilities and transportation systems; and modify the existing Columbia River Ecosystem Model (CREM) to include processes necessary to evaluate effects of removing northern squawfish on their population size structure and abundance, document the ecological processes, mathematical equations and computer (FORTRAN) programming of the revised version of CREM and conduct systematic analyses of various predator removal scenarios, using revised CREM to generate the simulations. Individual reports are indexed separately

An Enriched Environment Promotes Shelter-Seeking Behaviour and Survival of Hatchery-Produced Juvenile European Lobster (Homarus gammarus)

Science.gov (United States)

Aspaas, Stian; Grefsrud, Ellen Sofie; Fernö, Anders; Jensen, Knut Helge; Trengereid, Henrik; Agnalt, Ann-Lisbeth

2016-01-01

The high loss of newly released hatchery-reared European lobster (Homarus gammarus) juveniles for stock enhancement is believed to be the result of maladaptive anti-predator behaviour connected to deprived stimuli in the hatchery environment. Our objective was to learn if an enriched hatchery environment enhances shelter-seeking behaviour and survival. In the “naïve” treatment, the juveniles were raised in single compartments without substrate and shelter whereas juveniles in the “exposed” treatment experienced substrate, shelter and interactions with conspecifics. Three experiments with increasing complexity were conducted. Few differences in shelter-seeking behaviour were found between treatments when one naïve or one exposed juvenile were observed alone. When observing interactions between one naïve and one exposed juvenile competing for shelter, naïve juveniles more often initiated the first aggressive encounter. The third experiment was set up to simulate a release for stock enhancement. Naïve and exposed juveniles were introduced to a semi-natural environment including substrate, a limited number of shelters and interactions with conspecifics. Shelter occupancy was recorded three times during a period of 35 days. Exposed juveniles occupied more shelters, grew larger and had higher survival compared with naïve juveniles. Our results demonstrate that experience of environmental complexity and social interactions increase shelter-seeking ability and survival in hatchery reared lobster juveniles. PMID:27560932

An Enriched Environment Promotes Shelter-Seeking Behaviour and Survival of Hatchery-Produced Juvenile European Lobster (Homarus gammarus).

Science.gov (United States)

Aspaas, Stian; Grefsrud, Ellen Sofie; Fernö, Anders; Jensen, Knut Helge; Trengereid, Henrik; Agnalt, Ann-Lisbeth

2016-01-01

The high loss of newly released hatchery-reared European lobster (Homarus gammarus) juveniles for stock enhancement is believed to be the result of maladaptive anti-predator behaviour connected to deprived stimuli in the hatchery environment. Our objective was to learn if an enriched hatchery environment enhances shelter-seeking behaviour and survival. In the "naïve" treatment, the juveniles were raised in single compartments without substrate and shelter whereas juveniles in the "exposed" treatment experienced substrate, shelter and interactions with conspecifics. Three experiments with increasing complexity were conducted. Few differences in shelter-seeking behaviour were found between treatments when one naïve or one exposed juvenile were observed alone. When observing interactions between one naïve and one exposed juvenile competing for shelter, naïve juveniles more often initiated the first aggressive encounter. The third experiment was set up to simulate a release for stock enhancement. Naïve and exposed juveniles were introduced to a semi-natural environment including substrate, a limited number of shelters and interactions with conspecifics. Shelter occupancy was recorded three times during a period of 35 days. Exposed juveniles occupied more shelters, grew larger and had higher survival compared with naïve juveniles. Our results demonstrate that experience of environmental complexity and social interactions increase shelter-seeking ability and survival in hatchery reared lobster juveniles.

Acoustic Imaging Evaluation of Juvenile Salmonid Behavior in the Immediate Forebay of the Water Temperature Control Tower at Cougar Dam, 2010

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Johnson, Gary E.; Royer, Ida M.; Phillips, Nathan RJ; Hughes, James S.; Fischer, Eric S.; Ham, Kenneth D.; Ploskey, Gene R.

2012-04-01

This report presents the results of an evaluation of juvenile Chinook salmon (Oncorhynchus tshawytscha) behavior at Cougar Dam on the south fork of the McKenzie River in Oregon in 2010. The study was conducted by the Pacific Northwest National Laboratory for the U.S. Army Corps of Engineers (USACE). The overall goal of the study was to characterize juvenile salmonid behavior and movement patterns in the immediate forebay of the Water Temperature Control (WTC) tower of the dam for USACE and fisheries resource managers use in making decisions about bioengineering designs for long-term structures and/or operations to facilitate safe downstream passage for juvenile salmonids. We collected acoustic imaging (Dual-Frequency Identification Sonar; DIDSON) data from March 1, 2010, through January 31, 2011. Juvenile salmonids (hereafter, called 'fish') were present in the immediate forebay of the WTC tower throughout the study. Fish abundance index was low in early spring (<200 fish per sample-day), increased in late April, and peaked on May 19 (6,039 fish). A second peak was observed on June 6 (2904 fish). Fish abundance index decreased in early June and remained low in the summer months (<100 fish per sample-day). During the fall and winter, fish numbers varied with a peak on November 10 (1881 fish) and a minimum on December 7 (12 fish). A second, smaller, peak occurred on December 22 (607 fish). A univariate statistical analysis indicated fish abundance index (log10-transformed) was significantly (P<0.05) positively correlated with forebay elevation, velocity over the WTC tower intake gate weirs, and river flows into the reservoir. A subsequent multiple regression analysis resulted in a model (R2=0.70) predicting fish abundance (log-transformed index values) using two independent variables of mean forebay elevation and the log10 of the forebay elevation range. From the approximate fish length measurements made using the DIDSON imaging software, the average fish

Hydroacoustic Evaluation of Juvenile Salmonid Passage at The Dalles Dam Spillway, 2006

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Khan, Fenton; Skalski, John R.; Rakowski, Cynthia L.; Richmond, Marshall C.; Serkowski, John A.

2007-05-24

The objective of this study was to determine detailed vertical, horizontal, intensive, and diel distributions of juvenile salmonid passage at the spillway at The Dalles Dam from April 12 to July16, 2006. These data are being applied in the Spillway Improvements Program to position release pipes for direct injury and mortality studies and to provide baseline data for assessment of the vortex suppression devices scheduled for deployment in 2007. We estimated fish distributions from hydroacoustic data collected with split-beam transducers arrayed across Bays 1 through 9 and 14. Spill at ~20 kcfs per bay was bulked at Bays 1-6, although the other bays were opened at times during the study to maintain a 40% spill percentage out of total project discharge. The vertical distribution of fish was skewed toward the surface during spring, but during summer, passage peaked at 2-3 m above the spillway ogee. Fish passage rates (number per hour) and fish densities (number per kcfs) were highest at Bay 6, followed by passage at Bay 5. This result comports with spillway horizontal distribution data from radio telemetry and hydroacoustic studies in 2004. The vertical and horizontal distribution of fish passage at bays 5 and 6 was much more variable during spring than summer and more variable at bay 5 than bay 6. Diel distribution data revealed that fish passage was highest during 0600-0700 h in spring; otherwise passage was reasonably uniform on a diel basis. This study substantiates the purpose of the spillway vortex suppression device to re-distribute downstream migrants away from Bay 6 toward Bays 1-5.

Hydroacoustic Evaluation of Juvenile Salmonid Passage and Distribution at Detroit Dam, 2011

Energy Technology Data Exchange (ETDEWEB)

Khan, Fenton; Royer, Ida M.; Johnson, Gary E.; Ham, Kenneth D.

2012-11-15

Pacific Northwest National Laboratory evaluated juvenile salmonid passage and distribution at Detroit Dam (DET) on the North Santiam River, Oregon for the U.S. Army Corps of Engineers (USACE) to provide data to support decisions on long-term measures to enhance downstream passage at DET and others dams in USACE’s Willamette Valley Project. This study was conducted in response to regulatory requirements necessitated by the listing of Upper Willamette River Spring Chinook salmon (Oncorhynchus tshawytscha) and Upper Willamette River steelhead (O. mykiss) as threatened under the Endangered Species Act. The goal of the study was to provide information of juvenile salmonid passage and distribution at DET from February 2011 through February 2012. The results of the hydroacoustic study provide new and, in some cases, first-ever data on passage estimates, run timing, distributions, and relationships between fish passage and environmental variables at the dam. This information will inform management decisions on the design and development of surface passage and collection devices to help restore Chinook salmon populations in the North Santiam River watershed above DET. During the entire study period, an estimated total of 182,526 smolt-size fish (±4,660 fish, 95% CI) passed through turbine penstock intakes. Run timing peaked in winter and early spring months. Passage rates were highest during late fall, winter and early spring months and low during summer. Horizontal distribution for hours when both turbine units were operated simultaneously indicated Unit 2 passed almost twice as much fish as Unit 1. Diel distribution for smolt-size fish during the study period was fairly uniform, indicating fish were passing the turbines at all times of the day. A total of 5,083 smolt-size fish (± 312 fish, 95% CI) were estimated passed via the spillway when it was open between June 23 and September 27, 2011. Daily passage was low at the spillway during the June-August period, and

Assessment of Salmonids and Their Habitat Conditions in the Walla Walla River Basin within Washington, Annual Report 2002-2003.

Energy Technology Data Exchange (ETDEWEB)

Mendel, Glen; Trump, Jeremy; Gembala, Mike

2003-09-01

This study began in 1998 to assess salmonid distribution, relative abundance, genetics, and the condition of salmonid habitats in the Walla Walla River basin. Stream flows in the Walla Walla Basin continue to show a general trend that begins with a sharp decline in discharge in late June, followed by low summer flows and then an increase in discharge in fall and winter. Manual stream flow measurements at Pepper bridge showed an increase in 2002 of 110-185% from July-September, over flows from 2001. This increase is apparently associated with a 2000 settlement agreement between the U.S. Fish and Wildlife Service (USFWS) and the irrigation districts to leave minimum flows in the river. Stream temperatures in the Walla Walla basin were similar to those in 2001. Upper montane tributaries maintained maximum summer temperatures below 65 F, while sites in mid and lower Touchet and Walla Walla rivers frequently had daily maximum temperatures well above 68 F (high enough to inhibit migration in adult and juvenile salmonids, and to sharply reduce survival of their embryos and fry). These high temperatures are possibly the most critical physiological barrier to salmonids in the Walla Walla basin, but other factors (available water, turbidity or sediment deposition, cover, lack of pools, etc.) also play a part in salmonid survival, migration, and breeding success. The increased flows in the Walla Walla, due to the 2000 settlement agreement, have not shown consistent improvements to stream temperatures. Rainbow/steelhead (Oncorhynchus mykiss) trout represent the most common salmonid in the basin. Densities of Rainbow/steelhead in the Walla Walla River from the Washington/Oregon stateline to Mojonnier Rd. dropped slightly from 2001, but are still considerably higher than before the 2000 settlement agreement. Other salmonids including; bull trout (Salvelinus confluentus), chinook salmon (Oncorhynchus tshawytscha), mountain whitefish (Prosopium williamsoni), and brown trout (Salmo

Vaccination of free-living juvenile wild rabbits (Oryctolagus cuniculus) against myxomatosis improved their survival.

Science.gov (United States)

Guitton, Jean-Sébastien; Devillard, Sébastien; Guénézan, Michel; Fouchet, David; Pontier, Dominique; Marchandeau, Stéphane

2008-04-17

For several decades, the populations of the European wild rabbit (Oryctolagus cuniculus) have declined, which is partly due to myxomatosis. Vaccination against this disease is expected to contribute to restoration of rabbit populations but the actual impact of myxomatosis is not well known and vaccination might have some negative effects. We analyzed the capture-mark-recapture data obtained in a 4-year field experiment (1991-1994) in a park near Paris, France wherein 300 out of 565 seronegative juvenile rabbits were vaccinated at first capture against myxomatosis with the nontransmissible Dervaximyxo SG33 vaccine. After accounting for weight at first capture, age-class (juvenile/adult), "trap-happiness" and season (spring/autumn) of the capture event, vaccinated rabbits had 1.8-fold greater odds of surviving than the unvaccinated rabbits. The average summer survival risk for vaccinated juveniles was 0.63 (+/-0.08 S.E.) whereas it was 0.48 (+/-0.08 S.E.) for unvaccinated juvenile rabbits.

The energetic consequences of habitat structure for forest stream salmonids.

Science.gov (United States)

Naman, Sean M; Rosenfeld, Jordan S; Kiffney, Peter M; Richardson, John S

2018-05-08

1.Increasing habitat availability (i.e. habitat suitable for occupancy) is often assumed to elevate the abundance or production of mobile consumers; however, this relationship is often nonlinear (threshold or unimodal). Identifying the mechanisms underlying these nonlinearities is essential for predicting the ecological impacts of habitat change, yet the functional forms and ultimate causation of consumer-habitat relationships are often poorly understood. 2.Nonlinear effects of habitat on animal abundance may manifest through physical constraints on foraging that restrict consumers from accessing their resources. Subsequent spatial incongruence between consumers and resources should lead to unimodal or saturating effects of habitat availability on consumer production if increasing the area of habitat suitable for consumer occupancy comes at the expense of habitats that generate resources. However, the shape of this relationship could be sensitive to cross-ecosystem prey subsidies, which may be unrelated to recipient habitat structure and result in more linear habitat effects on consumer production. 3.We investigated habitat-productivity relationships for juveniles of stream-rearing Pacific salmon and trout (Oncorhynchus spp.), which typically forage in low-velocity pool habitats, while their prey (drifting benthic invertebrates) are produced upstream in high-velocity riffles. However, juvenile salmonids also consume subsidies of terrestrial invertebrates that may be independent of pool-riffle structure. 4.We measured salmonid biomass production in 13 experimental enclosures each containing a downstream pool and upstream riffle, spanning a gradient of relative pool area (14-80% pool). Increasing pool relative to riffle habitat area decreased prey abundance, leading to a nonlinear saturating effect on fish production. We then used bioenergetics model simulations to examine how the relationship between pool area and salmonid biomass is affected by varying levels of

Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta, Lower Columbia River, 2007 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Sobocinski, Kathryn; Johnson, Gary; Sather, Nichole [Pacific Northwest National Laboratory

2008-03-17

This document is the first annual report for the study titled 'Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta in the Lower Columbia River'. Hereafter, we refer to this research as the Tidal Freshwater Monitoring (TFM) Study. The study is part of the research, monitoring, and evaluation effort developed by the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS). The project is performed under the auspices of the Northwest Power and Conservation Council's Columbia Basin Fish and Wildlife Program. The goal of the 2007-2009 Tidal Freshwater Monitoring Study is to answer the following questions: In what types of habitats within the tidal freshwater area of the lower Columbia River and estuary (LCRE; Figure 1) are yearling and subyearling salmonids found, when are they present, and under what environmental conditions?1 And, what is the ecological importance2 of shallow (0-5 m) tidal freshwater habitats to the recovery of Upper Columbia River spring Chinook salmon and steelhead and Snake River fall Chinook salmon? Research in 2007 focused mainly on the first question, with fish stock identification data providing some indication of Chinook salmon presence at the variety of habitat types sampled. The objectives and sub-objectives for the 2007 study were as follows: (1) Habitat and Fish Community Characteristics-Provide basic data on habitat and fish community characteristics for yearling and subyearling salmonids at selected sites in the tidal freshwater reach in the vicinity of the Sandy River delta. (1a) Characterize vegetation assemblage percent cover, conventional water quality, substrate composition, and beach slope at each of six sampling sites in various tidal freshwater habitat types. (1b

Diel resource partitioning among juvenile Atlantic Salmon, Brown Trout, and Rainbow Trout during summer

Science.gov (United States)

Johnson, James H.; McKenna, James E.

2015-01-01

Interspecific partitioning of food and habitat resources has been widely studied in stream salmonids. Most studies have examined resource partitioning between two native species or between a native species and one that has been introduced. In this study we examine the diel feeding ecology and habitat use of three species of juvenile salmonids (i.e., Atlantic Salmon Salmo salar, Brown Trout Salmo trutta, and Rainbow Trout Oncorhynchus mykiss) in a tributary of Skaneateles Lake, New York. Subyearling Brown Trout and Rainbow Trout fed more heavily from the drift than the benthos, whereas subyearling Atlantic Salmon fed more from the benthos than either species of trout. Feeding activity of Atlantic Salmon and Rainbow Trout was similar, with both species increasing feeding at dusk, whereas Brown Trout had no discernable feeding peak or trough. Habitat availability was important in determining site-specific habitat use by juvenile salmonids. Habitat selection was greater during the day than at night. The intrastream, diel, intraspecific, and interspecific variation we observed in salmonid habitat use in Grout Brook illustrates the difficulty of acquiring habitat use information for widespread management applications.

Relative survival of juvenile chinook salmon (Oncorhynchus tshawyischa) through a Bonneville dam on the Columbia River

International Nuclear Information System (INIS)

Ferguson, J.

1993-01-01

The Bonneville Dam second powerhouse bypass system for juvenile salmon has one 6.1-m submersible travelling screen in each intake of all eight turbines, for a total of 24 screens. These screens set up a hydraulic cushion that deflects juvenile salmon away from the turbine intakes and into vertical bulkhead slots, from which they exit by their own volition into a collection gallery that travels the length of the powerhouse to a dewatering station and the outlet. A multiple-year evaluation was conducted on the comparative survival of subyearling chinook salmon through various passage modes at the dam. Using this information, operational scenarios could then be formulated to provide additional juvenile protection while meeting power system demands. In the summer, the juvenile salmon that passed through the bypass system had significantly lower survival rates than upper and lower turbine, spillway, and downstream control groups. Predation by northern squawfish (Ptychocheilus oregonensis) was suspected to have been the cause of high mortalities among bypassed fish. No significant differences existed between survival rates of upper and lower turbine groups. 7 refs., 2 figs., 1 tab

A Markov chain analysis of the movements of juvenile salmonids, including sockeye salmon, in the forebay of McNary Dam, Washington and Oregon, 2006-09

Science.gov (United States)

Adams, Noah S.; Hatton, Tyson W.

2012-01-01

Passage and survival data were collected at McNary Dam between 2006 and 2009. These data have provided critical information for resource managers to implement structural and operational changes designed to improve the survival of juvenile salmonids as they migrate past the dam. Much of the valuable information collected at McNary Dam was in the form of three-dimensional (hereafter referred to as 3-D) tracks of fish movements in the forebay. These data depicted the behavior of multiple species (in three dimensions) during different diel periods, spill conditions, powerhouse operations, and testing of the surface bypass structures (temporary spillway weirs; TSWs). One of the challenges in reporting 3-D results is presenting the information in a manner that allows interested parties to summarize the behavior of many fish over many different conditions across multiple years. To accomplish this, we used a Markov chain analysis to characterize fish movement patterns in the forebay of McNary Dam. The Markov chain analysis allowed us to numerically summarize the behavior of fish in the forebay. This report is the second report published in 2012 that uses this analytical method. The first report included only fish released as part of the annual studies conducted at McNary Dam. This second report includes sockeye salmon that were released as part of studies conducted by the Chelan and Grant County Public Utility Districts at mid-Columbia River dams. The studies conducted in the mid-Columbia used the same transmitters as were used for McNary Dam studies, but transmitter pulse width was different between studies. Additionally, no passive integrated transponder tags were implanted in sockeye salmon. Differences in transmitter pulse width resulted in lower detection probabilities for sockeye salmon at McNary Dam. The absence of passive integrated transponder tags prevented us from determining if fish passed the powerhouse through the juvenile bypass system (JBS) or turbines. To

Water Temperature, Invertebrate Drift, and the Scope for Growth for Juvenile Spring Chinook Salmon.

Science.gov (United States)

Lovtang, J. C.; Li, H. W.

2005-05-01

We present a bioenergetic assessment of habitat quality based on the concept of the scope for growth for juvenile Chinook salmon. Growth of juvenile salmonids during the freshwater phase of their life history depends on a balance between two main factors: energy intake and metabolic costs. The metabolic demands of temperature and the availability of food play integral roles in determining the scope for growth of juvenile salmonids in stream systems. We investigated differences in size of juvenile spring Chinook salmon in relation to water temperature and invertebrate drift density in six unique study reaches in the Metolius River Basin, a tributary of the Deschutes River in Central Oregon. This project was initiated to determine the relative quality and potential productivity of habitat in the Metolius Basin prior to the reintroduction of spring Chinook salmon, which were extirpated from the middle Deschutes basin in the early 1970's due to the construction of a hydroelectric dam. Variations in the growth of juvenile Chinook salmon can be described using a multiple regression model of water temperature and invertebrate drift density. We also discuss the relationships between our bioenergetic model, variations of the ideal free distribution model, and physiological growth models.

Research, Monitoring, and Evaluation of Avian Predation on Salmonid Smolts in the Lower and Mid-Columbia River, 2008 Draft Season Summary.

Energy Technology Data Exchange (ETDEWEB)

Roby, Daniel D. [USGS - Oregon Cooperative Fish and Wildlife Research Unit, Department of Fisheries and Wildlife, Oregon State University; Collis, Ken [Real Time Research, Inc.; Lyons, Donald E. [USGS - Oregon Cooperative Fish and Wildlife Research Unit, Oregon State University

2009-07-08

This report describes investigations into predation by piscivorous colonial waterbirds on juvenile salmonids (Oncorhynchus spp.) from throughout the Columbia River basin during 2008. East Sand Island in the Columbia River estuary again supported the largest known breeding colony of Caspian terns (Hydroprogne caspia) in the world (approximately 10,700 breeding pairs) and the largest breeding colony of double-crested cormorants (Phalacrocorax auritus) in western North America (approximately 10,950 breeding pairs). The Caspian tern colony increased from 2007, but not significantly so, while the double-crested cormorant colony experienced a significant decline (20%) from 2007. Average cormorant nesting success in 2008, however, was down only slightly from 2007, suggesting that food supply during the 2008 nesting season was not the principal cause of the decline in cormorant colony size. Total consumption of juvenile salmonids by East Sand Island Caspian terns in 2008 was approximately 6.7 million smolts (95% c.i. = 5.8-7.5 million). Caspian terns nesting on East Sand Island continued to rely primarily on marine forage fishes as a food supply. Based on smolt PIT tag recoveries on the East Sand Island Caspian tern colony, predation rates were highest on steelhead in 2008; minimum predation rates on steelhead smolts detected passing Bonneville Dam averaged 8.3% for wild smolts and 10.7% for hatchery-raised smolts. In 2007, total smolt consumption by East Sand Island double-crested cormorants was about 9.2 million juvenile salmonids (95% c.i. = 4.4-14.0 million), similar to or greater than that of East Sand Island Caspian terns during that year (5.5 million juvenile salmonids; 95% c.i. = 4.8-6.2 million). The numbers of smolt PIT tags recovered on the cormorant colony in 2008 were roughly proportional to the relative availability of PIT-tagged salmonids released in the Basin, suggesting that cormorant predation on salmonid smolts in the estuary was less selective than tern

Performance Assessment of Bi-Directional Knotless Tissue-Closure Devices in Juvenile Chinook Salmon Surgically Implanted with Acoustic Transmitters, 2009 - Final Report

Energy Technology Data Exchange (ETDEWEB)

Woodley, Christa M.; Wagner, Katie A.; Bryson, Amanda J.

2012-11-09

The purpose of this report is to assess the performance of bi-directional knotless tissue-closure devices for use in tagging juvenile salmon. This study is part of an ongoing effort at Pacific Northwest National Laboratory (PNNL) to reduce unwanted effects of tags and tagging procedures on the survival and behavior of juvenile salmonids, by assessing and refining suturing techniques, suture materials, and tag burdens. The objective of this study was to compare the performance of the knotless (barbed) suture, using three different suture patterns (treatments: 6-point, Wide “N”, Wide “N” Knot), to the current method of suturing (MonocrylTM monofilament, discontinuous sutures with a 2×2×2×2 knot) used in monitoring and research programs with a novel antiseptic barrier on the wound (“Second Skin”).

Predation by northern squawfish on live and dead juvenile chinook salmon

International Nuclear Information System (INIS)

Gadomski, D.M.; Hall-Griswold, J.A.

1992-01-01

Northern squawfish Ptychocheilus oregonensis is a major predator of juvenile salmonids Oncorhynchus spp. migrating downstream through the Columbia River. High predation rates occur just below dams. If northern squawfish selectively consume salmonids killed or injured during dam passage, previous estimates of predation mortality may be too high. We conducted laboratory experiments that indicate northern squawfish prefer dead juvenile chinook salmon O. tshawytscha over live individuals. When equal numbers of dead and live chinook salmon were offered to northern squawfish maintained on a natural photoperiod (15 h light: 9 h darkness), significantly more (P < 0.05) dead than live fish were consumed, both in 1,400-L circular tanks and in an 11,300-L raceway (62% and 79% of prey consumed were dead, respectively). When dead and live juvenile chinook salmon were provided in proportions more similar to those below dams (20% dead, 80% live), northern squawfish still selected for dead prey (36% of fish consumed were dead). In additional experiments, northern squawfish were offered a proportion of 20% dead juvenile chinook salmon during 4-h periods of either light or darkness. The predators were much more selective for dead chinook salmon during bright light (88% of fish consumed were dead) than during darkness (31% were dead)

Survival estimates - Survival estimates for the passage of juvenile salmonids through Snake and Columbia River dams and reservoirs

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This BPA-funded study provides estimates of smolt survival and travel time through individual reaches and reaches combined in the Snake and Columbia Rivers...

Survival and Passage of Yearling and Subyearling Chinook Salmon and Juvenile Steelhead at McNary Dam, 2012

Energy Technology Data Exchange (ETDEWEB)

Hughes, James S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weiland, Mark A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Woodley, Christa M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ploskey, Gene R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carpenter, Scott M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hennen, Matthew J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fischer, Eric S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Batton, George [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Carlson, Thomas J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cushing, Aaron W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Deng, Zhiqun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Etherington, D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fu, Tao [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Greiner, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ingraham, John M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Jin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Li, Xi [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Martinez, Jayson J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mitchell, T. D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rayamajhi, Bishes [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Seaburg, Adam [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skalski, J. R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Townsend, Richard L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wagner, Katie A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zimmerman, Shon A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2013-12-23

The study was designed to evaluate the passage and survival of yearling and subyearling Chinook salmon and juvenile steelhead at McNary Dam as stipulated by the 2008 Biological Opinion and Fish Accords and to assess performance measures including route-specific fish passage proportions, travel times, and survival based upon a virtual/paired-release model. This study supports the USACE’s continual effort to improve conditions for juvenile anadromous fish passing through Columbia River dams.

Modeling potential river management conflicts between frogs and salmonids

Science.gov (United States)

Steven F. Railsback; Bret C. Harvey; Sarah J. Kupferberg; Margaret M. Lang; Scott McBain; Hart H. Welsh

2016-01-01

Management of regulated rivers for yellow-legged frogs (Rana boylii) and salmonids exemplifies potential conflicts among species adapted to different parts of the natural flow and temperature regimes. Yellow-legged frogs oviposit in rivers in spring and depend on declining flows and warming temperatures for egg and tadpole survival and growth,...

Survival and causes of mortality in juvenile Puerto Rican parrots

Science.gov (United States)

G.D. Lindsey; W.J. Arendt; J. Kalina

1994-01-01

Fifteen juvenile Puerto Rican Parrots (Amazona vittata) from wild nests in 1985, 1986 and 1987 were radio monitored an average of 110 +_ 15.9 (SE) d (range 4-209 d) post-fiedging.. Minimum survival was 67% (n = 3) in 1985, 100%( n = 4) in 1986 and 43% (n = 7) in 1987. Most mortality (three of five deaths) occurred during the first 35 d following fledging. A major...

Anadromous salmonids in the Delta: New science 2006–2016

Science.gov (United States)

Perry, Russell W.; Buchanan, Rebecca A.; Brandes, Patricia L.; Burau, Jon R.; Israel, Joshua A

2016-01-01

As juvenile salmon enter the Sacramento–SanJoaquin River Delta (“the Delta”) they disperse among its complex channel network where they are subject to channel-specific processes that affect their rate of migration, vulnerability to predation, feeding success, growth rates, and ultimately, survival. In the decades before 2006, tools available to quantify growth, dispersal, and survival of juvenile salmon in this complex channel network were limited.Fortunately, thanks to technological advances such as acoustic telemetry and chemical and structural otolith analysis, much has been learned over the past decade about the role of the Delta in the life cycle of juvenile salmon. Here, we review new science between 2006and 2016 that sheds light on how different life stages and runs of juvenile salmon grow, move, and survive in the complex channel network of the Delta. One of the most important advances during the past decade has been the widespread adoption of acoustic telemetry techniques. Use of telemetry has shed light on how survival varies among alternative migration routes and the proportion of fish that use each migration route. Chemical and structural analysis of otoliths has provided insights about when juveniles left their natal river and provided evidence of extended rearing in the brackish or saltwater regions of the Delta. New advancements in genetics now allow individuals captured by trawls to be assigned to specific runs. Detailed information about movement and survival in the Delta has spurred development of agent-based models of juvenile salmon that are coupled to hydrodynamic models. Although much has been learned, knowledge gaps remain about how very small juvenile salmon (fry and parr) use the Delta. Understanding how all life stages of juvenile salmon grow, rear, and survive in the Delta is critical for devising management strategies that support a diversity of life history strategies.

An Ecosystem-Based Approach to Habitat Restoration Projects with Emphasis on Salmonids in the Columbia River Estuary, 2003 Technical Report.

Energy Technology Data Exchange (ETDEWEB)

Johnson, G.; Thom, R.; Whiting, A. (Pacific Northwest National Laboratory)

2003-11-01

-listed salmon populations and native species using the CRE. The program's underlying principles are: (1) projects are founded on the best available ecological restoration science, implemented in an ecosystem context, and developed with the intent to restore relevant ecological processes; (2) projects incorporate adaptive management practices with testable hypotheses to track ecological responses to a given restoration effort; and (3) projects are implemented in a coordinated, open process and scientific results from monitoring and evaluation are communicated widely and readily accessible. With this goal and these principles in mind, we developed an approach for CRE habitat restoration. The intent of this document is to provide a scientific basis and implementation guidelines for a habitat restoration program designed to improve ecosystem functions and enhance juvenile salmonid survival in the CRE. The stepwise approach to CRE habitat restoration outlined is somewhat general and broad because the available scientific information is incomplete, e.g., juvenile salmon usage of various CRE wetland habitats. As new data become available, a more specific, detailed plan than was possible here can be produced as an outgrowth of this document. In conclusion, this document provides a scientific basis and implementation guidelines for a habitat restoration program designed to improve ecosystem functions and enhance juvenile salmonid survival in the CRE. As more experience is gained with CRE habitat restoration and scientific uncertainties are resolved, this document should be used as a basis for a detailed habitat restoration plan that specifically addresses (1) which habitat types offer the greatest ecological benefit to salmon, (2) the location of potential sites that if restored would likely provide these habitat types, and (3) how and when the restoration work should be done. This document supports the use of adaptive management so that all elements of salmonid habitat restoration

Acoustic Telemetry Evaluation of Juvenile Salmonid Passage and Survival Proportions at John Day Dam, 2009

Energy Technology Data Exchange (ETDEWEB)

Weiland, Mark A.; Ploskey, Gene R.; Hughes, James S.; Deng, Zhiqun; Fu, Tao; Kim, Jin A.; Johnson, Gary E.; Fischer, Eric S.; Khan, Fenton; Zimmerman, Shon A.; Faber, Derrek M.; Carter, Kathleen M.; Boyd, James W.; Townsend, Richard L.; Skalski, J. R.; Monter, Tyrell J.; Cushing, Aaron W.; Wilberding, Matthew C.; Meyer, Matthew M.

2011-09-28

The overall purpose of the acoustic telemetry study at JDA during 2009 was to determine the best configuration and operation for JDA prior to conducting BiOp performance standard tests. The primary objective was to determine the best operation between 30% and 40% spill treatments. Route-specific and JDA to TDA forebay survival estimates, passage distribution, and timing/behavior metrics were used for comparison of 30% to a 40% spill treatments. A secondary objective was to evaluate the performance of TSWs installed in spill bays 15 and 16 and to estimate fish survival rates and passage efficiencies under 30% and 40% spill-discharge treatments each season.

Maximum Neutral Buoyancy Depth of Juvenile Chinook Salmon: Implications for Survival during Hydroturbine Passage

Energy Technology Data Exchange (ETDEWEB)

Pflugrath, Brett D.; Brown, Richard S.; Carlson, Thomas J.

2012-03-01

This study investigated the maximum depth at which juvenile Chinook salmon Oncorhynchus tshawytscha can acclimate by attaining neutral buoyancy. Depth of neutral buoyancy is dependent upon the volume of gas within the swim bladder, which greatly influences the occurrence of injuries to fish passing through hydroturbines. We used two methods to obtain maximum swim bladder volumes that were transformed into depth estimations - the increased excess mass test (IEMT) and the swim bladder rupture test (SBRT). In the IEMT, weights were surgically added to the fishes exterior, requiring the fish to increase swim bladder volume in order to remain neutrally buoyant. SBRT entailed removing and artificially increasing swim bladder volume through decompression. From these tests, we estimate the maximum acclimation depth for juvenile Chinook salmon is a median of 6.7m (range = 4.6-11.6 m). These findings have important implications to survival estimates, studies using tags, hydropower operations, and survival of juvenile salmon that pass through large Kaplan turbines typical of those found within the Columbia and Snake River hydropower system.

Spatial and temporal heterogeneity of infectious hematopoietic necrosis virus in Pacific Northwest salmonids

Science.gov (United States)

Breyta, Rachel; Black, Allison; Kaufman, John; Kurath, Gael

2016-01-01

The aquatic rhaboviral pathogen infectious hematopoietic necrosis virus (IHNV) causes acute disease in juvenile fish of a number of populations of Pacific salmonid species. Heavily managed in both marine and freshwater environments, these fish species are cultured during the juvenile stage in freshwater conservation hatcheries, where IHNV is one of the top three infectious diseases that cause serious morbidity and mortality. Therefore, a comprehensive study of viral genetic surveillance data representing 2590 field isolates collected between 1958 and 2014 was conducted to determine the spatial and temporal patterns of IHNV in the Pacific Northwest of the contiguous United States. Prevalence of infection varied over time, fluctuating over a rough 5–7 year cycle. The genetic analysis revealed numerous subgroups of IHNV, each of which exhibited spatial heterogeneity. Within all subgroups, dominant genetic types were apparent, though the temporal patterns of emergence of these types varied among subgroups. Finally, the affinity or fidelity of subgroups to specific host species also varied, where UC subgroup viruses exhibited a more generalist profile and all other subgroups exhibited a specialist profile. These complex patterns are likely synergistically driven by numerous ecological, pathobiological, and anthropogenic factors. Since only a few anthropogenic factors are candidates for managed intervention aimed at improving the health of threatened or endangered salmonid fish populations, determining the relative impact of these factors is a high priority for future studies.

Effects of Delayed Metamorphosis on Larval Survival, Metamorphosis, and Juvenile Performance of Four Closely Related Species of Tropical Sea Urchins (Genus Echinometra

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M. Aminur Rahman

2014-01-01

Full Text Available We report here, the effects of extended competency on larval survival, metamorphosis, and postlarval juvenile growth of four closely related species of tropical sea urchins, Echinometra sp. A (Ea, E. mathaei (Em, Echinometra sp. C (Ec, and E. oblonga (Eo. Planktotrophic larvae of all four species fed on cultured phytoplankton (Chaetoceros gracilis attained metamorphic competence within 22–24 days after fertilization. Competent larvae were forced to delay metamorphosis for up to 5 months by preventing them from settling in culture bottles with continuous stirring on a set of 10 rpm rotating rollers and larval survival per monthly intervals was recorded. Larval survival was highest at 24 days, when competence was attained (0 delayed period, and there were no significant differences among the four species. Larvae that had experienced a prolonged delay had reduced survival rate, metamorphosis success, and juvenile survival, but among older larvae, Em had the highest success followed by Ea, Eo, and Ec. Juveniles from larvae of all four species that metamorphosed soon after becoming competent tended to have higher growth rates (test diameter and length of spines than juveniles from larvae that metamorphosed after a prolonged period of competence with progressively slower growth the longer the prolonged period. Despite the adverse effects of delaying metamorphosis on growth parameters, competent larvae of all four species were able to survive up to 5 months and after metamorphosis grew into 1-month-old juveniles in lab condition. Overall, delayed larvae of Em showed significantly higher larval survival, metamorphosis, and juvenile survival than Ea and Eo, while Ec showed the lowest values in these performances. Em has the most widespread distribution of these species ranging from Africa to Hawaii, while Ec probably has the most restricted distribution. Consequently, differences in distribution may be related to differences in the ability to delay

Effects of delayed metamorphosis on larval survival, metamorphosis, and juvenile performance of four closely related species of tropical sea urchins (genus Echinometra).

Science.gov (United States)

Rahman, M Aminur; Yusoff, Fatimah Md; Arshad, A; Uehara, Tsuyoshi

2014-01-01

We report here, the effects of extended competency on larval survival, metamorphosis, and postlarval juvenile growth of four closely related species of tropical sea urchins, Echinometra sp. A (Ea), E. mathaei (Em), Echinometra sp. C (Ec), and E. oblonga (Eo). Planktotrophic larvae of all four species fed on cultured phytoplankton (Chaetoceros gracilis) attained metamorphic competence within 22-24 days after fertilization. Competent larvae were forced to delay metamorphosis for up to 5 months by preventing them from settling in culture bottles with continuous stirring on a set of 10 rpm rotating rollers and larval survival per monthly intervals was recorded. Larval survival was highest at 24 days, when competence was attained (0 delayed period), and there were no significant differences among the four species. Larvae that had experienced a prolonged delay had reduced survival rate, metamorphosis success, and juvenile survival, but among older larvae, Em had the highest success followed by Ea, Eo, and Ec. Juveniles from larvae of all four species that metamorphosed soon after becoming competent tended to have higher growth rates (test diameter and length of spines) than juveniles from larvae that metamorphosed after a prolonged period of competence with progressively slower growth the longer the prolonged period. Despite the adverse effects of delaying metamorphosis on growth parameters, competent larvae of all four species were able to survive up to 5 months and after metamorphosis grew into 1-month-old juveniles in lab condition. Overall, delayed larvae of Em showed significantly higher larval survival, metamorphosis, and juvenile survival than Ea and Eo, while Ec showed the lowest values in these performances. Em has the most widespread distribution of these species ranging from Africa to Hawaii, while Ec probably has the most restricted distribution. Consequently, differences in distribution may be related to differences in the ability to delay metamorphosis.

Development of an Index to Bird Predation of Juvenile Salmonids within the Yakima River, 2001 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Major, III, Walter; Grue, Christian E.; Ryding, Kristen E. (University of Washington, School of Aquatic and Fishery Sciences, Seattle, WA)

2002-08-01

Avian predation of fish is suspected to contribute to the loss of out-migrating juvenile salmonids in the Yakima Basin, potentially constraining natural and artificial production. In 1997 and 1998, the Yakima/ Klickitat Fisheries Project (YKFP)--whose goal is increasing natural production within the Yakima River--initiated investigations to assess the feasibility of developing an index to avian predation of juvenile salmon within the river. This research confirmed that Ring-billed Gulls and Common Mergansers were the primary avian predators of juvenile salmon (Phinney et al. 1998), and that under certain conditions could significantly impact migrating smolt populations. Beginning in 1999, the Washington Cooperative Fish and Wildlife Research Unit (WACFWRU) was asked by the YKFP to continue development of avian consumption indices. Monitoring methods developed by Phinney et al. (1998) were adopted (with modifications) and monitoring of impacts to juvenile salmon along river reaches and at areas of high predator/prey concentrations (colloquially referred to as ''hotspots'') has continued each year through 2001. In 2001, piscivorous birds were counted from river banks at hotspots and from a raft or drift boat along river reaches. Consumption by gulls at hotspots was based on direct observations of foraging success and modeled abundance; consumption by all other piscivorous birds was estimated using published dietary requirements and modeled abundance. Seasonal patterns of avian piscivore abundance were identified, diurnal patterns of gull abundance at hotspots were identified, and predation indices were calculated for hotspots and river reaches (for both spring and summer). Changes in survey methods in 2001 included the addition of surveys in the ''Canyon'' reach during spring and altering the method of directly measuring gull feeding rates at hotspots. Primary avian predators in 2001 were &apos

Development of known-fate survival monitoring techniques for juvenile wild pigs (Sus scrofa)

Science.gov (United States)

David A. Keiter; John C. Kilgo; Mark A. Vukovich; Fred L. Cunningham; James C. Beasley

2017-01-01

Context. Wild pigs are an invasive species linked to numerous negative impacts on natural and anthropogenic ecosystems in many regions of the world. Robust estimates of juvenile wild pig survival are needed to improve population dynamics models to facilitate management of this economically and ecologically...

The effects of grading on the growth and survival of juvenile Dover sole (Solea solea L)

DEFF Research Database (Denmark)

Overton, Julia Lynne; Steenfeldt, Svend Jørgen; Pedersen, Per Bovbjerg

2010-01-01

A 3-month study was carried out to investigate the effects of grading on the overall production, growth performance and survival of juvenile Dover sole (Solea solea L.). Juvenile fish (4.0–40.4 g) were sorted into three size groups: small (4.0–15.5 g), medium (16.0–21.5 g) and large (22.0–40.5 g)...

Contrasting effects of heavy metals and hydrocarbons on larval settlement and juvenile survival in sponges

International Nuclear Information System (INIS)

Cebrian, E.; Uriz, M.J.

2007-01-01

Metals and polycyclic aromatic hydrocarbons (PAHs) contaminate sediments and waters of coastal areas threatening early stages of invertebrate development. Effects on these stages may largely determine the decline and even disappearance of invertebrate populations in polluted environments. Our study aimed to determine the possible influence of metals (Cu and Cd) and PAHs on larval settlement and consecutive survival of two widespread sponges of the Mediterranean: Crambe crambe and Scopalina lophyropoda. Larvae of both species were exposed to Cu and Cd for a short period during 1 week, and settlement and following (6 months) survival of juvenile were monitored. Short exposures to copper and cadmium at the concentrations used did not affect C. crambe settlement compared with SW control, and no effect on consecutive survival of juveniles was observed. In contrast, short pulses of copper and cadmium at the concentrations used enhanced Scopalina lophyropoda settlement and did not affect the consecutive survival of juveniles with respect to SW controls. Furthermore, experiments designed to assess the effects of short exposures to PAHs and the combined effect of contamination by Cu 2+ and PAHs on larval settlement, were conduced during 10 days on C. crambe larvae. Hydrocarbons, differently than copper and cadmium, inhibited the settlement of sponge larvae to a certain extent. The synergetic negative effect of copper and hydrocarbons on C. crambe settlers may cause a decline of populations in areas with both sources of contamination. The present study provides the only available data on toxicity of copper, cadmium and hydrocarbon toxicants on sponge larval settlement

Surgically Implanted JSATS Micro-Acoustic Transmitters Effects on Juvenile Chinook Salmon and Steelhead Tag Expulsion and Survival, 2010

Energy Technology Data Exchange (ETDEWEB)

Woodley, Christa M.; Carpenter, Scott M.; Carter, Kathleen M.; Wagner, Katie A.; Royer, Ida M.; Knox, Kasey M.; Kim, Jin A.; Gay, Marybeth E.; Weiland, Mark A.; Brown, Richard S.

2011-09-16

The purpose of this study was to evaluate survival model assumptions associated with a concurrent study - Acoustic Telemetry Evaluation of Dam Passage Survival and Associated Metrics at John Day, The Dalles, and Bonneville Dams, 2010 by Thomas Carlson and others in 2010 - in which the Juvenile Salmonid Acoustic Telemetry System (JSATS) was used to estimate the survival of yearling and subyearling Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) migrating through the Federal Columbia River Power System (FCRPS). The micro-acoustic transmitter used in these studies is the smallest acoustic transmitter model to date (12 mm long x 5 mm wide x 4 mm high, and weighing 0.43 g in air). This study and the 2010 study by Carlson and others were conducted by researchers from the Pacific Northwest National Laboratory and the University of Washington for the U.S. Army Corps of Engineers, Portland District, to meet requirements set forth by the 2008 FCRPS Biological Opinion. In 2010, we compared survival, tag burden, and tag expulsion in five spring groups of yearling Chinook salmon (YCH) and steelhead (STH) and five summer groups of subyearling Chinook salmon (SYC) to evaluate survival model assumptions described in the concurrent study. Each tagging group consisted of approximately 120 fish/species, which were collected and implanted on a weekly basis, yielding approximately 600 fish total/species. YCH and STH were collected and implanted from late April to late May (5 weeks) and SYC were collected and implanted from mid-June to mid-July (5 weeks) at the John Day Dam Smolt Monitoring Facility. The fish were collected once a week, separated by species, and assigned to one of three treatment groups: (1) Control (no surgical treatment), (2) Sham (surgical implantation of only a passive integrated transponder [PIT] tag), and (3) Tagged (surgical implantation of JSATS micro-acoustic transmitter [AT] and PIT tags). The test fish were held for 30 days in indoor

Juvenile survival in a tropical population of roseate terns: Interannual variation and effect of tick parasitism

Science.gov (United States)

Monticelli, David; Ramos, Jaime A.; Hines, James E.; Nichols, James D.; Spendelow, Jeffrey A.

2008-01-01

Many demographic studies on long-lived seabirds have focused on the estimation of adult survival, but much less is known about survival during the early years of life, especially in tropical species. We report analyses of a capture–recapture dataset of 685 roseate terns ringed as fledglings and adults between 1998 and 2005 on Aride Island, Seychelles, and recaptured/resighted at the same colony site over a 5 yr (2002 to 2006) period. A multistate model was used to estimate survival for different age classes, including juvenile (first-year) birds returning as non-breeding prospectors. The effect of infestation by parasites (ticks) on survival was also examined. Overall, the estimated return of first-year individuals to the natal colony was very variable, ranging from 2 to 22%. Conditioned on survival, the probability of returning from Age 2 yr onwards increased to 70%. Survival rates were best modeled as time-specific, with estimates varying from 0.02 to 1.00 (mean 0.69) in first-year birds with a marked negative effect of tick infestation. In older birds (minimum age of 2 yr), the annual estimates fell between 0.69 and 0.86 (mean 0.77). Using a components of variance approach for estimation of year-to-year variation, we found high temporal variability for first-year individuals (coefficient of variation [CV] = 65%) compared to much less variation in the survival rate of older birds (CV = 9%). These findings agree with the life-history prediction that demographic rates of juveniles are usually lower and more variable than those of older individuals. Our results are also consistent with the predicted negative effect of tick parasitism on juvenile survival. Compared with data from other roseate tern populations, survival over the first 2 yr (Age 0 to 2 yr) was 18 to 40% higher in this study, suggesting that a high ‘young’ survival rate may be an important demographic trait in this tropical population to compensate for the low annual reproductive success. Our

Growth and survival of Hippocampus erectus (Perry, 1810 juveniles fed on Artemia with different HUFA levels

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Nicolás Vite-Garcia

2014-03-01

Full Text Available Survival during first months after birth is one of the bottlenecks for consolidating the seahorse farming industry. In this work, Artemia metanauplii enriched with two highly unsaturated fatty acids (HUFA rich commercial emulsions with different docosahexaenoic acid (DHA levels (63% and 14% of total lipids, a vegetable oil with no DHA, and non-enriched Artemia as control, were used to feed 5-day-old juvenile Hippocampus erectus for 60 days. Enriched Artemia had similar levels of DHA (13% and 9%, despite great differences of DHA in the emulsions, with traces of DHA in non-enriched and vegetable oil enriched Artemia. More than 20% of DHA was found in 24 h starved juveniles fed both DHA-enriched treatments, similar to values in newly born juveniles, but those fed vegetable oil enriched Artemia or non-enriched Artemia had 5% of DHA. Total lipid and protein levels were similar in juveniles from the four treatments. The n-3/n-6 ratio was almost four-fold higher in seahorses fed DHA-enriched treatments compared to juveniles fed the non-enriched treatments. Survival of seahorses only partially reflected the DHA levels: it was lower in the vegetable oil treatment, similar in the seahorses fed Artemia with higher DHA and in the control treatment, and higher in seahorses fed the HUFA-enriched Artemia with lower DHA levels, although growth was similar in the two DHA-enriched Artemia treatments. Juvenile H. erectus seahorses perform better when they have at least 20% of DHA in their tissues, and these levels can be attained with no more than 14% of DHA in emulsions, eliminating the need for more expensive emulsions with higher DHA levels.

Juvenile salmon usage of the Skeena River estuary.

Science.gov (United States)

Carr-Harris, Charmaine; Gottesfeld, Allen S; Moore, Jonathan W

2015-01-01

Migratory salmon transit estuary habitats on their way out to the ocean but this phase of their life cycle is more poorly understood than other phases. The estuaries of large river systems in particular may support many populations and several species of salmon that originate from throughout the upstream river. The Skeena River of British Columbia, Canada, is a large river system with high salmon population- and species-level diversity. The estuary of the Skeena River is under pressure from industrial development, with two gas liquefaction terminals and a potash loading facility in various stages of environmental review processes, providing motivation for understanding the usage of the estuary by juvenile salmon. We conducted a juvenile salmonid sampling program throughout the Skeena River estuary in 2007 and 2013 to investigate the spatial and temporal distribution of different species and populations of salmon. We captured six species of juvenile anadromous salmonids throughout the estuary in both years, and found that areas proposed for development support some of the highest abundances of some species of salmon. Specifically, the highest abundances of sockeye (both years), Chinook in 2007, and coho salmon in 2013 were captured in areas proposed for development. For example, juvenile sockeye salmon were 2-8 times more abundant in the proposed development areas. Genetic stock assignment demonstrated that the Chinook salmon and most of the sockeye salmon that were captured originated from throughout the Skeena watershed, while some sockeye salmon came from the Nass, Stikine, Southeast Alaska, and coastal systems on the northern and central coasts of British Columbia. These fish support extensive commercial, recreational, and First Nations fisheries throughout the Skeena River and beyond. Our results demonstrate that estuary habitats integrate species and population diversity of salmon, and that if proposed development negatively affects the salmon populations that

EFFECTS OF DIFFERENT TYPES OF FEED ON GROWTH, SURVIVAL AND DIGESTIVE ENZYME ACTIVITY OF EARLY JUVENILE-STAGE MARBLE GOBY, Oxyeleotris marmoratus

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Muhammad Darwis

2008-06-01

Full Text Available The stable mass seed production technique of marble goby, Oxyeleotris marmoratus has not yet been established due to high mortality occurring on the early juvenile stage and/or after 40 days after hatching (d AH. In order to establish the mass seed production technique, O. marmoratus juveniles of 40 d AH were reared for 60 days to determine growth, survival and digestive enzyme activity at different types of feed (trash fish, artificial feed and Artemia sp. nauplii. Specific growth rate (5.32 and survival rate (91.3% in juveniles fed Artemia sp. nauplii showed significantly higher (P<0.05 than those of juveniles fed trash fish and artificial feed. At the end of the experiment, the mean specific trypsin, amylase and lipase activities of juveniles fed Artemia sp. nauplii were recorded as 0.04 mU mg protein-1m-1, 0.114 mg maltose mg protein-1h-1 and 9.58 m Units, respectively, and they were significantly higher than those of juveniles fed trash fish and artificial feed. In the present study it was shown that O. marmoratus early juveniles had more efficient digestibility and absorption the nutrient when fed with Artemia.

Trophic feasibility of reintroducing anadromous salmonids in three reservoirs on the north fork Lewis River, Washington: Prey supply and consumption demand of resident fishes

Science.gov (United States)

Sorel, Mark H.; Hansen, Adam G.; Connelly, Kristin A.; Beauchamp, David A.

2016-01-01

The reintroduction of anadromous salmonids in reservoirs is being proposed with increasing frequency, requiring baseline studies to evaluate feasibility and estimate the capacity of reservoir food webs to support reintroduced populations. Using three reservoirs on the north fork Lewis River as a case study, we demonstrate a method to determine juvenile salmonid smolt rearing capacities for lakes and reservoirs. To determine if the Lewis River reservoirs can support reintroduced populations of juvenile stream-type Chinook Salmon Oncorhynchus tshawytscha, we evaluated the monthly production of daphniaDaphnia spp. (the primary zooplankton consumed by resident salmonids in the system) and used bioenergetics to model the consumption demand of resident fishes in each reservoir. To estimate the surplus of Daphnia prey available for reintroduced salmonids, we assumed a maximum sustainable exploitation rate and accounted for the consumption demand of resident fishes. The number of smolts that could have been supported was estimated by dividing any surplus Daphnia production by the simulated consumption demand of an individual Chinook Salmon fry rearing in the reservoir to successful smolt size. In all three reservoirs, densities of Daphnia were highest in the epilimnion, but warm epilimnetic temperatures and the vertical distribution of planktivores suggested that access to abundant epilimnetic prey was limited. By comparing accessible prey supply and demand on a monthly basis, we were able to identify potential prey supply bottlenecks that could limit smolt production and growth. These results demonstrate that a bioenergetics approach can be a valuable method of examining constraints on lake and reservoir rearing capacity, such as thermal structure and temporal food supply. This method enables numerical estimation of rearing capacity, which is a useful metric for managers evaluating the feasibility of reintroducing Pacific salmon Oncorhynchus spp. in lentic systems.

Diurnal stream habitat use of juvenile Atlantic salmon, brown trout and rainbow trout in winter

Science.gov (United States)

Johnson, J. H.; Douglass, K.A.

2009-01-01

The diurnal winter habitat of three species of juvenile salmonids was examined in a tributary of Skaneateles Lake, NY to compare habitat differences among species and to determine if species/age classes were selecting specific habitats. A total of 792 observations were made on the depth, velocity, substrate and cover (amount and type) used by sympatric subyearling Atlantic salmon, subyearling brown trout and subyearling and yearling rainbow trout. Subyearling Atlantic salmon occurred in shallower areas with faster velocities and less cover than the other salmonid groups. Subyearling salmon was also the only group associated with substrate of a size larger than the average size substrate in the study reach during both winters. Subyearling brown trout exhibited a preference for vegetative cover. Compared with available habitat, yearling rainbow trout were the most selective in their habitat use. All salmonid groups were associated with more substrate cover in 2002 under high flow conditions. Differences in the winter habitat use of these salmonid groups have important management implications in terms of both habitat protection and habitat enhancement.

Expert initial review of Columbia River Basin salmonid management models: Summary report

International Nuclear Information System (INIS)

Barnthouse, L.W.

1993-10-01

Over the past years, several fish passage models have been developed to examine the downstream survival of salmon during their annual migration through the Columbia River reservoir system to below Bonneville Dam. More recently, models have been created to simulate the survival of salmon throughout the entire life cycle. The models are used by various regional agencies and native American tribes to assess impacts of dam operation, harvesting, and predation on salmonid abundance. These models are now also being used to assess extinction probabilities and evaluate restoration alternatives for threatened and endangered salmonid stocks. Oak Ridge National Laboratory (ORNL) coordinated an initial evaluation of the principal models by a panel of outside, expert reviewers. None of the models were unequivocally endorsed by any reviewer. Significant strengths and weaknesses were noted for each with respect to reasonability of assumptions and equations, adequacy of documentation, adequacy of supporting data, and calibration procedures. Although the models reviewed differ in some important respects, all reflect a common conceptual basis in classical population dynamic theory and a common empirical basis consisting of the available time series of salmonid stock data, hydrographic records, experimental studies of dam passage parameters, and measurements of reservoir mortality. The results of this initial review are not to be construed as a comprehensive scientific peer review of existing Columbia River Basin (CRB) salmon population models and data. The peer review process can be enhanced further by a dynamic exchange regional modelers and scientific panel experts involving interaction and feedback

Trapping and transportation of adult and juvenile salmon in the lower Umatilla River in northeast Oregon, 1995--1996 -- Umatilla River Basin Trap and Haul Program. Annual progress report, October 1995--September 1996

International Nuclear Information System (INIS)

Zimmerman, B.C.; Duke, B.B.

1996-09-01

Threemile Falls Dam (Threemile Dam), located near the town of Umatilla, is the major collection and counting point for adult salmonids returning to the Umatilla River. Returning salmon and steelhead were collected at Threemile Dam from September 5, 1995 to July 1, 1996. A total of 2,081 summer steelhead (Oncorhynchus mykiss); 603 adult, 288 jack, and 338 subjack fall chinook (O. tshawytscha); 946 adult and 53 jack coho (O. kisutch); and 2,152 adult and 121 jack spring chinook (O. tshawytscha) were collected. All fish were trapped at the east bank facility. The Westland Canal juvenile facility (Westland), located near the town of Echo at rivermile (RM) 27, is the major collection point for outmigrating juvenile salmonids and steelhead kelts. The Threemile Dam west bank juvenile bypass was operated from September 8 to October 13, 1995 and from March 18 to June 30, 1996. The juvenile trap was operated from July 1 to July 11. Daily operations at the facility were conducted by the ODFW Fish Passage Research project to monitor juvenile outmigration

Annual Report to the Bonneville Power Administration, Reporting Period: April 2008 - February 2009 [re: "Survival and Growth in the Columbia River Plume and north California Current"].

Energy Technology Data Exchange (ETDEWEB)

Northwest Fisheries Science Center, NOAA Fisheries; Cooperative Institute for Marine Resources Studies, Oregon State University; OGI School of Science & Engineering, Oregon Health Sciences University.

2009-07-17

We have made substantial progress toward our objectives outlined in our BPA supported proposal entitled 'Columbia River Basin Juvenile Salmonids: Survival and Growth in the Columbia River Plume and northern California Current' which we report on herein. During 2008, we were able to successfully conduct 3 mesoscale cruises. We also were able to conduct 7 biweekly predator cruises, along with substantial shore-based visual observations of seabirds. Detailed results of the mesoscale cruises are available in the Cruise Reports and summarized in the next section. We have taken a proactive approach to getting the results of our research to fisheries managers and the general public. We have begun to make annual predictions based on ocean conditions of the relative survival of juvenile coho and Chinook salmon well before they return as adults. This is based on both biological and physical indicators that we measure during our surveys or collect from outside data sources. Examples of our predictions for 2009 and 2010 are available on the following web site: http://www.nwfsc.noaa.gov/research/divisions/fed/oeip/a-ecinhome.cfm.

Juvenile survival in a neotropical migratory songbird is lower than expected.

Directory of Open Access Journals (Sweden)

Matthew I McKim-Louder

Full Text Available Attempts to estimate and identify factors influencing first-year survival in passerines, survival between fledging and the first reproductive attempt (i.e. juvenile survival, have largely been confounded by natal dispersal, particularly in long-distance migratory passerines. We studied Prothonotary Warblers (Protonotaria citrea breeding in nest boxes to estimate first-year survival while accounting for biases related to dispersal that are common in mark-recapture studies. The natal dispersal distribution (median = 1420 m; n = 429 and a distance-dependent recruitment rate, which controls for effects of study site configuration, both indicated a pattern of short-distance natal dispersal. This pattern was consistent with results of a systematic survey for birds returning outside the nest box study sites (up to 30 km in all directions within a majority (81% of total available bottomland forest habitat, further suggesting that permanent emigration outside of the study system was rare. We used multistate mark-recapture modeling to estimate first-year survival and incorporated factors thought to influence survival while accounting for the potential confounding effects of dispersal on recapture probabilities for warblers that fledged during 2004-2009 (n = 6093. Overall, the average first-year survival for warblers reared without cowbird nestmates was 0.11 (95% CI = 0.09-0.13, decreased with fledging date (0.22 early to 0.03 late and averaged 40% lower for warblers reared with a brood parasite nestmate. First-year survival was less than half of the rate thought to represent population replacement in migratory passerines (∼0.30. This very low rate suggests that surviving the first year of life for many Neotropical migratory species is even more difficult than previously thought, forcing us to rethink estimates used in population models.

Gauging resource exploitation by juvenile Chinook salmon (Oncorhynchus tshawytscha) in restoring estuarine habitat

Science.gov (United States)

Davis, Melanie; Ellings, Christopher S.; Woo, Isa; Hodgson, Sayre; Larsen, Kimberly A.; Nakai, Glynnis

2018-01-01

In the context of delta restoration and its impact on salmonid rearing, success is best evaluated based on whether out-migrating juvenile salmon can access and benefit from suitable estuarine habitat. Here, we integrated 3 years of post-restoration monitoring data including habitat availability, invertebrate prey biomass, and juvenile Chinook salmon (Oncorhynchus tshawytscha) physiological condition to determine whether individuals profited from the addition of 364 ha of delta habitat in South Puget Sound, Washington, United States. Productivity in the restored mudflat was comparable to reference sites 3 years after dike removal, surpassing a mean total of 6 million kJ energy from invertebrate prey. This resulted from the development of a complex network of tidal channels and a resurgence in dipteran biomass that was unique to the restoration area. Consequently, a notable shift in invertebrate consumption occurred between 2010 and 2011, whereby individuals switched from eating primarily amphipods to dipteran flies; however, dietary similarity to the surrounding habitat did not change from year to year, suggesting that this shift was a result of a change in the surrounding prey communities. Growth rates did not differ between restored and reference sites, but catch weight was positively correlated with prey biomass, where greater prey productivity appeared to offset potential density-dependent effects. These results demonstrate how the realized function of restoring estuarine habitat is functionally dependent. High prey productivity in areas with greater connectivity may support healthy juvenile salmon that are more likely to reach the critical size class for offshore survival.

Epidemiology and Control of Infectious Diseases of Salmonids in the Columbia River Basin, 1983 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Fryer, John L.

1984-11-01

The Department of Microbiology at Oregon State University with funding from the Bonneville Power Administration conducted a study relating to the epidemiology and control of three fish diseases of salmonids in the Columbia River Basin. These three diseases were ceratomyxosis which is caused by the myxosporidan parasite Ceratomyxa shasta, bacterial kidney disease, the etiological agent of which is Renibacterium salmoninarum, and infectious hematopoietic necrosis, which is caused by a rhabdovirus. Each of these diseases is highly destructive and difficult or impossible to treat with antimicrobial agents. The presence of ceratomyxosis in rainbow trout exposed at McNary and Little Goose Dams extends the range of this disease about 200 miles further up the Columbia River and into the Snake River drainage. Wallowa steelhead trout were less resistant to this disease than other upriver stocks tested. Juvenile salmonids entering the Columbia River estuary were collected periodically between May to September, 1983. Nine percent of the beach seined chinook salmon and 5, 11 and 12%, respectively, of the purse seined coho and chinook salmon and steelhead trout were infected with Ceratomyxa shasta. Experiments indicated ceratomyxosis progresses in salt water at the same rate as in fresh water once the fish have become infected. These data indicate a longer exposure to infective stages of C. shasta than previously identified and that approximately 10% of the migrating salmonids are infected and will probably die from this organism after entering salt water. Since sampling began in 1981 the bacterial kidney disease organism, Renibacterium salmoninarum, has been detected by the fluorescent antibody test in seven salmonid species caught in the open ocean off the coasts of Washington and Oregon. The bacterium has been found primarily in chinook salmon (11%) with lesions in 2.5% of these fish. This disease was also detected at levels ranging from 17% in coho salmon to 25% in chinook

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

Evaluation of an ion adsorption method to estimate intragravel flow velocity in salmonid spawning gravels

Science.gov (United States)

James L. Clayton; John G. King; Russell F. Thurow

1996-01-01

Intragravel water exchange provides oxygenated water, removes metabolic waste, and is an essential factor in salmonid embryo survival. Measurements of intragravel flow velocity have been suggested as an index of gravel quality and also as a useful predictor of fry emergence; however, proposed methods for measuring velocity in gravel are problematic. We evaluate an ion...

Reservoir drawdown: Case study in flow changes to potentially improve fisheries

International Nuclear Information System (INIS)

Wik, S.J.

1995-01-01

Salmon populations in the Columbia River Basin have declined, and several species are now protected under the Endangered Species Act. Many factors have contributed to the decline, including overharvest, loss of habit, degradation of water quality, and construction of dams. Many measures have been implemented to reduce the impact of the dams, but additional measures are being considered. Lowering water-surface elevations behind four lower Snake River dams has been proposed as a measure to improve juvenile salmonid survival. The Corps of Engineers has determined preliminary costs, schedules, and required modifications for several drawdown alternatives. Initial estimates of the ability of this type of operation to improve salmonid survival are controversial

Effects of calanoid copepod Schmackeria poplesia as a live food on the growth, survival and fatty acid composition of larvae and juveniles of Japanese flounder, Paralichthys olivaceus

Science.gov (United States)

Liu, Guangxing; Xu, Donghui

2009-12-01

Zooplankton constitutes a major part of the diet for fish larvae in the marine food web, and it is generally believed that copepods can meet the nutritional requirements of fish larvae. In this study, calanoid copepod Schmackeria poplesia, rotifer Brachionus plicatilis and anostraca crustacean Artemia sp. were analyzed for fatty acid contents, and were used as live food for culturing larval Japanese flounder, Paralichthys olivaceus. The total content of three types of HUFAs (DHA, EPA and ARA) in S. poplesia was significantly higher than that in the other two live foods ( P<0.01). Three live organisms were used for raising larvae and juveniles of Paralichthys olivaceus respectively for 15 and 10 d. Then the growth, survival and fatty acid composition of the larvae and juveniles were investigated. The results showed that the larvae and juveniles fed with copepods ( S. poplesia) had significantly higher growth rate than those fed with the other two organisms ( P<0.01). The survival of the flounder larvae fed with copepods was significantly higher than that of the others ( P<0.01), and the survival of the juvenile fish fed with copepods was higher than that fed with Artemia ( P<0.05). The contents of three types of HUFAs (DHA, EPA and ARA) and the ratio of DHA/EPA in larval and juvenile flounder P. olivaceus were analyzed. The results showed that the contents of DHA, EPA and ARA in the larvae and juveniles fed with S. poplesia were higher than those fed with a mixed diet or Artemia only, and the ratio of EPA/ARA in larvae and juveniles of P. olivaceus fed with S. poplesia was lower than that in the case of feeding with a mixed diet or Artemia only. The present data showed that copepod is the best choice for feeding the larvae and juveniles of fish considering its effects on the survival, growth and nutrition composition of the fish.

Habitat selection influences sex distribution, morphology, tissue biochemistry, and parasite load of juvenile coho salmon in the West Fork Smith River, Oregon

Science.gov (United States)

Given the strong influence of water temperature on salmonid physiology and behavior, in the summers of 2004 and 2005 we studied juvenile male and female coho salmon Oncorhynchus kisutch in two reaches of Oregon’s West Fork Smith River with different thermal profiles. Our goals we...

Survival, growth performance and immune capacity of the juvenile lined seahorse Hippocampus erectus fed with rifampicin-treated copepods.

Science.gov (United States)

Lin, Tingting; Wang, Changbo; Liu, Xin; Gao, Fen; Xiao, Dongxue; Zhang, Dong; Zhu, Xialian

2017-06-19

Gastrointestinal disease is one of the most serious diseases in cultured seahorse juveniles. Treatment with antimicrobials of live food (i.e. copepods and Artemia) that is used to feed the juveniles may be a promising measure to alleviate the occurrence of gastrointestinal disease. However, relevant investigations are rare. In the present study, we first investigated the antimicrobial efficacies on bacteria within copepods that were treated with 4 antimicrobials, including 3 antibiotics (i.e. enrofloxacin hydrochloride, oxytetracycline and rifampicin [RFP]) that are approved for use in aquaculture and 1 disinfectant (i.e. povidone iodine). We then assessed the effects of copepods treated with the antimicrobial that had the best antimicrobial efficacy on survival, growth performance and immune capacity of juvenile lined seahorses Hippocampus erectus. The results showed that RFP had the best antimicrobial efficacy on both Pseudoalteromonas spp. and Vibrio spp., 2 dominant bacteria with potential pathogenicity within the copepods; the proper concentration of RFP was 6 mg l-1. Moreover, H. erectus juveniles fed with RFP-treated copepods demonstrated an improved survivorship and immune capacity and had a lower abundance of pathogenic bacteria within their gastrointestinal tracts compared to juveniles fed with untreated copepods. These results suggest that treating live food with RFP is a potential measure for reducing the incidence of gastrointestinal disease in seahorse juveniles.

Comparison of infectious hematopoietic necrosis in natural and experimental infections of spawning salmonids by infectivity and immunohistochemistry

Science.gov (United States)

Yamamoto, T.; Arakawa, C.K.; Batts, W.N.; Winton, J.R.

1989-01-01

Infectious hematopoietic necrosis (IHN) continues to be a serious virus disease of salmonids with epizootics recorded in both wild and hatchery populations (Williams and Amend 1976; Carlisle et al 1979; Groberg and Fryer 1983; Saft and Pratt 1986; Traxler 1987; Follett et al 1987; Meyers et al 1988). While originally enzootic in western North America, the virus appears to be spreading further (Sano et al 1977; de Kinkelin et al 1987; Bovo et al 1987). In hatchery outbreaks occurring in regions where the virus is not enzootic, it is often possible to trace the virus to the importation of infected fingerlings or contaminated eggs. In regions where the virus is widespread among stocks of fish, the source of virus infection is more difficult to establish particularly in watersheds where there are anadromous salmonids. Although salmonid fish surviving infection as fry and returning from the ocean to spawn are considered to be parental carriers of IHNV, there is very little data to support this hypothesis. Amend (1975) in the study of rainbow trout reported that in a population surviving infection and assayed a few years later found that a few trout were carrying virus. This is the study often cited as evidence for the carrier status of returning salmonids. LaPatra et al (1987) presented data that indicated IHNV has been transmitted horizontally through water from adult chinook salmon (Oncorhynchus tshawytscha) to adult coho salmon (O. kisutch) at a hatchery in northern California. They suggested that horizontal transmission may be an important means for perpetuating IHN. However, the actual mechanisms for persistence and transmission of IHN among fish in a watershed is likely to be complex and involve multiple species and age groups as well as intermediate vectors and/or reservoirs.

Detection and quantification of Renibacterium salmoninarum DNA in salmonid tissues by real-time quantitative polymerase chain reaction analysis

Science.gov (United States)

Chase, D.M.; Elliott, D.G.; Pascho, R.J.

2006-01-01

Renibacterium salmoninarum is an important salmonid pathogen that is difficult to culture. We developed and assessed a real-time, quantitative, polymerase chain reaction (qPCR) assay for the detection and enumeration of R. salmoninarum. The qPCR is based on TaqMan technology and amplifies a 69-base pair (bp) region of the gene encoding the major soluble antigen (MSA) of R. salmoninarum. The qPCR assay consistently detected as few as 5 R. salmoninarum cells per reaction in kidney tissue. The specificity of the qPCR was confirmed by testing the DNA extracts from a panel of microorganisms that were either common fish pathogens or reported to cause false-positive reactions in the enzyme-linked immunosorbent assay (ELISA). Kidney samples from 38 juvenile Chinook salmon (Oncorhynchus tshawytscha) in a naturally infected population were examined by real-time qPCR, a nested PCR, and ELISA, and prevalences of R. salmoninarum detected were 71, 66, and 71%, respectively. The qPCR should be a valuable tool for evaluating the R. salmoninarum infection status of salmonids.

Acoustic Telemetry Studies of Juvenile Chinook Salmon Survival at the Lower Columbia Projects in 2006

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R.; Weiland, Mark A.; Hughes, James S.; Zimmerman, Shon A.; Durham, Robin E.; Fischer, Eric S.; Kim, Jina; Townsend, Richard L.; Skalski, John R.; McComas, Roy L.

2008-02-01

The Portland District of the U.S. Army Corps of Engineers contracted with the Pacific Northwest National Laboratory (PNNL) to conduct three studies using acoustic telemetry to estimate detection probabilities and survival of juvenile Chinook salmon at three hydropower projects on the lower Columbia River. The primary goals were to estimate detection and survival probabilities based on sampling with JSATS equipment, assess the feasibility of using JSATS for survival studies, and estimate sample sizes needed to obtain a desired level of precision in future studies. The 2006 JSATS arrays usually performed as well or better than radio telemetry arrays in the JDA and TDA tailwaters, and underperformed radio arrays in the BON tailwater, particularly in spring. Most of the probabilities of detection on at least one of all arrays in a tailwater exceeded 80% for each method, which was sufficient to provide confidence in survival estimates. The probability of detection on one of three arrays includes survival and detection probabilities because fish may die or pass all three arrays undetected but alive.

An epidemiological model of virus transmission in salmonid fishes of the Columbia River Basin

Science.gov (United States)

Ferguson, Paige F. B.; Breyta, Rachel; Brito, Ilana L.; Kurath, Gael; LaDeau, Shannon L.

2018-01-01

cohort-sites experienced self-exposure by infected juvenile fish, this transmission route had the greatest probability of infection (0.22). Increased testing and/or determining whether transmission can occur from cohort-sites without testing records (e.g., determining there was no testing record because there were no fish at the cohort-site) are expected to improve inference about infection probabilities. Increased use of secure water supplies and continued use of biosecurity protocols may reduce IHNV transmission from adult fish and juvenile fish within the site, respectively, to juvenile salmonids at hatcheries. Models and conclusions from this study are potentially relevant to understanding the relative importance of transmission routes for other important aquatic pathogens in salmonids, including the agents of bacterial kidney disease and coldwater disease, and the basic approach may be useful for other pathogens and hosts in other geographic regions.

Exposure-related effects of Zequanox on juvenile lake sturgeon (Acipenser fulvescens) and lake trout (Salvelinus namaycush)

Science.gov (United States)

Luoma, James A.; Severson, Todd J.; Wise, Jeremy K.; Barbour, Matthew

2018-01-01

The environmental fate, persistence, and non-target animal impacts of traditional molluscicides for zebra, Dreissena polymorpha, and quagga, D. bugensis, mussel control led to the development of the biomolluscicide Zequanox. Although previous research has demonstrated the specificity of Zequanox, one study indicated sensitivity of salmonids and lake sturgeon, Acipenser fulvescens, following non-label compliant exposures to Zequanox. This study was conducted to evaluate sublethal and lethal impacts of Zequanox exposure on juvenile lake sturgeon and lake trout, Salvelinus namaycush, following applications that were conducted in a manner consistent with the Zequanox product label. Fish were exposed to 50 or 100 mg/L of Zequanox as active ingredient for 8 h and then held for 33 d to evaluate latent impacts. No acute mortality was observed in either species; however, significant latent mortality (P < 0.01, df = 9; 46.2%) was observed in lake trout that were exposed to the highest dose of Zequanox. Statistically significant (P < 0.03, df = 9), but biologically minimal differences were observed in the weight (range 20.17 to 21.49 g) of surviving lake sturgeon at the termination of the 33 d post-exposure observation period. Statistically significant (P < 0.05, df = 9) and biologically considerable differences were observed in the weight (range 6.19 to 9.55 g) of surviving lake trout at the termination of the 33 d post-exposure observation period. Histologic evaluation of lake trout gastrointestinal tracts suggests that the mode of action in lake trout is different from the mode of action that induces zebra and quagga mussel mortality. Further research could determine the sensitivity of other salmonid species to Zequanox and determine if native fish will avoid Zequanox treated water.

Effects of food restriction across stages of juvenile and early adult development on body weight, survival and adult life history.

Science.gov (United States)

Wong, J W Y; Kölliker, M

2014-11-01

Organisms have to allocate limited resources among multiple life-history traits, which can result in physiological trade-offs, and variation in environmental conditions experienced during ontogeny can influence reproduction later in life. Food restriction may lead to an adaptive reallocation of the limited resources among traits as a phenotypically plastic adjustment, or it can act as an overall constraint with detrimental effects throughout reproductive life. In this study, we investigated experimentally the effects of food restriction during different stages of the juvenile and early adult development on body weight, survival and reproductive success in females and males of the European earwig Forficula auricularia. Individuals either received limited or unlimited access to food across three different stages of development (fully crossed) allowing us to identify sensitive periods during development and to test both additive and interactive effects of food limitation across stages on development and reproduction. Food restriction during the early and late juvenile stage had additive negative effects on juvenile survival and adult body weight. With regard to reproductive success of females which produce up to two clutches in their lifetime, restriction specifically in the late juvenile stage led to smaller first and second clutch size, lower probability of second clutch production and reduced hatching success in the second clutch. Reproductive success of females was not significantly affected when their male mates experienced food restriction during their development. Our findings in general support the 'silver-spoon' hypothesis in that food restriction during juvenile development poses constraints on development and reproduction throughout life. © 2014 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

Culture of salmonid fishes

National Research Council Canada - National Science Library

Stickney, Robert R

1991-01-01

.... In recognition of the growing concern that aquaculture development has the potential to negatively impact the natural environment, a chapter on controversies surrounding salmonid culture has been included...

First Direct Evidence for Natal Wintering Ground Fidelity and Estimate of Juvenile Survival in the New Zealand Southern Right Whale Eubalaena australis.

Science.gov (United States)

Carroll, E L; Fewster, R M; Childerhouse, S J; Patenaude, N J; Boren, L; Baker, C S

2016-01-01

Juvenile survival and recruitment can be more sensitive to environmental, ecological and anthropogenic factors than adult survival, influencing population-level processes like recruitment and growth rate in long-lived, iteroparous species such as southern right whales. Conventionally, Southern right whales are individually identified using callosity patterns, which do not stabilise until 6-12 months, by which time the whale has left its natal wintering grounds. Here we use DNA profiling of skin biopsy samples to identify individual Southern right whales from year of birth and document their return to the species' primary wintering ground in New Zealand waters, the Subantarctic Auckland Islands. We find evidence of natal fidelity to the New Zealand wintering ground by the recapture of 15 of 57 whales, first sampled in year of birth and available for subsequent recapture, during winter surveys to the Auckland Islands in 1995-1998 and 2006-2009. Four individuals were recaptured at the ages of 9 to 11, including two females first sampled as calves in 1998 and subsequently resampled as cows with calves in 2007. Using these capture-recapture records of known-age individuals, we estimate changes in survival with age using Cormack-Jolly-Seber models. Survival is modelled using discrete age classes and as a continuous function of age. Using a bootstrap method to account for uncertainty in model selection and fitting, we provide the first direct estimate of juvenile survival for this population. Our analyses indicate a high annual apparent survival for juveniles at between 0.87 (standard error (SE) 0.17, to age 1) and 0.95 (SE 0.05: ages 2-8). Individual identification by DNA profiling is an effective method for long-term demographic and genetic monitoring, particularly in animals that change identifiable features as they develop or experience tag loss over time.

Influence of infection with Renibacterium salmoninarum on susceptibility of juvenile spring chinook salmon to gas bubble trauma

Science.gov (United States)

Weiland, L.K.; Mesa, M.G.; Maule, A.G.

1999-01-01

During experiments in our laboratory to assess the progression and severity of gas bubble trauma (GBT) in juvenile spring chinook salmon Oncorhynchus tshawytscha, we had the opportunity to assess the influence of Renibacterium salmoninarum (Rs), the causative agent of bacterial kidney disease, on the susceptibility of salmon to GBT. We exposed fish with an established infection of Rs to 120% total dissolved gas (TDG) for 96 h and monitored severity of GBT signs in the fins and gills, Rs infection level in kidneys by using an enzyme-linked immunosorbent assay (ELISA), and mortality. Mortality occurred rapidly after exposure to 120% TDG, with a LT20 (time necessary to kill 20% of the population) of about 37 h, which is at a minimum about 16% earlier than other bioassays we have conducted using fish that had no apparent signs of disease. Fish that died early (from 31 to 36 h and from 49 to 52 h) had significantly higher infection levels (mean ?? SE ELISA absorbance = 1.532 ?? 0.108) than fish that survived for 96h (mean ?? SE ELISA absorbance = 0.828 ?? 0.137). Fish that died early also had a significantly greater number of gill filaments occluded with bubbles than those that survived 96 h. Conversely, fish that survived for 96 h had a significantly higher median fin severity ranking than those that died early. Our results indicate that fish with moderate to high levels of Rs infection are more vulnerable to the effects of dissolved gas supersaturation (DGS) and die sooner than fish with lower levels of Rs infection. However, there is a substantial amount of individual variation in susceptibility to the apparent cumulative effects of DGS and Rs infection. Collectively, our findings have important implications to programs designed to monitor the prevalence and severity of GBT in juvenile salmonids in areas like the Columbia River basin and perhaps elsewhere.

Predation on Pacific salmonid eggs and carcass's by subyearling Atlantic salmon in a tributary of Lake Ontario

Science.gov (United States)

Johnson, James H.; Chalupnicki, Marc A.; Abbett, Ross; Verdoliva, Francis

2016-01-01

A binational effort to reintroduce Atlantic salmon (Salmo salar) that were extirpated in the Lake Ontario ecosystem for over a century is currently being undertaken by the New York State Department of Environmental Conservation and the Ontario Ministry of Natural Resources. Reintroduction actions include the release of several life stages including fry, fall fingerlings, and yearling smolts. In this study we describe the diet of recently released fall fingerling Atlantic salmon in a tributary of the Salmon River, New York. A specific objective of the study was to determine if juvenile Atlantic salmon would utilize the high caloric food source provided by introduced Pacific salmonids (Oncorhynchus spp.) that includes eggs and carcass flesh. Salmon eggs and carcass flesh comprised 20.5% of the October to January diet in 2013–14 and 23.9% in 2014–15. The consumption of steelhead (O. mykiss) eggs was a major part of the diet in April in both 2014 (54.1%) and 2015 (33.2%). This study documented that recently released Atlantic salmon will consume the high caloric food material provided by Pacific salmonids and that the consumption of this material extends for several months.

Trapping and transportation of adult and juvenile salmon in the lower Umatilla River in northeast Oregon, 1996-1997. Umatilla River Basin Trap and Haul Program. Annual progress report, October 1996 - September 1997

International Nuclear Information System (INIS)

Zimmerman, B.; Duke, B.B.

1997-09-01

Threemile Falls Dam (Threemile Dam), located near the town of Umatilla, is the major collection and counting point for adult salmonids returning to the Umatilla River. Returning salmon and steelhead were collected at Threemile Dam from August 30, 1996 to August 26, 1997. A total of 2,477 summer steelhead (Oncorhynchus mykiss); 646 adult, 80 jack, and 606 subjack fall chinook (O. tshawytscha); 618 adult and 24 jack coho (O. kisutch); and 2,194 adult and four jack spring chinook (O. tshawytscha) were collected. All fish were trapped at the east bank facility. Of the fish collected, 22 summer steelhead; 18 adult and two jack fall chinook; five adult coho; and 407 adult and three jack spring chinook were hauled upstream from Threemile Dam. There were 2,245 summer steelhead; 70 adult, 51 jack and 520 subjack fall chinook; 593 adult and 24 jack coho; and 1,130 adult spring chinook released at Threemile Dam I In addition, 110 summer steelhead; 551 adult and 25 jack fall chinook; and 600 adult spring chinook were collected for broodstock. The Westland Canal juvenile facility (Westland), located near the town of Echo at rivermile (RM) 27, is the major collection point for outmigrating juvenile salmonids and steelhead kelts, The canal was open for a total of 210 days between December 16, 1996 and July 30, 1997. During that period, fish were bypassed back to the river 175 days and were trapped on 35 days, An estimated 1,675 pounds of juvenile fish were transported from Westland to the Umatilla River boat ramp (RM 0.5), Approximately 80% of the juveniles transported were salmonids, No steelhead kelts were hauled from Westland this year. The Threemile Dam west bank juvenile bypass was operated from October 4 to November 1, 1996 and from March 26 to July 7, 1997. The juvenile trap was not operated this year. 6 refs., 6 figs., 6 tabs

Epidemiology and Control of Infectious Diseases of Salmonids in the Columbia River Basin, 1986 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Fryer, John L.

1986-12-01

The Department of Microbiology at Oregon State University with funding from the Bonneville Power Administration conducted a study relating to the epidemiology and control of three fish diseases of salmonids in the Columbia River Basin. These three diseases were ceratomyxosis caused by the myxosporidan parasite Ceratomyxa Shasta, bacterial kidney disease, the causative agent Renibacterium salmoninarum, and infectious hematopoietic necrosis, caused by a rhabdovirus. Each of these diseases is highly destructive and difficult or impossible to treat with antimicrobial agents. The geographic range of the infectious stage of C. Shasta has been extended to include the Snake River to the Oxbow and Hells Canyon Dams. These are the farthest upriver sites tested. Infections of ceratomyxosis were also initiated in the east fork of the Lewis River and in the Washougal River in Washington. Laboratory studies with this parasite failed to indicate that tubeficids are required in its life cycle. Bacterial kidney disease has been demonstrated in all life stages of salmonids: in the eggs, fry, smolts, juveniles and adults in the ocean, and in fish returning to fresh water. Monoclonal antibodies produced against R. salmoninarum demonstrated antigenic differences among isolates of the bacterium. Monoclonal antibodies also showed antigens of R. salmoninarum which are similar to those of a wide variety of gram positive and gram negative bacteria. A demonstration project at Round Butte Hatchery showed U V treatment to be an effective method for reducing the microbial population of the water supply and could reduce risks of IHNV. Tangential flow filtration was used successfully to concentrate IHNV from environmental water. At Round Butte Hatchery the carrier rate of IHNV in adults was very low and there was no subsequent mortality resulting from IHN in juveniles.

A simple model that identifies potential effects of sea-level rise on estuarine and estuary-ecotone habitat locations for salmonids in Oregon, USA.

Science.gov (United States)

Flitcroft, Rebecca; Burnett, Kelly; Christiansen, Kelly

2013-07-01

Diadromous aquatic species that cross a diverse range of habitats (including marine, estuarine, and freshwater) face different effects of climate change in each environment. One such group of species is the anadromous Pacific salmon (Oncorhynchus spp.). Studies of the potential effects of climate change on salmonids have focused on both marine and freshwater environments. Access to a variety of estuarine habitat has been shown to enhance juvenile life-history diversity, thereby contributing to the resilience of many salmonid species. Our study is focused on the effect of sea-level rise on the availability, complexity, and distribution of estuarine, and low-freshwater habitat for Chinook salmon (Oncorhynchus tshawytscha), steelhead (anadromous O. mykiss), and coho salmon (O. kisutch) along the Oregon Coast under future climate change scenarios. Using LiDAR, we modeled the geomorphologies of five Oregon estuaries and estimated a contour associated with the current mean high tide. Contour intervals at 1- and 2-m increments above the current mean high tide were generated, and changes in the estuary morphology were assessed. Because our analysis relied on digital data, we compared three types of digital data in one estuary to assess the utility of different data sets in predicting the changes in estuary shape. For each salmonid species, changes in the amount and complexity of estuarine edge habitats varied by estuary. The simple modeling approach we applied can also be used to identify areas that may be most amenable to pre-emptive restoration actions to mitigate or enhance salmonid habitat under future climatic conditions.

Dispersal and survival rates of adult and juvenile Red-tailed tropicbirds (Phaethon rubricauda exposed to potential contaminants

Directory of Open Access Journals (Sweden)

Schreiber, E. A.

2004-06-01

Full Text Available Annual survival and dispersal rates of adult and juvenile red-tailed tropicbirds were examined in connection with exposure to heavy metals. From 1990-2000 the incineration of a U.S. stockpile of chemical weapons stored at Johnston Atoll exposed nesting tropicbirds to increased levels of human disturbance, smoke stack emissions and potential leaks. Using a multi-state mark-recapture modeling approach, birds nesting in this site (downwind of the plant were compared to those nesting in a reference site (upwind of the plant with less human disturbance, no exposure to smoke stack emissions or other potential incineration emissions. We did not find any difference in survival of adults or juveniles when comparing the two sites. Adult breeding dispersal rates did not differ between the sites but we did find differences in the age-specific natal dispersal rates. Birds fledged from downwind areas were less likely to return to their natal area to nest and more likely to immigrate to the upwind area than vice-versa. This asymmetry in emigration rates is believed to be due to differing vegetation densities and has implications for vegetation management in relation to tropicbird nest success and population size.

Growth and Survival of Catfish ( Clarias anguillaris ) Juveniles Fed ...

African Journals Online (AJOL)

Juveniles of catfish, Clarias anguillaris (mean weight, 119.8g) were fed unconventional diets for ten weeks in outdoor hapas (net cages, 1m3 dimension) and the growth responses and feed utilization by the juveniles were compared. The experimental diets were (i) live maggots, (ii) live tilapia fry, (iii) commercial catfish feed ...

Functional Annotation of All Salmonid Genomes (FAASG): an international initiative supporting future salmonid research, conservation and aquaculture.

Science.gov (United States)

Macqueen, Daniel J; Primmer, Craig R; Houston, Ross D; Nowak, Barbara F; Bernatchez, Louis; Bergseth, Steinar; Davidson, William S; Gallardo-Escárate, Cristian; Goldammer, Tom; Guiguen, Yann; Iturra, Patricia; Kijas, James W; Koop, Ben F; Lien, Sigbjørn; Maass, Alejandro; Martin, Samuel A M; McGinnity, Philip; Montecino, Martin; Naish, Kerry A; Nichols, Krista M; Ólafsson, Kristinn; Omholt, Stig W; Palti, Yniv; Plastow, Graham S; Rexroad, Caird E; Rise, Matthew L; Ritchie, Rachael J; Sandve, Simen R; Schulte, Patricia M; Tello, Alfredo; Vidal, Rodrigo; Vik, Jon Olav; Wargelius, Anna; Yáñez, José Manuel

2017-06-27

We describe an emerging initiative - the 'Functional Annotation of All Salmonid Genomes' (FAASG), which will leverage the extensive trait diversity that has evolved since a whole genome duplication event in the salmonid ancestor, to develop an integrative understanding of the functional genomic basis of phenotypic variation. The outcomes of FAASG will have diverse applications, ranging from improved understanding of genome evolution, to improving the efficiency and sustainability of aquaculture production, supporting the future of fundamental and applied research in an iconic fish lineage of major societal importance.

Influences of Stocking Salmon Carcass Analogs on Salmonids in Klickitat River Tributaries, 2001-2005 Completion Report.

Energy Technology Data Exchange (ETDEWEB)

Zendt, Joe; Sharp, Bill (Yakama Nation Fisheries, Toppenish, WA)

2006-09-01

This report describes the work completed by the Yakama Nation Fisheries Program (YNFP) in the Klickitat subbasin in south-central Washington under BPA innovative project No.200105500--Influences of stocking salmon carcass analogs on salmonids in Columbia River Tributaries. Salmon carcasses historically provided a significant source of marine-derived nutrients to many stream systems in the Columbia basin, and decreased run sizes have led to a loss of this nutrient source in many streams. Partners in this project developed a pathogen-free carcass analog and stocked the analogs in streams with the following objectives: restoring food availability to streams with reduced anadromous salmon returns; mimicking the natural pathways and timing of food acquisition by salmonids; minimizing unintended negative ecological effects; and increasing the growth and survival of salmonids. In the Klickitat subbasin, carcass analogs were stocked in two streams in 2002 and 2003; a third stream was used as a control. Salmonid fish abundance, growth, and stomach contents were monitored in all three streams before and after carcass analog placement. Fish, invertebrate, and periphyton samples were also collected for stable isotope analysis (to determine if nutrients from carcass analogs were incorporated into the stream food web). Water quality samples were also collected to determine if nutrient overloading occurred in streams. Significant differences in growth were found between fish in treated and untreated stream reaches. Fish in treatment reaches exhibited higher instantaneous growth rates approximately one month after the first carcass analog stocking. Stomach contents sampling indicated that salmonid fish routinely consumed the carcass analog material directly, and that stomach fullness of fish in treatment reaches was higher than in untreated reaches in the first few weeks following carcass analog stockings. No significant differences were detected in fish abundance between

Fish Individual-based Numerical Simulator (FINS): A particle-based model of juvenile salmonid movement and dissolved gas exposure history in the Columbia River Basin

International Nuclear Information System (INIS)

Scheibe, Timothy D.; Richmond, Marshall C.

2002-01-01

This paper describes a numerical model of juvenile salmonid migration in the Columbia and Snake Rivers. The model, called the Fish Individual-based Numerical Simulator or FINS, employs a discrete, particle-based approach to simulate the migration and history of exposure to dissolved gases of individual fish. FINS is linked to a two-dimensional (vertically-averaged) hydrodynamic simulator that quantifies local water velocity, temperature, and dissolved gas levels as a function of river flow rates and dam operations. Simulated gas exposure histories can be input to biological mortality models to predict the effects of various river configurations on fish injury and mortality due to dissolved gas supersaturation. Therefore, FINS serves as a critical linkage between hydrodynamic models of the river system and models of biological impacts. FINS was parameterized and validated based on observations of individual fish movements collected using radiotelemetry methods during 1997 and 1998 . A quasi-inverse approach was used to decouple fish swimming movements from advection with the local water velocity, allowing inference of time series of non-advective displacements of individual fish from the radiotelemetry data. Statistical analyses of these displacements are presented, and confirm that strong temporal correlation of fish swimming behavior persists in some cases over several hours. A correlated random-walk model was employed to simulate the observed migration behavior, and parameters of the model were estimated that lead to close correspondence between predictions and observations

The Influence of Tag Presence on the Mortality of Juvenile Chinook Salmon Exposed to Simulated Hydroturbine Passage: Implications for Survival Estimates and Management of Hydroelectric Facilities

Energy Technology Data Exchange (ETDEWEB)

Carlson, Thomas J.; Brown, Richard S.; Stephenson, John R.; Pflugrath, Brett D.; Colotelo, Alison HA; Gingerich, Andrew J.; Benjamin, Piper L.; Langeslay, Mike; Ahmann, Martin L.; Johnson, Robert L.; Skalski, John R.; Seaburg, Adam; Townsend, Richard L.

2012-05-01

Each year, millions of fish have telemetry tags (acoustic, radio, inductive) surgically implanted to assess their passage and survival through hydropower facilities. One route of passage of particular concern is through hydro turbines, in which fish may be exposed to a range of potential injuries, including barotraumas from rapid decompression. The change in pressure from acclimation to exposure (nadir) has been found to be an important factor in predicting the likelihood of mortality and injury for juvenile Chinook salmon undergoing rapid decompression associated with simulated turbine passage. The presence of telemetry tags has also been shown to influence the likelihood of injury and mortality for juvenile Chinook salmon. This research investigated the likelihood of mortality and injury for juvenile Chinook salmon carrying telemetry tags and exposed to a range of simulated turbine passage. Several factors were examined as predictors of mortal injury for fish undergoing rapid decompression, and the ratio of pressure change and tag burden were determined to be the most predictive factors. As the ratio of pressure change and tag burden increase, the likelihood of mortal injury also increases. The results of this study suggest that previous survival estimates of juvenile Chinook salmon passing through hydro turbines may have been biased due to the presence of telemetry tags, and this has direct implications to the management of hydroelectric facilities. Realistic examples indicate how the bias in turbine passage survival estimates could be 20% or higher, depending on the mass of the implanted tags and the ratio of acclimation to exposure pressures. Bias would increase as the tag burden and pressure ratio increase, and have direct implications on survival estimates. It is recommended that future survival studies use the smallest telemetry tags possible to minimize the potential bias that may be associated with carrying the tag.

Development of a systemwide predator control program: Stepwise implementation of a predator index, predator control fisheries, and evaluation plan in the Columbia River basin (Northern Squawfish Management Program). Section 1: Implementation; Annual report 1995

International Nuclear Information System (INIS)

Young, F.R.

1997-04-01

The authors report their results from the fifth year of a basinwide program to harvest northern squawfish (Ptychocheilus oregonensis) in an effort to reduce mortality due to northern squawfish predation on juvenile salmonids during their emigration from natal streams to the ocean. Earlier work in the Columbia River Basin suggested predation by northern squawfish on juvenile salmonids may account for most of the 10--20% mortality juvenile salmonids experience in each of eight Columbia and Snake River reservoirs. Modeling simulations based on work in John Day Reservoir from 1982 through 1988 indicated that if predator-sized northern squawfish were exploited at a 10--20% rate, the resulting restructuring of their population could reduce their predation on juvenile salmonids by 50%

A salmonid EST genomic study: genes, duplications, phylogeny and microarrays

Directory of Open Access Journals (Sweden)

Brahmbhatt Sonal

2008-11-01

Full Text Available Abstract Background Salmonids are of interest because of their relatively recent genome duplication, and their extensive use in wild fisheries and aquaculture. A comprehensive gene list and a comparison of genes in some of the different species provide valuable genomic information for one of the most widely studied groups of fish. Results 298,304 expressed sequence tags (ESTs from Atlantic salmon (69% of the total, 11,664 chinook, 10,813 sockeye, 10,051 brook trout, 10,975 grayling, 8,630 lake whitefish, and 3,624 northern pike ESTs were obtained in this study and have been deposited into the public databases. Contigs were built and putative full-length Atlantic salmon clones have been identified. A database containing ESTs, assemblies, consensus sequences, open reading frames, gene predictions and putative annotation is available. The overall similarity between Atlantic salmon ESTs and those of rainbow trout, chinook, sockeye, brook trout, grayling, lake whitefish, northern pike and rainbow smelt is 93.4, 94.2, 94.6, 94.4, 92.5, 91.7, 89.6, and 86.2% respectively. An analysis of 78 transcript sets show Salmo as a sister group to Oncorhynchus and Salvelinus within Salmoninae, and Thymallinae as a sister group to Salmoninae and Coregoninae within Salmonidae. Extensive gene duplication is consistent with a genome duplication in the common ancestor of salmonids. Using all of the available EST data, a new expanded salmonid cDNA microarray of 32,000 features was created. Cross-species hybridizations to this cDNA microarray indicate that this resource will be useful for studies of all 68 salmonid species. Conclusion An extensive collection and analysis of salmonid RNA putative transcripts indicate that Pacific salmon, Atlantic salmon and charr are 94–96% similar while the more distant whitefish, grayling, pike and smelt are 93, 92, 89 and 86% similar to salmon. The salmonid transcriptome reveals a complex history of gene duplication that is

Radio telemetry data - Characterizing migration and survival for juvenile Snake River sockeye salmon between the upper Salmon River basin and Lower Granite Dam

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This project estimates survival and characterizes the migration of juvenile sockeye salmon between the upper Salmon River basin in central Idaho and Lower Granite...

Potential effects of climate change on streambed scour and risks to salmonid survival in snow-dominated mountain basins

Science.gov (United States)

Jaime R. Goode; John M. Buffington; Daniele Tonina; Daniel J. Isaak; Russell F. Thurow; Seth Wenger; David Nagel; Charlie Luce; Doerthe Tetzlaff; Chris Soulsby

2013-01-01

Snowmelt-dominated basins in northern latitudes provide critical habitat for salmonids. As such, these systems may be especially vulnerable to climate change because of potential shifts in the frequency, magnitude, and timing of flows that can scour incubating embryos. A general framework is presented to examine this issue, using a series of physical models that link...

A Comparison of Growth and Survival of Aquacultured Juvenile Florida Pompano fed Fishmeal and Plant-Based Diets

Science.gov (United States)

Budden, D.

2016-02-01

We investigated the growth and survival of aquacultured juvenile Florida Pompano (Trachinotus carolinus) fed two different diets. Pompano (initial weight 7.7 g /fish) were randomly assigned to one of two dietary treatments: Zeigler pellets (fishmeal; 35% protein, 5% lipid) and a plant-based Repashy Soilent Green algae gel (plant-based; 35% protein, 6% lipid). Fish were fed rations of 5% body weight twice daily for eight weeks. Despite nearly equivalent proximate compositions for the two feeds, survival rates were significantly affected by diet. All fish fed the Zeigler diet survived; however, mortality was observed in 92% of the fish fed the Repashy diet. At the end of the trial, mean weight gain of surviving pompano was highest in fish fed Zeigler pellets. Mean specific growth rate (SGR) for fish fed the Zeigler diet (0.24% per day) was higher than for fish fed Repashy (-2.44%).While plant-based feeds have been successfully used with the species, these results suggest that the plant-based Repashy diet is not suitable for survival or growth of aquacultured Florida pompano.

Effects of temperature and salinity on survival, growth and DNA methylation of juvenile Pacific abalone, Haliotis discus hannai Ino

Science.gov (United States)

Kong, Ning; Liu, Xiao; Li, Junyuan; Mu, Wendan; Lian, Jianwu; Xue, Yanjie; Li, Qi

2017-09-01

Temperature and salinity are two of the most potent abiotic factors influencing marine mollusks. In this study, we investigated the individual and combined effects of temperature and salinity on the survival and growth of juvenile Pacific abalone, Haliotis discus hannai Ino, and also examined the DNA methylation alteration that may underpin the phenotypic variation of abalone exposed to different rearing conditions. The single-factor data showed that the suitable ranges of temperature and salinity were 16-28°C at a constant salinity of 32, and 24-40 at a constant temperature of 20°C, respectively. The two-factor data indicated that both survival and growth were significantly affected by temperature, salinity and their interaction. The optimal temperature-salinity combination for juveniles was 23-25°C and 30-36. To explore environment-induced DNA methylation alteration, the methylation-sensitive amplified polymorphism (MSAP) technique was used to analyze the genomic methylation profiles of abalone reared in optimal and adverse conditions. Neither temperature nor salinity induced evident changes in the global methylation level, but 67 and 63 differentially methylated loci were identified in temperature and salinity treatments, respectively. The between-group eigen analysis also showed that both temperature and salinity could induce epigenetic differentiation in H. discus hannai Ino. The results of our study provide optimal rearing conditions for juvenile H. discus hannai Ino, and represent the first step toward revealing the epigenetic regulatory mechanism of abalone in response to thermal and salt stresses.

Lower Columbia River and Estuary Habitat Monitoring Study, 2011 - Final Report

Energy Technology Data Exchange (ETDEWEB)

Borde, Amy B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kaufmann, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cullinan, Valerie I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zimmerman, Shon A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thom, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wright, Cynthia L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2012-03-01

The Ecosystem Monitoring Program is a collaborative effort between the Lower Columbia River Estuary Partnership (LCREP), University of Washington, Wetland Ecosystem Team (UW), US Geological Survey, Water Science Center (USGS), National Oceanic and Atmospheric Administration, National Marine Fisheries Service (NOAA-Fisheries, hereafter NOAA), and Pacific Northwest National Laboratory, Marine Sciences Laboratory (PNNL). The goal of the program is to conduct emergent wetland monitoring aimed at characterizing salmonid habitats in the lower Columbia River and estuary (LCRE) from the mouth of the estuary to Bonneville Dam (Figure 1). This is an ecosystem based monitoring program focused on evaluating status and trends in habitat and reducing uncertainties regarding these ecosystems to ultimately improve the survival of juvenile salmonids through the LCRE. This project comprehensively assesses habitat, fish, food web, and abiotic conditions in the lower river, focusing on shallow water and vegetated habitats used by juvenile salmonids for feeding, rearing and refugia. The information is intended to be used to guide management actions associated with species recovery, particularly that of threatened and endangered salmonids. PNNL’s role in this multi-year study is to monitor the habitat structure (e.g., vegetation, topography, channel morphology, and sediment type) as well as hydrologic patterns.

EFFECT OF NON-ESSENTIAL ELEMENTS (MERCURY. ARSENIC ON SALMONIDS (SALMONIDAE (REVIEW

Directory of Open Access Journals (Sweden)

І. Hrytsyniak

2015-09-01

Full Text Available Purpose. The problem of water ecosystem pollution with heavy metals achieved great actuality during recent years, both because of their significant distribution in environment, and wide spectrum of their toxic effects on fish organism. Much attention in modern scientific literature is given to the problem of the effects of heavy metals, including mercury and arsenic, on fish organism. However, investigations in this field are conducted mainly on cyprinids, while physiological and biochemical mechanisms of the effects of heavy metals on salmonids are less studied. According to this, the studies of the sources of heavy metals in water ecosystems, peculiarities of their action in salmonid organism on subcellular, cellular, tissue and organ levels, species and age-related peculiarities of the effects of heavy metals are of great scientific and practical importance. The purpose of this work is to review the mentioned problems. Findings. The work characterizes the effects of mercury and arsenic on salmonids on subcellular, cellular, tissue and organ levels. The article contains characteristic of conditions, under which toxic or lethal action of the mentioned xenobiotics on different species of salmonids was observed. Originality. The paper summarizes literature data concerning the effect of mercury and arsenic on salmonids. Attention is accented on the sources of the mentioned pollutants in surface waters, physiological and biochemical mechanisms of their effects on salmonids, and on factors, which determine the level of their toxicity. Lethal concentrations of mercury and arsenic to salmonids, depending on experiment duration, species and age-related peculiarities are presented. Practical value. Data presented in the review can be used for the explanation of physiological and biochemical mechanisms of the adaptation of salmonids to surface water pollution with heavy metals, diagnostics of fish pathologies caused by toxic effects of mercury and

Survival of juvenile chinook salmon and coho salmon in the Roza Dam fish bypass and in downstream reaches of the Yakima River, Washington, 2016

Science.gov (United States)

Kock, Tobias J.; Perry, Russell W.; Hansen, Amy C.

2016-12-22

Estimates of juvenile salmon survival are important data for fishery managers in the Yakima River Basin. Radiotelemetry studies during 2012–14 showed that tagged juvenile Chinook salmon (Oncorhynchus tshawytscha) that passed through the fish bypass at Roza Dam had lower survival than fish that passed through other routes at the dam. That study also identified flow-survival relationships in the reaches between the Roza Dam tailrace and Sunnyside Dam. During 2012–14, survival also was estimated through reaches downstream of Sunnyside Dam, but generally, sample sizes were low and the estimates were imprecise. In 2016, we conducted an evaluation using acoustic cameras and acoustic telemetry to build on information collected during the previous study. The goal of the 2016 research was to identify areas where mortality occurs in the fish bypass at Roza Dam, and to estimate reach-specific survival in reaches downstream of the dam. The 2016 study included juvenile Chinook salmon and coho salmon (O. kisutch).Three acoustic cameras were used to observe fish behavior (1) near the entrances to the fish bypass, (2) at a midway point in the fish bypass (convergence vault), and (3) at the bypass outfall. In total, 504 hours of acoustic camera footage was collected at these locations. We determined that smolt-sized fish (95–170 millimeters [mm]) were present in the highest proportions at each location, but predator-sized fish (greater than 250 mm) also were present at each site. Fish presence generally peaked during nighttime hours and crepuscular periods, and was low during daytime hours. In the convergence vault, smolt-sized fish exhibited holding behavior patterns, which may explain why some fish delayed while passing through the bypass.Some of the acoustic-tagged fish were delayed in the fish bypass following release, but there was no evidence to suggest that they experienced higher mortality than fish that were released at the bypass outfall or downstream of the dam

Effect of Migration Pathway on Travel Time and Survival of Acoustic-Tagged Juvenile Salmonids in the Columbia River Estuary

Energy Technology Data Exchange (ETDEWEB)

Harnish, Ryan A.; Johnson, Gary E.; McMichael, Geoffrey A.; Hughes, Michael S.; Ebberts, Blaine D.

2012-02-01

Off-channel areas (side channels, tidal flats, sand bars, and shallow-water bays) may serve as important migration corridors through estuarine environments for salmon and steelhead smolts. Relatively large percentages (21-33%) of acoustic-tagged yearling and subyearling Chinook salmon and steelhead smolts were detected migrating through off-channel areas of the Columbia River estuary in 2008. The probability of survival for off-channel migrants (0.78-0.94) was similar to or greater than the survival probability of main channel migrants (0.67-0.93). Median travel times were similar for all species or run types and migration pathways we examined, ranging from 1-2 d. The route used by smolts to migrate through the estuary may affect their vulnerability to predation. Acoustic-tagged steelhead that migrated nearest to avian predator nesting colonies experienced higher predation rates (24%) than those that migrated farthest from the colonies (10%). The use of multiple migration pathways may be advantageous to out-migrating smolts because it helps to buffer against high rates of mortality, which may occur in localized areas, and helps to minimize inter- and intraspecific competition.

Effects of food type, feeding frequency, and temperature on juvenile survival and growth of Marisa cornuarietis (Mollusca: Gastropoda).

Science.gov (United States)

Selck, Henriette; Aufderheide, John; Pounds, Nadine; Staples, Charles; Caspers, Norbert; Forbes, Valery

2006-06-01

The present experiments are part of a larger study designed to investigate the influence of husbandry parameters on the life history of the ramshorn snail, Marisa cornuarietis, in order to identify suitable husbandry conditions for maintaining multi-generation populations in the laboratory for use in ecotoxicological testing. In this paper we focus on the effects of a combination of food types and feeding frequencies (i.e., the frequency with which the snails were offered food) on juvenile growth and survival at different temperatures. Offspring produced in the laboratory by wild specimens of M. cornuarietis, from Puerto Rico, were used to test the effects of three types of food (lettuce, alginate with fish food, alginate with snail mix) fed at three frequencies (given ad libitum on 4/4, 2/4, or 1/4 d) on juvenile survival and growth. The 4-d feeding regimens were repeated four times, giving a total of 16 d for the experiments. The experiments were conducted at two temperatures (22 degrees and 25 degrees C) under a 12 h light:12 h dark photoperiod. Juvenile growth rates increased with increasing feeding frequency for all food types. The most rapid growth rates occurred in the high-frequency lettuce treatments and the slowest growth rates in the low-frequency lettuce and alginate with snail mix treatments. Juvenile snails grew faster at 25 degrees than at 22 degrees C, and mortality was about twice as high at the lower temperature. Growth rates were used to provide a rough estimate of time to maturity, which was determined to take about twice as long at 22 degrees than at 25 degrees C. The results showed that lettuce is the best food if supplied in abundance, but effects on growth are very dependent on feeding frequency and temperature. We conclude that 25 degrees C is a more appropriate temperature for maintaining populations than 22 degrees C, that lettuce provides a suitable food source, and that food should be supplied continuously for husbandry and toxicity

Performance of a surface bypass structure to enhance juvenile steelhead passage and survival at Lower Granite Dam, Washington

Science.gov (United States)

Adams, Noah S.; Plumb, John M.; Perry, Russell W.; Rondorf, Dennis W.

2014-01-01

An integral part of efforts to recover stocks of Pacific salmon Oncorhynchus spp. and steelhead O. mykiss in Pacific Northwest rivers is to increase passage efficacy and survival of juveniles past hydroelectric dams. As part of this effort, we evaluated the efficacy of a prototype surface bypass structure, the removable spillway weir (RSW), installed in a spillbay at Lower Granite Dam, Washington, on the Snake River during 2002, 2003, 2005, and 2006. Radio-tagged juvenile steelhead were released upstream from the dam and their route of passage through the turbines, juvenile bypass, spillway, or RSW was recorded. The RSW was operated in an on-or-off condition and passed 3–13% of the total discharge at the dam when it was on. Poisson rate models were fit to the passage counts of hatchery- and natural-origin juvenile steelhead to predict the probability of fish passing the dam. Main-effect predictor variables were RSW operation, diel period, day of the year, proportion of flow passed by the spillway, and total discharge at the dam. The combined fish passage through the RSW and spillway was 55–85% during the day and 37–61% during the night. The proportion of steelhead passing through nonturbine routes was 95% when the RSW was on during the day. The ratio of the proportion of steelhead passed to the proportion of water passing the RSW was from 6.3:1 to 10.0:1 during the day and from 2.7:1 to 5.2:1 during the night. Steelhead passing through the RSW exited the tailrace about 15 min faster than fish passing through the spillway. Mark–recapture single-release survival estimates for steelhead passing the RSW ranged from 0.95 to 1.00. The RSW appeared to be an effective bypass structure compared with other routes of fish passage at the dam.

Benefits of prescribed flows for salmon smolt survival enhancement vary longitudinally in a highly managed river system

Science.gov (United States)

Courter, Ian; Garrison, Thomas; Kock, Tobias J.; Perry, Russell W.; Child, David; Hubble, Joel

2016-01-01

The influence of streamflow on survival of emigrating juvenile Pacific salmonids Oncorhynchus spp. (smolts) is a major concern for water managers throughout the northeast Pacific Rim. However, few studies have quantified flow effects on smolt survival, and available information does not indicate a consistent flow–survival relationship within the typical range of flows under management control. In the Yakima Basin, Washington, the potential effects of streamflow alterations on smolt survival have been debated for over 20 years. Using a series of controlled flow releases from upper basin reservoirs and radiotelemetry, we quantified the relationship between flow and yearling Chinook salmon smolt survival in the 208 km reach between Roza Dam and the Yakima River mouth. A multistate mark–recapture model accounted for weekly variation in flow conditions experienced by tagged fish in four discrete river segments. Smolt survival was significantly associated with streamflow in the Roza Reach [river kilometre (rkm) 208–189] and marginally associated with streamflow in the Sunnyside Reach (rkm 169–77). However, smolt survival was not significantly associated with flow in the Naches and Prosser Reaches (rkm 189–169 and rkm 77–3). This discrepancy indicates potential differences in underlying flow-related survival mechanisms, such as predation or passage impediments. Our results clarify trade-offs between flow augmentation for fisheries enhancement and other beneficial uses, and our study design provides a framework for resolving uncertainties about streamflow effects on migratory fish survival in other river systems. 

Latent Toxicity of Endothall to Anadromous Salmonids During Seawater Challenge.

Science.gov (United States)

Courter, Lauren A; Garrison, Thomas M; Courter, Ian I

2016-05-01

Limited evidence exists on the latent effects of toxicant exposure on the seawater adaptability of anadromous salmon and steelhead. It is unclear whether such an effect exists for the widely used and relatively non-toxic herbicide endothall. Coho salmon, Oncorhynchus kisutch (coho), Chinook salmon, O. tshawytscha (Chinook), and anadromous rainbow trout, O. mykiss (steelhead) were subjected to a 10-day seawater challenge following freshwater treatments [0-12 mg acid equivalent (a.e)./L at 96 h]. Mean survival resulted in 82 % (n = 225), 84 % (n = 133), 90 % (n = 73) and 59 % (n = 147) survival for 0, 3-5, 6-8, and 9-12 mg a.e./L, respectively. Our results indicate a lower toxicity threshold compared with previously reported acute toxicity results, but higher compared with previous seawater challenge studies. We demonstrate the utility of the seawater challenge assay to accurately define toxic effects of pesticides on salmonids with complex life-histories.

Assessing fish predation on migrating juvenile steelhead and a retrospective comparison to steelhead survival through the Priest Rapids Hydroelectric Project, Columbia River, Washington, 2009-11

Science.gov (United States)

Hardiman, Jill M.; Counihan, Timothy D.; Burgess, Dave S.; Simmons, Katrina E.; Holmberg, Glen S.; Rogala, Josh; Polacek, Rochelle

2012-01-01

The U.S. Geological Survey (USGS) and the Washington Department of Fish and Wildlife (WDFW) have been working with the Public Utility District No. 2 of Grant County, Washington (Grant PUD), to increase their understanding of predator-prey interactions in the Priest Rapids Hydroelectric Project (PRP), Columbia River, Washington. For this study, the PRP is defined as the area approximately 6 kilometers upstream of Wanapum Dam to the Priest Rapids Dam tailrace, 397.1 miles from the mouth of the Columbia River. Past year’s low survival numbers of juvenile steelhead (Oncorhynchus mykiss) through Wanapum and Priest Rapids Dams has prompted Grant PUD, on behalf of the Priest Rapids Coordinating Committee, to focus research efforts on steelhead migration and potential causal mechanisms for low survival. Steelhead passage survival in 2009 was estimated at 0.944 through the Wanapum Development (dam and reservoir) and 0.881 through the Priest Rapids Development and for 2010, steelhead survival was 0.855 for Wanapum Development and 0.904 for Priest Rapids Development. The USGS and WDFW implemented field collection efforts in 2011 for northern pikeminnow (Ptychocheilus oregonensis), smallmouth bass (Micropterus dolomieu), and walleye (Sander vitreus, formerly Stizostedion vitreum) and their diets in the PRP. For predator indexing, we collected 948 northern pikeminnow, 237 smallmouth bass, 18 walleye, and two largemouth bass (Micropterus salmoides). The intent of this study was to provide standardized predation indices within individual reaches of the PRP to discern spatial variability in predation patterns. Furthermore, the results of the 2011 study were compared to results of a concurrent steelhead survival study. Our results do not indicate excessively high predation of Oncorhynchus spp. occurring by northern pikeminnow or smallmouth bass in any particular reach throughout the study area. Although we found Oncorhynchus spp. in the predator diets, the relative

Using cure models for analyzing the influence of pathogens on salmon survival

Science.gov (United States)

Ray, Adam R; Perry, Russell W.; Som, Nicholas A.; Bartholomew, Jerri L

2014-01-01

Parasites and pathogens influence the size and stability of wildlife populations, yet many population models ignore the population-level effects of pathogens. Standard survival analysis methods (e.g., accelerated failure time models) are used to assess how survival rates are influenced by disease. However, they assume that each individual is equally susceptible and will eventually experience the event of interest; this assumption is not typically satisfied with regard to pathogens of wildlife populations. In contrast, mixture cure models, which comprise logistic regression and survival analysis components, allow for different covariates to be entered into each part of the model and provide better predictions of survival when a fraction of the population is expected to survive a disease outbreak. We fitted mixture cure models to the host–pathogen dynamics of Chinook Salmon Oncorhynchus tshawytscha and Coho Salmon O. kisutch and the myxozoan parasite Ceratomyxa shasta. Total parasite concentration, water temperature, and discharge were used as covariates to predict the observed parasite-induced mortality in juvenile salmonids collected as part of a long-term monitoring program in the Klamath River, California. The mixture cure models predicted the observed total mortality well, but some of the variability in observed mortality rates was not captured by the models. Parasite concentration and water temperature were positively associated with total mortality and the mortality rate of both Chinook Salmon and Coho Salmon. Discharge was positively associated with total mortality for both species but only affected the mortality rate for Coho Salmon. The mixture cure models provide insights into how daily survival rates change over time in Chinook Salmon and Coho Salmon after they become infected with C. shasta.

Comparing stream-specific to generalized temperature models to guide salmonid management in a changing climate

Science.gov (United States)

Andrew K. Carlson,; William W. Taylor,; Hartikainen, Kelsey M.; Dana M. Infante,; Beard, Douglas; Lynch, Abigail

2017-01-01

Global climate change is predicted to increase air and stream temperatures and alter thermal habitat suitability for growth and survival of coldwater fishes, including brook charr (Salvelinus fontinalis), brown trout (Salmo trutta), and rainbow trout (Oncorhynchus mykiss). In a changing climate, accurate stream temperature modeling is increasingly important for sustainable salmonid management throughout the world. However, finite resource availability (e.g. funding, personnel) drives a tradeoff between thermal model accuracy and efficiency (i.e. cost-effective applicability at management-relevant spatial extents). Using different projected climate change scenarios, we compared the accuracy and efficiency of stream-specific and generalized (i.e. region-specific) temperature models for coldwater salmonids within and outside the State of Michigan, USA, a region with long-term stream temperature data and productive coldwater fisheries. Projected stream temperature warming between 2016 and 2056 ranged from 0.1 to 3.8 °C in groundwater-dominated streams and 0.2–6.8 °C in surface-runoff dominated systems in the State of Michigan. Despite their generally lower accuracy in predicting exact stream temperatures, generalized models accurately projected salmonid thermal habitat suitability in 82% of groundwater-dominated streams, including those with brook charr (80% accuracy), brown trout (89% accuracy), and rainbow trout (75% accuracy). In contrast, generalized models predicted thermal habitat suitability in runoff-dominated streams with much lower accuracy (54%). These results suggest that, amidst climate change and constraints in resource availability, generalized models are appropriate to forecast thermal conditions in groundwater-dominated streams within and outside Michigan and inform regional-level salmonid management strategies that are practical for coldwater fisheries managers, policy makers, and the public. We recommend fisheries professionals reserve resource

Columbia River System Operation Review : Final Environmental Impact Statement, Appendix C: Anadromous Fish and Juvenile Fish Transportation.

Energy Technology Data Exchange (ETDEWEB)

Columbia River System Operation Review (U.S.)

1995-11-01

This Appendix C of the Final Environmental Impact Statement for the Columbia River System discusses impacts on andromous fish and juvenile fish transportation. The principal andromous fish in the Columbia basin include salmonid species (Chinook, coho, and sockeye salmon, and steelhead) and nonsalmoinid andromous species (sturgeon, lamprey, and shad). Major sections in this document include the following: background, scope and process; affected environment for salmon and steelhead, shaded, lamprey, sturgeon; study methods; description of alternatives: qualitative and quantitative findings.

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

Influences of forest and rangeland management on salmonid fishes and their habitats

National Research Council Canada - National Science Library

Meehan, William R

1991-01-01

Contents : Stream ecosystems - Salmonid distributions and life histories - Habitat requirements of salmonids in streams - Natural processes - Timber harvesting, silvicultrue and watershed processes - Forest...

Monitoring of Juvenile Yearling Chinook Salmon and Steelhead Survival and Passage at Bonneville Dam, Spring 2010

Energy Technology Data Exchange (ETDEWEB)

Ploskey, Gene R.; Faber, Derrek M.; Weiland, Mark A.; Carlson, Thomas J.

2012-09-01

The purpose of this study was to estimate the survival for yearling Chinook salmon and steelhead smolts during spring 2010 in a portion of the Columbia River that includes Bonneville Dam. The study estimated smolt survival from a virtual release at Bonneville Dam to a survival array 81 km downstream of Bonneville Dam. We also estimated median forebay residence time, median tailrace egress time, and spill passage efficiency (SPE), as required in the Columbia Basin Fish Accords. A single release design was used to estimate survival from Bonneville Dam to a primary array located 81 km downstream of Bonneville. The approach did not include a reference tailrace release. Releases of acoustic-tagged smolts above John Day Dam to Hood River contributed to the formation of virtual releases at a Bonneville Dam forebay entrance array and at the face of the dam. A total of 3,880 yearling Chinook salmon and 3,885 steelhead smolts were tagged and released in the investigation. The Juvenile Salmon Acoustic Telemetry System (JSATS) tag model number ATS-156dB, weighing 0.438 g in air, was used in this investigation.

Survival and growth responses of snakehead fish Channa striata Bloch. juvenile in aerated and unaerated acid sulfate water

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, Purnamawati

2017-07-01

Full Text Available ABSTRACT  The aim of the research was to analyze survival rate, specific growth rate, albumin, and feed efficiency and physiological (blood glucose, cortisol, dan haemoglobin responses of snake head fish juvenil that reared at aerated and unaerated of tidal land water have been conducted in the laboratory. Experiments using completely randomized design with aerated and unaerated as a treatment, and each treatment has twelve replications. The snakehead fish juvenil wich length 2.4±0.2 cm and weight of 0.21±0.05 g reared in the aquarium that are size 30×25×35 cm (water volume 25 L with a stocking density 2 juvenile/L, for 40 days. The fishes were fed with commercial feed with protein content about 40%, feeding two times a day (morning and afternoon were at satiation. Replacement of water done every two days about 10% of the total water volume in the aquarium. The results showed that unaerated median significantly affected to biometric and physiological response of juvenile of snake head fish. The media un-aerated gives the best results shown by the higher value of survival (92%, specific growth rate (6.73%/ day, feed efficiency (78.22%, protein retention (41.91%, energy retention (30.81% value of albumin (6.60 g/100 mL and the haemoglobin (5.58 g/dL, and have the lowest value of cortisol (21.49 ng/L and blood glucose (43.36 mg/100 mL. Keywords: acid sulfate water, growth rate, aeration, Channa striata   ABSTRAK  Penelitian ini bertujuan untuk menganalisis respons kelangsungan hidup, pertumbuhan spesifik, albumin, dan efisiensi pakan dan fisiologis (kortisol, glukosa darah, dan hemoglobin juvenil ikan gabus yang dipelihara dengan dan tanpa aerasi pada media air rawa pasang surut. Penelitian menggunakan rancangan acak lengkap dengan aerasi dan tanpa aerasi sebagai perlakuan, dan masing-masing perlakuan memiliki 12 ulangan. Juvenil ikan gabus berukuran panjang 2,4±0,3 cm dan bobot 0,21±0,03 g dipelihara dalam akuarium 30×25×35 cm (volume

Effects of different protein and carbohydrate contents on growth and survival of juveniles of southern Chilean freshwater crayfish, Samastacus spinifrons

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Italo Salgado-Leu

2015-11-01

Full Text Available In cultivated aquatic organisms nutritional requirements are critical, not only for their impact on production techniques, but also, for their high incidence on production costs. There is limited knowledge on some species such as the southern Chilean freshwater crayfish, Samastacus spinifrons. In order to generate practical knowledge, a study was carried out to determine protein and carbohydrate content requirements. These factors were evaluated upon their effects on growth and survival of juveniles. For this purpose, individual weight, biomass gain, survival, and feed conversion parameters were measured. The assay was carried out in 42 days, it was conducted in a flow through system, using 21 plastic tanks of 10.6 L capacity. Each tank was seeded with 20 juveniles weighing 50 mg average each. A 3×2 factorial design was proposed with three protein contents (20, 30, 40% and two carbohydrate contents (low: from 16.3 to 23.5% and high: from 34.6 to 35.8%. Six treatments and three replicates were performed. Individuals were fed on apparent satiation once a day. The diets formulated with 30% of protein and the two carbohydrate contents resulted in higher biomass increases, food conversion efficiencies over 26%, and specific growth rate of 0.78%, all displaying significant differences. Survival showed highly significant differences; in all diets were superior to 60%, however the diets with 30% of protein surpassed 90%.

Fledgling survival increases with development time and adult survival across north and south temperate zones

Science.gov (United States)

Lloyd, Penn; Martin, Thomas E.

2016-01-01

Slow life histories are characterized by high adult survival and few offspring, which are thought to allow increased investment per offspring to increase juvenile survival. Consistent with this pattern, south temperate zone birds are commonly longer-lived and have fewer young than north temperate zone species. However, comparative analyses of juvenile survival, including during the first few weeks of the post-fledging period when most juvenile mortality occurs, are largely lacking. We combined our measurements of fledgling survival for eight passerines in South Africa with estimates from published studies of 57 north and south temperate zone songbird species to test three predictions: (1) fledgling survival increases with length of development time in the nest; (2) fledgling survival increases with adult survival and reduced brood size controlled for development time; and (3) south temperate zone species, with their higher adult survival and smaller brood sizes, exhibit higher fledgling survival than north temperate zone species controlled for development time. We found that fledgling survival was higher among south temperate zone species and generally increased with development time and adult survival within and between latitudinal regions. Clutch size did not explain additional variation, but was confounded with adult survival. Given the importance of age-specific mortality to life history evolution, understanding the causes of these geographical patterns of mortality is important.

Linking Forests and Fish: The Relationship Between Productivities of Salmonids and Forest Stands in Northern California

Science.gov (United States)

Wilzbach, P.; Frazey, S.

2005-05-01

Productivities of resident salmonid populations, upland, and riparian areas in 25 small watersheds of coastal northern California were estimated and compared to determine if: 1) upland site productivity predicted riparian site productivity; 2) either upland or riparian site productivity predicted salmonid productivity; and 3) other parameters explained more of the variance in salmonid productivity than upland or riparian site productivity. Salmonid productivity was indexed by total salmonid biomass, length of age 1 fish, and percent habitat saturation. Upland and riparian site productivities were estimated using site indices for redwood (Sequoia sempervirens) and red alder (Alnus rubra), respectively. Upland and riparian site indices were correlated, but neither factor contributed to the best approximating models of salmonid biomass or fish length at age one. Salmonid biomass was best described by a positive relationship with drainage area, and length at age was best described by a positive relationship with percent of riparian hardwoods. Percent habitat saturation was not well described by any of the models constructed. Lack of a relationship between upland conifer and salmonid productivity suggests that management of land for timber productivity and component streams for salmonid production in these sites will require separate, albeit integrated, strategies.

Variability in Migration Routes Influences Early Marine Survival of Juvenile Salmon Smolts.

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Nathan B Furey

Full Text Available Variability in animal migratory behavior is expected to influence fitness, but few empirical examples demonstrating this relationship exist. The initial marine phase in the migration of juvenile salmon smolts has been identified as a potentially critical life history stage to overall population productivity, yet how fine-scale migration routes may influence survival are unknown. Large-scale acoustic telemetry studies have estimated survival rates of outmigrant Pacific salmon smolts through the Strait of Georgia (SOG along the British Columbian coastline to the Pacific Ocean, but these data have not been used to identify and characterize fine-scale movements. Data collected on over 850 sockeye salmon (Oncorhynchus nerka and steelhead (Oncorhynchus mykiss smolts detected at an array in the Strait of Georgia in 2004-2008 and 2010-2013 were analyzed to characterize migration routes and link movements to subsequent survival at an array 250 km further along the marine migration pathway. Both species exhibited disproportionate use of the most eastern route in the Strait of Georgia (Malaspina Strait. While many smolts moved across the northern Strait of Georgia acoustic array with no indication of long-term milling or large-scale east-to-west movements, large proportions (20-40% of sockeye and 30-50% of steelhead exhibited a different behavior, apparently moving in a westward or counterclockwise pattern. Variability in migratory behavior for both species was linked to subsequent survival through the Strait of Georgia. Survival for both species was influenced by initial east-to-west location, and sockeye were further influenced by migration timing and duration of time spent near the northern Strait of Georgia array. Westward movements result in a net transport of smolts from Malaspina Strait to the Strait of Georgia, particularly for steelhead. Counterclockwise movements may be due to the currents in this area during the time of outmigration, and the

BIOCHEMICAL AND MORPHOMETRIC PARAMETERS OF PRE-LARVAE OF THREE SALMONIDS SPECIES AT ONE-DAY AGE

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Ye. Barylo

2016-06-01

Full Text Available Purpose. To study and analyze the morphometric and some biochemical parameters of pre-larval brown trout, rainbow trout and brook trout in post-embryonic period under the conditions of "Rybnyi Potik” farm in the Transcarpathian region for further use of the obtained data in scientific and practical works related to the cultivation of the juveniles of valuable salmonid species. Methodology. One-day free embryos (pre-larvae of brown trout, rainbow trout and brook trout we used as study materials. Morphometric parameters we studied by the methods of N. O. Lange, E. N. Dmitrieva. The content of total lipids was determined in accordance with Folch. in the tissuesm, which were taken for biochemical studies. Separate classes of lipids were received by thin layer chromatography. Findings. We carried out a comparative analysis of morphometric measurements and biochemical parameters of one-day pre-larval brown trout, rainbow trout and brook trout based on the obtained data. We investigated morphometric and biochemical specific features of pre-larvae in post-embryonic period and showed the species differences of morphometric measurements. Significant differences were observed between the content of lipids in the body and yolk sac of free embryos. In particular, a higher content of phospholipids and triglycerides was observed in the body of brook trout compared to brown trout. We also recorded higher contents of mono- and diacylglycerols, free cholesterol, non-etherified fatty acids (NEFA, triacylglycerols and cholesterol esters in the yolk sac of brook trout. Compared to brown trout, rainbow trout had a significant increase in mono- and diacylglycerols, free cholesterol and NEFA in both body and yolk sac as well higher levels of total lipids, triacylglycerols and cholesterol esters were registered in yolk sac. Originality. For the first time we carried out and compared the specific features of pre-larval brown trout, rainbow trout and brook trout in the

Elwha genetics - Elwha river salmonid genetics

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Elwha Dam is in the process of being removed, with fish restoration to occur in areas previously inaccessible to salmonids. Fish recovery anticipates that...

Ecology of Juvenile Salmon in Shallow Tidal Freshwater Habitats of the Lower Columbia River, 2007–2010

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Storch, Adam; Skalski, J. R.; Bryson, Amanda J.; Mallette, Christine; Borde, Amy B.; Van Dyke, E.; Sobocinski, Kathryn L.; Sather, Nichole K.; Teel, David; Dawley, Earl M.; Ploskey, Gene R.; Jones, Tucker A.; Zimmerman, Shon A.; Kuligowski, D. R.

2011-03-01

The TFM study was designed to investigate the ecology and early life history of juvenile salmonids within shallow (<5 m) tidal freshwater habitats of the LCRE. We started collecting field data in June 2007. Since then, monthly sampling has occurred in the vicinity of the Sandy River delta (rkm 192–208) and at other sites and times in lower river reaches of tidal freshwater (rkm 110 to 141). This report provides a comprehensive synthesis of data covering the field period from June 2007 through April 2010.

Assessment of Native Salmonids Above Hells Canyon Dam, Idaho; 1998 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Meyer, Kevin A. (Idaho Department of Fish and Game, Boise, ID)

1999-03-01

Native resident salmonids in the western United States are in decline throughout much of their range. The purpose of the multi-phased project is to restore native salmonids in the upper Snake River basin to self-sustaining, harvestable levels.

Effects of passive integrated transponder tags on survival and growth of juvenile Atlantic salmon Salmo salar

DEFF Research Database (Denmark)

Larsen, Martin Hage; Thorn, Aske N.; Skov, Christian

2013-01-01

Background: A laboratory experiment was conducted to assess the potential impacts of surgically implanted 23 and 32 mm passive integrated transponder (PIT) tags on survival, growth, and body condition of juvenile Atlantic salmon Salmo salar. Rate of tag retention and healing of the tagging incision...... were also evaluated. Atlantic salmon of three different size classes (I: 80 to 99 mm fork length (FL), II: 100 to 119 mm FL, III: 120 to 135 mm FL) were allocated to each of five experimental treatment groups: control, sham-operated (surgery without PIT-tag implantation), 23 mm PIT-tag implantation...... with and without suture closure of the incision, and 32 mm PIT-tag implantation without suture closure. Results: Over the 35-day experiment, mortality occurred only among fish tagged with 32 mm PIT tags (14%) and all fish larger than 103 mm FL survived. Non-sutured Atlantic salmon between 80 and 99 mm FL implanted...

75 FR 76400 - Endangered and Threatened Species; Take of Anadromous Fish

Science.gov (United States)

2010-12-08

... issues permits based on findings that such permits: (1) Are applied for in good faith; (2) if granted and... the summer ecology of juvenile salmonids in streams of the Lagunitas Creek (Marin County) and... study on the ecology of juvenile salmonids in Tomales Bay, and Pescadero Lagoon and their overall...

Compliance Monitoring of Yearling and Subyearling Chinook Salmon and Juvenile Steelhead Survival and Passage at John Day Dam, 2012

Energy Technology Data Exchange (ETDEWEB)

Skalski, J. R.; Townsend, Richard L.; Seaburg, Adam; Weiland, Mark A.; Woodley, Christa M.; Hughes, James S.; Ploskey, Gene R.; Deng, Zhiqun; Carlson, Thomas J.

2013-05-01

The purpose of this compliance study was to estimate dam passage survival of yearling and subyearling Chinook salmon and steelhead smolts at John Day Dam during the spring and summer outmigrations in 2012. Under the 2008 Federal Columbia River Power System (FCRPS) Biological Opinion (BiOp), dam passage survival should be greater than or equal to 0.96 for spring migrants and greater than or equal to 0.93 for summer migrants, estimated with a standard error (SE) less than or equal to 0.015. The study also estimated smolt passage survival from the forebay 2 km upstream of the dam to the tailrace 3 km downstream of the dam, as well as the forebay residence time, tailrace egress time, spill passage efficiency (SPE), and fish passage efficiency (FPE), as required in the Columbia Basin Fish Accords (Fish Accords). A virtual/paired-release design was used to estimate dam passage survival at John Day Dam. The approach included releases of smolts, tagged with acoustic micro-transmitters, above John Day Dam that contributed to the formation of a virtual release at the face of John Day Dam. A survival estimate from this release was adjusted by a paired release below John Day Dam. A total of 3376 yearling Chinook salmon, 5726 subyearling Chinook salmon, and 3239 steelhead smolts were used in the virtual releases. Sample sizes for the below-dam paired releases (R2 and R3, respectively) were 997 and 995 for yearling Chinook salmon smolts, 986 and 983 for subyearling Chinook salmon smolts, and 1000 and 1000 for steelhead smolts. The Juvenile Salmon Acoustic Telemetry System (JSATS) tags were manufactured by Advanced Telemetry Systems. Model SS300 tags, weighing 0.304 g in air, were surgically implanted in yearling and subyearling Chinook salmon, and Model SS130 tag, weighing 0.438 g in air, were surgically implanted in juvenile steelhead for this investigation. The intent of the spring study was to estimate dam passage survival during both 30% and 40% spill conditions. The two

Evaluation of juvenile salmonid bypass facilities and passage at water diversions on the lower Umatilla River. Final report

International Nuclear Information System (INIS)

Cameron, W.A.; Knapp, S.M.; Carmichael, R.W.

1997-07-01

Outdated juvenile and adult fish passage facilities were recently reconstructed at the five major irrigation dams on the lower Umatilla River, Oregon to meet National marine Fisheries Service (NMFS) design standards. Changes in design at juvenile fish bypass facilities included reduced mesh size on the rotating drum screens, larger screening area, a more oblique orientation of the drum screens to canal flow, improved screen seals, replacement of bypass portals with vertical slot bypass channels, and increased bypass pipe diameters. Weir-and-pool adult fish ladders and jump pools were replaced with vertical-slot ladders. From 1991--1995, they investigated injury and travel rate of juvenile fish moving through the facilities, and efficiency of screens in preventing fish entry into the canals. Water velocities in front of canal screens, at bypass channel entrances, and at ladder diffusers were measured to assess adherence to NMFS criteria and identify hydraulic patterns. Biological evaluations were conducted by releasing and recapturing marked yearling summer steelhead (Oncorhynchus mykiss), yearling spring chinook salmon (O. tshawytscha), and subyearling fall chinook salmon (O. tshawytscha) in varying locations within the fish passage facilities

The effects of intermittent exposure to low-pH and low-oxygen conditions on survival and growth of juvenile red abalone

Science.gov (United States)

Kim, T. W.; Barry, J. P.; Micheli, F.

2013-11-01

Exposure of nearshore animals to hypoxic, low-pH waters upwelled from below the continental shelf and advected near the coast may be stressful to marine organisms and lead to impaired physiological performance. We mimicked upwelling conditions in the laboratory and tested the effect of fluctuating exposure to water with low-pH and/or low-oxygen levels on the mortality and growth of juvenile red abalone (Haliotis rufescens, shell length 5-10 mm). Mortality rates of juvenile abalone exposed to low-pH (7.5, total scale) and low-O2 (40% saturation, mg L-1) conditions for periods of 3 to 6 h every 3-5 days over 2 weeks did not differ from those exposed to control conditions (O2: 100% saturation, 12 mg L-1; pH 8.0). However, when exposure was extended to 24 h, twice over a 15-day period, juveniles experienced 5-20% higher mortality in the low-oxygen treatments compared to control conditions. Growth rates were reduced significantly when juveniles were exposed to low-oxygen and low-pH treatments. Furthermore, individual variation of growth rate increased when juveniles were exposed simultaneously to low-pH and low-O2 conditions. These results indicate that prolonged exposure to low-oxygen levels is detrimental for the survival of red abalone, whereas pH is a crucial factor for their growth. However, the high individual variation in growth rate under low levels of both pH and oxygen suggests that cryptic phenotypic plasticity may promote resistance to prolonged upwelling conditions by a portion of the population.

Conducta alimenticia, supervivencia y crecimiento de juveniles silvestres de Graus nigra Philippi, 1887 en cautiverio (Perciformes: Kyphosidae Feeding behavior, survival, and growth of wild Graus nigra Philippi, 1887 juveniles in captivity (Perciformes: Kyphosidae

Directory of Open Access Journals (Sweden)

Héctor Flores

2011-11-01

Full Text Available Se colectaron juveniles silvestres de Graus nigra, que fueron aclimatados durante 30 días en estanques con flujo de agua abierto y a temperatura ambiente, siendo alimentados con alimento formulado. Los peces fueron separados en seis grupos que se mantuvieron en experimentación por 196 días. La supervivencia promedio fue de 80%. El crecimiento en longitud total mostró un incremento promedio del 93,3% para los juveniles grandes (grupos 4, 5 y 6 y 125% para los pequeños (grupos 1, 2 y 3. El crecimiento en peso total mostró un incremento promedio de 434% para los peces grandes (grupos 4, 5 y 6 y de 707% para los pequeños (grupos 1, 2 y 3. Se concluyó que G. nigra toleró el cautiverio y el manejo, con una supervivencia relativamente alta, lo que hace de ella una especie atractiva para la acuicultura chilena.Wild juveniles of Graus nigra were collected and acclimated for 30 days in ponds with open-water flow and ambient temperature; the specimens were given a formulated feed. Fish individuals were separated into six groups that were studied for 196 days. The average survival was 80%. The total length increased an average of 93.3% for large individuals (groups 4, 5, 6 and 125% for small ones (groups 1, 2, 3. The total weight showed an average increase of 434% for large fishes (groups 4, 5, 6 and 707% for small ones (groups 1, 2, 3. Graus nigra was found to tolerate captivity and handling, with a relatively high survival rate, making it an attractive species for aquaculture in Chile.

Fitness Consequences of Boldness in Juvenile and Adult Largemouth Bass.

Science.gov (United States)

Ballew, Nicholas G; Mittelbach, Gary G; Scribner, Kim T

2017-04-01

To date, most studies investigating the relationship between personality traits and fitness have focused on a single measure of fitness (such as survival) at a specific life stage. However, many personality traits likely have multiple effects on fitness, potentially operating across different functional contexts and stages of development. Here, we address the fitness consequences of boldness, under seminatural conditions, across life stages and functional contexts in largemouth bass (Micropterus salmoides). Specifically, we report the effect of boldness on (1) juvenile survivorship in an outdoor pond containing natural prey and predators and (2) adult reproductive success in three outdoor ponds across three reproductive seasons (years). Juvenile survival was negatively affected by boldness, with bolder juveniles having a lower probability of survival than shyer juveniles. In contrast, bolder adult male bass had greater reproductive success than their shyer male counterparts. Female reproductive success was not affected by boldness. These findings demonstrate that boldness can affect fitness differently across life stages. Further, boldness was highly consistent across years and significantly heritable, which suggests that boldness has a genetic component. Thus, our results support theory suggesting that fitness trade-offs across life stages may contribute to the maintenance of personality variation within populations.

Assessment of native salmonids above Hells Canyon Dam, Idaho; 1998 annual progress report

International Nuclear Information System (INIS)

Meyer, Kevin A.

1999-01-01

Native resident salmonids in the western United States are in decline throughout much of their range. The purpose of the multi-phased project is to restore native salmonids in the upper Snake River basin to self-sustaining, harvestable levels

Persistence of Salmonid Redds

Science.gov (United States)

Buffington, J. M.; Buxton, T.; Fremier, A. K.; Hassan, M. A.; Yager, E.

2013-12-01

The construction of redds by spawning salmonids modifies fluvial processes in ways that are beneficial to egg and embryo survival. Redd topography induces hyporheic flow that oxygenates embryos incubating within the streambed and creates form drag that reduces bed mobility and scour of salmonid eggs. Winnowing of fine material during redd construction also coarsens the streambed, increasing bed porosity and hyporheic flow and reducing bed mobility. In addition to the biological benefits, redds may influence channel morphology by altering channel hydraulics and bed load transport rates depending on the size and extent of redds relative to the size of the channel. A key question is how long do the physical and biological effects of redds last? Field observations indicate that in some basins redds are ephemeral, with redd topography rapidly erased by subsequent floods, while in other basins, redds can persist for years. We hypothesize that redd persistence is a function of basin hydrology, sediment supply, and characteristics of the spawning fish. Hydrology controls the frequency and magnitude of bed mobilizing flows following spawning, while bed load supply (volume and caliber) controls the degree of textural fining and consequent bed mobility after spawning, as well as the potential for burial of redd features. The effectiveness of flows in terms of their magnitude and duration depend on hydroclimate (i.e., snowmelt, rainfall, or transitional hydrographs), while bed load supply depends on basin geology, land use, and natural disturbance regimes (e.g., wildfire). Location within the stream network may also influence redd persistence. In particular, lakes effectively trap sediment and regulate downstream flow, which may promote long-lived redds in stream reaches below lakes. These geomorphic controls are modulated by biological factors: fish species (size of fish controls size of redds and magnitude of streambed coarsening); life history (timing of spawning and

77 FR 33717 - Endangered and Threatened Species; Take of Anadromous Fish

Science.gov (United States)

2012-06-07

... applied for in good faith; (2) if granted and exercised, would not operate to the disadvantage of the... public comment. Project 1 is a study on the summer ecology of juvenile salmonids in streams of the... is a study on the ecology of juvenile salmonids in Tomales Bay, Pescadero Lagoon, and the Eel River...

Effects of ocean acidification on juvenile red king crab (Paralithodes camtschaticus and Tanner crab (Chionoecetes bairdi growth, condition, calcification, and survival.

Directory of Open Access Journals (Sweden)

William Christopher Long

Full Text Available Ocean acidification, a decrease in the pH in marine waters associated with rising atmospheric CO2 levels, is a serious threat to marine ecosystems. In this paper, we determine the effects of long-term exposure to near-future levels of ocean acidification on the growth, condition, calcification, and survival of juvenile red king crabs, Paralithodes camtschaticus, and Tanner crabs, Chionoecetes bairdi. Juveniles were reared in individual containers for nearly 200 days in flowing control (pH 8.0, pH 7.8, and pH 7.5 seawater at ambient temperatures (range 4.4-11.9 °C. In both species, survival decreased with pH, with 100% mortality of red king crabs occurring after 95 days in pH 7.5 water. Though the morphology of neither species was affected by acidification, both species grew slower in acidified water. At the end of the experiment, calcium concentration was measured in each crab and the dry mass and condition index of each crab were determined. Ocean acidification did not affect the calcium content of red king crab but did decrease the condition index, while it had the opposite effect on Tanner crabs, decreasing calcium content but leaving the condition index unchanged. This suggests that red king crab may be able to maintain calcification rates, but at a high energetic cost. The decrease in survival and growth of each species is likely to have a serious negative effect on their populations in the absence of evolutionary adaptation or acclimatization over the coming decades.

Seasonal growth and mortality of juveniles of Lampsilis fasciola (Bivalvia: Unionidae) released to a fish hatchery raceway

Science.gov (United States)

Hanlon, Shane D.; Neves, Richard J.

2006-01-01

Recent efforts to restore remnant or extirpated populations of freshwater mussels have focused on artificial propagation as an effective and practical conservation strategy. Although artificially cultured juveniles have been produced and released to the wild at various times of the year, no study has investigated the best time of year to release these juveniles. Newly metamorphosed juveniles of the wavyrayed lampmussel (Lampsilis fasciola) were released into a stream-fed fish hatchery raceway during March, June, and September. Growth and survival rates were measured 32, 52, 72, and 92 days post-metamorphosis. Juveniles released in June experienced the greatest growth and survival rates. Juveniles released in September and March experienced high mortality within the first month of release and exhibited poor growth in the cool water conditions typical of those seasons. Overwinter survival exhibited a size-dependent relationship.

Development of a systemwide predator control program: Stepwise implementation of a predation index, predator control fisheries, and evaluation plan in the Columbia River Basin. Section 1: Implementation. Annual report 1994

International Nuclear Information System (INIS)

Willis, C.F.; Young, F.R.

1995-09-01

The authors report the results from the forth year of a basinwide program to harvest northern squawfish (Ptychocheilus oregonensis) in an effort to reduce mortality due to northern squawfish predation on juvenile salmonids during their emigration from natal streams to the ocean. Earlier work in the Columbia River Basin suggested predation by northern squawfish on juvenile salmonids may account for most of the 10--20% mortality juvenile salmonids experience in each of eight Columbia and Snake River reservoirs. Modeling simulations based on work in John Day Reservoir from 1982 through 1988 indicated it is not necessary to eradicate northern squawfish to substantially reduce predation-caused mortality of juvenile salmonids. Instead, if northern squawfish were exploited at a 10--20% rate, reductions in numbers of larger, older fish resulting in restructuring of their population could reduce their predation on juvenile salmonids by 50% or more. Consequently, the authors designed and tested a sport-reward angling fishery and a commercial longline fishery in the John Day pool in 1990. They also conducted an angling fishery in areas inaccessible to the public at four dams on the mainstem Columbia River and at Ice Harbor Dam on the Snake River. Based on the success of these limited efforts, they implemented three test fisheries on a multi-pool, or systemwide, scale in 1991--a tribal longline fishery above Bonneville Dam, a sport-reward fishery, and a dam-angling fishery

Development of a Systemwide Predator Control Program, Section I : Northern Squawfish Management Program Implementation, 1994 annual report.

Energy Technology Data Exchange (ETDEWEB)

Willis, Charles F. (S.P. Cramer and Associates, Inc., Gresham, OR); Young, Franklin R. (Columbia Basin Fish and Wildlife Authority, Portland, OR)

1995-09-01

The authors report the results from the forth year of a basinwide program to harvest northern squawfish (Ptychocheilus oregonensis) in an effort to reduce mortality due to northern squawfish predation on juvenile salmonids during their emigration from natal streams to the ocean. Earlier work in the Columbia River Basin suggested predation by northern squawfish on juvenile salmonids may account for most of the 10--20% mortality juvenile salmonids experience in each of eight Columbia and Snake River reservoirs. Modeling simulations based on work in John Day Reservoir from 1982 through 1988 indicated it is not necessary to eradicate northern squawfish to substantially reduce predation-caused mortality of juvenile salmonids. Instead, if northern squawfish were exploited at a 10--20% rate, reductions in numbers of larger, older fish resulting in restructuring of their population could reduce their predation on juvenile salmonids by 50% or more. Consequently, the authors designed and tested a sport-reward angling fishery and a commercial longline fishery in the John Day pool in 1990. They also conducted an angling fishery in areas inaccessible to the public at four dams on the mainstem Columbia River and at Ice Harbor Dam on the Snake River. Based on the success of these limited efforts, they implemented three test fisheries on a multi-pool, or systemwide, scale in 1991--a tribal longline fishery above Bonneville Dam, a sport-reward fishery, and a dam-angling fishery.

APPLICATION OF SALMONIDS (SALMONIDAE N THE BIOMONITORING OF AQUATIC ENVIRONMENT (REVIEW

Directory of Open Access Journals (Sweden)

D. Yanovych

2016-03-01

Full Text Available Purpose. Due to the pollution of fisheries water bodies by industrial and agricultural waste waters, as well as by xenobiotics coming from other sources, taking into account a pridictable increase in the amounts of such effluents in the short and long terms, the problems related to the study of the effects of the pollutants of different nature and origin on aquatic organisms, especially fish, as well as a prediction of possible adverse consequences on aquatic ecosystems, becomes particularly important. The aim of our work was an analysis and synthesis of existing literature data concerning the indication in the biomonitoring of aquatic environments based on biological markers of salmonids as highly sensitive objects of fish fauna to external factors. Findings. The review summarizes and systematizes the data concerning the use of salmonids in biomonitoring studies. Furthermore, we highlighted and characterized the specificity of bioindication parameters of the aquatic environment state, such as the biochemical, genetic, physiological, morphological, histopathological, behavioral and population markers and noted the effects of hydroecosystem ecotoxication on different levels of biological organization (cell, individual, population, fish community. We also described the possibility of biological monitoring based on saprobic indexes identified for indicator species belonging to salmonids. Originality. In the article describes the structure, pros and cons of the use of specific biomarkers of individual salmonid fish and their populations for assessing the ecological status of aquatic environments. Practical value. The data given in the article can be used to improve the system of the ecological monitoring of aquatic environments by extending the range of indicator indices with organism and population biomarkers of highly sensitive salmonid species.

Incorporating episodicity into estimates of Critical Loads for juvenile salmonids in Scottish streams

Directory of Open Access Journals (Sweden)

E. E. Bridcut

2004-01-01

Full Text Available Critical Load (CL methodology is currently used throughout Europe to assess the risks of ecological damage due to sulphur and nitrogen emissions. Critical acid neutralising capacity (ANCCRIT is used in CL estimates for freshwater systems as a surrogate for biological damage. Although UK CL maps presently use an ANC value of 0 μeq l-1, this value has been based largely on Norwegian lake studies, in which brown trout is chosen as a representative indicator organism. In this study, an ANC value specific for brown trout in Scottish streams was determined and issues were addressed such as salmon and trout sensitivity in streams, episodicity, afforestation and complicating factors such as dissolved organic carbon (DOC and labile aluminium (Al-L. Catchments with significant forest cover were selected to provide fishless sites and to provide catchment comparisons in unpolluted areas. Chemical factors were the primary determinant with land use a secondary determinant of the distribution of salmonid populations at the twenty-six study sites. ANC explained more variance in brown trout density than pH. The most significant index of episodicity was percent of time spent below an ANC of 0 μeq l-1. An ANCCRIT value of 39 μeq l-1 was obtained based on a 50% probability of brown trout occurrence. The use of this revised ANCCRIT value in the CL equation improved the relationship between trout status and exceedance of CLs. Uncertainties associated with variations in Al-L at any fixed ANCCRIT, particularly within forested catchments, and the role of DOC in modifying the toxicity of Al-L are discussed. Keywords: Critical Load, Critical acid neutralising capacity, brown trout, episodes, streams

The malleable gut microbiome of juvenile rainbow trout (Oncorhynchus mykiss): Diet-dependent shifts of bacterial community structures.

Science.gov (United States)

Michl, Stéphanie Céline; Ratten, Jenni-Marie; Beyer, Matt; Hasler, Mario; LaRoche, Julie; Schulz, Carsten

2017-01-01

Plant-derived protein sources are the most relevant substitutes for fishmeal in aquafeeds. Nevertheless, the effects of plant based diets on the intestinal microbiome especially of juvenile Rainbow trout (Oncorhynchus mykiss) are yet to be fully investigated. The present study demonstrates, based on 16S rDNA bacterial community profiling, that the intestinal microbiome of juvenile Rainbow trout is strongly affected by dietary plant protein inclusion levels. After first feeding of juveniles with either 0%, 50% or 97% of total dietary protein content derived from plants, statistically significant differences of the bacterial gut community for the three diet-types were detected, both at phylum and order level. The microbiome of juvenile fish consisted mainly of the phyla Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria and Actinobacteria, and thus fits the salmonid core microbiome suggested in previous studies. Dietary plant proteins significantly enhanced the relative abundance of the orders Lactobacillales, Bacillales and Pseudomonadales. Animal proteins in contrast significantly promoted Bacteroidales, Clostridiales, Vibrionales, Fusobacteriales and Alteromonadales. The overall alpha diversity significantly decreased with increasing plant protein inclusion levels and with age of experimental animals. In order to investigate permanent effects of the first feeding diet-type on the early development of the microbiome, a diet change was included in the study after 54 days, but no such effects could be detected. Instead, the microbiome of juvenile trout fry was highly dependent on the actual diet fed at the time of sampling.

Delincuencia y responsabilidad penal juvenil en Colombia

Directory of Open Access Journals (Sweden)

Cristina Montalvo Velásquez

2011-01-01

England in 1815, “Juvenile delinquency is defined as the set of crimes, misdemeanors or socially reprehensible conduct, committed by young people considered by the law”. Each state is subject to its own legal system, for some it is the adolescent juvenile who commits sanctioned by the law regardless of their severity, other states only consider the youth as a juvenile offender who commits a serious criminal act.The phenomenon of juvenile delinquency is something that fits in the space of a society in which its material structure, and its consequent social formation, is in deep crisis. That younger as organized criminal gangs are telling us that result in the same general crime that has gripped society in perspective to survive materially. Capitalism is not only accumulation of wealth, but concentration of the very few hands, and all the legal and institutional system tends to favor this phenomenon because it is the structure above the capitalist mode of production. Just as adults are organized to commit crimes, do children and young people from an age in which they can see that society is not healthy and have no human future on it. Abandoned and subject to the violence that begets the system, they simply respond in a demonstration of conditioned reflexes that sustain survival in an instinctive way, “children do not know about laws but about ways to survive such a situation, the survival instinct does not ages or the regulations is liable to affect the.Key WordsJuvenile Delinquency, Youth Crime, Family Factors, criminal act, criminal liability.

Development of a rapid and efficient microinjection technique for gene insertion into fertilized salmonid eggs

Energy Technology Data Exchange (ETDEWEB)

Chandler, D.P.; Welt, M.; Leung, F.C.

1990-10-01

An efficient one-step injection technique for gene insertion into fertilized rainbow trout (Oncorhynchus mykiss) eggs is described, and basic parameters affecting egg survival are reported. Freshly fertilized rainbow trout eggs were injected in the perivitelline space with a recombinant mouse metallothionein-genomic bovine growth hormone (bGH) DNA construct using a 30-gauge hypodermic needle and a standard microinjection system. Relative to control, site of injection and DNA concentration did not affect the egg survival, but injections later than 3--4 hours post fertilization were detrimental. The injection technique permitted treatment of 100 eggs/hr with survivals up to 100%, resulting in a 4% DNA uptake rate as indicated by DNA dot blot analysis. Positive dot blot results also indicated that the injected DNA is able to cross the vitelline membrane and persist for 50--60 days post hatching, obviating the need for direct injection into the germinal disk. Results are consistent with previous transgenic fish work, underscoring the usefulness of the technique for generating transgenic trout and salmonids. 24 refs., 6 figs., 3 tabs.

Froude Number is the Single Most Important Hydraulic Parameter for Salmonid Spawning Habitat.

Science.gov (United States)

Gillies, E.; Moir, H. J.

2015-12-01

Many gravel-bed rivers exhibit historic straightening or embanking, reducing river complexity and the available habitat for key species such as salmon. A defensible method for predicting salmonid spawning habitat is an important tool for anyone engaged in assessing a river restoration. Most empirical methods to predict spawning habitat use lookup tables of depth, velocity and substrate. However, natural site selection is different: salmon must pick a location where they can successfully build a redd, and where eggs have a sufficient survival rate. Also, using dimensional variables, such as depth and velocity, is problematic: spawning occurs in rivers of differing size, depth and velocity range. Non-dimensional variables have proven useful in other branches of fluid dynamics, and instream habitat is no different. Empirical river data has a high correlation between observed salmon redds and Froude number, without insight into why. Here we present a physics based model of spawning and bedform evolution, which shows that Froude number is indeed a rational choice for characterizing the bedform, substrate, and flow necessary for spawning. It is familiar for Froude to characterize surface waves, but Froude also characterizes longitudinal bedform in a mobile bed river. We postulate that these bedforms and their hydraulics perform two roles in salmonid spawning: allowing transport of clasts during redd building, and oxygenating eggs. We present an example of this Froude number and substrate based habitat characterization on a Scottish river for which we have detailed topography at several stages during river restoration and subsequent evolution of natural processes. We show changes to the channel Froude regime as a result of natural process and validate habitat predictions against redds observed during 2014 and 2015 spawning seasons, also relating this data to the Froude regime in other, nearby, rivers. We discuss the use of the Froude spectrum in providing an indicator of

Effect of estradiol-17β on the sex ratio, growth and survival of juvenile common snook (Centropomus undecimalis)

OpenAIRE

Cristina Vaz Avelar de Carvalho; Gabriel Passini; Wanessa de Melo Costa; Beatriz Nunes Vieira; Vinicius Ronzani Cerqueira

2014-01-01

Sex control in fish is a promising technique for aquaculture, since it gives advantages associated with one sex. The aim of this study was to investigate the feminization of common snook (Centropomus undecimalis) by oral administration of two doses of estradiol-17β (50 and 100 mg E2 kg-1 feed) and control treatment for 45 days and to evaluate their effects on the sex ratio, growth and survival of common snook juveniles. After this period, fish were fed only with commercial feed without hormon...

Assessment of Smolt Condition for Travel Time Analysis Project, 1987-1997 Project Review.

Energy Technology Data Exchange (ETDEWEB)

Schrock, Robin M.; Hans, Karen M.; Beeman, John W. [US Geological Survey, Western Fisheries Research Center, Columbia River Research Laboratory, Cook, WA

1997-12-01

The assessment of Smolt Condition for Travel Time Analysis Project (Bonneville Power Administration Project 87-401) monitored attributes of salmonid smolt physiology in the Columbia and Snake River basins from 1987 to 1997, under the Northwest Power Planning Council Fish and Wildlife Program, in cooperation with the Smolt Monitoring Program of the Fish Passage Center. The primary goal of the project was to investigate the physiological development of juvenile salmonids related to migration rates. The assumption was made that the level of smolt development, interacting with environmental factos such as flow, would be reflected in travel times. The Fish Passage Center applied the physiological measurements of smolt condition to Water Budget management, to regulate flows so as to decrease travel time and increase survival.

Distribution and Joint Fish-Tag Survival of Juvenile Chinook Salmon Migrating through the Sacramento-San Joaquin River Delta, California, 2008

Science.gov (United States)

Holbrook, Christopher M.; Perry, Russell W.; Adams, Noah S.

2009-01-01

Acoustic telemetry was used to obtain the movement histories of 915 juvenile fall-run Chinook salmon (Oncorhynchus tshawytscha) through the lower San Joaquin River and Sacramento-San Joaquin Delta, California, in 2008. Data were analyzed within a release-recapture framework to estimate survival, route distribution, and detection probabilities among three migration pathways through the Delta. The pathways included the primary route through the San Joaquin River and two less direct routes (Old River and Turner Cut). Strong inferences about survival were limited by premature tag failure, but estimates of fish distribution among migration routes should be unaffected by tag failure. Based on tag failure tests (N = 66 tags), we estimated that only 55-78 percent of the tags used in this study were still functioning when the last fish was detected exiting the study area 15 days after release. Due to premature tag failure, our 'survival' estimates represent the joint probability that both the tag and fish survived, not just survival of fish. Low estimates of fish-tag survival could have been caused by fish mortality or fish travel times that exceeded the life of the tag, but we were unable to differentiate between the two. Fish-tag survival through the Delta (from Durham Ferry to Chipps Island by all routes) ranged from 0.05 +or- 0.01 (SE) to 0.06 +or- 0.01 between the two weekly release groups. Among the three migration routes, fish that remained in the San Joaquin River exhibited the highest joint fish-tag survival (0.09 +or- 0.02) in both weeks, but only 22-33 percent of tagged fish used this route, depending on the week of release. Only 4-10 percent (depending on week) of tagged fish traveled through Turner Cut, but no tagged fish that used this route were detected exiting the Delta. Most fish (63-68 percent, depending on week of release) migrated through Old River, but fish-tag survival through this route (0.05 +or- 0.01) was only about one-half that of fish that

Environmental conditions and prey-switching by a seabird predator impact juvenile salmon survival

Science.gov (United States)

Wells, Brian K.; Santora, Jarrod A.; Henderson, Mark J.; Warzybok, Pete; Jahncke, Jaime; Bradley, Russell W.; Huff, David D.; Schroeder, Isaac D.; Nelson, Peter; Field, John C.; Ainley, David G.

2017-01-01

Due to spatio-temporal variability of lower trophic-level productivity along the California Current Ecosystem (CCE), predators must be capable of switching prey or foraging areas in response to changes in environmental conditions and available forage. The Gulf of the Farallones in central California represents a biodiversity hotspot and contains the largest common murre (Uria aalge) colonies along the CCE. During spring, one of the West Coast's most important Chinook salmon (Oncorhynchus tshawytscha) populations out-migrates into the Gulf of the Farallones. We quantify the effect of predation on juvenile Chinook salmon associated with ecosystem-level variability by integrating long-term time series of environmental conditions (upwelling, river discharge), forage species abundance within central CCE, and population size, at-sea distribution, and diet of the common murre. Our results demonstrate common murres typically forage in the vicinity of their offshore breeding sites, but in years in which their primary prey, pelagic young-of-year rockfish (Sebastesspp.), are less available they forage for adult northern anchovies (Engraulis mordax) nearshore. Incidentally, while foraging inshore, common murre consumption of out-migrating juvenile Chinook salmon, which are collocated with northern anchovy, increases and population survival of the salmon is significantly reduced. Results support earlier findings that show timing and strength of upwelling, and the resultant forage fish assemblage, is related to Chinook salmon recruitment variability in the CCE, but we extend those results by demonstrating the significance of top-down impacts associated with these bottom-up dynamics. Our results demonstrate the complexity of ecosystem interactions and impacts between higher trophic-level predators and their prey, complexities necessary to quantify in order to parameterize ecosystem models and evaluate likely outcomes of ecosystem management options.

Environmental conditions and prey-switching by a seabird predator impact juvenile salmon survival

Science.gov (United States)

Wells, Brian K.; Santora, Jarrod A.; Henderson, Mark J.; Warzybok, Pete; Jahncke, Jaime; Bradley, Russell W.; Huff, David D.; Schroeder, Isaac D.; Nelson, Peter; Field, John C.; Ainley, David G.

2017-10-01

Due to spatio-temporal variability of lower trophic-level productivity along the California Current Ecosystem (CCE), predators must be capable of switching prey or foraging areas in response to changes in environmental conditions and available forage. The Gulf of the Farallones in central California represents a biodiversity hotspot and contains the largest common murre (Uria aalge) colonies along the CCE. During spring, one of the West Coast's most important Chinook salmon (Oncorhynchus tshawytscha) populations out-migrates into the Gulf of the Farallones. We quantify the effect of predation on juvenile Chinook salmon associated with ecosystem-level variability by integrating long-term time series of environmental conditions (upwelling, river discharge), forage species abundance within central CCE, and population size, at-sea distribution, and diet of the common murre. Our results demonstrate common murres typically forage in the vicinity of their offshore breeding sites, but in years in which their primary prey, pelagic young-of-year rockfish (Sebastes spp.), are less available they forage for adult northern anchovies (Engraulis mordax) nearshore. Incidentally, while foraging inshore, common murre consumption of out-migrating juvenile Chinook salmon, which are collocated with northern anchovy, increases and population survival of the salmon is significantly reduced. Results support earlier findings that show timing and strength of upwelling, and the resultant forage fish assemblage, is related to Chinook salmon recruitment variability in the CCE, but we extend those results by demonstrating the significance of top-down impacts associated with these bottom-up dynamics. Our results demonstrate the complexity of ecosystem interactions and impacts between higher trophic-level predators and their prey, complexities necessary to quantify in order to parameterize ecosystem models and evaluate likely outcomes of ecosystem management options.

Behavior and potential threats to survival of migrating lamprey ammocoetes and macrophthalmia

Energy Technology Data Exchange (ETDEWEB)

Moser, Mary L.; Jackson, Aaron D.; Lucas, Martyn C.; Mueller, Robert P.

2015-03-01

Upon metamorphosis, anadromous juvenile lamprey (macrophthalmia) exhibit distinct migration behaviors that take them from larval rearing habitats in streams to the open ocean. While poorly studied, lamprey larvae (ammocoetes) also engage in downstream movement to some degree. Like migrating salmon smolts, lamprey macrophthalmia undergo behavioral changes associated with a highly synchronized metamorphosis. Unlike salmon smolts, the timing of juvenile migration in lamprey is protracted and poorly documented. Lamprey macrophthalmia and ammocoetes are not strong swimmers, attaining maximum individual speeds of less than 1 m s-1, and sustained speeds of less than 0.5 m s-1. They are chiefly nocturnal and distribute throughout the water column, but appear to concentrate near the bottom in the thalweg of deep rivers. At dams and irrigation diversions, macrophthalmia can become impinged on screens or entrained in irrigation canals, suffer increased predation, and experience physical injury that may result in direct or delayed mortality. The very structures designed to protect migrating juvenile salmonids can be harmful to juvenile lamprey. Yet at turbine intakes and spillways, lampreys, which have no swim bladder, can withstand changes in pressure and shear stress large enough to injure or kill most teleosts. Lamprey populations are in decline in many parts of the world, with some species designated as species of concern for conservation that merit legally mandated protections. Hence, provisions for safe passage of juvenile lamprey are being considered at dams and water diversions in North America and Europe.

Introduction to SURPH.1 analysis of release-recapture data for survival studies

International Nuclear Information System (INIS)

Smith, S.G.; Skalski, J.R.; Schlechte, J.W.; Hoffmann, A.; Cassen, V.

1994-12-01

Program SURPH is the culmination of several years of research to develop a comprehensive computer program to analyze survival studies of fish and wildlife populations. Development of this software was motivated by the advent of the PIT-tag (Passive Integrated Transponder) technology that permits the detection of salmonid smolt as they pass through hydroelectric facilities on the Snake and Columbia Rivers in the Pacific Northwest. Repeated detections of individually tagged smolt and analysis of their capture-histories permits estimates of downriver survival probabilities. Eventual installation of detection facilities at adult fish ladders will also permit estimation of ocean survival and upstream survival of returning salmon using the statistical methods incorporated in SURPH.1. However, the utility of SURPH.1 far exceeds solely the analysis of salmonid tagging studies. Release-recapture and radiotelemetry studies from a wide range of terrestrial and aquatic species have been analyzed using SURPH.1 to estimate discrete time survival probabilities and investigate survival relationships. The interactive computing environment of SURPH.1 was specifically developed to allow researchers to investigate the relationship between survival and capture processes and environmental, experimental and individual-based covariates. Program SURPH.1 represents a significant advancement in the ability of ecologists to investigate the interplay between morphologic, genetic, environmental and anthropogenic factors on the survival of wild species. It is hoped that this better understanding of risk factors affecting survival will lead to greater appreciation of the intricacies of nature and to improvements in the management of wild resources. This technical report is an introduction to SURPH.1 and provides a user guide for both the UNIX and MS-Windows reg-sign applications of the SURPH software

Role of radiation therapy for 'juvenile' angiofibroma

Energy Technology Data Exchange (ETDEWEB)

Gudea, F.; Vega, M.; Canals, E.; Montserrat, J.M.; Valdano, J. (Univ. Autonoma de Barcelona (Spain). Hospital de la Santa Creu i Sant Pau (Spain))

1990-09-01

Juvenile nasopharyngeal angiofibroma (JNA) is a rare benign neoplasm which occurs primarily in male adolescents and is characterized by aggressive local growth. The controversy concerning appropriate treatment for patients with juvenile angiofibroma persists. Radiation therapy and survival resection have both been reported to be effective to control a high proportion of these tumours. The case reported here demonstrates a locally advanced JNA controlled by radiation therapy. (author).

Yolo Bypass Juvenile Salmon Utilization Study 2016—Summary of acoustically tagged juvenile salmon and study fish release, Sacramento River, California

Science.gov (United States)

Liedtke, Theresa L.; Hurst, William R.

2017-09-12

The Yolo Bypass is a flood control bypass in Sacramento Valley, California. Flood plain habitats may be used for juvenile salmon rearing, however, the potential value of such habitats can be difficult to evaluate because of the intermittent nature of inundation events. The Yolo Bypass Juvenile Salmon Utilization Study (YBUS) used acoustic telemetry to evaluate the movements and survival of juvenile salmon adjacent to and within the Yolo Bypass during the winter of 2016. This report presents numbers, size data, and release data (times, dates, and locations) for the 1,197 acoustically tagged juvenile salmon released for the YBUS from February 21 to March 18, 2016. Detailed descriptions of the surgical implantation of transmitters are also presented. These data are presented to support the collaborative, interagency analysis and reporting of the study findings.

Marine effect of introduced salmonids: Prey consumption by exotic steelhead and anadromous brown trout in the Patagonian Continental Shelf

Science.gov (United States)

Ciancio, J.; Beauchamp, D.A.; Pascual, M.

2010-01-01

On the basis of stable isotope analysis, we estimated the marine diet of the most abundant anadromous salmonid species in Patagonian Atlantic basins. The results were coupled with bioenergetic and population models to estimate the consumption of food by salmonids and was compared with that by seabirds, the most abundant top predators in the area. Amphipods were the main salmonid prey, followed by sprat, silversides, squid, and euphausiids. The total consumption, even assuming large anadromous salmonid populations, represented Limnology and Oceanography, Inc.

Food habits of Juvenile American Shad and dynamics of zooplankton in the lower Columbia River

Science.gov (United States)

Haskell, C.A.; Tiffan, K.F.; Rondorf, D.W.

2006-01-01

As many as 2.4 million adult American shad annually pass John Day Dam, Columbia River to spawn upriver, yet food web interactions of juvenile shad rearing in John Day Reservoir are unexplored. We collected zooplankton and conducted mid-water trawls in McNary (June-July) and John Day reservoirs (August-November) from 1994 through 1996 during the outmigration of subyearling American shad and Chinook salmon. Juvenile American shad were abundant and represented over 98% of the trawl catch in late summer. The five major taxa collected in zooplankton tows were Bosmina longirostris, Daphnia, cyclopoid cope-pods, rotifers, and calanoid copepods. We evaluated total crustacean zooplankton abundance and Daphnia biomass in relation to water temperature, flow, depth, diel period, and cross-sectional location using multiple regression. Differences in zooplankton abundance were largely due to differences in water temperature and flow. Spatial variation in total zooplankton abundance was observed in McNary Reservoir, but not in John Day Reservoir. Juvenile American shad generally fed on numerically abundant prey, despite being less preferred than larger bodied zooplankton. A decrease in cladoceran abundance and size in August coupled with large percentages of Daphnia in juvenile American shad stomachs indicated heavy planktivory. Smaller juvenile American shad primarily fed on Daphnia in August, but switched to more evasive copepods as the mean size of fish increased and Daphnia abundance declined. Because Daphnia are particularly important prey items for subyearling Chinook salmon in mainstem reservoirs in mid to late summer, alterations in the cladoceran food base is of concern for the management of outmigrating salmonids and other Columbia River fishes. ?? 2006 by the Northwest Scientific Association. All rights reserved.

Salmonids surveys, number of juvenile fish, fork length, and species diversity conducted in the Little Campbell Creek watershed, Alaska from 2010-11-01 to 2011-03-01 (NCEI Accession 0148761)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Over the past few years biologists and other researchers have encountered noticeable fish die-offs, mostly of young salmonid, in various stretches of Little Campbell...

Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program.

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Diefenderfer, Heida L. (Pacific Northwest National Laboratory)

2008-02-20

The purpose of this document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program, hereafter called 'the Estuary Program'. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows: (1) Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. (2) Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. (3) Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. (4) Maintain the food web to benefit salmonid performance. (5) Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. The goal leads to three primary management questions pertaining to the main focus of the Estuary Program: estuary habitat conservation and restoration. (1) Are the estuary habitat actions achieving the expected biological and environmental performance targets? (2) Are the offsite habitat actions in the estuary improving juvenile salmonid performance and which actions are most effective at addressing the limiting factors preventing achievement of habitat, fish, or wildlife performance objectives? (3) What are the limiting factors or threats in the estuary/ocean preventing the achievement of desired habitat or fish performance objectives? Performance measures

The effects of intermittent exposure to low pH and oxygen conditions on survival and growth of juvenile red abalone

Science.gov (United States)

Kim, T. W.; Barry, J. P.; Micheli, F.

2013-02-01

Exposure of nearshore animals to hypoxic, low pH waters upwelled from below the continental shelf and advected near the coast may be stressful to marine organisms and lead to impaired physiological performance. We mimicked upwelling conditions in the laboratory and tested the effect of fluctuating exposure to water with low pH and/or low oxygen levels on the mortality and growth of juvenile red abalone (Haliotis rufescens, shell length 5-10 mm). Mortality rates of juvenile abalone exposed to low pH (7.5, total scale) and low O2 (40% saturation, 5 mg L-1) conditions for periods of 3 to 6 h every 3-5 days over 2 weeks did not differ from those exposed to control conditions (O2: 100% saturation, 12 mg L-1; pH 8.0). However, when exposure was extended to 24 h repeated twice over a 15 day period, juveniles experienced higher mortality in the low oxygen treatments compared to control conditions, regardless of pH levels (pH 7.5 vs. 8.0). Growth rates were reduced significantly when juveniles were exposed to low pH or low oxygen treatments and the growth was lowest when low pH exposure was combined with low O2. Furthermore, individual variation of growth rate increased when they were exposed to low pH and low O2 conditions. These results indicate that prolonged exposure to low oxygen levels is detrimental for the survival of red abalone, whereas both pH and oxygen is a crucial factor for their growth. However, given the higher individual variation in growth rate, they may have an ability to adapt to extended exposure to upwelling conditions.

A Study of Stranding of Juvenile Salmon by Ship Wakes Along the Lower Columbia River Using a Before-and-After Design: Before-Phase Results

Energy Technology Data Exchange (ETDEWEB)

Pearson, Walter H.; Skalski, J R.; Sobocinski, Kathryn L.; Miller, Martin C.; Johnson, Gary E.; Williams, Greg D.; Southard, John A.; Buchanan, Rebecca A.

2006-02-01

Ship wakes produced by deep-draft vessels transiting the lower Columbia River have been observed to cause stranding of juvenile salmon. Proposed deepening of the Columbia River navigation channel has raised concerns about the potential impact of the deepening project on juvenile salmon stranding. The Portland District of the U.S. Army Corps of Engineers requested that the Pacific Northwest National Laboratory design and conduct a study to assess stranding impacts that may be associated with channel deepening. The basic study design was a multivariate analysis of covariance of field observations and measurements under a statistical design for a before and after impact comparison. We have summarized field activities and statistical analyses for the ?before? component of the study here. Stranding occurred at all three sampling sites and during all three sampling seasons (Summer 2004, Winter 2005, and Spring 2005), for a total of 46 stranding events during 126 observed vessel passages. The highest occurrence of stranding occurred at Barlow Point, WA, where 53% of the observed events resulted in stranding. Other sites included Sauvie Island, OR (37%) and County Line Park, WA (15%). To develop an appropriate impact assessment model that accounted for relevant covariates, regression analyses were conducted to determine the relationships between stranding probability and other factors. Nineteen independent variables were considered as potential factors affecting the incidence of juvenile salmon stranding, including tidal stage, tidal height, river flow, current velocity, ship type, ship direction, ship condition (loaded/unloaded), ship speed, ship size, and a proxy variable for ship kinetic energy. In addition to the ambient and ship characteristics listed above, site, season, and fish density were also considered. Although no single factor appears as the primary factor for stranding, statistical analyses of the covariates resulted in the following equations: (1) Stranding

Using a laboratory-based growth model to estimate mass- and temperature-dependent growth parameters across populations of juvenile Chinook Salmon

Science.gov (United States)

Perry, Russell W.; Plumb, John M.; Huntington, Charles

2015-01-01

To estimate the parameters that govern mass- and temperature-dependent growth, we conducted a meta-analysis of existing growth data from juvenile Chinook Salmon Oncorhynchus tshawytscha that were fed an ad libitum ration of a pelleted diet. Although the growth of juvenile Chinook Salmon has been well studied, research has focused on a single population, a narrow range of fish sizes, or a narrow range of temperatures. Therefore, we incorporated the Ratkowsky model for temperature-dependent growth into an allometric growth model; this model was then fitted to growth data from 11 data sources representing nine populations of juvenile Chinook Salmon. The model fit the growth data well, explaining 98% of the variation in final mass. The estimated allometric mass exponent (b) was 0.338 (SE = 0.025), similar to estimates reported for other salmonids. This estimate of b will be particularly useful for estimating mass-standardized growth rates of juvenile Chinook Salmon. In addition, the lower thermal limit, optimal temperature, and upper thermal limit for growth were estimated to be 1.8°C (SE = 0.63°C), 19.0°C (SE = 0.27°C), and 24.9°C (SE = 0.02°C), respectively. By taking a meta-analytical approach, we were able to provide a growth model that is applicable across populations of juvenile Chinook Salmon receiving an ad libitum ration of a pelleted diet.

Feeding Activity, Rate of Consumption, Daily Ration and Prey Selection of Major Predators in John Day Reservoir, 1984 : Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Gray, Gerard A.; United States. Bonneville Power Administration; U.S. Fish and Wildlife Service; National Fishery Research Center (U.S.)

1986-07-01

The extent of predation on juvenile salmonids in John Day Reservoir was determined. Salmonids were the single most important food item by weight for northern squawfish (Ptychocheilus oregonensis) in the restricted zones at McNary tailrace and John Day forebay during all sampling periods. Salmonids accounted for 18.1% of the weight in the diet of walleyes (Stizostedion vitreum vitreum) in 1984 which was at least twice that found in previous years. In smallmouth bass (Micropterus dolomieui) salmonids contributed little to their diet whereas for channel catfish (Ictalurus punctatus) fish accounted for 64.1% of the weight in their diet with salmonids responsible for approximately half of this weight. An intensive search of the fisheries literature was conducted to review various fish capture and control techniques which might have potential as predation control measures for the major predators of juvenile salmonids in the Columbia River system. Most prey protection measures were judged to have high potential and direct predator control measures were judged to have moderate or low potential.

Environmental Assessment : Squawfish Management Program : Final.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1992-05-01

Bonneville Power Administration (BPA) proposes to decrease the number of northern squawfish (Ptychocheilus oregonensis) in reservoirs in the Columbia River system. The goal of the Squawfish Management Program is to reduce losses of outmigrating juvenile salmon and steelhead (salmonids) to northern squawfish predation. The objective is to reduce the number of northern squawfish that feed on juvenile salmonids (smolts) by 10 to 20 percent to alter the age and size structure of the northern squawfish population. The hypothesis, based on computer modeling, indicates that sustained northern squawfish harvest (5 to 10 years) and the resultant population restructuring may reduce losses of juvenile salmonids to predation by up to 50 percent or more within 10 years. The proposed action would target northern squawfish 11 inches and longer, the size in which northern squawfish being preying significantly on juvenile salmonids. BPA proposes to fund three types of fisheries to harvest northern squawfish. BPA also proposes to fund monitoring activities of these fisheries to determine whether desired or other results occur. The three fisheries methods proposed are: (1) commercial Tribal fishing; (2) sport reward fishing; and (3) fishing from restricted areas of each dam ( dam angling''). These fisheries were tested in 1990 and 1991.

Development of a systemwide predator control program: Stepwise implementation of a predation index, predator control fisheries, and evaluation plan in the Columbia River Basin. Volume 2 -- Evaluation: 1993 Annual report

International Nuclear Information System (INIS)

Willis, C.F.; Ward, D.L.

1995-06-01

An attempt was made to determine the extent to which northern squawfish predation on juvenile salmonids is a problem in the Columbia River Basin, and to evaluate how effectively fisheries can be used to control northern squawfish populations and reduce juvenile salmonid losses to predation. These studies were initiated as part of a basinwide program to control northern squawfish predation and reduce mortality of juvenile salmonids on their migration to the ocean. Modeling simulations based on work in the John Day Reservoir from 1982 through 1988 indicated that if northern squawfish larger than 250 mm fork length were exploited, at a rate of 10--20%, reductions in their numbers and restructuring of their populations could reduce their predation on juvenile salmonids by 50% or more. The authors evaluated the success of three test fisheries conducted in 1993--a sport-reward fishery, a dam-angling fishery, and a trap-net fishery, to achieve a 10--20% exploitation rate on northern squawfish. The authors also began evaluating the response of northern squawfish populations to sustained fisheries. In addition, the authors gathered information regarding the economic, social, and legal feasibility of sustaining each fishery, and report on the structure and function of the fish collection and distribution system

The footprint of salmonids on river morphology

Science.gov (United States)

Hassan, M. A.; Tonina, D.

2012-12-01

Female salmonids dig a pit in the streambed where they lay their eggs, which then cover with sediment from a second pit forming an egg nest call redd. This formation results in a shape resembling a dune with an amplitude, which is the vertical difference between bottom of the pit and crest of the hump, varying from few centimetres (for small fish, chum or sockeye salmon) to tenths of a meter (for large fish, Chinook salmon). During redd construction, salmonids alter streambed topography, winnow away fine sediment and mix streambed material within a layer as thick as 50 cm, for the large chinook salmon. The spawning activities may result in additional roughness at the local scale due to redds. However, redd construction may smooth large-scale topography reducing roughness due the macro-bedform. These topographical changes vary streambed roughness, which in turn may affect shear stress distribution. Redds have been suggested to increase the overall flow resistance due to form drag resulting in lower grain shear stress and less particle mobility. However, the mixing of the sediment could prevent armouring of the streambed surface allowing higher than with armouring sediment transport. Here, we use detailed pre- and post-spawning bathymetries coupled with accurate 2-dimensional hydraulic numerical modelling to test which of these two effects has potentially more impact on sediment transport. Our results show that topographical roughness added by sockeye salmons, which build small redds with 15cm amplitude and 1 meter wavelength (longitudinal length of a redd), has negligible effect on shear stress at the reach-scale and limited at the local scale. Conversely, sediment mixing has an important effect on reducing armouring, increasing sediment mobility, which results in potentially more sediment transport in reaches with than without redds. Consequently, salmonid bioturbation due to mass-spawning fish can be a dominant element for sediment transport in mountain drainage

Behavioral profiles of the captive juvenile whooping crane (Grus americana) as an indicator of reintroduction behavior and survival

Science.gov (United States)

Kreger, M.D.

2003-01-01

Predation by bobcats (Lynx rufus) has been the greatest cause of mortality of whooping cranes (Grus americana) in the reintroduced population in Florida. This study investigated whether the behavior of juvenile cranes during captive rearing and shortly after release can be used to predict their chances of survival once released in the wild. This study also examined differences in behavior based on rearing treatments and whether differences observed during rearing continued at the release site. Experimental rearing treatments were parent reared (PR), hand reared (RR), and hand reared with exercise (HRE). Two annual cycles of cranes were observed from hatch to 20 weeks of age in captivity (n=56 birds). Post-release bebavioral data were collected at the release site for a minimum of two weeks (n=34 birds), with mortality data collected up to one year post release (n=38 birds). Behavioral time budgets were compared using repeated measures ANOVA. Logistic regression was used to build a model to identify behaviors that were associated with first-year survival. During rearing, PR birds were the most vigilant. There were no behavioral differences between HR and HRE birds. Generally, rearing treatments had few long-term effects on the post-release behavior of the birds. The main behavioral differences during rearing and after release were the frequency of bouts and the percentage of time spent performing different behaviors. This may be attributed to foraging strategies and adaptation from captive conditions to the wild. Survival was not related to rearing treatment. Fifty-five percent of the birds survived the first year post-release based upon data pooled over two years. During rearing, the frequency of foraging bouts was positively correlated to survival. Survival was negatively correlated to the frequency of walking bouts during rearing, and release weight of the birds. These correlations accounted for 32 percent of the variability in survival. At the release site, 20

Development of an Index to Bird Predation of Juvenile Salmonids within the Yakima River, 2000 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Grassley, James M.; Grue, Christian E.; Major, III, Walter (University of Washington, School of Aquatic and Fishery Science, Seattle, WA)

2002-01-01

Avian predation of fish is suspected to contribute to the loss of juvenile spring chinook salmon in the Yakima Basin, potentially constraining natural production. In 1997 and 1998, the Yakama/Klickitat Fisheries Project (YKFP) and the Washington Department of Fish and Wildlife (WDFW)--whose goal is to increase natural production historically present within the Yakima River--initiated investigations to assess the feasibility of developing an index to avian predation of juvenile salmon within the river. This research--conducted by Dr. Steve Mathews and David Phinney of the University of Washington--confirmed that Ring-billed Gulls and Common Mergansers were the primary avian predators of juvenile salmon, and that under certain conditions could impact migrating smolt populations. Beginning in 1999, the Washington Cooperative Fish and Wildlife Research Unit (WACFWRU) was asked by the YKFP and the WDFW to continue development of avian consumption indices. Monitoring methods developed by Phinney et al. (1998) were adopted (with modifications) and monitoring of impacts to juvenile salmon along river reaches and at areas of high predator/prey concentrations (colloquially referred to as ''hotspots'') continued through 2000. In 2000, piscivorous birds were counted from river banks at hotspots and from a raft or drift boat along river reaches. Consumption by gulls at Hotspots was based on direct observations of foraging success and modeled abundance; consumption by all other piscivorous birds was estimated using published dietary requirements and modeled abundance. Further development of the avian consumption index model provided an estimation of smolt consumption for the 2000 survey season. Seasonal patterns of avian piscivore abundance were identified, diurnal patterns of gull abundance at hotspots were identified, predation indices were calculated for hotspots and spring and summer river reaches, and the efficacy of aerial surveys for estimating bird

Rainfall during parental care reduces reproductive and survival components of fitness in a passerine bird

OpenAIRE

?berg, Meit; Arlt, Debora; P?rt, Tomas; Laugen, Ane T; Eggers, S?nke; Low, Matthew

2014-01-01

Adverse weather conditions during parental care may have direct consequences for offspring production, but longer-term effects on juvenile and parental survival are less well known. We used long-term data on reproductive output, recruitment, and parental survival in northern wheatears (Oenanthe oenanthe) to investigate the effects of rainfall during parental care on fledging success, recruitment success (juvenile survival), and parental survival, and how these effects related to nestling age,...

Vertebrae classification models - Validating classification models that use morphometrics to identify ancient salmonid (Oncorhynchus spp.) vertebrae to species

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Using morphometric characteristics of modern salmonid (Oncorhynchus spp.) vertebrae, we have developed classification models to identify salmonid vertebrae to the...

Fish distribution studies near N Reactor, Summer 1983

Energy Technology Data Exchange (ETDEWEB)

Dauble, D.D.; Page, T.L.

1984-06-01

This report summarizes field studies that were initiated in July 1983 to provide estimates of the relative distribution of late-summer outmigrant juvenile salmonids and juvenile resident fish upstream of the N Reactor 009 Outfall. Chinook salmon are among the fish species most sensitive to thermal effects, and impacts to the juvenile outmigrant populations are of particular concern to state and federal regulatory and fisheries management agencies. Therefore, the distribution studies were conducted from late July through September, a period when high ambient river temperatures and low river flows make these salmonid populations most susceptible to thermal effects. In addition, data were not available on the spatial distribution of outmigrant juvenile chinook salmon in late summer. Information on the relative distribution of resident fish populations was also gathered. Previous studies of midstream distribution of juvenile resident fish were limited to a description of ichthyoplankton populations (Beak Consultants, Inc. 1980 Page et al. 1982), and no data were available on vertical or horizontal distribution of juvenile resident fish species near N Reactor. Relative densities and spatial distribution estimates of juvenile salmonid and resident fish species will be used in conjunction with laboratory thermal effects studies (Neitzel et al. 1984) and with plume characterization studies (Ecker et al. 1983) to assess potential impacts of thermal discharge on fish populations near N Reactor.

Effect of silver nanoparticles on the metabolic rate, hematological response, and survival of juvenile white shrimp Litopenaeus vannamei.

Science.gov (United States)

Juarez-Moreno, Karla; Mejía-Ruiz, Claudio Humberto; Díaz, Fernando; Reyna-Verdugo, Horacio; Re, Ana Denisse; Vazquez-Felix, Edgar F; Sánchez-Castrejón, Edna; Mota-Morales, Josué D; Pestryakov, Alexey; Bogdanchikova, Nina

2017-02-01

White spot syndrome virus (WSSV) is highly lethal and contagious in shrimps; its outbreaks causes an economic crisis for aquaculture. Several attempts have been made to treat this disease; however, to date, there is no effective cure. Because of their antimicrobial activities, silver nanoparticles (AgNPs) are the most studied nanomaterial. Although the antiviral properties of AgNPs have been studied, their antiviral effect against viral infection in aquaculture has not been reported. The AgNPs tested herein are coated with polyvinylpyrrolidone (PVP) and possess multiple international certifications for their use in veterinary and human applications. The aim of this work was to evaluate the survival rate of juvenile white shrimps (Litopenaeus vannamei) after the intramuscular administration of AgNPs. For this, different concentrations of metallic AgNPs and PVP alone were injected into the organisms. After 96 h of administration, shrimp survival was more than 90% for all treatments. The oxygen consumption routine rate and total hemocyte count remained unaltered after AgNP injection, reflecting no stress caused. We evaluated whether AgNPs had an antiviral effect in shrimps infected with WSSV. The results revealed that the survival rate of WSSV-infected shrimps after AgNP administration was 80%, whereas the survival rate of untreated organisms was only 10% 96 h after infection. These results open up the possibility to explore the potential use of AgNPs as antiviral agents for the treatment of diseases in aquaculture organisms, particularly the WSSV in shrimp culture. Copyright © 2016 Elsevier Ltd. All rights reserved.

Fish embryo and juvenile size under hypoxia in the mouth-brooding African cichlid Pseudocrenilabrus multicolor

Institute of Scientific and Technical Information of China (English)

E.E.REARDON; L.J.CHAPMAN

2012-01-01

We used a field survey and a laboratory rearing experiment to (a) examine response (size and survival) to life-long hypoxia in offspring of the African maternal mouth-brooding cichlid Pseudocrenilabrus multicolor victoriae (Seegers) and (b) explore the degree to which developmental response can be environmentally-induced.Embryo size metrics were quantified in 9 field populations across a range of dissolved oxygen (DO) concentrations.In the laboratory,first generation (F1) broods of low-DO origin were reared under high or low DO.Brooding period was quantified for the mothers; and egg size,egg metabolic rate and juvenile size-at-release were quantified in their (F2) offspring.The F2 offspring were split and grown for 3 months post-release under high or low DO,and juvenile size and survival were quantified.In the field survey,across stages,embryos from low-DO field populations were shorter and weighed less than embryos from high-DO populations.In the laboratory experiment,F2 eggs and juveniles-at-release from mother's mouth did not differ in mass,length,survival regardless of development DO environment.However,juveniles diverged in size after leaving mother's mouth,exhibiting smaller size when grown under low DO.Size differences in embryo size across field populations and divergence in embryo size after release from the mother's mouthsupport predictions for smaller body size under hypoxia.There was no evidence for negative effects on survival of juveniles after 3 months.Brooding period was 16％ shorter in females reared under low DO suggesting that hypoxia may accelerate embryo development.This work provides insights into how bearer fishes respond to hypoxic stress relative to fishes with no post-spawning parental care; a shorter brooding interval and smaller body size may provide an optimal solution to parent and embryo survival under hypoxia in brooding fishes.

Juvenile Lost River and shortnose sucker year class strength, survival, and growth in Upper Klamath Lake, Oregon, and Clear Lake Reservoir, California—2016 Monitoring Report

Science.gov (United States)

Burdick, Summer M.; Ostberg, Carl O.; Hoy, Marshal S.

2018-04-20

Executive SummaryThe largest populations of federally endangered Lost River (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) exist in Upper Klamath Lake, Oregon, and Clear Lake Reservoir, California. Upper Klamath Lake populations are decreasing because adult mortality, which is relatively low, is not being balanced by recruitment of young adult suckers into known spawning aggregations. Most Upper Klamath Lake juvenile sucker mortality appears to occur within the first year of life. Annual production of juvenile suckers in Clear Lake Reservoir appears to be highly variable and may not occur at all in very dry years. However, juvenile sucker survival is much higher in Clear Lake, with non-trivial numbers of suckers surviving to join spawning aggregations. Long-term monitoring of juvenile sucker populations is needed to (1) determine if there are annual and species-specific differences in production, survival, and growth, (2) to identify the season (summer or winter) in which most mortality occurs, and (3) to help identify potential causes of high juvenile sucker mortality, particularly in Upper Klamath Lake.We initiated an annual juvenile sucker monitoring program in 2015 to track cohorts in 3 months (June, August, and September) annually in Upper Klamath Lake and Clear Lake Reservoir. We tracked annual variability in age-0 sucker apparent production, juvenile sucker apparent survival, and apparent growth. Using genetic markers, we were able to classify suckers as one of three taxa: shortnose or Klamath largescale suckers, Lost River, or suckers with genetic markers of both species (Intermediate Prob[LRS]). Using catch data, we generated taxa-specific indices of year class strength, August–September apparent survival, and overwinter apparent survival. We also examined prevalence and severity of afflictions such as parasites, wounds, and deformities.Indices of year class strength in Upper Klamath Lake were similar for shortnose suckers in 2015

Effects of fine sediment, hyporheic flow, and spawning site characteristics on survival and development of bull trout embryos

Science.gov (United States)

Bowerman, Tracy; Neilson, Bethany; Budy, Phaedra

2014-01-01

Successful spawning is imperative for the persistence of salmonid populations, but relatively little research has been conducted to evaluate factors affecting early life-stage survival for bull trout (Salvelinus confluentus), a threatened char. We conducted a field experiment to assess the relationship between site-specific environmental factors and bull trout embryo survival and fry emergence timing. Survival from egg to hatch was negatively related to percent fine sediment (bull trout egg survival, but early life-stage success may ultimately be limited by intrusion of fine sediment into the incubation environment.

Variation in salmonid life histories: patterns and perspectives.

Science.gov (United States)

Mary F. Willson

1997-01-01

Salmonid fishes differ in degree of anadromy, age of maturation, frequency of reproduction, body size and fecundity, sexual dimorphism, breeding season, morphology, and, to a lesser degree, parental care. Patterns of variation and their possible significance for ecology and evolution and for resource management are the focus of this review.

Interannual differences in growth and hatch-date distributions of early juvenile European anchovy in the Bay of Biscay: implications for recruitment

KAUST Repository

Aldanondo, Naroa

2016-01-22

© 2016 John Wiley & Sons Ltd. In order to understand better the recruitment variability in European anchovy in the Bay of Biscay, it is important to investigate the processes that affect survival during the early life stages. Anchovy juvenile growth trajectories and hatch-date distributions were inferred over a 3-year period based on otolith microstructure analysis. Otolith growth trajectories showed a characteristic shape depending on their hatch-date timing. Earlier-born juveniles had notably broader maximum increments than later born conspecifics, resulting in higher growth rates. This observation suggests that early hatching would be beneficial for larval and juvenile growth, and, therefore, survival. The estimated juvenile hatch-date distributions were relatively narrow compared with the extended anchovy spawning season (March-August) in the Bay of Biscay and indicated that only individuals originated mainly from the summer months (June-August) survived until autumn. Hatch-date distributions were markedly different among years and seemed to influence the interannual recruitment strength of anchovy. We conclude that years characterized by juvenile survivors originating from the peak spawning period (May and June) would lead to considerable recruitment success. Downwelling events during the peak spawning period seem to affect larval survival.

Homeopathy outperforms antibiotics treatment in juvenile scallop Argopecten ventricosus: effects on growth, survival, and immune response.

Science.gov (United States)

Mazón-Suástegui, José Manuel; García-Bernal, Milagro; Saucedo, Pedro Enrique; Campa-Córdova, Ángel; Abasolo-Pacheco, Fernando

2017-02-01

Mortality from vibriosis in mollusk production is attributed to pathogenic bacteria, particularly Vibrio alginolyticus. Use of increasingly potent antibiotics has led to bacterial resistance and increased pathogenicity. Alternatives in sanitation, safety, and environmental sustainability are currently under analysis. To-date, homeopathy has been investigated in aquaculture of freshwater fish, but not in marine mollusks. The effect of the homeopathic complexes in the growth, survival, and immune response of the Catarina scallop Argopecten ventricosus were assessed. A bioassay to assess the potential of homeopathy in improving cultivation of juvenile A. ventricosus was conducted for 21 days, with a final challenge of 120 h with V. alginolyticus. The experimental design included two homeopathic formulas The homeopathic complex Passival, consisting of Passiflora incarnata 30 CH, Valeriana officinalis 30 CH, Ignatia amara 30 CH and Zincum valerianicum 30 CH plus Phosphoricum acid 30 CH (treatment TH1) or Silicea terra 30 CH (TH2), two antibiotics (ampicillin = AMP, oxytetracycline = OXY), and two reference treatments (without homeopathic or antibiotic treatment = CTRL, ethanol 30° GL = ETH). Additionally, a negative control CTRL- (untreated/uninfected) is included in the challenge test. Juvenile scallops (4.14 ± 0.06 mm, 13.33 mg wet weight) were cultivated in 4 L tanks provided with aerated, filtered (1 μm), and UV-sterilized seawater that was changed every third day. They were fed a blend of the microalgae Isochrysis galbana and Chaetoceros calcitrans (150,000 cells mL -1 twice a day). All treatments were directly added to the tank water and then 500 mL challenge units were inoculated with 1 × 10 7  CFU/mL (LD 50 ) of V. alginolyticus. Juveniles grew significantly larger and faster in height and weight with TH2 compared to the ETH and CTRL (P homeopathy is a viable treatment for this mollusk to reduce use of antibiotics in scallops and its

Identification of Two Pathogenic Aeromonas Species Isolated during Production Related Epizootics from Juvenile Burbot Lota lota maculosa.

Science.gov (United States)

Terrazas, Marc M; Anderson, Cort L; Jacobs, Sarah J; Cain, Kenneth D

2018-05-25

In response to population declines of Burbot Lota lota maculosa, conservation aquaculture methods have been developed for this species. In general, Burbot are relatively resistant to many salmonid pathogens; however, cultured juvenile Burbot have experienced periodic epizootic disease outbreaks during production. A series of trials were conducted to determine the virulence of select bacteria isolated from juvenile Burbot following outbreaks that occurred in 2012 and 2013 at the University of Idaho's Aquaculture Research Institute. Initial clinical diagnostics and sampling resulted in the isolation of numerous putative bacterial pathogens. To determine which bacteria were the most likely causative agents contributing to these epizootics, juvenile Burbot were injectied intraperitoneally (IP) with select bacteria in log phase growth. Mortality associated with specific isolates was recorded, and more comprehensive challenges followed this initial screening. These challenges used side-by-side IP and immersion methods to expose Burbot to potential pathogens. The challenges resulted in significantly higher mortalities in fish following IP injection of two Aeromonas sp. isolates compared to controls (P ≤ 0.01), but no difference in mortality for immersion challenged groups was observed (P = 0.42). Results demonstrate that two isolates (Aeromonas sp.) cultured from the epizootics are virulent to Burbot. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

ADULT COHO SALMON AND STEELHEAD USE OF BOULDER WEIRS IN SOUTHWEST OREGON STREAMS

Science.gov (United States)

The placement of log and boulder structures in streams is a common and often effective technique for improving juvenile salmonid rearing habitat and increasing fish densities. Less frequently examined has been the use of these structures by adult salmonids. In 2004, spawner densi...

[Child-juvenile prostitution: a systematic literature review].

Science.gov (United States)

Ribeiro, Moneda Oliveira; Dias, Aretuzza de Fátima

2009-06-01

The purpose of this study was to understand how infant-juvenile prostitution is being explained by researchers through an extensive bibliographical survey on national and international scientific sources. It was possible to access 20 references in full text form, which were analyzed according to the Content Analysis method. The analysis consisted in answering how infant-juvenile prostitution is represented by the author in relation to the concepts, causes, effects and solutions described in the references. It was found that the authors approached the subject as a way of survival, resulting from an unequal society, adult-centered and male chauvinist causing mental and physical diseases in children.

Many Species, Many Threats: A Composite Risk Assessment of Climate Impacts for Salmonids in the Pacific Northwest

Science.gov (United States)

Graham, M. C.; Greene, C.; Beechie, T. J.; Raymond, C.

2016-02-01

The life cycles of salmonid species span freshwater, estuarine, and marine environments, exposing these economically, ecologically, and culturally important species to a wide variety of climate change threats. The diverse life histories of salmonids make them differentially vulnerable to climate change based on their use of different habitat types and the variability in climate change threats across these habitat types. Previous studies have focused mainly on assessing the vulnerability of particular life stages for a few species. Hence, we lack a broad perspective on how multiple climate threats are expected to impact the entire salmonid community, which spend much of their lives in marine waters. This lack of knowledge hampers our ability to prioritize various adaptation strategies for salmonid conservation. In order to conduct a more extensive vulnerability study of salmonids, we performed a life cycle-based risk assessment of climate change threats for nine species of salmonids (species within Oncorhynchus, Salvelinus, and Prosopium genera) inhabiting the Skagit River watershed, which is subject to an array of climate impacts. Our risk assessment integrated projections of impacts from various climate threats in freshwater, estuarine, and marine ecosystems with expert-based assessments of species-specific sensitivity and exposure. We found that projections (multiple global climate models under moderate emission scenarios) of both changes in magnitude and frequency of three flow-related freshwater impacts (flooding, low flows, and suspended sediment pulses) were more severe than threats in estuarine and marine habitats for which we could obtain projections. Combining projections with expert-based sensitivity and exposure scores revealed that these three threats exhibited the highest risk across all species. Of the nine species, the four most vulnerable were Chinook and coho salmon, steelhead, and bull trout. Even though these salmonids spend much of their lives

Food availability and pCO2 impacts on planulation, juvenile survival, and calcification of the azooxanthellate scleractinian coral, Balanophyllia elegans

Science.gov (United States)

Crook, E. D.; Cooper, H.; Potts, D. C.; Lambert, T.; Paytan, A.

2013-05-01

Ocean acidification, the assimilation of atmospheric CO2 by the oceans that decreases the pH and CaCO3 saturation state (Ω) of seawater, is projected to have severe consequences for calcifying organisms. Strong evidence suggests that tropical reef-building corals containing algal symbionts (zooxanthellae) will experience dramatic declines in calcification over the next century. The responses of azooxanthellate corals to ocean acidification are less well understood, and because they cannot obtain extra photosynthetic energy from symbionts, they provide a system for studying the direct effects of acidification on the energy available for calcification. The orange cup coral Balanophyllia elegans is a solitary, azooxanthellate scleractinian species common on the California coast where it thrives in the low pH waters of an upwelling regime. During an 8 month study, we addressed the effects of three pCO2 treatments (410, 770, and 1230 μatm) and two feeding frequencies (High Food and Low Food) on adult Balanophyllia elegans planulation (larval release) rates, and on the survival, growth, and calcification of their juvenile offspring. Planulation rates were affected by food level but not pCO2, while juvenile survival was highest under 410 μatm and High Food conditions. Our results suggest that feeding rate has a greater impact on calcification of B. elegans than pCO2. Net calcification was positive even at 1230 μatm (~ 3 times current atmospheric pCO2), although the increase from 410 to 1230 μatm reduced overall calcification by ~ 25-45%, and reduced skeletal density by ~ 35-45%. Higher pCO2 also altered aragonite crystal morphology significantly. We discuss how feeding frequency affects azooxanthellate coral calcification, and how B. elegans may respond to ocean acidification in coastal upwelling waters.

The effect of rapid and sustained decompression on barotrauma in juvenile brook lamprey and Pacific lamprey: implications for passage at hydroelectric facilities

Energy Technology Data Exchange (ETDEWEB)

Colotelo, Alison HA; Pflugrath, Brett D.; Brown, Richard S.; Brauner, Colin J.; Mueller, Robert P.; Carlson, Thomas J.; Deng, Zhiqun; Ahmann, Martin L.; Trumbo, Bradly A.

2012-10-01

Fish passing downstream through hydroelectric facilities may pass through hydroturbines where they experience a rapid decrease in barometric pressure as they pass by turbine blades, which can lead to barotraumas including swim bladder rupture, exopthalmia, emboli, and hemorrhaging. In juvenile Chinook salmon, the main mechanism for injury is thought to be expansion of existing gases (particularly those present in the swim bladder) and the rupture of the swim bladder ultimately leading to exopthalmia, emboli and hemorrhaging. In fish that lack a swim bladder, such as lamprey, the rate and severity of barotraumas due to rapid decompression may be reduced however; this has yet to be extensively studied. Another mechanism for barotrauma can be gases coming out of solution and the rate of this occurrence may vary among species. In this study, juvenile brook and Pacific lamprey acclimated to 146.2 kPa (equivalent to a depth of 4.6 m) were subjected to rapid (<1 sec; brook lamprey only) or sustained decompression (17 minutes) to a very low pressure (13.8 kPa) using a protocol previously applied to juvenile Chinook salmon. No mortality or evidence of barotraumas, as indicated by the presence of hemorrhages, emboli or exopthalmia, were observed during rapid or sustained decompression, nor following recovery for up to 120 h following sustained decompression. In contrast, mortality or injury would be expected for 97.5% of juvenile Chinook salmon exposed to a similar rapid decompression to these very low pressures. Additionally, juvenile Chinook salmon experiencing sustained decompression died within 7 minutes, accompanied by emboli in the fins and gills and hemorrhaging in the tissues. Thus, juvenile lamprey may not be susceptible to barotraumas associated with hydroturbine passage to the same degree as juvenile salmonids, and management of these species should be tailored to their specific morphological and physiological characteristics.

Invasion versus isolation: trade-offs in managing native salmonids with barriers to upstream movement.

Science.gov (United States)

Fausch, Kurt D; Rieman, Bruce E; Dunham, Jason B; Young, Michael K; Peterson, Douglas P

2009-08-01

Conservation biologists often face the trade-off that increasing connectivity in fragmented landscapes to reduce extinction risk of native species can foster invasion by non-native species that enter via the corridors created, which can then increase extinction risk. This dilemma is acute for stream fishes, especially native salmonids, because their populations are frequently relegated to fragments of headwater habitat threatened by invasion from downstream by 3 cosmopolitan non-native salmonids. Managers often block these upstream invasions with movement barriers, but isolation of native salmonids in small headwater streams can increase the threat of local extinction. We propose a conceptual framework to address this worldwide problem that focuses on 4 main questions. First, are populations of conservation value present (considering evolutionary legacies, ecological functions, and socioeconomic benefits as distinct values)? Second, are populations vulnerable to invasion and displacement by non-native salmonids? Third, would these populations be threatened with local extinction if isolated with barriers? And, fourth, how should management be prioritized among multiple populations? We also developed a conceptual model of the joint trade-off of invasion and isolation threats that considers the opportunities for managers to make strategic decisions. We illustrated use of this framework in an analysis of the invasion-isolation trade-off for native cutthroat trout (Oncorhynchus clarkii) in 2 contrasting basins in western North America where invasion and isolation are either present and strong or farther away and apparently weak. These cases demonstrate that decisions to install or remove barriers to conserve native salmonids are often complex and depend on conservation values, environmental context (which influences the threat of invasion and isolation), and additional socioeconomic factors. Explicit analysis with tools such as those we propose can help managers make

Climate-induced trends in predator–prey synchrony differ across life-history stages of an anadromous salmonid

Science.gov (United States)

Bell, Donovan A.; Kovach, Ryan; Vulstek, Scott C.; Joyce, John E.; Tallmon, David A.

2017-01-01

Differential climate-induced shifts in phenology can create mismatches between predators and prey, but few studies have examined predator–prey mismatch across multiple life-history stages. We used long-term data from a warming stream with shifting salmonid migration timings to quantify intra-annual migration synchrony between predatory Dolly Varden (Salvelinus malma) and Pacific salmon prey and examined how predator–prey synchrony has been influenced by climate change. We demonstrate that Dolly Varden have become increasingly mismatched with spring downstream migrations of abundant pink salmon (Oncorhynchus gorbuscha) juveniles. However, Dolly Varden have remained matched with fall upstream migrations of spawning Pacific salmon, including coho (Oncorhynchus kisutch), sockeye (Oncorhynchus nerka), and pink salmon. Downstream predator–prey migration synchrony decreased over time and with higher temperatures, particularly with pink salmon. In contrast, upstream migration synchrony was temporally stable and increased with rising temperatures. Differing trends in Dolly Varden predator–prey synchrony may be explained by the direct use of salmon to cue upstream migration, but not downstream migration. Overall, we show that climate change can have differing impacts on predator–prey synchrony across life-history stages.

Do benthic sediment characteristics explain the distribution of juveniles of the deposit-feeding sea cucumber Australostichopus mollis?

Science.gov (United States)

Slater, Matthew J.; Jeffs, Andrew G.

2010-10-01

Despite the economic importance of many deposit-feeding sea cucumbers, the ecology of their juveniles is poorly understood and factors influencing juvenile habitat selection remain largely unexplained. We investigated the importance of the characteristics of the available sediment in determining the highly localised distribution of juveniles of the deposit-feeding Australasian sea cucumber Australostichopus mollis. Wild-caught juveniles were displaced to non-juvenile habitats with surface sediments characterised by lower total organic content (TOM) and nitrogen content, higher chlorophyll- a content and coarser grain size profiles compared to juvenile sites. The growth of displaced individual animals was monitored over 9 months and compared to control animals caged in the juvenile habitats. Displaced juvenile sea cucumbers had high survival rates that did not differ significantly from juvenile habitats. Displaced juveniles exhibited significantly higher specific growth rate (SGR) than those at juvenile sites ( p < 0.001), although the growth of individuals was highly variable within individual cages and among sites. The lower TOM and nitrogen content, and coarser grain size profiles at non-juvenile sites did not result in reductions in juvenile survival or growth. Higher microphytobenthic activity may have resulted in the higher growth rates observed at shallow non-juvenile sites. The SGR of juveniles over the first 6 months of the experiment ranged between 0.45% d - 1 and 0.74% d - 1 for all sites. This was followed by marked growth limitation between 6 and 9 months either as a result of increasing juvenile biomass in cages or seasonal growth limitation. A subsequent reduction in juvenile density resulted in markedly increased growth over the following 3 month period. Juvenile A. mollis show an ability to exploit a variety of benthic sediment food sources, indicating that their highly localised distribution is not due to differences in the food quality of

Salmonids fish census, fish size, water temperature, and dissolved oxygen data collected from Lawrence Creek, Van Duzen River watershed, California from 2015-12-14 to 2016-03-24 (NCEI Accession 0148459)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Juvenile coho salmon seek slow velocity areas as rivers rise during storm events. Studies have shown significant increase in juvenile coho salmon growth and survival...

Ecology and impacts of nonnative salmonids with special reference to brook trout (Salvelinus fontinalis Mitchill) in North Europe

OpenAIRE

Korsu, K. (Kai)

2008-01-01

Abstract My main objectives in this thesis were to explore general patterns and mechanisms driving salmonid invasions globally and, more specifically, to examine the invasion dynamics and impacts of the North American brook trout in North European stream systems. Non-native salmonids have often spread extensively and caused many harmful impacts on their native counterparts. Among the three globally introduced salmonids, the European brown trout appeared as the 'worst' alien species (st...

Experimental Transmission of Frog Virus 3-Like Ranavirus in Juvenile Chelonians at Two Temperatures.

Science.gov (United States)

Allender, Matthew C; Barthel, Ashley C; Rayl, Jeremy M; Terio, Karen A

2018-06-07

The pathogenicity of frog virus 3 (FV3)-like ranavirus varies in adult chelonian species at different environmental temperatures, but differences in pathogenicity at different temperatures has yet to be determined in juveniles. Our objective was to determine the susceptibility to FV3-like ranavirus in four species of juvenile chelonians: red-eared sliders (RES; Trachemys scripta elegans), Mississippi map turtles ( Graptemys pseudogeographica kohnii), false map turtles (FMT; Graptemys pseudogeographica), and eastern river cooters ( Pseudemys concinna concinna) at two environmental temperatures. Two simultaneous trials ( n=8 treatment and n=4 controls of each species) were conducted in separate temperature-controlled rooms with animals maintained at 22 C or 27 C. All of the inoculated animals of each species at each temperature died, but no mortality was observed in control animals. Median survival times varied between 8 d and 11 d, based on species and temperature, with RES in the 27 C trial surviving the shortest time and the FMT in the 22 C trial surviving the longest. Combining all species, turtles in the 27 C trial survived for fewer days than those housed at 22 C, despite all turtles in both trials having similar viral copies detected in postmortem tissues. Lesions in inoculated turtles resembled those noted in natural and experimental FV3-like ranavirus infections and included vasculitis, thrombosis, hemorrhage in multiple organs, renal tubular necrosis, and hepatic necrosis. Myositis was not present in any juvenile, infected turtles in this study. This study confirmed that juvenile chelonians have a high susceptibility to ranaviral disease.

Evaluation of a recirculating pond system for rearing juvenile freshwater mussels at White Sulphur Springs National Fish Hatchery, West Virginia, U.S.A.

Science.gov (United States)

Mummert, A.; Newcomb, T.J.; Neves, R.J.; Parker, B.

2006-01-01

A recirculating double-pond system at White Sulphur Springs National Fish Hatchery in West Virginia, U.S.A., was evaluated for suitability for culturing juvenile freshwater mussels. Newly metamorphosed juveniles of Villosa iris and Lampsilis fasciola were placed in the system, and their growth and survival were evaluated for 94 days. Throughout the study, parameters of water quality remained within ranges suitable for mussel survival. Planktonic algal densities in the pond system ranged from 2850 to 6892 cells/ml. Thirty-seven algal taxa were identified, primarily green algae (Chlorophyta), diatoms (Bacillariophyceae), and blue-green algae (Cyanoprokaryota). Over the culture period, juveniles of L. fasciola experienced significantly lower (p fasciola may indicate a failure of the flow-through pond environment to meet its habitat requirements or that variable microhabitat conditions within culture containers existed. Growth did not differ significantly between the species (p = 0.13). Survival of V. iris and growth of both species were similar to previous trials to culture juvenile mussels. Survival rates as high as 66.4% at 93 days for V. iris suggest that juveniles of some riverine species can be successfully cultured in a recirculating pond environment.

Survival, growth and stress response of juvenile tidewater goby, Eucyclogobius newberryi, to interspecific competition for food

Science.gov (United States)

Chase, Daniel A; Flynn, Erin E; Todgham, Anne E

2016-01-01

Abstract Reintroduction of endangered fishes to historic habitat has been used as a recovery tool; however, these fish may face competition from other fishes that established in their native habitat since extirpation. This study investigated the physiological response of tidewater goby, Eucyclogobius newberryi, an endangered California fish, when competing for food with threespine stickleback, Gasterosteus aculeatus, a native species, and rainwater killifish, Lucania parva, a non-native species. Survival, growth and physiological indicators of stress (i.e. cortisol, glucose and lactate concentrations) were assessed for juvenile fish held for 28 days in two food-limited conditions. When fed a 75% ration, survival of E. newberryi was significantly lower when held with G. aculeatus. In all fish assemblages, weight and relative condition decreased then stabilized over the 28 day experiment, while length remained unchanged. Whole-body cortisol in E. newberryi was not affected by fish assemblage; however, glucose and lactate concentrations were significantly higher with conspecifics than with other fish assemblages. When fed a 50% ration, survival of E. newberryi decreased during the second half of the experiment, while weight and relative condition decreased and length remained unchanged in all three fish assemblages. Cortisol concentrations were significantly higher for all fish assemblages compared with concentrations at the start of the experiment, whereas glucose and lactate concentrations were depressed relative to concentrations at the start of the experiment, with the magnitude of decrease dependent on the species assemblage. Our findings indicate that E. newberryi exhibited reduced growth and an elevated generalized stress response during low food availability. In response to reduced food availability, competition with G. aculeatus had the greatest physiological effect on E. newberryi, with minimal effects from the non-native L. parva. This study presents

Fish embryo and juvenile size under hypoxia in the mouth- brooding African cichlid Pseudocrenilabrus multicolor

Directory of Open Access Journals (Sweden)

E.E. REARDON, L.J. CHAPMAN

2012-06-01

Full Text Available We used a field survey and a laboratory rearing experiment to (a examine response (size and survival to life-long hypoxia in offspring of the African maternal mouth-brooding cichlid Pseudocrenilabrus multicolor victoriae (Seegers and (b explore the degree to which developmental response can be environmentally-induced. Embryo size metrics were quantified in 9 field populations across a range of dissolved oxygen (DO concentrations. In the laboratory, first generation (F1 broods of low-DO origin were reared under high or low DO. Brooding period was quantified for the mothers; and egg size, egg metabolic rate and juvenile size-at-release were quantified in their (F2 offspring. The F2 offspring were split and grown for 3 months post-release under high or low DO, and juvenile size and survival were quantified. In the field survey, across stages, embryos from low-DO field populations were shorter and weighed less than embryos from high-DO populations. In the laboratory experiment, F2 eggs and juveniles-at-release from mother’s mouth did not differ in mass, length, survival regardless of development DO environment. However, juveniles diverged in size after leaving mother’s mouth, exhibiting smaller size when grown under low DO. Size differences in embryo size across field populations and divergence in embryo size after release from the mother’s mouth support predictions for smaller body size under hypoxia. There was no evidence for negative effects on survival of juveniles after 3 months. Brooding period was 16% shorter in females reared under low DO suggesting that hypoxia may accelerate embryo development. This work provides insights into how bearer fishes respond to hypoxic stress relative to fishes with no post-spawning parental care; a shorter brooding interval and smaller body size may provide an optimal solution to parent and embryo survival under hypoxia in brooding fishes [Current Zoology 58 (3: 401-412, 2012].

Early social networks predict survival in wild bottlenose dolphins.

Directory of Open Access Journals (Sweden)

Margaret A Stanton

Full Text Available A fundamental question concerning group-living species is what factors influence the evolution of sociality. Although several studies link adult social bonds to fitness, social patterns and relationships are often formed early in life and are also likely to have fitness consequences, particularly in species with lengthy developmental periods, extensive social learning, and early social bond-formation. In a longitudinal study of bottlenose dolphins (Tursiops sp., calf social network structure, specifically the metric eigenvector centrality, predicted juvenile survival in males. Additionally, male calves that died post-weaning had stronger ties to juvenile males than surviving male calves, suggesting that juvenile males impose fitness costs on their younger counterparts. Our study indicates that selection is acting on social traits early in life and highlights the need to examine the costs and benefits of social bonds during formative life history stages.

Effects of the proposed California WaterFix North Delta Diversion on survival of juvenile Chinook salmon (Oncorhynchus tshawytscha) in the Sacramento-San Joaquin River Delta, northern California

Science.gov (United States)

Perry, Russell W.; Pope, Adam C.

2018-05-11

The California Department of Water Resources and Bureau of Reclamation propose new water intake facilities on the Sacramento River in northern California that would convey some of the water for export to areas south of the Sacramento-San Joaquin River Delta (hereinafter referred to as the Delta) through tunnels rather than through the Delta. The collection of water intakes, tunnels, pumping facilities, associated structures, and proposed operations are collectively referred to as California WaterFix. The water intake facilities, hereinafter referred to as the North Delta Diversion (NDD), are proposed to be located on the Sacramento River downstream of the city of Sacramento and upstream of the first major river junction where Sutter Slough branches from the Sacramento River. The NDD can divert a maximum discharge of 9,000 cubic feet per second (ft3 /s) from the Sacramento River, which reduces the amount of Sacramento River inflow into the Delta. In this report, we conduct four analyses to investigate the effect of the NDD and its proposed operation on survival of juvenile Chinook salmon (Oncorhynchus tshawytscha). All analyses used the results of a Bayesian survival model that allowed us to simulate travel time, migration routing, and survival of juvenile Chinook salmon migrating through the Delta in response to NDD operations, which affected both inflows to the Delta and operation of the Delta Cross Channel (DCC). For the first analysis, we evaluated the effect of the NDD bypass rules on salmon survival. The NDD bypass rules are a set of operational rule curves designed to provide adaptive levels of fish protection by defining allowable diversion rates as a function of (1) Sacramento River discharge as measured at Freeport, and (2) time of year when endangered runs requiring the most protection are present. We determined that all bypass rule curves except constant low-level pumping (maximum diversion of 900 ft3 /s) could cause a sizeable decrease in survival by as

Underwater methods for study of salmonids in the Intermountain West

Science.gov (United States)

Russell F. Thurow

1994-01-01

This guide describes underwater methods using snorkeling gear to study fish populations in flowing waters of the Intermountain West. It outlines procedures for estimating salmonid abundance and habitat use and provides criteria for identifying and estimating the size of fish underwater.

Naive Juveniles Are More Likely to Become Breeders after Witnessing Predator Mobbing.

Science.gov (United States)

Griesser, Michael; Suzuki, Toshitaka N

2017-01-01

Responding appropriately during the first predatory attack in life is often critical for survival. In many social species, naive juveniles acquire this skill from conspecifics, but its fitness consequences remain virtually unknown. Here we experimentally demonstrate how naive juvenile Siberian jays (Perisoreus infaustus) derive a long-term fitness benefit from witnessing knowledgeable adults mobbing their principal predator, the goshawk (Accipiter gentilis). Siberian jays live in family groups of two to six individuals that also can include unrelated nonbreeders. Field observations showed that Siberian jays encounter predators only rarely, and, indeed, naive juveniles do not respond to predator models when on their own but do when observing other individuals mobbing them. Predator exposure experiments demonstrated that naive juveniles had a substantially higher first-winter survival after observing knowledgeable group members mobbing a goshawk model, increasing their likelihood of acquiring a breeding position later in life. Previous research showed that naive individuals may learn from others how to respond to predators, care for offspring, or choose mates, generally assuming that social learning has long-term fitness consequences without empirical evidence. Our results demonstrate a long-term fitness benefit of vertical social learning for naive individuals in the wild, emphasizing its evolutionary importance in animals, including humans.

Enhanced invertebrate prey production following estuarine restoration supports foraging for multiple species of juvenile salmonids (Oncorhynchus spp.)

Science.gov (United States)

Woo, Isa; Davis, Melanie; Ellings, Christopher S.; Nakai, Glynnis; Takekawa, John Y.; De La Cruz, Susan

2018-01-01

Estuaries provide crucial foraging resources and nursery habitat for threatened populations of anadromous salmon. As such, there has been a global undertaking to restore habitat and tidal processes in modified estuaries. The foraging capacity of these ecosystems to support various species of out-migrating juvenile salmon can be quantified by monitoring benthic, terrestrial, and pelagic invertebrate prey communities. Here, we present notable trends in the availability of invertebrate prey at several sites within a restoring large river delta in Puget Sound, Washington, U.S.A. Three years after the system was returned to tidal influence, we observed substantial additions to amphipod, copepod, and cumacean abundances in newly accessible marsh channels (from 0 to roughly 5,000–75,000 individuals/m2). In the restoration area, terrestrial invertebrate colonization was dependent upon vegetative cover, with dipteran and hymenopteran biomass increasing 3-fold between 1 and 3 years post-restoration. While the overall biodiversity within the restoration area was lower than in the reference marsh, estimated biomass was comparable to or greater than that found within the other study sites. This additional prey biomass likely provided foraging benefits for juvenile Chinook, chum, and coho salmon. Primary physical drivers differed for benthic, terrestrial, and pelagic invertebrates, and these invertebrate communities are expected to respond differentially depending on organic matter exchange and vegetative colonization. Restoring estuaries may take decades to meet certain success criteria, but our study demonstrates rapid enhancements in foraging resources understood to be used for estuary-dependent wildlife.

Growth, food consumption, and energy status of juvenile pallid sturgeon fed natural or artificial diets

Science.gov (United States)

Meyer, Hilary A.; Chipps, Steven R.; Graeb, Brian D. S.; Klumb, Robert A.

2016-01-01

Stocking of hatchery-raised fish is an important part of the pallid sturgeon Scaphirhynchus albus recovery program. In the wild, juvenile pallid sturgeon consume primarily aquatic insects, although little is known about specific dietary needs. In hatchery settings, pallid sturgeon are fed commercial diets that are formulated for salmonids. To compare food consumption, growth, and energy status of pallid sturgeon fed artificial or natural diets, we conducted a laboratory study using 24 juvenile pallid sturgeon (initial fork length 153–236 mm). Pallid sturgeon were fed a daily ration of either commercial pellets (1 mm, slow sinking; 45% protein, 19% fat) or chironomid larvae for 5 wk. Natural-fed pallid sturgeon exhibited a greater specific growth rate (2.12% d−1) than pellet-fed fish (0.06% d−1). Similarly, relative condition was greater for natural-fed sturgeon (Kn = 1.11) than that observed for pellet-fed fish (Kn = 0.87). In contrast, the hepatosomatic index was significantly higher in pellet-fed fish (2.5%), indicating a high lipid diet compared with natural-fed sturgeon (1.4%). Given the importance of natural diets to fish digestion and growth, it is suggested that a more holistic approach be applied in the development of a practical diet for pallid sturgeon that incorporates attributes of natural prey.

Comparative sensitivity of juvenile and adult Potamopyrgus antipodarum (Mollusca: Hydrobiidae) under chronic exposure to cadmium and tributyltin.

Science.gov (United States)

Ruppert, Katharina; Geiß, Cornelia; Ostermann, Sina; Theis, Christina; Oehlmann, Jörg

2016-07-28

To investigate a potential extension of a partial life cycle test protocol to a full life cycle test design, a comparative sensitivity analysis with juvenile and adult Potamopyrgus antipodarum was performed. Neonates and adult snails were exposed to the metal cadmium (Cd) and the endocrine disruptor tributyltin (TBT) at nominal concentrations ranging from 1.56 to 50 μg Cd/L and from 25 to 1,000 ng TBT-Sn/L. The experiments were performed over 28 days at 16°C in a semi-static test design. Mortality was assessed for both life stages. Juvenile snails' specific growth rate and reproduction of adults were investigated as main endpoints. We determined effects on snails' survival, juvenile growth and embryo numbers in the brood pouch of adult snails under exposure to both chemicals. Juvenile control mortality was between 25% and 30% and significantly higher than in the control groups with adult snails. A higher sensitivity of juvenile snails compared to adults was observed for the endpoint mortality. Calculated LC50 in Cd exposed snails was 38.2 μg/L for adults and 15.0 μg/L for juvenile snails. Significant effects on mortality in TBT exposed adult snails occurred at the highest test concentration only with a LC50 of 535 ng Sn/L. Juvenile survival was significantly affected at 50.8 ng Sn/L and higher concentrations. Effect concentrations for the main endpoints reproduction and juvenile growth show comparable sensitivities. For Cd exposed groups, EC50 values were 11.3 μg/L for the endpoint reproduction in adult snails and 3.82 μg/L for juvenile growth with overlapping confidence intervals. TBT also significantly affected juvenile snails' growth (EC50: 178 ng Sn /L). EC50 for embryo numbers was 125 ng TBT-Sn/L. Results indicate the manageability of a FLC test starting with newly hatched snails. Precautions have to be taken to guarantee a sufficient number of surviving snails until adulthood so that reproduction can be assessed. For final decision for the

Diversity of Flavobacterium psychrophilum and the potential use of its phages for protection against bacterial cold water disease in salmonids

DEFF Research Database (Denmark)

Castillo, D.; Higuera, G.; Villa, M.

2012-01-01

Flavobacterium psychrophilum causes rainbow trout fry syndrome (RTFS) and cold water disease (CWD) in salmonid aquaculture. We report characterization of F. psychrophilum strains and their bacteriophages isolated in Chilean salmonid aquaculture. Results suggest that under laboratory conditions ph...... together with the bacteria in a ratio of 10 plaque‐forming units per colony‐forming unit. While we recognize the artificial laboratory conditions used for these protection assays, this work is the first to demonstrate that phages might be able protect salmonids from RTFS or CWD....

Timing of natal nests is an important factor affecting return rates of juvenile Great Reed Warblers

Czech Academy of Sciences Publication Activity Database

Sosnovcová, Kateřina; Koleček, Jaroslav; Požgayová, Milica; Jelínek, Václav; Šulc, Michal; Steidlová, Petra; Honza, Marcel; Procházka, Petr

2018-01-01

Roč. 159, č. 1 (2018), s. 183-190 ISSN 0021-8375 R&D Projects: GA ČR GA13-06451S Institutional support: RVO:68081766 Keywords : Acrocephalus arundinaceus * Juvenile condition * Juvenile survival * Local dispersal distances * Natal philopatry Subject RIV: EG - Zoology OBOR OECD: Ornithology Impact factor: 1.468, year: 2016

Predicting recolonization patterns and interactions between potamodromous and anadromous salmonids in response to dam removal in the Elwha River, Washington State, USA

Science.gov (United States)

Brenkman, S.J.; Pess, G.R.; Torgersen, C.E.; Kloehn, K.K.; Duda, J.J.; Corbett, S.C.

2008-01-01

The restoration of salmonids in the Elwha River following dam removal will cause interactions between anadromous and potamodromous forms as recolonization occurs in upstream and downstream directions. Anadromous salmonids are expected to recolonize historic habitats, and rainbow trout (Oncorhynchus mykiss) and bull trout (Salvelinus confluentus) isolated above the dams for 90 years are expected to reestablish anadromy. We summarized the distribution and abundance of potamodromous salmonids, determined locations of spawning areas, and mapped natural barriers to fish migration at the watershed scale based on data collected from 1993 to 2006. Rainbow trout were far more abundant than bull trout throughout the watershed and both species were distributed up to river km 71. Spawning locations for bull trout and rainbow trout occurred in areas where we anticipate returning anadromous fish to spawn. Nonnative brook trout were confined to areas between and below the dams, and seasonal velocity barriers are expected to prevent their upstream movements. We hypothesize that the extent of interaction between potamodromous and anadromous salmonids will vary spatially due to natural barriers that will limit upstream-directed recolonization for some species of salmonids. Consequently, most competitive interactions will occur in the main stem and floodplain downstream of river km 25 and in larger tributaries. Understanding future responses of Pacific salmonids after dam removal in the Elwha River depends upon an understanding of existing conditions of the salmonid community upstream of the dams prior to dam removal.

A Quantitative Polymerase Chain Reaction Assay for the Detection and Quantification of Epizootic Epitheliotropic Disease Virus (EEDV; Salmonid Herpesvirus 3).

Science.gov (United States)

Glenney, Gavin W; Barbash, Patricia A; Coll, John A

2016-03-01

Epizootic epitheliotropic disease virus (EEDV; salmonid herpesvirus [SalHV3]; family Alloherpesviridae) causes a systemic disease of juvenile and yearling Lake Trout Salvelinus namaycush. No cell lines are currently available for the culture and propagation of EEDV, so primary diagnosis is limited to PCR and electron microscopy. To better understand the pervasiveness of EEDV (carrier or latent state of infection) in domesticated and wild Lake Trout populations, we developed a sensitive TaqMan quantitative PCR (qPCR) assay to detect the presence of the EEDV terminase gene in Lake Trout tissues. This assay was able to detect a linear standard curve over nine logs of plasmid dilution and was sensitive enough to detect single-digit copies of EEDV. The efficiency of the PCR assay was 99.4 ± 0.06% (mean ± SD), with a 95% confidence limit of 0.0296 (R(2) = 0.994). Methods were successfully applied to collect preliminary data from a number of species and water bodies in the states of Pennsylvania, New York, and Vermont, indicating that EEDV is more common in wild fish than previously known. In addition, through the development of this qPCR assay, we detected EEDV in a new salmonid species, the Cisco Coregonus artedi. The qPCR assay was unexpectedly able to detect two additional herpesviruses, the Atlantic Salmon papillomatosis virus (ASPV; SalHV4) and the Namaycush herpesvirus (NamHV; SalHV5), which both share high sequence identity with the EEDV terminase gene. With these unexpected findings, we subsequently designed three primer sets to confirm initial TaqMan qPCR assay positives and to differentiate among EEDV, ASPV, and NamHV by detecting the glycoprotein genes via SYBR Green qPCR. Received April 20, 2015; accepted November 10, 2015.

NIS occurrence - Non-native species impacts on threatened and endangered salmonids

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The objectives of this project: a) Identify the distribution of non-natives in the Columbia River Basin b) Highlight the impacts of non-natives on salmonids c)...

Effects of feeding frequency on growth, survival rate and body composition in sea bass (Lates calcarifer) juveniles fed a commercial diet under laboratory condition

OpenAIRE

Erlinda S. Ganzon-Naret

2013-01-01

A 60 day feeding trial was conducted to investigate the effects of different feeding frequencies on the growth, survival rate and body composition of sea bass (Lates calcarifer) juveniles fed commercial diet, reared under laboratory condition. The average initial weight of fish was 4.59 g and its initial total length of 7.11 cm was determined for the conditions factors. Ten fish were stocked in each 12 - 100 L conical fiberglass tanks filled with 90 L seawater at three replicates ...

Surgical implantation techniques for electronic tags in fish

Energy Technology Data Exchange (ETDEWEB)

Wagner, Glenn N.; Cooke, Steven J.; Brown, Richard S.; Deters, Katherine A.

2011-01-01

Intracoelomic implantation of transmitters into fish requires making a surgical incision, incision closure, and other surgery related techniques; however, the tools and techniques used in the surgical process vary widely. We review the available literature and focus on tools and techniques used for conducting surgery on juvenile salmonids because of the large amount of research that is conducted on them. The use of sterilized surgical instruments properly selected for a given size of fish will minimize tissue damage and infection rates, and speed the wound healing of fish implanted with transmitters. For the implantation of transmitters into small fish, the optimal surgical methods include making an incision on the ventral midline along the linea alba (for studies under 1 month), protecting the viscera (by lifting the skin with forceps while creating the incision), and using absorbable monofilament suture with a small-swaged-on swaged-on tapered or reverse-cutting needle. Standardizing the implantation techniques to be used in a study involving particular species and age classes of fish will improve survival and transmitter retention while allowing for comparisons to be made among studies and across multiple years. This review should be useful for researchers working on juvenile salmonids and other sizes and species of fish.

How do land-based salmonid farms affect stream ecology?

International Nuclear Information System (INIS)

Tello, A.; Corner, R.A.; Telfer, T.C.

2010-01-01

Increasing research is highlighting the fact that streams provide crucial ecosystem services through the biogeochemical and ecological processes they sustain. Freshwater land-based salmonid farms commonly discharge their effluents into low order, headwater streams, partly due to the fact that adequate freshwater resources for production are commonly found in undisturbed areas. We review the effects of salmonid farm effluents on different biological components of stream ecosystems. Relevant considerations related to the temporal and spatial scales of effluent discharge and ecological effects are discussed. These highlight the need to characterize the patterns of stressor discharge when assessing environmental impacts and designing ecological effects studies. The potential role of multiple stressors in disrupting ecosystem structure and function is discussed with an emphasis on aquaculture veterinary medicines. Further research on the effects of veterinary medicines using relevant exposure scenarios would significantly contribute to our understanding of their impact in relation to other effluent stressors. - This article reviews the effects of aquaculture effluents on stream ecosystems with an emphasis on veterinary medicines and the temporal patterns of effluent discharge.

Effects of fine sediment, hyporheic flow, and spawning site characteristics on survival and development of bull trout embryos

Science.gov (United States)

Bowerman, Tracy; Neilson, Bethany; Budy, Phaedra

2014-01-01

Successful spawning is imperative for the persistence of salmonid populations, but relatively little research has been conducted to evaluate factors affecting early life-stage survival for bull trout (Salvelinus confluentus), a threatened char. We conducted a field experiment to assess the relationship between site-specific environmental factors and bull trout embryo survival and fry emergence timing. Survival from egg to hatch was negatively related to percent fine sediment (construction and selection of spawning sites with strong downwelling appear to enhance hyporheic flow rates and bull trout egg survival, but early life-stage success may ultimately be limited by intrusion of fine sediment into the incubation environment.

Real-life 10-year retention rate of first-line anti-TNF drugs for inflammatory arthritides in adult- and juvenile-onset populations: similarities and differences.

Science.gov (United States)

Favalli, Ennio Giulio; Pontikaki, Irene; Becciolini, Andrea; Biggioggero, Martina; Ughi, Nicola; Romano, Micol; Crotti, Chiara; Gattinara, Maurizio; Gerloni, Valeria; Marchesoni, Antonio; Meroni, Pier Luigi

2017-08-01

The aim of this study is to retrospectively analyze 10-year drug survival of first-line TNF inhibitor (TNFi) in rheumatoid arthritis (RA), ankylosing spondylitis (AS), psoriatic arthritis (PsA), and juvenile idiopathic arthritis (JIA) patients, comparing withdrawal rates and discontinuation pattern between adult- and juvenile-onset populations. RA, AS, PsA, and JIA patients treated with infliximab, etanercept, or adalimumab as first TNFi between 1999 and 2015 were extracted from a local registry. Drug survival up to 10-year follow-up was evaluated by the Kaplan-Meier method and compared according to age (adult vs juvenile onset), TNFi agent, and discontinuation reason by a stratified log-rank test. Three hundred sixty JIA (205 etanercept, 66 adalimumab, and 89 infliximab) and 951 (607 RA, 188 AS, and 156 PsA) adult patients (464 infliximab, 262 adalimumab, and 225 etanercept) were included. After exclusion of systemic-onset JIA (18.5%), overall 10-year retention rate was 31.8%, with no difference between adult- and juvenile-onset patients (32.1 and 30.2%, respectively; HR 0.938 [95% CI 0.782-1.125]). Etanercept showed the highest drug survival in adult-onset population (p adult population (29.75%) with a significantly higher risk of discontinuation than in juvenile-onset subgroup (HR 1.390 [95% CI 1.060-1.824]). Serious infections and malignancies caused TNFi withdrawal only in adult whereas gastrointestinal, neuropsychiatric, and ocular complications quite only in juvenile patients. Despite a similar 10-year drug survival, adult- and juvenile-onset subpopulations showed a significantly different pattern of TNFi reasons for discontinuation.

Inter-annual variability in apparent relative production, survival, and growth of juvenile Lost River and shortnose suckers in Upper Klamath Lake, Oregon, 2001–15

Science.gov (United States)

Burdick, Summer M.; Martin, Barbara A.

2017-06-15

Executive SummaryPopulations of the once abundant Lost River (Deltistes luxatus) and shortnose suckers (Chasmistes brevirostris) of the Upper Klamath Basin, decreased so substantially throughout the 20th century that they were listed under the Endangered Species Act in 1988. Major landscape alterations, deterioration of water quality, and competition with and predation by exotic species are listed as primary causes of the decreases in populations. Upper Klamath Lake populations are decreasing because fish lost due to adult mortality, which is relatively low for adult Lost River suckers and variable for adult shortnose suckers, are not replaced by new young adult suckers recruiting into known adult spawning aggregations. Catch-at-age and size data indicate that most adult suckers presently in Upper Klamath Lake spawning populations were hatched around 1991. While, a lack of egg production and emigration of young fish (especially larvae) may contribute, catch-at-length and age data indicate high mortality during the first summer or winter of life may be the primary limitation to the recruitment of young adults. The causes of juvenile sucker mortality are unknown.We compiled and analyzed catch, length, age, and species data on juvenile suckers from Upper Klamath Lake from eight prior studies conducted from 2001 to 2015 to examine annual variation in apparent production, survival, and growth of young suckers. We used a combination of qualitative assessments, general linear models, and linear regression to make inferences about annual differences in juvenile sucker dynamics. The intent of this exercise is to provide information that can be compared to annual variability in environmental conditions with the hopes of understanding what drives juvenile sucker population dynamics.Age-0 Lost River suckers generally grew faster than age-0 shortnose suckers, but the difference in growth rates between the two species varied among years. This unsynchronized annual variation in

Growth of juvenile steelhead Oncorhynchus mykiss under size-selective pressure limited by seasonal bioenergetic and environmental constraints

Science.gov (United States)

Thompson, Jamie N.; Beauchamp, David A.

2016-01-01

Increased freshwater growth of juvenile steelhead Oncorhynchus mykiss improved survival to smolt and adult stages, thus prompting an examination of factors affecting growth during critical periods that influenced survival through subsequent life stages. For three tributaries with contrasting thermal regimes, a bioenergetics model was used to evaluate how feeding rate and energy density of prey influenced seasonal growth and stage-specific survival of juvenile O. mykiss. Sensitivity analysis examined target levels for feeding rate and energy density of prey during the growing season that improved survival to the smolt and adult stages in each tributary. Simulated daily growth was greatest during warmer months (1 July to 30 September), whereas substantial body mass was lost during cooler months (1 December to 31 March). Incremental increases in annual feeding rate or energy density of prey during summer broadened the temperature range at which faster growth occurred and increased the growth of the average juvenile to match those that survived to smolt and adult stages. Survival to later life stages could be improved by increasing feeding rate or energy density of the diet during summer months, when warmer water temperatures accommodated increased growth potential. Higher growth during the summer period in each tributary could improve resiliency during subsequent colder periods that lead to metabolic stress and weight loss. As growth and corresponding survival rates in fresh water are altered by shifting abiotic regimes, it will be increasingly important for fisheries managers to better understand the mechanisms affecting growth limitations in rearing habitats and what measures might maintain or improve growth conditions and survival.

Spatial distribution of the stomach weights of juvenile anchovy (Engraulis encrasicolus L.) in the Bay of Biscay

KAUST Repository

Bachiller, Eneko

2012-11-28

Previous studies have shown that the survival of larval and juvenile anchovy off the continental shelf in the Bay of Biscay is not significantly different from that observed on the shelf, even though the food concentration is significantly higher on the shelf. In this paper we investigate the causes for the lack of relationship between food and survival for anchovy juvenile through analyses of feeding activity versus zooplankton distribution (in the transition from summer to fall from 2003 to 2010). The spatial distribution of the stomach weights of juvenile anchovy in relation to body size on and off the shelf revealed higher stomach fullness in areas off the shelf, where less zooplankton biomass was available. This result indicates that the food concentration is not always the main factor determining ingestion in fish. A situation of comparatively lesser prey abundance may provide better feeding conditions when combined with lower predation risk and lower light attenuation. In addition, the relatively heavier stomachs found in anchovies caught in years of higher recruitment indices suggest a large stomach content may be a symptom of good biological condition that may favour the winter survival of a larger fraction of the juvenile stock. © 2012 International Council for the Exploration of the Sea.

Effects of ocean warming and acidification on survival, growth and skeletal development in the early benthic juvenile sea urchin (Heliocidaris erythrogramma).

Science.gov (United States)

Wolfe, Kennedy; Dworjanyn, Symon A; Byrne, Maria

2013-09-01

Co-occurring ocean warming, acidification and reduced carbonate mineral saturation have significant impacts on marine biota, especially calcifying organisms. The effects of these stressors on development and calcification in newly metamorphosed juveniles (ca. 0.5 mm test diameter) of the intertidal sea urchin Heliocidaris erythrogramma, an ecologically important species in temperate Australia, were investigated in context with present and projected future conditions. Habitat temperature and pH/pCO2 were documented to place experiments in a biologically and ecologically relevant context. These parameters fluctuated diurnally up to 10 °C and 0.45 pH units. The juveniles were exposed to three temperature (21, 23 and 25 °C) and four pH (8.1, 7.8, 7.6 and 7.4) treatments in all combinations, representing ambient sea surface conditions (21 °C, pH 8.1; pCO2 397; ΩCa 4.7; ΩAr 3.1), near-future projected change (+2-4 °C, -0.3-0.5 pH units; pCO2 400-1820; ΩCa 5.0-1.6; ΩAr 3.3-1.1), and extreme conditions experienced at low tide (+4 °C, -0.3-0.7 pH units; pCO2 2850-2967; ΩCa 1.1-1.0; ΩAr 0.7-0.6). The lowest pH treatment (pH 7.4) was used to assess tolerance levels. Juvenile survival and test growth were resilient to current and near-future warming and acidification. Spine development, however, was negatively affected by near-future increased temperature (+2-4 °C) and extreme acidification (pH 7.4), with a complex interaction between stressors. Near-future warming was the more significant stressor. Spine tips were dissolved in the pH 7.4 treatments. Adaptation to fluctuating temperature-pH conditions in the intertidal may convey resilience to juvenile H. erythrogramma to changing ocean conditions, however, ocean warming and acidification may shift baseline intertidal temperature and pH/pCO2 to levels that exceed tolerance limits. © 2013 John Wiley & Sons Ltd.

Survival and metamorphosis of low-density populations of larval sea lampreys (Petromyzon marinus) in streams following lampricide treatment

Science.gov (United States)

Johnson, Nicholas S.; Swink, William D.; Brenden, Travis O.; Slade, Jeffrey W.; Steeves, Todd B.; Fodale, Michael F.; Jones, Michael L.

2014-01-01

Sea lamprey Petromyzon marinus control in the Great Lakes primarily involves application of lampricides to streams where larval production occurs to kill larvae prior to their metamorphosing and entering the lakes as parasites (juveniles). Because lampricides are not 100% effective, larvae that survive treatment maymetamorphose before streams are again treated. Larvae that survive treatment have not beenwidely studied, so their dynamics are notwell understood.Wetagged and released larvae in six Great Lake tributaries following lampricide treatment and estimated vital demographic rates using multistate tag-recovery models. Model-averaged larval survivals ranged from 56.8 to 57.6%. Model-averaged adult recovery rates, which were the product of juvenile survivals and adult capture probabilities, ranged from 6.8 to 9.3%. Using stochastic simulations, we estimated production of juvenile sea lampreys from a hypothetical population of treatment survivors under different growth conditions based on parameter estimates from this research. For fast-growing populations, juvenile production peaked 2 years after treatment. For slow-growing populations, juvenile production was approximately one-third that of fast-growing populations,with production not peaking until 4 years after treatment. Our results suggest that dynamics (i.e., survival, metamorphosis) of residual larval populations are very similar to those of untreated larval populations. Consequently, residual populations do not necessarily warrant special consideration for the purpose of sea lamprey control and can be ranked for treatment along with other populations. Consecutive lampricide treatments, which are under evaluation by the sea lamprey control program, would bemost effective for reducing juvenile production in large, fast-growing populations.

Comparison of the movement and recapture of salmonid fishes tagged at two power plants

International Nuclear Information System (INIS)

Romberg, G.P.; Thommes, M.M.

1974-01-01

Fish tagging studies were conducted in the vicinity of Point Beach Nuclear Plant and Waukegan Power Plant to determine whether there were any seasonal or site specific differences in the residence behavior of salmonids at thermal discharges. Results showed that there were differences in the abundance and time of peak abundance of trout and salmon at the two power plant discharges. Certain species reacted differently to the two discharges probably as a result of maturity and water temperature. Salmonids did not appear to remain at either discharge for long periods. Direction of migration was affected by stocking location and water temperature

Simulated Impacts of Juvenile Mortality on Gulf of Mexico Sturgeon Populations

Directory of Open Access Journals (Sweden)

William B. Tate

2002-01-01

Full Text Available We used an age-structured computer model to assess the impact of changes in juvenile mortality on the Gulf of Mexico sturgeon population in the Suwannee River, Florida. We simulated population trends under four levels of annual juvenile mortality (20, 25, 30, and 35%. As the rate of mortality increased, population size decreased, and rates of population growth shifted from positive to negative. Our models indicated that juvenile survival is important to the success of gulf sturgeon populations, and mortality estimates are needed to predict population viability. We suggest that life history studies in estuaries should be conducted, and bycatch rates for commercial fisheries should be quantified to aid in the management and conservation of gulf sturgeon.

SPATACSIN mutations cause autosomal recessive juvenile amyotrophic lateral sclerosis.

Science.gov (United States)

Orlacchio, Antonio; Babalini, Carla; Borreca, Antonella; Patrono, Clarice; Massa, Roberto; Basaran, Sarenur; Munhoz, Renato P; Rogaeva, Ekaterina A; St George-Hyslop, Peter H; Bernardi, Giorgio; Kawarai, Toshitaka

2010-02-01

The mutation of the spatacsin gene is the single most common cause of autosomal recessive hereditary spastic paraplegia with thin corpus callosum. Common clinical, pathological and genetic features between amyotrophic lateral sclerosis and hereditary spastic paraplegia motivated us to investigate 25 families with autosomal recessive juvenile amyotrophic lateral sclerosis and long-term survival for mutations in the spatascin gene. The inclusion criterion was a diagnosis of clinically definite amyotrophic lateral sclerosis according to the revised El Escorial criteria. The exclusion criterion was a diagnosis of hereditary spastic paraplegia with thin corpus callosum in line with an established protocol. Additional pathological and genetic evaluations were also performed. Surprisingly, 12 sequence alterations in the spatacsin gene (one of which is novel, IVS30 + 1 G > A) were identified in 10 unrelated pedigrees with autosomal recessive juvenile amyotrophic lateral sclerosis and long-term survival. The countries of origin of these families were Italy, Brazil, Canada, Japan and Turkey. The variants seemed to be pathogenic since they co-segregated with the disease in all pedigrees, were absent in controls and were associated with amyotrophic lateral sclerosis neuropathology in one member of one of these families for whom central nervous system tissue was available. Our study indicates that mutations in the spatascin gene could cause a much wider spectrum of clinical features than previously recognized, including autosomal recessive juvenile amyotrophic lateral sclerosis.

Crims Island-Restoration and monitoring of juvenile salmon rearing habitat in the Columbia River Estuary, Oregon, 2004-10

Science.gov (United States)

Haskell, Craig A.; Tiffan, Kenneth F.

2011-01-01

-channel' was extended westward and connected to Bradbury Slough to create a second outlet to the main river. New intertidal channels were constructed from the existing 'T-channel' and tidal mudflats became inundated at high tide to increase rearing habitat for juvenile salmonids. The restoration action resulted in a 95-percent increase in available juvenile salmon rearing habitat. We collected juvenile salmon and other fishes at Crims Island and a nearby reference site using beach seines and fyke nets annually from March through August during all years. Benthic invertebrates were collected with sediment corers and drift invertebrates were collected with neuston nets. Juvenile salmon stomach contents were sampled using lavage. Vegetation and sediments characteristics were surveyed and we conducted a topographic/bathymetric survey using a RTK (real time kinematic) GPS (global positioning system). The fish assemblage at Crims Island, composed primarily of threespine stickleback (Gasterosteus aculeatus), non-native banded killifish (Fundulus diaphanus), peamouth chub (Mylocheilus caurinus), subyearling Chinook salmon (Oncorhynchus tshawytscha) (hereinafter referred to as subyearlings), and small numbers of juvenile chum salmon (Oncorhynchus keta), did not differ appreciably pre- and post-restoration. Subyearlings were the primary salmonid collected and were seasonally abundant from April through May during all years. The abundance of juvenile salmon declined seasonally as water temperature exceeded 20 degrees C in the Reference site by mid-June; however, subyearlings persisted at the Mainstem site and in subtidal channels of the Restoration site through the summer in water temperatures exceeding 22 degrees C. Residence times of subyearlings in Crims Island backwaters generally were short consisting of one or two tidal cycles. Median residence time was longer in the Restoration site than in the Reference site pre- and post-restoration. Small (mean = 55.7 millimeters) subyea

Spatial and temporal distribution of bull trout (Salvelinus confluentus)-size fish near the floating surface collector in the North Fork Reservoir, Oregon, 2016

Science.gov (United States)

Adams, Noah S.; Smith, Collin D.

2017-06-26

Acoustic cameras were used to assess the behavior and abundance of bull trout (Salvelinus confluentus)-size fish at the entrance to the North Fork Reservoir juvenile fish floating surface collector (FSC). The purpose of the FSC is to collect downriver migrating juvenile salmonids at the North Fork Dam, and safely route them around the hydroelectric projects. The objective of the acoustic camera component of this study was to assess the behaviors of bull trout-size fish observed near the FSC, and to determine if the presence of bull trout-size fish influenced the collection or abundance of juvenile salmonids. Acoustic cameras were deployed near the surface and floor of the entrance to the FSC. The acoustic camera technology was an informative tool for assessing abundance and spatial and temporal behaviors of bull trout-size fish near the entrance of the FSC. Bull trout-size fish were regularly observed near the entrance, with greater abundances on the deep camera than on the shallow camera. Additionally, greater abundances were observed during the hours of sunlight than were observed during the night. Behavioral differences also were observed at the two depths, with surface fish traveling faster and straighter with more directed movement, and fish observed on the deep camera generally showing more milling behavior. Modeling potential predator-prey interactions and influences using collected passive integrated transponder (PIT) -tagged juvenile salmonids proved largely unpredictable, although these fish provided relevant timing and collection information. Overall, the results indicate that bull trout-size fish are present near the entrance of the FSC, concomitant with juvenile salmonids, and their abundances and behaviors indicate that they may be drawn to the entrance of the FSC because of the abundance of prey-sized fish.

Effects of Prior Experience on Shelter-Seeking Behavior of Juvenile American Lobsters.

Science.gov (United States)

Bayer, Skylar R; Bianchi, Katherine M; Atema, Jelle; Jacobs, Molly W

2017-04-01

Shelter-seeking behaviors are vital for survival for a range of juvenile benthic organisms. These behaviors may be innate or they may be affected by prior experience. After hatching, American lobsters Homarus americanus likely first come into contact with shelter during the late postlarval (decapodid) stage, known as stage IV. After the subsequent molt to the first juvenile stage (stage V), they are entirely benthic and are thought to be highly cryptic. We hypothesized that postlarval (stage IV) experience with shelter would carry over into the first juvenile stage (stage V) and reduce the time needed for juveniles to locate and enter shelters (sheltering). We found some evidence of a carryover effect, but not the one we predicted: stage V juveniles with postlarval shelter experience took significantly longer to initiate sheltering. We also hypothesized that stage V juveniles would demonstrate learning by relocating shelters more quickly with immediate prior experience. Our findings were mixed. In a maze, juveniles with immediate prior experience were faster to regain visual contact with shelter, suggesting that they had learned the location of the shelter. In contrast, there was no significant effect of immediate prior experience on time to initiate sheltering in an open arena, or in the maze after juveniles had regained visual contact. We conclude that very young (stage V) juvenile lobsters modify their shelter-seeking behavior based on prior experiences across several timescales. Ecologically relevant variation in habitat exposure among postlarval and early juvenile lobsters may influence successful recruitment in this culturally and commercially important fishery species.

Do environmental changes or juvenile competition act as mechanisms of species displacement in crayfishes?

Science.gov (United States)

Westhoff, Jacob T.; DiStefano, R.J.; Magoulick, D.D.

2012-01-01

The Big Creek Crayfish, Orconectes peruncus, is native to the St. Francis River drainage in Missouri, USA and is often absent where the introduced Woodland Crayfish, Orconectes hylas, has established. We performed a field experiment to determine whether effects of current abiotic conditions and interspecific competition with O. hylas were responsible for displacement of O. peruncus from parts of their former range. We examined growth and survival of juvenile male O. peruncus exposed to juvenile male O. hylas in enclosures at two sites in the former range of O. peruncus. Enclosures contained 8 (low density) or 16 individuals (high density) and had O. peruncus only (control) or both species (interspecific treatment). Juvenile O. peruncus were able to survive and grow in portions of their former range, implicating biotic versus abiotic factors in the displacement of O. peruncus. Survival rates of O. peruncus did not differ among treatments at either site. Orconectes peruncus showed significant growth in all treatments and interspecific effects were not greater than intraspecific effects on O. peruncus growth rates. High-density treatments showed significantly reduced O. peruncus growth rates compared to low-density treatments, except in Carver Creek interspecific treatments. When considered in the context of previous studies examining the effects of O. hylas on O. peruncus, results suggest that neither direct competition between juvenile males of the two species or abiotic change are responsible for the decreased range of O. peruncus. Additional research is required to determine the mechanism(s) driving the displacement of O. peruncus. ?? 2011 Springer Science+Business Media B.V.

Salmonid Chromosome Evolution as Revealed by a Novel Method for Comparing RADseq Linkage Maps

Science.gov (United States)

Gosselin, Thierry; Normandeau, Eric; Lamothe, Manuel; Isabel, Nathalie; Audet, Céline; Bernatchez, Louis

2016-01-01

Whole genome duplication (WGD) can provide material for evolutionary innovation. Family Salmonidae is ideal for studying the effects of WGD as the ancestral salmonid underwent WGD relatively recently, ∼65 Ma, then rediploidized and diversified. Extensive synteny between homologous chromosome arms occurs in extant salmonids, but each species has both conserved and unique chromosome arm fusions and fissions. Assembly of large, outbred eukaryotic genomes can be difficult, but structural rearrangements within such taxa can be investigated using linkage maps. RAD sequencing provides unprecedented ability to generate high-density linkage maps for nonmodel species, but can result in low numbers of homologous markers between species due to phylogenetic distance or differences in library preparation. Here, we generate a high-density linkage map (3,826 markers) for the Salvelinus genera (Brook Charr S. fontinalis), and then identify corresponding chromosome arms among the other available salmonid high-density linkage maps, including six species of Oncorhynchus, and one species for each of Salmo, Coregonus, and the nonduplicated sister group for the salmonids, Northern Pike Esox lucius for identifying post-duplicated homeologs. To facilitate this process, we developed MapComp to identify identical and proximate (i.e. nearby) markers between linkage maps using a reference genome of a related species as an intermediate, increasing the number of comparable markers between linkage maps by 5-fold. This enabled a characterization of the most likely history of retained chromosomal rearrangements post-WGD, and several conserved chromosomal inversions. Analyses of RADseq-based linkage maps from other taxa will also benefit from MapComp, available at: https://github.com/enormandeau/mapcomp/ PMID:28173098

Juvenile angiofibroma

Science.gov (United States)

Nasal tumor; Angiofibroma - juvenile; Benign nasal tumor; Juvenile nasal angiofibroma; JNA ... Juvenile angiofibroma is not very common. It is most often found in adolescent boys. The tumor contains many blood ...

An extremely sensitive nested PCR-RFLP mitochondrial marker for detection and identification of salmonids in eDNA from water samples

Directory of Open Access Journals (Sweden)

Laura Clusa

2017-02-01

Full Text Available Background Salmonids are native from the North Hemisphere but have been introduced for aquaculture and sport fishing in the South Hemisphere and inhabit most rivers and lakes in temperate and cold regions worldwide. Five species are included in the Global Invasive Species Database: rainbow trout Oncorhynchus mykiss, Atlantic salmon Salmo salar, brown trout Salmo trutta, brook trout Salvelinus fontinalis, and lake trout Salvelinus namaycush. In contrast, other salmonids are endangered in their native settings. Methods Here we have developed a method to identify salmonid species directly from water samples, focusing on the Iberian Peninsula as a case study. We have designed nested Salmonidae-specific primers within the 16S rDNA region. From these primers and a PCR-RFLP procedure the target species can be unequivocally identified from DNA extracted from water samples. Results The method was validated in aquarium experiments and in the field with water from watersheds with known salmonid populations. Finally, the method was applied to obtain a global view of the Salmonidae community in Nalón River (north coast of Spain. Discussion This new powerful, very sensitive (identifying the species down to 10 pg DNA/ml water and economical tool can be applied for monitoring the presence of salmonids in a variety of situations, from checking upstream colonization after removal of river barriers to monitoring potential escapes from fish farms.

Seasonal survival rates and causes of mortality of Little Owls in Denmark

DEFF Research Database (Denmark)

Thorup, Kasper; Pedersen, Dorthe; Sunde, Peter

2013-01-01

Survival rate is an essential component of population dynamics; therefore, identification of variation in mortality rates and the factors that influence them might be of key importance in understanding why populations increase or decrease. In Denmark, the Little Owl Athene noctua, a species...... the causes of current survival rates, we estimated age- and season-specific survival rates and causes of mortality in Danish Little Owls on the basis of ringed birds 1920–2002, radio tagged adult and juveniles 2005–2008 and nest surveys 2006–2008. We estimate that 32 % of all eggs fledge and survive to 2...... the breeding season. In radio-tagged adults and fledged juveniles, accidents in buildings and other human infrastructures were responsible for two-thirds of all fatalities. Anthropogenic habitats currently comprise the nesting and roosting habitats for the last Danish Little Owls. The accidental deaths...

Feasibility study for evaluating cumulative exposure of downstream migrant juvenile salmonids to total dissolved gas. Final report

International Nuclear Information System (INIS)

Abernethy, C.S.; Dauble, D.D.; Johnson, R.L.

1997-11-01

A feasibility study was initiated to determine if downstream migrant salmonids could be monitored to determine potential relationships between total dissolved gas (TDG) exposure and signs of gas bubble trauma (GBT). The primary objectives were to: (1) establish logistical requirements for in-river monitoring of TDG exposure, including net pen design, deployment, and navigation constraints; (2) resolve uncertainties associated with effects of the net pen on fish behavior; (3) test the accuracy and precision of in-river monitoring equipment used to measure fish distribution and water quality; and (4) determine the application of hydrologic/flow models to predictions of TDG exposure. In-river measurements included water velocity, boat position, and selected water quality parameters (temperature, dissolved oxygen, pH, depth, conductivity). Fish distribution within the net pen was monitored using scanning sonar, and a split-beam echo sounder was used to evaluate vertical distribution of fish m in the river adjacent to the net pen. Three test drifts were conducted from late July through late August. The studies demonstrated that it was feasible to assemble and deploy a large net pen for mobile monitoring of TDG exposure. Accurate monitoring of vertical and lateral distribution of smolts was performed, and diel differences in behavior were documented. Further, the fish sounded in response to researcher activity on the perimeter platform. Thus, in-transit monitoring for GBT or mortality would affect fish depth distribution and exposure to TDG. Principal recommendations for future studies are directed at improving maneuverability of the net pen in adverse weather conditions and applying new acoustics technology to simultaneously collect fish distribution data from within and outside of the pen. 6 refs., 17 figs., 2 tabs

Review of a model to assess stranding of juvenile salmon by ship wakes along the Lower Columbia River, Oregon and Washington

Science.gov (United States)

Kock, Tobias J.; Plumb, John M.; Adams, Noah S.

2013-01-01

uncertainty within a given set of model predictions, but such an approach would require a substantial amount of additional data collection. Several review questions focused on the accuracy and precision of the model estimates, but we were unable to address these questions because of the limited data that currently exists regarding wake stranding in the LCR. Additional field studies will be required to validate findings from Pearson (2011), if concerns regarding accuracy and precision remain a priority. Although the Pearson (2011) model provided a useful examination of stranding under pre-construction and post-construction conditions, future research will be required to better understand the effects of wake stranding on juvenile salmonids throughout the entire LCR. If additional information on wake stranding is desired in the future, the following topics may be of interest: (1) spatial examination of wake stranding throughout the entire LCR; (2) additional evaluation of juvenile salmonid behavior and population dynamics; (3) assessing and integrating predicted changes in ship development; and (4) assessing and integrating predicted changes in climate on environmental factors known to cause stranding.

Evaluation of Fish Passage Sites in the Walla Walla River Basin, 2008

Energy Technology Data Exchange (ETDEWEB)

Chamness, Mickie A. [Pacific Northwest National Laboratory

2008-08-29

In 2008, Pacific Northwest National Laboratory evaluated the Hofer Dam fish screen and provided technical assistance at two other fish passage sites as requested by the Bonneville Power Administration, the Walla Walla Watershed Council, or the Confederated Tribes of the Umatilla Indian Reservation. Evaluation of new sites such as Hofer Dam focuses on their design, construction, operation, and maintenance to determine if they effectively provide juvenile salmonids with safe passage through irrigation diversions. There were two requests for technical assistance in 2008. In the first, the Confederated Tribes of the Umatilla Indian Reservation requested an evaluation of the Nursery Bridge fish screens associated with the fish ladder on the east side of the Walla Walla River. One set of brushes that clean the screens was broken for an extended period. Underwater videography and water velocity measurements were used to determine there were no potential adverse effects on juvenile salmonids when the west set of screens was clean enough to pass water normally. A second request, received from the National Marine Fisheries Service and the Walla Walla Watershed Council, asked for evaluation of water velocities through relatively new head gates above and adjacent to the Eastside Ditch fish screens on the Walla Walla River. Water moving through the head gates and not taken for irrigation is diverted to provide water for the Nursery Bridge fish ladder on the east side of the river. Elevations used in the design of the head gates were incorrect, causing excessive flow through the head gates that closely approached or exceeded the maximum swimming burst speed of juvenile salmonids. Hofer Dam was evaluated in June 2008. PNNL researchers found that conditions at Hofer Dam will not cause impingement or entrainment of juvenile salmonids but may provide habitat for predators and lack strong sweeping flows to encourage juvenile salmonid passage downstream. Further evaluation of

Development of a System-Wide Predator Control Program: Stepwise Implementation of a Predation Index, Predator Control Fisheries, and Evaluation Plan in the Columbia River Basin; Northern Pikeminnow Management Program, 2001 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Porter, Russell G.; Winther, Eric C.; Fox, Lyle G.

2003-03-01

This report presents results for year eleven in a basin-wide program to harvest northern pikeminnow (Ptychocheilus oregonensis). This program was started in an effort to reduce predation by northern pikeminnow on juvenile salmonids during their emigration from natal streams to the ocean. Earlier work in the Columbia River Basin suggested predation by northern pikeminnow on juvenile salmonids might account for most of the 10-20% mortality juvenile salmonids experience in each of eight Columbia River and Snake River reservoirs. Modeling simulations based on work in John Day Reservoir from 1982 through 1988 indicated that, if predator-size northern pikeminnow were exploited at a 10-20% rate, the resulting restructuring of their population could reduce their predation on juvenile salmonids by 50%. To test this hypothesis, we implemented a sport-reward angling fishery and a commercial longline fishery in the John Day Pool in 1990. We also conducted an angling fishery in areas inaccessible to the public at four dams on the mainstem Columbia River and at Ice Harbor Dam on the Snake River. Based on the success of these limited efforts, we implemented three test fisheries on a system-wide scale in 1991--a tribal longline fishery above Bonneville Dam, a sport-reward fishery, and a dam-angling fishery. Low catch of target fish and high cost of implementation resulted in discontinuation of the tribal longline fishery. However, the sport-reward and dam-angling fisheries were continued in 1992 and 1993. In 1992, we investigated the feasibility of implementing a commercial longline fishery in the Columbia River below Bonneville Dam and found that implementation of this fishery was also infeasible.

Behavioural and Neuroendocrine Effects of Stress in Salmonid Fish

OpenAIRE

Øverli, Øyvind

2001-01-01

Stress can affect several behavioural patterns, such as food intake and the general activity level of an animal. The central monoamine neurotransmitters serotonin, dopamine, and norepinephrine are important in the mediation of both behavioural and neuroendocrine stress effects. This thesis describes studies of two salmonid fish model systems: Fish that become socially dominant or subordinate when reared in pairs, and rainbow trout (Oncorhynchus mykiss) genetically selected for high (HR) and l...

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.

Assessment of Native Salmonids Above Hells Canyon Dam, Idaho, 2004-2005 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Meyer, Kevin A.; Lamansky, Jr., James A. (Idaho Department of Fish and Game, Boise, ID)

2005-08-01

In the western United States, exotic brook trout Salvelinus fontinalis frequently have a deleterious effect on native salmonids, and biologists often attempt to remove brook trout in streams using electrofishing. Although the success of electrofishing removal projects typically is low, few studies have assessed the underlying mechanisms of failure, especially in terms of compensatory responses. We evaluated the effectiveness of a three-year removal project in reducing brook trout and enhancing native salmonids in 7.8 km of an Idaho stream and looked for brook trout compensatory responses such as decreased natural mortality, increased growth, increased fecundity at length, or earlier maturation. Due to underestimates of the distribution of brook trout in the first year and personnel shortages in the third year, the multiagency watershed advisory group that performed the project fully treated the stream (i.e. multipass removals over the entire stream) in only one year. In 1998, 1999, and 2000, a total of 1,401, 1,241, and 890 brook trout were removed, respectively. For 1999 and 2000, an estimated 88 and 79% of the total number of brook trout in the stream were removed. For the section of stream that was treated in all years, the abundance of age-1 and older brook trout decreased by 85% from 1998 to 2003. In the same area, the abundance of age-0 brook trout decreased 86% from 1998 to 1999 but by 2003 had rebounded to near the original abundance. Abundance of native redband trout Oncorhynchus mykiss decreased for age-1 and older fish but did not change significantly for age-0 fish. Despite high rates of removal, total annual survival rate for brook trout increased from 0.08 {+-} 0.02 in 1998 to 0.20 {+-} 0.04 in 1999 and 0.21 {+-} 0.04 in 2000. Growth of age-0 brook trout was significantly higher in 2000 (the year after their abundance was lowest) compared to other years, and growth of age-1 and age-2 brook trout was significantly lower following the initial removal

Research, Monitoring, and Evaluation for the Federal Columbia River Estuary Program

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Diefenderfer, Heida L.; Ebberts, Blaine D.; Tortorici, Cathy; Yerxa, Tracey; Leary, J.; Skalski, John R.

2008-02-05

The purpose ofthis document is to describe research, monitoring, and evaluation (RME) for the Federal Columbia River Estuary Program. The intent of this RME effort is to provide data and information to evaluate progress toward meeting program goals and objectives and support decision-making in the Estuary Program. The goal of the Estuary Program is to understand, conserve, and restore the estuary ecosystem to improve the performance of listed salmonid populations. The Estuary Program has five general objectives, designed to fulfill the program goal, as follows. 1. Understand the primary stressors affecting ecosystem controlling factors, such as ocean conditions and invasive species. 2. Conserve and restore factors controlling ecosystem structures and processes, such as hydrodynamics and water quality. 3. Increase the quantity and quality of ecosystem structures, i.e., habitats, juvenile salmonids use during migration through the estuary. 4. Maintain the food web to benefit salmonid performance. 5. Improve salmonid performance in terms of life history diversity, foraging success, growth, and survival. The goal of estuary RME is to provide pertinent and timely research and monitoring information to planners, implementers, and managers of the Estuary Program. In conclusion, the estuary RME effort is designed to meet the research and monitoring needs of the estuary Program using an adaptive management process. Estuary RME's success and usefulness will depend on the actual conduct of adaptive management, as embodied in the objectives, implrementation, data, reporting, and synthesis, evaluation, and decision-making described herein.

The relationship between survival of Columbia River fall chinook salmon and in-river environmental factors -- Analysis of historic data for juvenile and adult salmonid production: Phase 2. Final report

International Nuclear Information System (INIS)

Skalski, J.R.; Townsend, R.L.; Donnelly, R.F.; Hilborn, R.W.

1996-12-01

This project analyzes in greater detail the coded-wire-tag (CWT) returns of Priest Rapids Hatchery fall chinook for the years 1976--1989 initially begun by Hilborn et al. (1993a). These additional analyses were prompted by suggestions made by peer reviews of the initial draft report. The initial draft and the peer review comments are included in this final report (Appendices A and B). The statistical analyses paired Priest Rapids stock with potential downriver reference stocks to isolate in-river survival rates. Thirty-three potential reference stocks were initially examined for similar ocean recovery rates; the five stocks with the most similar recovery patterns (i.e., Bonneville Brights, Cowlitz, Gray's River, Tanner Creek, and Washougal) to the Priest Rapids stock were used in the subsequent analysis of in-river survival. Three alternate forms of multiple regression models were used to investigate the relationship between predicted in-river survival and ambient conditions. Analyses were conducted with and without attempts to adjust for smolt transportation at McNary Dam. Independent variables examined in the analysis included river flows, temperature, turbidity, and spill along with the total biomass of hatchery releases in the Columbia-Snake River Basin

Juvenile coho salmon growth and health in streams across an urbanization gradient

Science.gov (United States)

Spanjer, Andrew R.; Moran, Patrick W.; Larsen, Kimberly; Wetzel, Lisa; Hansen, Adam G.; Beauchamp, David A.

2018-01-01

Expanding human population and urbanization alters freshwater systems through structural changes to habitat, temperature effects from increased runoff and reduced canopy cover, altered flows, and increased toxicants. Current stream assessments stop short of measuring health or condition of species utilizing these freshwater habitats and fail to link specific stressors mechanistically to the health of organisms in the stream. Juvenile fish growth integrates both external and internal conditions providing a useful indicator of habitat quality and ecosystem health. Thus, there is a need to account for ecological and environmental influences on fish growth accurately. Bioenergetics models can simulate changes in growth and consumption in response to environmental conditions and food availability to account for interactions between an organism's environmental experience and utilization of available resources. The bioenergetics approach accounts for how thermal regime, food supply, and food quality affect fish growth. This study used a bioenergetics modeling approach to evaluate the environmental factors influencing juvenile coho salmon growth among ten Pacific Northwest streams spanning an urban gradient. Urban streams tended to be warmer, have earlier emergence dates and stronger early season growth. However, fish in urban streams experienced increased stress through lower growth efficiencies, especially later in the summer as temperatures warmed, with as much as a 16.6% reduction when compared to fish from other streams. Bioenergetics modeling successfully characterized salmonid growth in small perennial streams as part of a more extensive monitoring program and provides a powerful assessment tool for characterizing mixed life-stage specific responses in urban streams.

Effects of river morphology, hydraulic gradients, and sediment deposition on water exchange and oxygen dynamics in salmonid redds.

Science.gov (United States)

Schindler Wildhaber, Y; Michel, C; Epting, J; Wildhaber, R A; Huber, E; Huggenberger, P; Burkhardt-Holm, P; Alewell, C

2014-02-01

Fine sediment decreasing gravel permeability and oxygen supply to incubating salmonid embryos, is often considered the main contributing factor for the observed decline of salmonid populations. However, oxygen supply to salmonid embryos also depends on hydraulic conditions driving water flow through the redd. A more generalized perspective is needed to better understand the constraints on successful salmonid incubation in the many heavily modified fluvial ecosystems of the Northern Hemisphere. The effects of hydraulic gradients, riverbed and redd morphology as well as fine sediment deposition on dissolved oxygen (DO) and water exchange was studied in 18 artificial redds at three sites along a modified river. Fifty percent of the redds in the two downstream sites were lost during high flow events, while redd loss at the upstream site was substantially lower (8%). This pattern was likely related to increasing flood heights from up- to downstream. Specific water infiltration rates (q) and DO were highly dynamic and driven on multiple temporal and spatial scales. Temporally, the high permeability of the redd gravel and the typical pit-tail structure of the new built redds, leading to high DO, disappeared within a month, when fine sediment had infiltrated and the redd structure was leveled. On the scale of hours to days, DO concentrations and q increased during high flows, but decreased during the falling limb of the water level, most likely related to exfiltration of oxygen depleted groundwater or hyporheic water. DO concentrations also decreased under prolonged base flow conditions, when increased infiltration of silt and clay particles clogged the riverbed and reduced q. Spatially, artificial log steps affected fine sediment infiltration, q and interstitial DO in the redds. The results demonstrate that multiple factors have to be considered for successful river management in salmonid streams, including riverbed structure and local and regional hydrogeological

Stress and food deprivation: linking physiological state to migration success in a teleost fish

DEFF Research Database (Denmark)

Midwood, J.D.; Larsen, Martin Hage; Aarestrup, Kim

2016-01-01

for the cortisol treatment. Food availability and individual energetic state appear to dictate the future life-history strategy (migrate or remain resident) of juvenile salmonids while experimental elevation of the stress hormone cortisol caused impaired growth and reduced survival of both resident and migratory......Food deprivation (FD) is a naturally occurring stressor that is thought to influence the ultimate life-history strategy of individuals. Little is known about how FD interacts with other stressors to influence migration success. European populations of brown trout (Salmo trutta) exhibit partial...... of the glucocorticoid stress response in determining life-history strategy and survival of a migratory species. Using an experimental approach, the relative influences of short-term FD and experimental cortisol elevation (i.e., intra-coelomic injection of cortisol suspended in cocoa butter) on migratory status...

Effects of feed species and HUFA composition on survival and growth of the longsnout seahorse (Hippocampus reidi

Directory of Open Access Journals (Sweden)

Patrick eSchubert

2016-04-01

Full Text Available Globally, wild seahorse populations are threatened due to, habitat destruction and unsustainable human exploitation among others. Furthermore, aquaculture-based mass-scale rearing is still uncommon due to the low survival rates of seahorse juveniles and exceptionally high feed costs. Previous studies have demonstrated the importance of both highly unsaturated fatty acid (HUFA supplies and a copepod-based rearing for seahorse survival and growth. As the latter is expensive, the question arises as to how high survival rates of seahorse juveniles can be assured under low- to moderate-cost feed regimes. In particular, it remains unknown whether the diet species or their dietary HUFA profiles determine the successful development of seahorse fry.Therefore, the aims of this study were to assess the dependence of growth and survival rates of Hippocampus reidi brood on the animal feed and to infer the impact of feed species vs. dietary HUFA profiles on juvenile growth. A nutrition experiment was conducted where juveniles were treated either with enriched Artemia nauplii (low-cost diet Art or with a mixed diet of Artemia and copepods (moderate-cost diet Art/Cop. Larval survival and growth were analyzed using Cox proportional-hazard and mixed linear model analyses. We found that i both diets enabled good survival, ii diet Art/Cop resulted in superior weight and height growth, and iii the differential effects of diets Art/Cop and Art cannot be explained by their different HUFA compositions alone.From an economical point of view, our findings of high survival rates and relatively high growth rates with the medium-cost treatment Art/Cop may open new possibilities for the large-scale rearing of seahorses. Even the application of a low-cost Art diet might be appropriate for seahorse aquacultures as both survival and growth rates are only marginally lower compared to the former diet.

A protocol using coho salmon to monitor Tongass National Forest Land and Resource Management Plan standards and guidelines for fish habitat.

Science.gov (United States)

M.D. Bryant; Trent McDonald; R. Aho; B.E. Wright; Michelle Bourassa Stahl

2008-01-01

We describe a protocol to monitor the effectiveness of the Tongass Land Management Plan (TLMP) management standards for maintaining fish habitat. The protocol uses juvenile coho salmon (Oncorhynchus kisutch) in small tributary streams in forested watersheds. We used a 3-year pilot study to develop detailed methods to estimate juvenile salmonid...

The effect of chlorpyrifos on salinity acclimation of juvenile rainbow trout (Oncorhynchus mykiss).

Science.gov (United States)

Amiri, Bagher Mojazi; Xu, Elvis Genbo; Kupsco, Allison; Giroux, Marissa; Hoseinzadeh, Mahbubeh; Schlenk, Daniel

2018-02-01

As a part of their unique life cycle, most salmonids undergo a transition from fresh water to salt water requiring various adjustments in metabolism, osmoregulation and ion regulation. Exposure to pesticides may affect the acclimation of juvenile salmonids to salt water during downstream migration to estuaries. Using the Caspian Sea as a model waterbody, the present study aimed to determine how the toxicity of the organophosphate pesticide chlorpyrifos (CPF) impacts saline acclimation of rainbow trout (Oncorhynchus mykiss). We pre-exposed 4-month-old fish to nominal concentrations of 0, 20, 40, 80, 160 μg/L of CPF for seven days, and then gradually to salinity (12 ppt) for another seven days. Mortality, levels of cortisol, T3 and T4 in serum, and expression of genes involved in gill ion transport (Na + /K + ATPase α1a and α1b) and liver xenobiotic detoxification (Glutathione-S-Transferase pi, GST) were measured at day fourteen. Cortisol concentrations in serum were not changed by CPF exposure in freshwater, but serum T3 increased up to three fold relative to controls in freshwater. Following salinity acclimation, T3 and T4 concentrations in the serum were both increased up to 2.5 and 8.8 fold in animals treated with CPF followed by saltwater. Na+/K + ATPase α1a and α1b mRNA in gill were unchanged by CPF treatment in freshwater but trended higher in CPF-treated animals after salinity acclimation. Hepatic mRNA of GST was significantly increased following exposure to CPF but was unchanged after saltwater exposure. Although saltwater treatment reduced the acute lethality of CPF, changes in T3/T4 suggest sublethal impacts may occur in CPF-treated fish after they acclimate to Caspian seawater. Copyright © 2017 Elsevier B.V. All rights reserved.

A 3D approximate maximum likelihood solver for localization of fish implanted with acoustic transmitters

Science.gov (United States)

Li, Xinya; Deng, Z. Daniel; Sun, Yannan; Martinez, Jayson J.; Fu, Tao; McMichael, Geoffrey A.; Carlson, Thomas J.

2014-11-01

Better understanding of fish behavior is vital for recovery of many endangered species including salmon. The Juvenile Salmon Acoustic Telemetry System (JSATS) was developed to observe the out-migratory behavior of juvenile salmonids tagged by surgical implantation of acoustic micro-transmitters and to estimate the survival when passing through dams on the Snake and Columbia Rivers. A robust three-dimensional solver was needed to accurately and efficiently estimate the time sequence of locations of fish tagged with JSATS acoustic transmitters, to describe in sufficient detail the information needed to assess the function of dam-passage design alternatives. An approximate maximum likelihood solver was developed using measurements of time difference of arrival from all hydrophones in receiving arrays on which a transmission was detected. Field experiments demonstrated that the developed solver performed significantly better in tracking efficiency and accuracy than other solvers described in the literature.

Chronic effects of nitrogenous compounds on survival and growth of juvenile pink shrimp.

Science.gov (United States)

Wasielesky, W J; Poersch, L H; Martins, T G; Miranda-Filho, K C

2017-01-01

In response to growing worldwide market demand, intensive shrimp farming, based on high feed, has developed over the past decade. The nitrogenous compounds mainly generated by animal excretion can cause deterioration of water quality and produce chronic or even acute toxicity to aquatic animals. As prevention, theoretical safety levels have been estimated from acute toxicity tests and they are traditionally used to prevent toxic effects on biota. However, are those concentrations of nitrogenous compounds really safe to Farfantepenaeus paulensis? The current study aimed to investigate the lethal and sublethal effects of ammonia, nitrite and nitrate to juvenile F. paulensis based on safety levels. Each experiment was performed independently in 100 L tanks for 30 days. The survival rates and wet weight of all shrimps were recorded every 10 days. The concentrations tested for ammonia, nitrite and nitrate were respectively: treatment "T1/4", a quarter of the safety level (0.91 mg/L TA-N, 2.55 mg/L NO2--N and 80.7 mg/L NO3--N); treatment "TSL", the safety level (3.65 mg/L TA-N, 10.2 mg/L NO2--N and 323 mg/L NO3--N); and treatment "T2X", twice the safety level (7.30 mg/L TA-N, 20.4 mg/L NO2--N and 646 mg/L NO3--N). For F. paulensis cultivation, the real safety level for nitrite was estimated to be 2.55 mg/L NO2--N. For ammonia and nitrate, the recommended concentrations were <0.91 mg/L TA-N corresponding to 0.045 mg/L NH3-N and <80.7 mg/L NO3--N, respectively.

Predictability of multispecies competitive interactions in three populations of Atlantic salmon Salmo salar.

Science.gov (United States)

Houde, A L S; Wilson, C C; Neff, B D

2015-04-01

Juvenile Atlantic salmon Salmo salar from three allopatric populations (LaHave, Sebago and Saint-Jean) were placed into artificial streams with combinations of four non-native salmonids: brown trout Salmo trutta, rainbow trout Oncorhynchus mykiss, Chinook salmon Oncorhynchus tshawytscha and coho salmon Oncorhynchus kisutch. Non-additive effects, as evidenced by lower performance than predicted from weighted summed two-species competition trials, were detected for S. salar fork length (LF ) and mass, but not for survival, condition factor or riffle use. These data support emerging theory on niche overlap and species richness as factors that can lead to non-additive competition effects. © 2015 The Fisheries Society of the British Isles.

Feeding Activity, Rate of Consumption, Daily Ration and Prey Selection of Major Predators in John Day Reservoir, 1985: Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Palmer, Douglas E.; United States. Bonneville Power Administration; U.S. Fish and Wildlife Service; National Fishery Research Center (U.S.)

1986-10-01

This report summarizes activities in 1985 to determine the extent of predation on juvenile salmonids in John Day Reservoir. To estimate consumption of juvenile salmonids we used the composition of the natural diet of predators and in the laboratory determined rate of gastric evacuation by predators. Salmonids were the single most important food item for northern squawfish (Ptychocheilus oregonensis) at McNary tailrace during all sampling periods and at John Day forebay during July. Salmonids accounted for 11.6% of the diet of walleye (Stizostedion vitreum vitreum) in 1985 which was about twice that found in previous years. Salmonids contributed little to smallmouth bass (Micropterus dolomieui) diet but comprised about 25% of the diet of channel catfish (Ictalurus punctatus). Composition of prey taxa in beach seine catches in 1985 was similar to 1983 and 1984 with chinook salmon (Oncorhynchus tschawytscha), northern squawfish, largescale sucker (Catostomus macrocheilus), and sand roller (Percopsis transmontana) dominating the catch at main channel stations and crappies (Pomoxis spp.) and largescale sucker dominating at backwater stations. Preliminary results of beach seine efficiency studies suggest that seine efficiency varied significantly among prey species and between substrate types in 1985. Results of digestion rate experiments indicate that gastric evacuation in northern squawfish can be predicted using water temperature, prey weight, predator weight and time. 19 refs., 19 figs., 13 tabs.

Juvenile Chinook Salmon mortality in a Snake River Reservoir: Smallmouth Bass predation revisited

Science.gov (United States)

Erhardt, John M.; Tiffan, Kenneth F.; Connor, William P.

2018-01-01

Predation by nonnative fishes has been identified as a contributing factor in the decline of juvenile salmonids in the Columbia River basin. We examined the diet composition of Smallmouth Bass Micropterus dolomieu and estimated the consumption and predation loss of juvenile Chinook Salmon Oncorhynchus tshawytscha in Lower Granite Reservoir on the Snake River. We examined 4,852 Smallmouth Bass stomachs collected from shoreline habitats during April–September 2013–2015. Chinook Salmon were the second most commonly consumed fish by all size‐classes of Smallmouth Bass (≥150 mm TL) throughout the study. Over the 3 years studied, we estimated that a total of 300,373 Chinook Salmon were consumed by Smallmouth Bass in our 22‐km study area, of which 97% (291,884) were subyearlings (age 0) based on length frequency data. A majority of the loss (61%) occurred during June, which coincided with the timing of hatchery releases of subyearling fall Chinook Salmon. Compared to an earlier study, mean annual predation loss increased more than 15‐fold from 2,670 Chinook Salmon during 1996–1997 to 41,145 Chinook Salmon during 2013–2015 (in reaches that could be compared), despite lower contemporary Smallmouth Bass abundances. This increase can be explained in part by increases in Smallmouth Bass consumption rates, which paralleled increases in subyearling Chinook Salmon densities—an expected functional response by an opportunistic consumer. Smallmouth Bass are currently significant predators of subyearling Chinook Salmon in Lower Granite Reservoir and could potentially be a large source of unexplained mortality.

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

Energy Technology Data Exchange (ETDEWEB)

Trudel, Marc; Tucker, Strahan; Morris, John

2009-03-09

Historically, salmon stocks from the Columbia River and Snake River formed one of the most valuable fisheries on the west coast of North America. However, salmon and steelhead returns sharply declined during the 1980s and 1990s to reach nearly 1 million fish. Although several factors may be responsible for the decline of Columbia River salmon and steelhead, there is increasing evidence that these drastic declines were primarily attributable to persistently unfavorable ocean conditions. Hence, an understanding of the effects of ocean conditions on salmon production is required to forecast the return of salmon to the Columbia River basin and to assess the efficacy of mitigation measures such as flow regulation on salmon resources in this system. The Canadian Program on High Seas Salmon has been collecting juvenile salmon and oceanographic data off the west coast of British Columbia and Southeast Alaska since 1998 to assess the effects of ocean conditions on the distribution, migration, growth, and survival of Pacific salmon. Here, we present a summary of the work conducted as part of the Canada-USA Salmon Shelf Survival Study during the 2008 fiscal year and compare these results with those obtained from previous years. The working hypothesis of this research is that fast growth enhances the marine survival of salmon, either because fast growing fish quickly reach a size that is sufficient to successfully avoid predators, or because they accumulate enough energy reserves to better survive their first winter at sea, a period generally considered critical in the life cycle of salmon. Sea surface temperature decreased from FY05 to FY08, whereas, the summer biomass of phytoplankton increased steadily off the west coast of Vancouver Island from FY05 to FY08. As in FY07, zooplankton biomass was generally above average off the west coast of Vancouver Island in FY08. Interestingly, phytoplankton and zooplankton biomass were higher in FY08 than was expected from the observed

Juvenile rheumatoid arthritis

Science.gov (United States)

... joints. This form of JIA may turn into rheumatoid arthritis. It may involve 5 or more large and ... no known prevention for JIA. Alternative Names Juvenile rheumatoid arthritis (JRA); Juvenile chronic polyarthritis; Still disease; Juvenile spondyloarthritis ...

marine survival ecosystem indicators - Estimating the ecosystem indicators of anadromous salmonids in the Puget Sound region

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The objective of this project is to develop a simple approach for estimating the marine survival and causes of trends in survival. Data is a summary of ecosystem...

Survival benefits of post-fledging care: experimental approach to a critical part of avian reproductive strategies.

Science.gov (United States)

Grüebler, Martin U; Naef-Daenzer, Beat

2010-03-01

1. Caring for offspring beyond leaving the nest is an important but under-studied part of avian life histories. Theory predicts that prolonged post-fledging parental care should yield fitness benefits such as increased fledgling survival. Post-fledging care is also costly in terms of time and energy available for subsequent reproduction, moult or migration. So far, direct measurements of the fitness effects of the duration of post-fledging parental care are lacking. 2. In a partial cross-fostering experiment, barn swallow (Hirundo rustica) chicks were exchanged among broods close to fledging. Thereby, we separated the effects of post-fledging care from those of pre-fledging origin on juvenile survival. 3. Prolonging post-fledging care substantially increased juvenile survival up to 3 weeks post-fledging. Juvenile mortality was maximal in the days following the termination of parental care, and prolonging care delayed and reduced this peak mortality. Survival of fledglings experiencing 6 days of care was Phi = 0.227, whereas fledglings experiencing 14 days of care showed a survival of Phi = 0.571. 4. Offspring from pairs providing short care showed lower post-fledging survival than did offspring from pairs providing long care, irrespective of the actual duration of care experienced. This gives evidence for an additional survival effect of pre-fledging factors associated with the parental duration of care. 5. The results suggest that differential survival in relation to post-fledging parental care is a major fitness component. This relationship has profound effects on the reproductive trade-offs underlying the evolution of avian life histories.

PCR-RFLP Method to Identify Salmonid Species of Economic Importance

Directory of Open Access Journals (Sweden)

Andreea Dudu

2011-05-01

Full Text Available The identification of different fish species by molecular methods has become necessary to avoid both the incorrect labelling of individuals involved in repopulation programmes and the commercial frauds on the fish market. Different fish species of great economical importance, like the salmonids, which are very much requested for their meat, can be identified using molecular techniques such as PCR-RFLP. The method is based on the amplification of a target region from the genome by PCR reaction followed by endonucleases digestion to detect the polymorphism of restriction fragments. In our study we analysed the following salmonid species from Romania: Salmo trutta fario, Salmo labrax, Salvelinus fontinalis, Onchorhynchus mykiss, Thymallus thymallus and Hucho hucho. In order to discriminate between the analysed species we amplified a fragment of mitochondrial genome comprising tRNAGlu/ cytochrome b/ tRNAThr/ tRNAPro/ D-loop/ tRNAPhe, followed by digestion with a specific restriction enzyme. The direct digestion of unpurified PCR products generated species-specific restriction patterns and proved to be a simple, reliable, inexpensive and fast method. Thus, it may be successfully utilized in specialized laboratories for the correct identification of the fish species for multiple purposes, including the traceability of fish food products.

Low Temperature-Dependent Salmonid Alphavirus Glycoprotein Processing and Recombinant Virus-Like Particle Formation

NARCIS (Netherlands)

Metz, S.W.H.; Feenstra, F.; Villoing, S.; Hulten, van M.C.; Lent, van J.W.M.; Koumans, J.; Vlak, J.M.; Pijlman, G.P.

2011-01-01

Pancreas disease (PD) and sleeping disease (SD) are important viral scourges in aquaculture of Atlantic salmon and rainbow trout. The etiological agent of PD and SD is salmonid alphavirus (SAV), an unusual member of the Togaviridae (genus Alphavirus). SAV replicates at lower temperatures in fish.

The Effect of an Externally Attached Neutrally Buoyant Transmitter on Mortal Injury during Simulated Hydroturbine Passage

Energy Technology Data Exchange (ETDEWEB)

Brown, Richard S.; Pflugrath, Brett D.; Carlson, Thomas J.; Deng, Zhiqun

2012-02-03

On their seaward migration, juvenile salmonids commonly pass hydroelectric dams. Fish passing through hydroturbines experience a rapid decrease in pressure as they pass by the turbine blade and the severity of this decompression can be highly variable. This rapid decrease in pressure can result in injuries such as swim bladder rupture, exophthalmia, and emboli and hemorrhaging in the fins and tissues. However, recent research indicates that the presence of a telemetry tag (acoustic, radio, inductive) implanted inside the coelom of a juvenile salmon increases the likelihood that the fish will be injured or die during turbine passage. Thus, previous research conducted using telemetry tags implanted into the coelom of fish may have been inaccurate. Thus, a new technique is needed to provide unbiased estimates of survival through turbines. This research provides an evaluation of the effectiveness of a neutrally buoyant externally attached acoustic transmitter. Both nontagged fish and fish tagged with a neutrally buoyant external transmitter were exposed to a range of rapid decompressions simulating turbine passage. Juvenile Chinook salmon tagged with a neutrally buoyant externally attached acoustic transmitter did not receive a higher degree of barotrauma than their nontagged counterparts. We suggest that future research include field-based comparisons of survival and behavior among fish tagged with a neutrally buoyant external transmitter and those internally implanted with transmitters.

From metamorphosis to maturity in complex life cycles: equal performance of different juvenile life history pathways.

Science.gov (United States)

Schmidt, Benedikt R; Hödl, Walter; Schaub, Michael

2012-03-01

Performance in one stage of a complex life cycle may affect performance in the subsequent stage. Animals that start a new stage at a smaller size than conspecifics may either always remain smaller or they may be able to "catch up" through plasticity, usually elevated growth rates. We study how size at and date of metamorphosis affected subsequent performance in the terrestrial juvenile stage and lifetime fitness of spadefoot toads (Pelobates fuscus). We analyzed capture-recapture data of > 3000 individuals sampled during nine years with mark-recapture models to estimate first-year juvenile survival probabilities and age-specific first-time breeding probabilities of toads, followed by model selection to assess whether these probabilities were correlated with size at and date of metamorphosis. Males attained maturity after two years, whereas females reached maturity 2-4 years after metamorphosis. Age at maturity was weakly correlated with metamorphic traits. In both sexes, first-year juvenile survival depended positively on date of metamorphosis and, in males, also negatively on size at metamorphosis. In males, toads that metamorphosed early at a small size had the highest probability to reach maturity. However, because very few toadlets metamorphosed early, the vast majority of male metamorphs had a very similar probability to reach maturity. A matrix projection model constructed for females showed that different juvenile life history pathways resulted in similar lifetime fitness. We found that the effects of date of and size at metamorphosis on different juvenile traits cancelled each other out such that toads that were small or large at metamorphosis had equal performance. Because the costs and benefits of juvenile life history pathways may also depend on population fluctuations, ample phenotypic variation in life history traits may be maintained.

Criteria for sustainable fisheries on juveniles illustrated for Mediterranean hake: control the juvenile harvest, and safeguard spawning refugia to rebuild population fecundity

Directory of Open Access Journals (Sweden)

John F. Caddy

2015-09-01

Full Text Available The paper provides a broad overview of issues relevant to management of fisheries for juvenile fish in contrast to the many stock assessments following Beverton and Holt’s (1957 approach for rational exploitation of mature fishes. A perspective on assessing these fisheries is illustrated for juvenile European hake, Merluccius merluccius, in the northwestern Mediterranean. Here, a constant natural mortality (M assumption is incorrect, as is the assumption that high fecundities are necessarily adequate for stock replacement. The high Ms-at-age for juveniles generated by the reciprocal model are shown to be a logical counterpart to the high fecundity of hake. Charnov’s criterion of intergenerational reproductive replacement is used to test for a sustainable population, analogous to a limit reference point warning of the dangers of overfishing beyond population replacement. Once peak mortality rates of age 2 hake exceed F(2=1.1-1.2, which is currently the case, reproductive replacement may be at risk. Adult exploitation by inshore trawls is low, and maturing hake surviving the fine-mesh trawl fishery migrate offshore with a reduced vulnerability to fine-mesh gears. Early research suggested that rough bottom near the shelf edge once formed a refugium protecting offshore spawners from trawling, and led to abundant recruitment of juveniles nearer shore. It may not do so if offshore fishing effort by reinforced bottom trawls, gill nets and longlines is uncontrolled. Restoring offshore refugia to protect spawners and controlling peak fishing mortality of juveniles would be a precautionary strategy aimed at restoring previous levels of recruitment to the small-mesh trawl fishery.

SPATACSIN mutations cause autosomal recessive juvenile amyotrophic lateral sclerosis

OpenAIRE

Orlacchio, Antonio; Babalini, Carla; Borreca, Antonella; Patrono, Clarice; Massa, Roberto; Basaran, Sarenur; Munhoz, Renato P.; Rogaeva, Ekaterina A.; St George-Hyslop, Peter H.; Bernardi, Giorgio; Kawarai, Toshitaka

2010-01-01

The mutation of the spatacsin gene is the single most common cause of autosomal recessive hereditary spastic paraplegia with thin corpus callosum. Common clinical, pathological and genetic features between amyotrophic lateral sclerosis and hereditary spastic paraplegia motivated us to investigate 25 families with autosomal recessive juvenile amyotrophic lateral sclerosis and long-term survival for mutations in the spatascin gene. The inclusion criterion was a diagnosis of clinically definite ...

Comparison of Treatment Results Between Adult and Juvenile Nasopharyngeal Carcinoma

International Nuclear Information System (INIS)

Downing, N. Lance; Wolden, Suzanne; Wong, Priscilla; Petrik, David W.; Hara, Wendy; Le, Quynh-Thu

2009-01-01

Purpose: Nasopharyngeal carcinoma (NPC) has a bimodal age distribution. In contrast to the adult variant, little is known about the juvenile form. This study examined the treatment results between adult (aNPC) and juvenile NPC (jNPC) patients for future treatment considerations in jNPC. Methods and Materials: The jNPC population included 53 patients treated at two institutions between 1972 and 2004. The aNPC population included 84 patients treated at one institution. The patients had received a median dose of 66 Gy of external beam radiotherapy and 72% underwent chemotherapy. The mean follow-up for surviving patients was 12.6 years for jNPC and 6.6 years for aNPC. Results: The jNPC patients presented with more advance stages than did the aNPC patients (92% vs. 67% Stage III-IV, p = .006). However, jNPC patients had significantly better overall survival (OS) than did aNPC patients. The 5-year OS rate was 71% for jNPC and 58% for aNPC (p = .03). The jNPC group also demonstrated a trend for greater relapse-free survival than the aNPC group (5-year relapse-free survival rate, 69% vs. 49%; p = .056). The pattern of failure analysis revealed that the jNPC patients had greater locoregional control and freedom from metastasis but the differences were not statistically significant. Univariate analysis for OS revealed that age group, nodal classification, and chemotherapy use were significant prognostic factors. Age group remained significant for OS on multivariate analysis, after adjusting for N classification and treatment. Conclusion: Despite more advance stage at presentation, jNPC patients had better survival than did aNPC patients. Future treatment strategies should take into consideration the long-term complications in these young patients.

Chronic effects of nitrogenous compounds on survival and growth of juvenile pink shrimp

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W. J. Wasielesky

Full Text Available Abstract In response to growing worldwide market demand, intensive shrimp farming, based on high feed, has developed over the past decade. The nitrogenous compounds mainly generated by animal excretion can cause deterioration of water quality and produce chronic or even acute toxicity to aquatic animals. As prevention, theoretical safety levels have been estimated from acute toxicity tests and they are traditionally used to prevent toxic effects on biota. However, are those concentrations of nitrogenous compounds really safe to Farfantepenaeus paulensis? The current study aimed to investigate the lethal and sublethal effects of ammonia, nitrite and nitrate to juvenile F. paulensis based on safety levels. Each experiment was performed independently in 100 L tanks for 30 days. The survival rates and wet weight of all shrimps were recorded every 10 days. The concentrations tested for ammonia, nitrite and nitrate were respectively: treatment “T1/4”, a quarter of the safety level (0.91 mg/L TA-N, 2.55 mg/L NO2--N and 80.7 mg/L NO3--N; treatment “TSL”, the safety level (3.65 mg/L TA-N, 10.2 mg/L NO2--N and 323 mg/L NO3--N; and treatment “T2X”, twice the safety level (7.30 mg/L TA-N, 20.4 mg/L NO2--N and 646 mg/L NO3--N. For F. paulensis cultivation, the real safety level for nitrite was estimated to be 2.55 mg/L NO2--N. For ammonia and nitrate, the recommended concentrations were <0.91 mg/L TA-N corresponding to 0.045 mg/L NH3-N and <80.7 mg/L NO3--N, respectively.

Differential survival among sSOD-1* genotypes in Chinook Salmon

Science.gov (United States)

Hayes, Michael C.; Reisenbichler, Reginald R.; Rubin, Stephen P.; Wetzel, Lisa A.; Marshall , Anne R.

2011-01-01

Differential survival and growth were tested in Chinook salmon Oncorhynchus tshawytscha expressing two common alleles, *–100 and *–260, at the superoxide dismutase locus (sSOD-1*). These tests were necessary to support separate studies in which the two alleles were used as genetic marks under the assumption of mark neutrality. Heterozygous adults were used to produce progeny with –100/–100, –100/–260, and –260/–260 genotypes that were reared in two natural streams and two hatcheries in the states of Washington and Oregon. The latter also were evaluated as returning adults. In general, the genotype ratios of juveniles reared at hatcheries were consistent with high survival and little or no differential survival in the hatchery. Adult returns at one hatchery were significantly different from the expected proportions, and the survival of the –260/–260 genotype was 0.56–0.89 times that of the –100/–100 genotype over four year-classes. Adult returns at a second hatchery (one year-class) were similar but not statistically significant: survival of the –260/–260genotype relative to the –100/–100 genotype was 0.76. The performance of the heterozygote group was intermediate at both hatcheries. Significant differences in growth were rarely observed among hatchery fish (one year-class of juveniles and one age-class of adult males) but were consistent with greater performance for the –100/–100 genotype. Results from two groups of juveniles reared in streams (one year-class from each stream) suggested few differences in growth, but the observed genotype ratios were significantly different from the expected ratios in one stream. Those differences were consistent with the adult data; survival for the –260/–260 genotype was 76% of that of the –100/–100 genotype. These results, which indicate nonneutrality among sSOD-1* genotypes, caused us to modify our related studies and suggest caution in the interpretation of results and analyses in

Development of a System wide Predator Control Program: Stepwise Implementation of a Predation Index, Predator Control Fisheries, and Evaluation Plan in the Columbia River Basin; Section II: Evaluation; 1996 Annual Report

International Nuclear Information System (INIS)

Young, Franklin R.

1997-01-01

Predator control fisheries aimed at reducing predation on juvenile salmonids by northern squawfish (Ptychocheilus oregonensis) were implemented for the seventh consecutive year in the mainstream Columbia and Snake rivers

Assessment of Salmonids and their Habitat Conditions in the Walla Walla River Basin within Washington, 2001 Annual Report.

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Mendel, Glen Wesley; Trump, Jeremy; Karl, David

2002-12-01

Concerns about the decline of native salmon and trout populations have increased among natural resource managers and the public in recent years. As a result, a multitude of initiatives have been implemented at the local, state, and federal government levels. These initiatives include management plans and actions intended to protect and restore salmonid fishes and their habitats. In 1998 bull trout (Salvelinus confluentus) were listed under the Endangered Species Act (ESA), as ''Threatened'', for the Walla Walla River and its tributaries. Steelhead (Oncorhynchus mykiss) were listed as ''Threatened'' in 1999 for the mid-Columbia River and its tributaries. These ESA listings emphasize the need for information about these threatened salmonid populations and their habitats. The Washington Department of Fish and Wildlife (WDFW) is entrusted with ''the preservation, protection, and perpetuation of fish and wildlife....[and to] maximize public recreational or commercial opportunities without impairing the supply of fish and wildlife (WAC 77.12.010).'' In consideration of this mandate, the WDFW submitted a proposal in December 1997 to the Bonneville Power Administration (BPA) for a study to assess salmonid distribution, relative abundance, genetics, and the condition of salmonid habitats in the Walla Walla River basin. The primary purposes of this project are to collect baseline biological and habitat data, to identify major data gaps, and to draw conclusions whenever possible. The study reported herein details the findings of the 2001 field season (March to November, 2001).

Survival and metamorphosis of larval sea lamprey (Petromyzon marinus) residing in Lakes Michigan and Huron near river mouths

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Johnson, Nicholas S.; Brenden, Travis O.; Swink, William D.; Lipps, Mathew A.

2016-01-01

Although population demographics of larval lampreys in streams have been studied extensively, demographics in lake environments have not. Here, we estimated survival and rates of metamorphosis for larval sea lamprey (Petromyzon marinus) populations residing in the Great Lakes near river mouths (hereafter termed lentic areas). Tagged larvae were stocked and a Bayesian multi-state tag-recovery model was used to investigate population parameters associated with tag recovery, including survival and metamorphosis probabilities. Compared to previous studies of larvae in streams, larval growth in lentic areas was substantially slower (Brody growth coefficient = 0.00132; estimate based on the recovery of six tagged larvae), survival was slightly greater (annual survival = 63%), and the length at which 50% of the larvae would be expected to metamorphose was substantially shorter (126 mm). Stochastic simulations were used to estimate the production of parasitic stage (juvenile) sea lamprey from a hypothetical population of larvae in a lentic environment. Production of juvenile sea lamprey was substantial because, even though larval growth in these environments was slow relative to stream environments, survival was high and length at metamorphosis was less. However, estimated production of juvenile sea lamprey was less for the lentic environment than for similar simulations for river environments where larvae grew faster. In circumstances where the cost to kill a larva with lampricide was equal and control funds are limited, sea lamprey control effort may be best directed toward larvae in streams with fast-growing larvae, because stream-produced larvae will most likely contribute to juvenile sea lamprey populations.

Correlated growth and survival of juvenile spectacled eiders: Evidence of habitat limitation?

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Flint, Paul L.; Morse, Julie A.; Grand, James B.; Moran, Christine L.

2006-01-01

We studied the growth and survival of Spectacled Eider (Somateria fischeri) ducklings to 30 days of age along the lower Kashunuk River on the Yukon-Kuskokwim Delta from 1995 to 2000. We replicated this study at a second site, Kigigak Island, in 1999 and 2000. Age-adjusted estimates of duckling mass and survival at 30 days posthatching were highly variable. Duckling survival was consistently higher on Kigigak Island in 1999 and 2000, averaging 67%, while survival on the Kashunuk River averaged 45% during the same time period. Duckling survival was negatively related to hatching date. At the Kashunuk River site our data supported models that indicated age-adjusted mass varied with habitat type and declined with hatching date. Ducklings from Kashunuk River were heavier in 1999, while ducklings from Kigigak Island were heavier in 2000. However, we found a positive correlation between 30-day duckling survival and age-adjusted mass, suggesting a localized environmental effect on both parameters. We conclude that predation may be the proximate mechanism of mortality, but habitat conditions are likely the ultimate factors influencing duckling survival. Geographic variation in rates of duckling survival and apparent growth suggest that spatial heterogeneity in population vital rates is occurring at multiple levels.

Conceptualizing juvenile prostitution as child maltreatment: findings from the National Juvenile Prostitution Study.

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Mitchell, Kimberly J; Finkelhor, David; Wolak, Janis

2010-02-01

Two studies were conducted to identify the incidence (Study 1) and characteristics (Study 2) of juvenile prostitution cases known to law enforcement agencies in the United States. Study 1 revealed a national estimate of 1,450 arrests or detentions (95% confidence interval [CI]: 1,287-1,614) in cases involving juvenile prostitution during a 1-year period. In Study 2, exploratory data were collected from a subsample of 138 cases from police records in 2005. The cases are broadly categorized into three main types: (a) third-party exploiters, (b) solo prostitution, and (c) conventional child sexual abuse (CSA) with payment. Cases were classified into three initial categories based on police orientation toward the juvenile: (a) juveniles as victims (53%), (b) juveniles as delinquents (31%), and (c) juvenile as both victims and delinquents (16%). When examining the status of the juveniles by case type, the authors found that all the juveniles in CSA with payment cases were treated as victims, 66% in third-party exploiters cases, and 11% in solo cases. Findings indicate law enforcement responses to juvenile prostitution are influential in determining whether such youth are viewed as victims of commercial sexual exploitation or as delinquents.

Evaluation of stream flow effects on smolt survival in the Yakima River Basin, Washington, 2012-2014

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Courter, Ian; Garrison, Tommy; Kock, Tobias J.; Perry, Russell W.

2015-01-01

The influence of stream flow on survival of emigrating juvenile (smolts) Pacific salmon Oncorhynchus spp. and steelhead trout O. mykiss is of key management interest. However, few studies have quantified flow effects on smolt migration survival, and available information does not indicate a consistent flow-survival relationship within the typical range of flows under management control. It is hypothesized that smolt migration and dam passage survival are positively correlated with stream flow because higher flows increase migration rates, potentially reducing exposure to predation, and reduce delays in reservoirs. However, available empirical data are somewhat equivocal concerning the influence of flow on smolt survival and the underlying mechanisms driving this relationship. Stream flow effects on survival of emigrating anadromous salmonids in the Yakima Basin have concerned water users and fisheries managers for over 20 years, and previous studies do not provide sufficient information at the resolution necessary to inform water operations, which typically occur on a small spatiotemporal scale. Using a series of controlled flow releases from 2012-2014, combined with radio telemetry, we quantified the relationship between flow and smolt survival from Roza Dam 208 km downstream to the Yakima River mouth, as well as for specific routes of passage at Roza Dam. A novel multistate mark-recapture model accounted for weekly variation in flow conditions experienced by radio-tagged fish. Groups of fish were captured and radio-tagged at Roza Dam and released at two locations, upstream at the Big Pines Campground (river kilometer [rkm] 211) and downstream in the Roza Dam tailrace (rkm 208). A total of 904 hatchery-origin yearling Chinook salmon O. tshawytscha were captured in the Roza Dam fish bypass, radio-tagged and released upstream of Roza Dam. Two hundred thirty seven fish were released in the tailrace of Roza Dam. Fish released in the tailrace of Roza Dam were tagged

Hydroacoustic Evaluation of Fish Passage through Bonneville Dam in 2004

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Ploskey, Gene R.; Weiland, Mark A.; Schilt, Carl R.; Kim, Jina; Johnson, Peter N.; Hanks, Michael E.; Patterson, Deborah S.; Skalski, John R.; Hedgepeth, J

2005-12-22

The Portland District of the U.S. Army Corps of Engineers requested that the Pacific Northwest National Laboratory (PNNL) conduct fish-passage studies at Bonneville Dam in 2004. These studies support the Portland District's goal of maximizing fish-passage efficiency (FPE) and obtaining 95% survival for juvenile salmon passing Bonneville Dam. Major passage routes include 10 turbines and a sluiceway at Powerhouse 1 (B1), an 18-bay spillway, and eight turbines and a sluiceway at Powerhouse 2 (B2). In this report, we present results of four studies related to juvenile salmonid passage at Bonneville Dam. The studies were conducted between April 15 and July 15, 2004, encompassing most of the spring and summer migrations. Studies included evaluations of (1) Project fish passage efficiency and other major passage metrics, (2) B2 fish guidance efficiency and gap loss, (3) smolt approach and fate at the B2 Corner Collector (B2CC), and (4) B2 vertical barrier screen head differential.

Immunomodulation and disease resistance in postyearling rainbow trout infected with Myxobolus cerebralis, the causative agent of whirling disease

Science.gov (United States)

Densmore, Christine L.; Ottinger, C.A.; Blazer, V.S.; Iwanowicz, L.R.; Smith, D.R.

2004-01-01

Myxobolus cerebralis, the myxosporean parasite that causes whirling disease, has a number of deleterious effects on its salmonid host. Although it is well established that juvenile salmonids in the active stages of whirling disease mount an immune response to the pathogen, the occurrence and longevity of any related immunomodulatory effects are unknown. In this study, postyearling rainbow trout Oncorhynchus mykiss infected with M. cerebralis were examined for leukocyte functions and for resistance to Yersinia ruckeri, a bacterial pathogen of salmonids. Compared with uninfected controls, M. cerebralis-infected fish showed lower proliferative lymphocyte responses to four mitogens (concanavalin A, pokeweed mitogen, phytohemagglutinin, and lipopolysaccharide). Conversely, M. cerebralis-infected fish displayed greater bactericidal activity of anterior kidney macrophages than did uninfected fish. After bath challenges with K. ruckeri, M. cerebralis-infected fish had slightly lower survival and a more rapid onset of mortality than did the control fish. Renal tissue and fecal samples from M. cerebralis-infected and uninfected survivors were cultured for the presence of K. ruckeri, and no difference in prevalence was noted between the two groups. Because immunomodulatory changes in the M. cerebralis-infected fish involved functional enhancement and suppression of different leukocyte populations, disease resistance among M. cerebralis-infected fish in the later stages of whirling disease will probably vary with the secondary pathogen and the nature of immune response the pathogen evokes.

Microscopic observation of symbiotic and aposymbiotic juvenile corals in nutrient-enriched seawater.

Science.gov (United States)

Tanaka, Yasuaki; Iguchi, Akira; Inoue, Mayuri; Mori, Chiharu; Sakai, Kazuhiko; Suzuki, Atsushi; Kawahata, Hodaka; Nakamura, Takashi

2013-03-15

Symbiotic and aposymbiotic juvenile corals, which were grown in the laboratory from the gametes of the scleractinian coral Acropora digitifera and had settled down onto plastic culture plates, were observed with a microscope under different nutrient conditions. The symbiotic corals successfully removed the surrounding benthic microalgae (BMA), whereas the aposymbiotic corals were in close physical contact with BMA. The areal growth rate of the symbiotic corals was significantly higher than that of the aposymbiotic corals. The addition of nutrients to the culture seawater increased the chlorophyll a content in the symbiotic coral polyps and enhanced the growth of some of the symbiotic corals, however the average growth rate was not significantly affected, most likely because of the competition with BMA. The comparison between the symbiotic and aposymbiotic juvenile corals showed that the establishment of a symbiotic association could be imperative for post-settlement juvenile corals to survive in high-nutrient seawater. Copyright © 2012 Elsevier Ltd. All rights reserved.

Tagging, Mux, smolt, habitat and flow data - Movement and Survival of Juvenile Salmonids in Small Streams

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National Oceanic and Atmospheric Administration, Department of Commerce — This project is part of the Washington State Intensively Monitored Watershed (IMW) Program. Using passive inductive transponder (PIT) tags and remote stationary...

The Development of Four Leading Principles of the Convention on the Rights of the Child in Vietnam´s Juvenile Justice

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Duc Nguyen

2017-01-01

Full Text Available The paper sheds light on the latest development of four CRC principles in the administration of Vietnam’s juvenile justice after the recent amendment of the Penal Code and Criminal Procedural Code of Vietnam. It also assesses the compatibility of the Vietnamese juvenile justice system compared to international standards elaborated by the CRC Committee. At the same time, certain issues are raised regarding the implementation of such principles in practice. Finally, concluding remarks will be provided together with recommendations on how to develop the juvenile justice system in Vietnam. Keywords: Vietnam’s juvenile justice; Children’s rights; CRC leading principles; juvenile offenders; the rights of the child; non-discrimination; best interests of the child; children’s right to life; survival and development; children’s right to be heard.

Development of a new method for the determination of residues of the neonictinoid insecticide imidacloprid in juvenile Chinook (Oncorhynchus tyshawytscha) using ELISA detection

Science.gov (United States)

Frew, John A.; Grue, Christian E.

2012-01-01

The neonicotinoid insecticide imidacloprid (IMI) has been proposed as an alternative to carbaryl for controlling indigenous burrowing shrimp on commercial oyster beds in Willapa Bay and Grays Harbor, Washington. A focus of concern over the use of this insecticide in an aquatic environment is the potential for adverse effects from exposure to non-target species residing in the Bay, such as juvenile Chinook (Oncorhynchus tshawytscha) and cutthroat trout (O. clarki). Federal registration and State permiting approval for the use of IMI will require confirmation that the compound does not adversely impact these salmonids following field applications. This will necessitate an environmental monitoring program for evaluating exposure in salmonids following the treatment of beds. Quantification of IMI residues in tissue can be used for determining salmonid exposure to the insecticide. Refinement of an existing protocol using liquid-chromatography mass spectrometry (LC-MS) detection would provide the low limits of quantification, given the relatively small tissue sample sizes, necessary for determining exposure in individual fish. Such an approach would not be viable for the environmental monitoring effort in Willapa Bay and Grays Harbor due to the high costs associated with running multiple analyses, however. A new sample preparation protocol was developed for use with a commercially available enzyme-linked immunosorbent assay (ELISA) for the quantification of IMI, thereby providing a low-cost alternative to LC-MS for environmental monitoring in Willapa Bay and Grays Harbor. Extraction of the analyte from the salmonid brain tissue was achieved by Dounce homogenization in 4.0 mL of 20.0 mM Triton X-100, followed by a 6 h incubation at 50–55 °C. Centrifugal ultrafiltration and reversed phase solid phase extraction were used for sample cleanup. The limit of quantification for an average 77.0 mg whole brain sample was calculated at 18.2 μg kg-1 (ppb) with an average

Metro Multnomah Wetlands - Multnomah Channel Wetland Restoration Monitoring Project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The Multnomah Channel Wetland Restoration Monitoring Project characterizes wetlands use by juvenile salmonids and other fishes in the Multnomah Channel Marsh Natural...

Exercise training reveals trade-offs between endurance performance and immune function, but does not influence growth, in juvenile lizards.

Science.gov (United States)

Husak, Jerry F; Roy, Jordan C; Lovern, Matthew B

2017-04-15

Acquired energetic resources allocated to a particular trait cannot then be re-allocated to a different trait. This often results in a trade-off between survival and reproduction for the adults of many species, but such a trade-off may be manifested differently in juveniles not yet capable of reproduction. Whereas adults may allocate resources to current and/or future reproduction, juveniles can only allocate to future reproduction. Thus, juveniles should allocate resources toward traits that increase survival and their chances of future reproductive success. We manipulated allocation of resources to performance, via endurance exercise training, to examine trade-offs among endurance capacity, immune function and growth in juvenile green anole lizards. We trained male and female captive anoles on a treadmill for 8 weeks, with increasing intensity, and compared traits with those of untrained individuals. Our results show that training enhanced endurance capacity equally in both sexes, but immune function was suppressed only in females. Training had no effect on growth, but males had higher growth rates than females. Previous work showed that trained adults have enhanced growth, so juvenile growth is either insensitive to stimulation with exercise, or they are already growing at maximal rates. Our results add to a growing body of literature indicating that locomotor performance is an important part of life-history trade-offs that are sex and age specific. © 2017. Published by The Company of Biologists Ltd.

Juvenile Arthritis

Science.gov (United States)

Juvenile arthritis (JA) is arthritis that happens in children. It causes joint swelling, pain, stiffness, and loss of motion. It can affect any joint, but ... of JA that children get is juvenile idiopathic arthritis. There are several other forms of arthritis affecting ...

Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary, Annual Report 2009

Energy Technology Data Exchange (ETDEWEB)

Diefenderfer, Heida L.; Johnson, Gary E.; Sather, Nichole K.; Skalski, John R.; Dawley, Earl M.; Coleman, Andre M.

2010-08-01

This report describes the 2009 research conducted under the U.S. Army Corps of Engineers (USACE or Corps) project EST-09-P-01, titled “Evaluation of Life History Diversity, Habitat Connectivity, and Survival Benefits Associated with Habitat Restoration Actions in the Lower Columbia River and Estuary.” The research was conducted by the Pacific Northwest National Laboratory, Marine Science Laboratory and Hydrology Group, in partnership with the University of Washington, School of Aquatic and Fishery Sciences, Columbia Basin Research, and Earl Dawley (NOAA Fisheries, retired). This Columbia River Fish Mitigation Program project, referred to as “Salmonid Benefits,” was started in FY 2009 to evaluate the state-of-the science regarding the ability to quantify the benefits to listed salmonids1 of habitat restoration actions in the lower Columbia River and estuary.

Effect of water flow rate and feed training on "pacamã" (Siluriforme: Pseudopimelodidae juvenile production

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R.K. Luz

2011-08-01

Full Text Available The effects of different water flow rates and feed training on the production of "pacamã" Lophiosilurus alexandri juveniles were evaluated. In the first experiment, nine day post-hatch larvae (n= 2,400 were stocked at a density of 5 larvae/L. Different water flow (F rates were tested: F1 = 180; F2 = 600; F3 = 1,300; and F4 = 2,600mL/min. Artemia nauplii were offered as food during the first 15 days of active feeding. In the second experiment for feed training, 720 juveniles (total length of 22.2mm were stocked at a density of 1.5 juveniles/L. A water flow rate similar to F1 was used. The use of extruded dry diet was tested, and feed training was done with and without other enhanced flavors (Artemia nauplii or Scott emulsion. The water flow rates did not influence the survival or growth of L. alexandri. Cannibalism occurred during feed training. The worst survival, specific growth rate and high mortality were found with the use of extruded dry diet, while similar values were registered with the different feed training diets used. Reduced water flow rate can be used to lower water consumption during larviculture and feed training of L. alexandri.

What Is Juvenile Arthritis?

Science.gov (United States)

... Initiative Breadcrumb Home Health Topics English Español Juvenile Arthritis Basics In-Depth Download Download EPUB Download PDF What is it? Points To Remember About Juvenile Arthritis Juvenile arthritis is the term used to describe ...

Optimising methods for community-based sea cucumber ranching: Experimental releases of cultured juvenile Holothuria scabra into seagrass meadows in Papua New Guinea

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Cathy Hair

2016-05-01

Full Text Available Hatchery-cultured juveniles of the commercial holothurian, sandfish (Holothuria scabra, were used for release experiments in a variety of marine habitats under traditional marine tenure near Kavieng, Papua New Guinea (PNG. Juveniles of approximately 4 g mean weight were released inside 100 m2 sea pens installed within seagrass meadows nearby partner communities, under the care of local ‘wardens’. Within each sea pen, varying levels of protection (free release, 1-day cage and 7-day cage were provided at release in order to determine if short-term predator exclusion improved survival. Ossicles of juvenile sandfish were tagged with different fluorochromes for each treatment and sandfish survival and growth was recorded after release. A range of biophysical parameters were recorded at the four sites. Contrary to expectations, short-term cage protection did not lead to higher survival at three sites, while a fourth site, despite meeting all considered criteria for suitable release habitat, experienced total loss of juveniles. There were significant differences in mean weight of juveniles between sites after four months. Multivariate analysis of biophysical factors clearly separated the sea pen habitats, strongly differentiating the best-performing site from the others. However, further research is needed to elucidate which biophysical or human factors are most useful in predicting the quality of potential sea ranch sites. Methods developed or refined through these trials could be used to establish pilot test plots at potential ranching sites to assess site suitability and provide guidance on the level of animal husbandry required before commencing community sea ranching operations in New Ireland Province, PNG. Keywords: Holothuria scabra, Mariculture, Sea pens, Predator exclusion, Principal components analysis, Biophysical variables

Performance of broodstock and hybrid juvenile of Egyptian and sangkuriang Clarias gariepinus strains

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Putri Zulfania

2016-02-01

Full Text Available ABSTRACT This study was conducted to evaluate reproduction of broodstock and intraspecific hybrid juvenile performance of Egyptian (M and sangkuriang (S strain African catfish Clarias gariepinus at nursery phase. Intraspecific hybridization of African catfish was carried out reciprocally (SM and MS and purebreed (SS and MM, each was with three replicates. Fish spawning was conducted by artificial fertilization, and larvae were reared at 1st, 2nd and 3rd nursery phases, subsequently. The results showed that broodstock performance (male and female of both strains were not significantly different (P>0.05 on all reproduction traits, except female’s gonadosomatic index. Fertilization and hatching rates of all hybrids were not significantly different (P>0.05. MM juvenile had higher growth performances than other juvenile hybrids. Heterosis of total length, standard length, and body weight were varied, whereas the survival showed positive heterosis. SM juvenile showed positive growth heterosis in 3rd nursery phase (total length, standard length, and body weight were 2.61%; 2.16%, and 4.79% respectively. Survival heterosis of MS juvenile (24.20% for total length; 103.13% for standard length and 11.62% body weight was higher than SM juvenile (6.86%; 48.57%, and 3.09% on all nursery phases Keywords: African catfish, intraspecific hybridization, growth, survival, heterosis  ABSTRAK Penelitian ini dilakukan untuk menguji performa reproduksi induk dan benih hasil hibridisasi intraspesifik ikan lele Afrika Clarias gariepinus strain Sangkuriang (S dan Mesir (M pada fase pendederan. Hibridisasi intraspesifik ikan lele Afrika dilakukan secara resiprokal (SM dan MS dan galur murni (SS dan MM masing-masing dengan tiga ulangan. Pemijahan dilakukan secara buatan dan larva yang dihasilkan dipelihara pada fase pendederan pertama, kedua, dan ketiga. Hasil penelitian menunjukkan bahwa performa induk ikan lele jantan dan betina pada kedua strain tidak berbeda

Barriers, invasion, and conservation of native salmonids in coldwater streams [Box 18.2

Science.gov (United States)

Bruce Rieman; Michael Young; Kurt Fausch; Jason Dunham; Douglas Peterson

2010-01-01

Habitat loss and fragmentation are threats to persistence of many native fish populations. Invading nonnative species that may restrict or displace native species are also important. These two issues are particularly relevant for native salmonids that are often limited to remnant habitats in cold, headwater streams. On the surface, reversing threats to native fishes...

Chronic toxicity of copper and ammonia to juvenile freshwater mussels (Unionidae)

Science.gov (United States)

Wang, N.; Ingersoll, C.G.; Greer, I.E.; Hardesty, D.K.; Ivey, C.D.; Kunz, J.L.; Brumbaugh, W.G.; Dwyer, F.J.; Roberts, A.D.; Augspurger, T.; Kane, C.M.; Neves, R.J.; Barnhart, M.C.

2007-01-01

The objectives of the present study were to develop methods for conducting chronic toxicity tests with juvenile mussels under flow-through conditions and to determine the chronic toxicity of copper and ammonia to juvenile mussels using these methods. In two feeding tests, two-month-old fatmucket (Lampsilis siliquoidea) and rainbow mussel (Villosa iris) were fed various live algae or nonviable algal mixture for 28 d. The algal mixture was the best food resulting in high survival (???90%) and growth. Multiple copper and ammonia toxicity tests were conducted for 28 d starting with two-month-old mussels. Six toxicity tests using the algal mixture were successfully completed with a control survival of 88 to 100%. Among copper tests with rainbow mussel, fatmucket, and oyster mussel (Epioblasma capsaeformis), chronic value ([ChV], geometric mean of the no-observed-effect concentration and the lowest-observed-effect concentration) ranged from 8.5 to 9.8 ??g Cu/L for survival and from 4.6 to 8.5 ??g Cu/L for growth. Among ammonia tests with rainbow mussel, fatmucket, and wavy-rayed lampmussel (L. fasciola), the ChV ranged from 0.37 to 1.2 mg total ammonia N/L for survival and from 0.37 to 0.67 mg N/L for growth. These ChVs were below the U.S. Environmental Protection Agency 1996 chronic water quality criterion (WQC) for copper (15 ??g/L; hardness 170 mg/L) and 1999 WQC for total ammonia (1.26 mg N/L; pH 8.2 and 20??C). Results indicate that toxicity tests with two-month-old mussels can be conducted for 28 d with >80% control survival; growth was frequently a more sensitive endpoint compared to survival; and the 1996 chronic WQC for copper and the 1999 chronic WQC for total ammonia might not be adequately protective of the mussel species tested. However, a recently revised 2007 chronic WQC for copper based on the biotic ligand model may be more protective in the water tested. ?? 2007 SETAC.

Impacts of food availability and pCO2 on planulation, juvenile survival, and calcification of the azooxanthellate scleractinian coral Balanophyllia elegans

Science.gov (United States)

Crook, E. D.; Cooper, H.; Potts, D. C.; Lambert, T.; Paytan, A.

2013-11-01

Ocean acidification, the assimilation of atmospheric CO2 by the oceans that decreases the pH and CaCO3 saturation state (Ω) of seawater, is projected to have severe adverse consequences for calcifying organisms. While strong evidence suggests calcification by tropical reef-building corals containing algal symbionts (zooxanthellae) will decline over the next century, likely responses of azooxanthellate corals to ocean acidification are less well understood. Because azooxanthellate corals do not obtain photosynthetic energy from symbionts, they provide a system for studying the direct effects of acidification on energy available for calcification. The solitary azooxanthellate orange cup coral Balanophyllia elegans often lives in low-pH, upwelled waters along the California coast. In an 8-month factorial experiment, we measured the effects of three pCO2 treatments (410, 770, and 1220 μatm) and two feeding frequencies (3-day and 21-day intervals) on "planulation" (larval release) by adult B. elegans, and on the survival, skeletal growth, and calcification of newly settled juveniles. Planulation rates were affected by food level but not pCO2. Juvenile mortality was highest under high pCO2 (1220 μatm) and low food (21-day intervals). Feeding rate had a greater impact on calcification of B. elegans than pCO2. While net calcification was positive even at 1220 μatm (~3 times current atmospheric pCO2), overall calcification declined by ~25-45%, and skeletal density declined by ~35-45% as pCO2 increased from 410 to 1220 μatm. Aragonite crystal morphology changed at high pCO2, becoming significantly shorter but not wider at 1220 μatm. We conclude that food abundance is critical for azooxanthellate coral calcification, and that B. elegans may be partially protected from adverse consequences of ocean acidification in habitats with abundant heterotrophic food.

Exposure of juvenile Danio rerio to aged TiO₂ nanomaterial from sunscreen.

Science.gov (United States)

Fouqueray, Manuela; Noury, Patrice; Dherret, Lysiane; Chaurand, Perrine; Abbaci, Khedidja; Labille, Jerome; Rose, Jerome; Garric, Jeanne

2013-05-01

The toxicity of dietary exposure to artificially aged TiO₂ nanomaterial (T-Lite) used in sunscreen cream was studied on Danio rerio. Embryolarval assays were conducted to assess the effects of TiO₂ residues of nanomaterial (RNM) on fish early life stages. Juvenile fishes were exposed by the trophic route in two experiments. During the first experiment, juvenile fishes were exposed to TiO₂ RNM for 14 days by adding RNM to commercial fish food. The second one consisted in producing a trophic food chain. Pseudokirchneriella subcapitata algae, previously contaminated with TiO₂ RNM in growth medium, was used to feed Daphnia magna neonates over a 48-h period. Daphnia were used next to feed juvenile fishes for 7 days. Accumulation of Ti, life traits (survival and growth) and biochemical parameters such as energy reserves, digestive (trypsin, esterase, cellulose and amylase) and antioxidant (superoxide dismutase and catalase) enzyme activity were measured at the end of exposures. As expected in the receiving aquatic system, TiO2 RNM at low concentrations caused a low impact on juvenile zebrafish. A slight impact on the early life stage of zebrafish with premature hatching was observed, and this effect appeared mainly indirect, due to possible embryo hypoxia. When juvenile fish are exposed to contaminated food, digestive enzyme activity indicated a negative effect of TiO₂ RNM. Digestive physiology was altered after 14 days of exposure and seemed to be an indirect target of TiO₂ RNM when provided by food.

Juvenile Firesetting.

Science.gov (United States)

Peters, Brittany; Freeman, Bradley

2016-01-01

Juvenile firesetting is a significant cause of morbidity and mortality in the United States. Male gender, substance use, history of maltreatment, interest in fire, and psychiatric illness are commonly reported risk factors. Interventions that have been shown to be effective in juveniles who set fires include cognitive behavior therapy and educational interventions, whereas satiation has not been shown to be an effective intervention. Forensic assessments can assist the legal community in adjudicating youth with effective interventions. Future studies should focus on consistent assessment and outcome measures to create more evidence for directing evaluation and treatment of juvenile firesetters. Copyright © 2016 Elsevier Inc. All rights reserved.

Movement patterns, habitat use, and survival of Lahontan cutthroat trout in the Truckee River

Science.gov (United States)

Alexiades, Alexander V.; Peacock, Mary M.; Al-Chokhachy, Robert K.

2012-01-01

Habitat fragmentation, hybridization, and competition with nonnative salmonids are viewed as major threats to Lahontan cutthroat trout Oncorhynchus clarkii henshawi. Understanding Lahontan cutthroat trout behavior and survival is a necessary step in the reintroduction and establishment of naturally reproducing populations of Lahontan cutthroat trout. We used weekly radiotelemetry monitoring to examine movement patterns, habitat use, and apparent survival of 42 hatchery-reared Lahontan cutthroat trout in a 16.5-km stretch of the Truckee River, Nevada, across three reaches separated by barriers to upstream movement. We found differences in total movement distances and home range sizes of fish in different reaches within our study area. Fish used pool habitats more than fast water habitats in all reaches. Time of year, stream temperature, and fish standard length covariates had the strongest relationship with apparent survival. Monthly apparent survival was lowest in January, which coincided with the lowest flows and temperatures during the study period. Our results verify the mobility of Lahontan cutthroat trout and indicate that conditions during winter may limit the survival and reintroduction success in the portions of the Truckee River evaluated in this study.

Spatial distribution of the stomach weights of juvenile anchovy (Engraulis encrasicolus L.) in the Bay of Biscay

KAUST Repository

Bachiller, Eneko; Cotano, Unai; Boyra, Guillermo; Irigoien, Xabier

2012-01-01

Previous studies have shown that the survival of larval and juvenile anchovy off the continental shelf in the Bay of Biscay is not significantly different from that observed on the shelf, even though the food concentration is significantly higher

Spatial and begging behaviours of juvenile Tawny Owls (Strix aluco) from fledging to independence under contrasting food conditions

DEFF Research Database (Denmark)

Sunde, Peter; Naundrup, Pernille

2016-01-01

The post-fledging dependency period (PFDP: from fledging to cessation of parental care) is a critical yet poorly studied life history transition phase during which juveniles mature and develop skills for independence. We studied the spatial and vocal behaviour of radio-tagged juvenile Tawny Owls...... during the last 5 days before juvenile independence. Hence, juvenile Tawny Owls old enough to survive on their own invested heavily in begging, with no noticeable signs of increased hunting or exploration of potential settling areas outside the natal range, until they were no longer fed by their parents...... of the parental home range. The probability of begging per 20-min nocturnal observation period increased from 21 % at fledging to 80 % at independence during years of good food supply, but remained high (>82 %) in years of poor food supply. No change was observed in nocturnal movement distances or begging rates...

Effects of mannan oligosaccharide dietary supplementation on performances of the tropical spiny lobsters juvenile (Panulirus ornatus, Fabricius 1798).

Science.gov (United States)

Sang, Huynh Minh; Fotedar, Ravi

2010-03-01

The effects of dietary mannan oligosaccharide (MOS) (Bio-Mos, Alltech, USA) on the growth, survival, physiology, bacteria and morphology of the gut and immune response to bacterial infection of tropical rock lobsters (Panulirus ornatus) juvenile were investigated. Dietary inclusion level of MOS at 0.4% was tested against the control diet (trash fish) without MOS inclusion. At the end of 56 days of rearing period, a challenged test was also conducted to evaluate the bacterial infection resistant ability of the lobsters fed the two diets. Lobster juvenile fed MOS diet attained 2.86 +/- 0.07 g of total weigh and 66.67 +/- 4.76% survival rate which were higher (P lobsters fed control diet (2.35 +/- 0.14 g total weight and 54.76 +/- 2.38% survival rate, respectively) thus providing the higher (P lobsters fed MOS diet. Physiological condition indicators such as wet tail muscle index (Tw/B), wet hepatosomatic index (Hiw) and dry tail muscle index (Td/B) of the lobsters fed MOS supplemented diet were higher (P lobsters fed the control diet. Bacteria in the gut (both total aerobic and Vibrio spp.) and gut's absorption surface indicated by the internal perimeter/external perimeter ratio were also higher (P lobsters were fed MOS diet. Lobsters fed MOS diet were in better immune condition showed by higher THC and GC, and lower bacteraemia. Survival, THC, GC were not different among the lobsters fed either MOS or control diet after 3 days of bacterial infection while bacteraemia was lower in the lobsters fed MOS diet. After 7 days of bacterial infection the lobsters fed MOS diet showed higher survival, THC, GC and lower bacteraemia than the lobsters fed the control diet. The experimental trial demonstrated the ability of MOS to improve the growth performance, survival, physiological condition, gut health and immune responses of tropical spiny lobsters juveniles. Copyright 2009 Elsevier Ltd. All rights reserved.

Tabular statistical summay of data analysis - Calawah River Riverscape Study

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — The objective of this study was to identify the patterns of juvenile salmonid distribution and relative abundance in relation to habitat correlates. It is the first...

Umatilla Basin Natural Production Monitoring and Evaluation; 1995-1996 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Contor, Craig R.; Kissner, Paul; Volkman, Jed [Confederated Tribes of the Umatilla Indian Reservation, Pendleton, OR (United States). Dept. of Natural Resources

1997-08-01

This report summarizes the activities of the Umatilla Basin Natural Production Monitoring and Evaluation Project (UBNPME) from September 30, 1995 to September 29, 1996. This program was funded by Bonneville Power Administration and was managed under the Fisheries Program, Department of Natural Resources, Confederated Tribes of the Umatilla Indian Reservation. The goal was to evaluate the implementation of the Umatilla River Basin fisheries restoration plan with respect to natural production, adult passage, and tribal harvest. An estimated 56.1 river miles (RM) of habitat was inventoried on the lower Umatilla River (RM 0--56.1) from June 4, to August 1, 1996. The majority of the lower River was found to be too polluted and physically altered to provide suitable rearing or migration habitat for salmonids during the summer. High water temperatures, irrigation withdrawals, altered channels, and urban and agricultural pollution all contributed to degrade the lower Umatilla River. Small springs provided cooler waters and created small areas that were suitable for salmonid rearing. The river below the mouth of Mckay Creek (RM 27.2 to 50.6) was also cooler and more suitable to salmonid rearing when water was released from Mckay Dam. Two hundred sixty-three of 1,832 (14.4%) habitat units were electrofished from June 19 to August 29, 1996. The number of natural juvenile salmonids captured between RM 1.5--52.4 follow: (1) 141 juvenile steelhead (including resident rainbow trout; Oncoryhnchus mykiss), (2) 13 mountain whitefish (Prosopium williamsoni, including adults), (3) four chinook salmon (O. tshawytscha), and (4) two coho salmon (O. kisutch). The expanded population estimate for the areas surveyed was 2,445 salmonids. Mean density was 0.147 salmonids/100 square meter. Mean density of fast water habitat types was 4.5 times higher than slow water types (0.358 and 0.079 s/100 m{sup 2}).

Umatilla Basin natural production monitoring and evaluation. Annual report 1995-1996

International Nuclear Information System (INIS)

Contor, C.R.; Hoverson, E.; Kissner, P.; Volkman, J.

1997-08-01

This report summarizes the activities of the Umatilla Basin Natural Production Monitoring and Evaluation Project (UBNPME) from September 30, 1995 to September 29, 1996. This program was funded by Bonneville Power Administration and was managed under the Fisheries Program, Department of Natural Resources, Confederated Tribes of the Umatilla Indian Reservation. The goal was to evaluate the implementation of the Umatilla River Basin fisheries restoration plan with respect to natural production, adult passage, and tribal harvest. An estimated 56.1 river miles (RM) of habitat was inventoried on the lower Umatilla River (RM 0--56.1) from June 4, to August 1, 1996. The majority of the lower River was found to be too polluted and physically altered to provide suitable rearing or migration habitat for salmonids during the summer. High water temperatures, irrigation withdrawals, altered channels, and urban and agricultural pollution all contributed to degrade the lower Umatilla River. Small springs provided cooler waters and created small areas that were suitable for salmonid rearing. The river below the mouth of Mckay Creek (RM 27.2 to 50.6) was also cooler and more suitable to salmonid rearing when water was released from Mckay Dam. Two hundred sixty-three of 1,832 (14.4%) habitat units were electrofished from June 19 to August 29, 1996. The number of natural juvenile salmonids captured between RM 1.5--52.4 follow: (1) 141 juvenile steelhead (including resident rainbow trout; Oncoryhnchus mykiss), (2) 13 mountain whitefish (Prosopium williamsoni, including adults), (3) four chinook salmon (O. tshawytscha), and (4) two coho salmon (O. kisutch). The expanded population estimate for the areas surveyed was 2,445 salmonids. Mean density was 0.147 salmonids/100 square meter. Mean density of fast water habitat types was 4.5 times higher than slow water types (0.358 and 0.079 s/100 m 2 )

Annual elk calf survival in a multiple carnivore system

Science.gov (United States)

Eacker, Daniel R.; Hebblewhite, Mark; Proffitt, Kelly M.; Jimenez, Benjamin S.; Mitchell, Michael S.; Robinson, Hugh S.

2016-01-01

The realized effect of multiple carnivores on juvenile ungulate recruitment may depend on the carnivore assemblage as well as compensation from forage and winter weather severity, which may mediate juvenile vulnerability to predation in ungulates. We used a time-to-event approach to test for the effects of risk factors on annual elk (Cervus canadensis) calf survival and to estimate cause-specific mortality rates for 2 elk populations in adjacent study areas in the southern Bitterroot Valley, Montana, USA, during 2011–2014. We captured and radio-tagged 286 elk calves: 226 neonates, and 60 6-month-old calves. Summer survival probability was less variable than winter (P = 0.12) and averaged 0.55 (95% CI = 0.47–0.63), whereas winter survival varied more than summer and significantly across study years (P = 0.003) and averaged 0.73 (95% CI = 0.64–0.81). During summer, elk calf survival increased with biomass of preferred forage biomass, and was slightly lower following winters with high precipitation; exposure to mountain lion (Puma concolor) predation risk was unimportant. In contrast, during winter, we found that exposure to mountain lion predation risk influenced survival, with a weak negative effect of winter precipitation. We found no evidence that forage availability or winter weather severity mediated vulnerability to mountain lion predation risk in summer or winter (e.g., an interaction), indicating that the effect of mountain lion predation was constant regardless of spatial variation in forage or weather. Mountain lions dominated known causes of elk calf mortality in summer and winter, with estimated cause-specific mortality rates of 0.14 (95% CI = 0.09–0.20) and 0.12 (95% CI = 0.07–0.18), respectively. The effect of carnivores on juvenile ungulate recruitment varies across ecological systems depending on relative carnivore densities. Mountain lions may be the most important carnivore for ungulates, especially where grizzly

Umatilla River Fish Passage Operations Program, 2002-2003 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Bronson, James P. (Confederated Tribes of the Umatilla Indian Reservation, Department of Natural Resources, Pendleton, OR); Duke, Bill B. (Oregon Department of Fish and Wildlife, Pendleton, OR)

2004-03-01

Threemile Falls Dam (Threemile Dam), located near the town of Umatilla, is the major collection and counting point for adult salmonids returning to the Umatilla River. Returning salmon and steelhead were enumerated at Threemile Dam from August 17, 2002 to September 29, 2003. A total of 3,080 summer steelhead (Oncorhynchus mykiss); 1716 adult, 617 jack, and 1,709 subjack fall chinook (O. tshawytscha); 3,820 adult and 971 jack coho (O. kisutch); and 3,607 adult and 135 jack spring chinook (O. tshawytscha) were counted. All fish were enumerated at the east bank facility. Of the fish counted, 6 summer steelhead and 330 adult and 49 jack spring chinook were hauled upstream from Threemile Dam. There were 2,882 summer steelhead; 1161 adult, 509 jack and 1,546 subjack fall chinook; 3,704 adult and 915 jack coho; and 2,406 adult and 31 jack spring chinook either released at, or allowed to volitionally migrate past, Threemile Dam. Also, 109 summer steelhead; 532 adult and 32 jack fall chinook; and 560 adult and 28 jack spring chinook were collected for brood. In addition, 282 spring chinook were collected for the outplanting efforts in the Walla Walla Basin. The Westland Canal juvenile facility (Westland), located near the town of Echo at rivermile (RM) 27, is the major collection point for outmigrating juvenile salmonids and steelhead kelts. The canal was open for 159 days between January 27 and July 4, 2003. During that period, fish were bypassed back to the river 145 days and were trapped 11 days. An estimated 205 pounds of juvenile fish were transported from Westland to the Umatilla River boat ramp (RM 0.5). Approximately 82% of the juveniles transported were salmonids. No steelhead kelts were hauled from Westland this year. The Threemile Dam west bank juvenile bypass was opened on September 16, 2002. and continued until November 1, 2002. The bypass was reopened March 3, 2003 and ran until July 3, 2003. The juvenile trap was operated by the Umatilla Passage Evaluation

Effect of salinity on survival, growth and biochemical parameters in juvenile Lebranch mullet Mugil liza (Perciformes: Mugilidae

Directory of Open Access Journals (Sweden)

Viviana Lisboa

Full Text Available Teleost fish growth may be improved under isosmotic condition. Growth and metabolic performance of juvenile Mugil liza (isosmotic point: 12‰ were evaluated after 40 days in different salinities (0, 6, 12 and 24‰. Tests were performed in quadruplicate (30 fish/tank; 0.48 ± 0.1 g body weight; 3.27 ± 0.1 cm total length under controlled water temperature (28.2 ± 0.1ºC and oxygen content (>90% saturation. Fish were fed on artificial diet (50% crude protein four times a day until apparent satiation. Results showed that salinity influenced juvenile mullet growth. Fish reared at salinity 24‰ grew better than those maintained in freshwater (salinity 0‰. Gill Na+,K+-ATPase activity and whole body oxygen consumption showed an U-shape-type response over the range of salinities tested, with the lower values being observed at the intermediate salinities. Although no significant difference was observed in liver glycogen content at different salinities, it tended to augment with increasing salinity. These findings indicate that energy demand for osmorregulation in juvenile M. liza can be minimized under isosmotic condition. However, the amount of energy spared is not enough to improve fish growth. Results also suggest that M. liza is able to alternate between different energy-rich substrates during acclimation to environmental salinity.

Invasion versus isolation: Trade-offs in managing native salmonids with barriers to upstream movement

Science.gov (United States)

Kurt D. Fausch; Bruce E. Rieman; Jason B. Dunham; Michael K. Young; Douglas P. Peterson

2009-01-01

Conservation biologists often face the trade-off that increasing connectivity in fragmented landscapes to reduce extinction risk of native species can foster invasion by non-native species that enter via the corridors created, which can then increase extinction risk. This dilemma is acute for stream fishes, especially native salmonids, because their populations are...

Development of field-based models of suitable thermal regimes for interior Columbia Basin salmonids

Science.gov (United States)

Jason B. Dunham; Bruce Rieman; Gwynne Chandler

2001-01-01

This report describes results of research sponsored through an interagency agreement between the U.S. Forest Service Rocky Mountain Research Station and U.S. Environmental Protection Agency (Interagency Agreement #00-IA-11222014-521). The primary objectives of this research included 1) develop models relating occurrence of two threatened inland salmonid fishes to...

Modes of salmonid MHC class I and II evolution differ from the primate paradigm

NARCIS (Netherlands)

Shum, B.P.; Guethlein, L.; Flodin, L.R.; Adkison, M.A.; Hedrick, R.P.; Nehring, R.B.; Stet, R.J.M.; Secombes, C.; Parham, P.

2001-01-01

Rainbow trout (Oncorhynchus mykiss) and brown trout (Salmo trutta) represent two salmonid genera separated for 15-20 million years. cDNA sequences were determined for the classical MHC class I heavy chain gene UBA and the MHC class II β-chain gene DAB from 15 rainbow and 10 brown trout. Both genes

Juvenile Court Statistics - 1972.

Science.gov (United States)

Office of Youth Development (DHEW), Washington, DC.

This report is a statistical study of juvenile court cases in 1972. The data demonstrates how the court is frequently utilized in dealing with juvenile delinquency by the police as well as by other community agencies and parents. Excluded from this report are the ordinary traffic cases handled by juvenile court. The data indicate that: (1) in…

Juvenile Court Statistics, 1974.

Science.gov (United States)

Corbett, Jacqueline; Vereb, Thomas S.

This report presents information on juvenile court processing of youth in the U.S. during 1974. It is based on data gathered under the National Juvenile Court Statistical Reporting System. Findings can be summarized as follows: (1) 1,252,700 juvenile delinquency cases, excluding traffic offenses, were handled by courts in the U.S. in 1974; (2) the…

Freezing avoidance mechanisms in juveniles of giant rosette plants of the genus Espeletia

Science.gov (United States)

García-Varela, Sonia; Rada, Fermín

2003-07-01

Along soil-air gradients in tropical high mountains, plants growing at soil level tolerate frost while those growing well above ground, including all species in the genus Espeletia, use freezing avoidance mechanisms to survive low nighttime temperatures. The question that arises and the objective of this work were: What are the low temperature resistance mechanisms in giant rosettes when they are within the juvenile stages, i.e. closer to the ground? Juveniles of Espeletia spicata and Espeletia timotensis, dominant plants of the high Venezuelan Andes, were chosen for this study. To determine resistance mechanisms for these species, air and leaf temperatures were recorded in the field in 24 h cycles, while thermal analysis and injury temperature were determined in the laboratory. Both E. spicata and E. timotensis juveniles depend on avoidance mechanisms through a high supercooling capacity, permitting leaves to resist low nighttime temperatures. Minimum leaf temperatures were -4.9 and -5.1 °C, for E. spicata and E. timotensis, respectively, occurring during the dry season. Ice formation occurred at -14.3 and -15.3 °C for E. spicata and E. timotensis, respectively. Injury occurred at approximately -15 °C in both species. Low temperature resistance mechanisms in juveniles are similar to those in adult plants.

Facultative anadromy in salmonids: linking habitat, individual life history decisions, and population-level consequences

Science.gov (United States)

Steven F. Railsback; Bret C. Harvey; Jason L. White

2014-01-01

Modeling and management of facultative anadromous salmonids is complicated by their ability to select anadromous or resident life histories. Conventional theory for this behavior assumes individuals select the strategy offering highest expected reproductive success but does not predict how population-level consequences such as a stream’s smolt production emerge from...

Resistance of juveniles of the Mediterranean pen shell, (Pinna nobilis) to hypoxia and interaction with warming

KAUST Repository

Basso, Lorena

2015-05-01

Low oxygen zones in coastal and open ecosystems have expanded in recent decades, a trend that will accelerate with climatic warming. Exposure of nearshore animals to hypoxic waters and increasing temperature may be stressful and lead to impaired physiological performance. Here, we evaluate the effect of low oxygen concentrations in interaction with increased temperature on juveniles of a large Mediterranean bivalve, Pinna nobilis. We examine the response of survival and oxygen consumption of juveniles placed in water with normal and low oxygen concentrations (100% and 40%, respectively) along an increased temperature gradient (24, 26, 28 and 30°C) during 4 days. To our knowledge, this is the first study on hypoxia and its combined effect with temperature on juveniles of this species. We show that the two stressors alone or in combination do not influence the physiological performance of juveniles for short periods (4 days). This result stands apart from a general trend pointing at ocean warming as additional stressor that could increase the vulnerability of benthic macrofauna to reduced oxygen concentrations. © 2015 Elsevier Ltd.

Resistance of juveniles of the Mediterranean pen shell, (Pinna nobilis) to hypoxia and interaction with warming

KAUST Repository

Basso, Lorena; Hendriks, Iris E.; Duarte, Carlos M.

2015-01-01

Low oxygen zones in coastal and open ecosystems have expanded in recent decades, a trend that will accelerate with climatic warming. Exposure of nearshore animals to hypoxic waters and increasing temperature may be stressful and lead to impaired physiological performance. Here, we evaluate the effect of low oxygen concentrations in interaction with increased temperature on juveniles of a large Mediterranean bivalve, Pinna nobilis. We examine the response of survival and oxygen consumption of juveniles placed in water with normal and low oxygen concentrations (100% and 40%, respectively) along an increased temperature gradient (24, 26, 28 and 30°C) during 4 days. To our knowledge, this is the first study on hypoxia and its combined effect with temperature on juveniles of this species. We show that the two stressors alone or in combination do not influence the physiological performance of juveniles for short periods (4 days). This result stands apart from a general trend pointing at ocean warming as additional stressor that could increase the vulnerability of benthic macrofauna to reduced oxygen concentrations. © 2015 Elsevier Ltd.

Spatial match-mismatch between juvenile fish and prey provides a mechanism for recruitment variability across contrasting climate conditions in the eastern Bering Sea.

Science.gov (United States)

Siddon, Elizabeth Calvert; Kristiansen, Trond; Mueter, Franz J; Holsman, Kirstin K; Heintz, Ron A; Farley, Edward V

2013-01-01

Understanding mechanisms behind variability in early life survival of marine fishes through modeling efforts can improve predictive capabilities for recruitment success under changing climate conditions. Walleye pollock (Theragra chalcogramma) support the largest single-species commercial fishery in the United States and represent an ecologically important component of the Bering Sea ecosystem. Variability in walleye pollock growth and survival is structured in part by climate-driven bottom-up control of zooplankton composition. We used two modeling approaches, informed by observations, to understand the roles of prey quality, prey composition, and water temperature on juvenile walleye pollock growth: (1) a bioenergetics model that included local predator and prey energy densities, and (2) an individual-based model that included a mechanistic feeding component dependent on larval development and behavior, local prey densities and size, and physical oceanographic conditions. Prey composition in late-summer shifted from predominantly smaller copepod species in the warmer 2005 season to larger species in the cooler 2010 season, reflecting differences in zooplankton composition between years. In 2010, the main prey of juvenile walleye pollock were more abundant, had greater biomass, and higher mean energy density, resulting in better growth conditions. Moreover, spatial patterns in prey composition and water temperature lead to areas of enhanced growth, or growth 'hot spots', for juvenile walleye pollock and survival may be enhanced when fish overlap with these areas. This study provides evidence that a spatial mismatch between juvenile walleye pollock and growth 'hot spots' in 2005 contributed to poor recruitment while a higher degree of overlap in 2010 resulted in improved recruitment. Our results indicate that climate-driven changes in prey quality and composition can impact growth of juvenile walleye pollock, potentially severely affecting recruitment variability.

Survival behaviour and virulence of the fish pathogen Vibrio ordalii in seawater microcosms.

Science.gov (United States)

Ruiz, Pamela; Poblete-Morales, Matías; Irgang, Rute; Toranzo, Alicia E; Avendaño-Herrera, Ruben

2016-06-15

Vibrio ordalii, the causative agent of atypical vibriosis, is a Gram-negative, motile, rod-shaped bacterium that severely affects the salmonid aquaculture industry. V. ordalii has been biochemically, antigenically and genetically characterized. However, studies on the survival behaviour of this bacterium in aquatic environments are scarce, and there is no information regarding its disease transmission and infectious abilities outside of the fish host or regarding water as a possible reservoir. The present study investigated the survival behaviour of V. ordalii Vo-LM-06 and Vo-LM-18 in sterile and non-sterile seawater microcosms. After a year in sterile seawater without nutrients, 1% of both V. ordalii strains survived (~10(3) colony-forming units ml(-1)), and long-term maintenance did not affect bacterial biochemical or genetic properties. Additionally, V. ordalii maintained for 60 d in sterile seawater remained infective in rainbow trout Oncorhynchus mykiss. However, after 2 d of natural seawater exposure, this bacterium became non-culturable, indicating that autochthonous microbiota may play an important role in survival. Recuperation assays that added fresh medium to non-sterile microcosms did not favour V. ordalii recovery on solid media. Our results contribute towards a better understanding of V. ordalii survival behaviour in seawater ecosystems.

THE STUDY OF FEATURES OF GUILT OF JUVENILE OFFENDERS IN THE CONTEXT OF JUVENILE JUSTICE

Directory of Open Access Journals (Sweden)

Natalija Vladimirovna Galkina

2015-08-01

Full Text Available The article is devoted to the results of empirical studies of the experiences of guilt of juvenile offenders in the context of juvenile justice where a minor appears as the subject of legal relations. Restorative approach of juvenile justice is based on an admission of guilt to the victim. In connection with it, the research of features of the guilt of minors who have committed an offence and the conditions for the development of the subjectivity will enhance understanding of the possibilities of restorative juvenile justice system in the prevention of juvenile delinquency.Thus, the results of empirical research presented in the article are important for determining of the psychological bases of realization of rehabilitation programs in the context of juvenile justice. In particular, the results are important for the organization and conduct of psychological work to overcome the psychological barriers in the behavior of juveniles having inherently maladaptive guilt and destructive psychological defense mechanisms.

Integrative demographic modeling reveals population level impacts of PCB toxicity to juvenile snapping turtles

International Nuclear Information System (INIS)

Salice, Christopher J.; Rowe, Christopher L.; Eisenreich, Karen M.

2014-01-01

A significant challenge in ecotoxicology and risk assessment lies in placing observed contaminant effects in a meaningful ecological context. Polychlorinated biphenyls (PCBs) have been shown to affect juvenile snapping turtle survival and growth but the ecological significance of these effects is difficult to discern without a formal, population-level assessment. We used a demographic matrix model to explore the potential population-level effects of PCBs on turtles. Our model showed that effects of PCBs on juvenile survival, growth and size at hatching could translate to negative effects at the population level despite the fact that these life cycle components do not typically contribute strongly to population level processes. This research points to the utility of using integrative demographic modeling approaches to better understand contaminant effects in wildlife. The results indicate that population-level effects are only evident after several years, suggesting that for long-lived species, detecting adverse contaminant effects could prove challenging. -- Highlights: • Previous studies have shown the PCBs can impact juvenile snapping turtles. • We used a demographic model of turtles to evaluate population-level PCB effects. • PCB effects on turtles may translate to negative population responses. • Long-term monitoring is needed to detect contaminant effects on natural turtle populations. • Demographic models can improve our understanding contaminant ecotoxicity. -- A demographic model was used to show that PCB induced effects on young snapping turtles can result in adverse effects at the population level

Juvenile Justice in Mexico

Directory of Open Access Journals (Sweden)

Martha Frías Armenta

2014-08-01

Full Text Available The first tribunal in Mexico was established in the central state of San Luis Potosi in 1926. The Law Regarding Social Prevention and Juvenile Delinquency for the Federal District and Mexican territories was promulgated in 1928. In 2005, Article 18 of the Mexican Constitution was modified to establish a comprehensive system (“Sistema Integral de justicia” in Spanish of justice for juveniles between 12 and 18 years old who had committed a crime punishable under criminal law. Its objective was to guarantee juveniles all the due process rights established for adults, in addition to the special ones recognized for minors. The constitutional reform also provides a framework that includes special tribunals as well as alternative justice options for juveniles. With these reforms, institutionalization of minors was to be considered an extreme measure applicable only to felonies and to juveniles older than 14. In 2006, all states within the Mexican federation enacted the “Law of justice for adolescents”. This system, at both the federal and state levels, formalizes a new global paradigm with regard to the triangular relationship between children, the State and the Law. It recognizes that children are also bearers of the inherent human rights recognized for all individuals, instead of simply objects in need of protection. However, despite formally aligning Mexican juvenile justice law with the Convention on the Rights of the Child (CRC, issues of actual substantive rights remained and new ones have appeared. For example, juveniles younger than 14 who have not committed a felony are released from institutions without any rehabilitation or treatment options, and alternative forms of justice were included without evaluating their possibilities of application or their conditions for success. In addition, the economic status of most juvenile detainees continues to be one of the most important determining factors in the administration of justice

Isolated Juvenile Xanthogranuloma in Thoracic Spine: Intraoperative Cytological Diagnosis of a Rare Presentation

Directory of Open Access Journals (Sweden)

Shashi Singhvi

2014-06-01

Full Text Available Juvenile Xanthogranulomas (JXG are benign proliferative disorders of non-Langerhans histiocytes, which present in children as multiple, self-limited, cutaneous lesions. The extracutaneous manifestations of JXG are uncommon, and isolated JXG involving the spinal column is extremely rare. We report here a case of isolated juvenile xanthogranuloma in thoracic spine correctly diagnosed intraoperatively on crush smear cytology and later confirmed by histopathological and immunohistochemical studies. This case report draws attention to the fact that isolated xanthogranuloma should be considered among possible diagnoses of spinal tumor in children. Also, since the long term survival depends on complete surgical resection, a correct intraoperative diagnosis is extremely important for optimal management and prognosis of the patient. [J Interdiscipl Histopathol 2014; 2(3.000: 158-162

Seasonal shift in the effects of predators on juvenile Atlantic salmon (Salmo salar) energetics

Science.gov (United States)

Darren M. Ward; Keith H. Nislow; Carol L. Folt; James Grant

2011-01-01

Predator effects on prey populations are determined by the number of prey consumed and effects on the traits of surviving prey. Yet the effects of predators on prey traits are rarely evaluated in field studies. We measured the effects of predators on energetic traits (consumption and growth rates) of juvenile Atlantic salmon (Salmo salar) in a...

Juvenile mammary papillomatosis; Papilomatosis juvenil mamaria

Energy Technology Data Exchange (ETDEWEB)

Alvarez, M.; Jimenez, A. V. [Hospital Reina Sofia. Cordoba (Spain)

2001-07-01

Juvenile mammary papillomatosis is a benign proliferative disease of young patients, generally under 30 years of age. The most frequent clinical presentation is the existence of an elastic and mobile lymph node of the breast. Anatomopathologically, it is characterized because it presents ductal epithelial hyperplasia, sometimes with marked atypia, and there are numerous cysts having different sizes among the findings. It has been associated with an increase in the incidence of breast cancer, both in the patient herself as well as her family. We review the literature on the subject and present the mammographic and ultrasonographic findings of a 22 year old woman diagnosed of juvenile mammary papillomatosis. (Author) 12 refs.

Survival benefits select for group living in a social spider despite reproductive costs

DEFF Research Database (Denmark)

Bilde, T.; Coates, K.S.; Birkhofer, K.

2007-01-01

The evolution of cooperation requires benefits of group living to exceed costs. Hence, some components of fitness are expected to increase with increasing group size, whereas others may decrease because of competition among group members. The social spiders provide an excellent system to investig......The evolution of cooperation requires benefits of group living to exceed costs. Hence, some components of fitness are expected to increase with increasing group size, whereas others may decrease because of competition among group members. The social spiders provide an excellent system...... to investigate the costs and benefits of group living: they occur in groups of various sizes and individuals are relatively short-lived, therefore life history traits and Lifetime Reproductive Success (LRS) can be estimated as a function of group size. Sociality in spiders has originated repeatedly...... and survival in the social spider Stegodyphus dumicola in two populations in Namibia. In both populations, the major benefit of group living was improved survival of colonies and late-instar juveniles with increasing colony size. By contrast, female fecundity, female body size and early juvenile survival...

Comparative pathogenicity of Vibrio spp., Photobacterium damselae ssp. damselae and five isolates of Aeromonas salmonicida ssp. achromogenes in juvenile Atlantic halibut (Hippoglossus hippoglossus).

Science.gov (United States)

Bowden, T J; Bricknell, I R; Preziosi, B M

2018-01-01

Juvenile Atlantic halibut (~100 mg, Hippoglossus hippoglossus) were exposed to Vibrio proteolyticus, a Vibrio spp. isolate, Photobacterium damselae ssp. damselae and five different isolates of Aeromonas salmonicida ssp. achromogenes via an hour-long bath immersion to ascertain their variation in pathogenicity to this fish species. Results were analysed using Kaplan-Meier survival analysis. Analysis of the data from challenges using A. salmonicida ssp. achromogenes revealed three survival values of zero and a spread of values from 0 to 28.43. Challenges using a Vibrio spp isolate, V. proteolyticus and P. damselae resulted in Kaplan-Meier survival estimates of 31.21, 50.41 and 57.21, respectively. As all bacterial species tested could induce juvenile halibut mortalities, they must all be considered as potential pathogens. However, the degree of pathogenicity of A. salmonicida is isolate dependent. © 2017 John Wiley & Sons Ltd.

Changes in habitat availability for outmigrating juvenile salmon (Oncorhychus spp.) following estuary restoration

Science.gov (United States)

Ellings, Christopher S.; Davis, Melanie; Grossman, Eric E.; Hodgson, Sayre; Turner, Kelley L.; Woo PR, Isa; Nakai, Glynnis; Takekawa, Jean E.; Takekawa, John Y.

2016-01-01

The restoration of the Nisqually River Delta (Washington, U.S.A.) represents one of the largest efforts toward reestablishing the ecosystem function and resilience of modified habitat in the Puget Sound, particularly for anadromous salmonid species. The opportunity for outmigrating salmon to access and benefit from the expansion of available tidal habitat can be quantified by several physical attributes, which are related to the ecological and physiological responses of juvenile salmon. We monitored a variety of physical parameters to measure changes in opportunity potential from historic, pre-restoration, and post-restoration habitat conditions at several sites across the delta. These parameters included channel morphology, water quality, tidal elevation, and landscape connectivity. We conducted fish catch surveys across the delta to determine if salmon was utilizing restored estuary habitat. Overall major channel area increased 42% and major channel length increased 131% from pre- to post-restoration conditions. Furthermore, the results of our tidal inundation model indicated that major channels were accessible up to 75% of the time, as opposed to 30% pre-restoration. Outmigrating salmon utilized this newly accessible habitat as quickly as 1 year post-restoration. The presence of salmon in restored tidal channels confirmed rapid post-restoration increases in opportunity potential on the delta despite habitat quality differences between restored and reference sites.

Juvenile giant fibroadenoma

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Vipul Yagnik

2011-07-01

Full Text Available Fibroadenomas are benign solid tumor associated with aberration of normal lobular development. Juvenile giant fibroadenoma is usually single and >5 cm in size /or >500 gms in weight. Important differential diagnoses are: phyllodes tumor and juvenile gigantomastia. Simple excision is the treatment of choice.

Juvenile exposure to predator cues induces a larger egg size in fish

Science.gov (United States)

Segers, Francisca H. I. D.; Taborsky, Barbara

2012-01-01

When females anticipate a hazardous environment for their offspring, they can increase offspring survival by producing larger young. Early environmental experience determines egg size in different animal taxa. We predicted that a higher perceived predation risk by juveniles would cause an increase in the sizes of eggs that they produce as adults. To test this, we exposed juveniles of the mouthbrooding cichlid Eretmodus cyanostictus in a split-brood experiment either to cues of a natural predator or to a control situation. After maturation, females that had been confronted with predators produced heavier eggs, whereas clutch size itself was not affected by the treatment. This effect cannot be explained by a differential female body size because the predator treatment did not influence growth trajectories. The observed increase of egg mass is likely to be adaptive, as heavier eggs gave rise to larger young and in fish, juvenile predation risk drops sharply with increasing body size. This study provides the first evidence that predator cues perceived by females early in life positively affect egg mass, suggesting that these cues allow her to predict the predation risk for her offspring. PMID:21976689

Effects of individual pre-fledging traits and environmental conditions on return patterns in juvenile king penguins.

Science.gov (United States)

Saraux, Claire; Viblanc, Vincent A; Hanuise, Nicolas; Le Maho, Yvon; Le Bohec, Céline

2011-01-01

Despite the importance of early life stages in individuals' life history and population dynamics, very few studies have focused on the constraints to which these juvenile traits are subjected. Based on 10 years of automatic monitoring of over 2500 individuals, we present the first study on the effects of environmental conditions and individual pre-fledging traits on the post-fledging return of non-banded king penguins to their natal colony. Juvenile king penguins returned exclusively within one of the three austral summers following their departure. A key finding is that return rates (range 68-87%) were much higher than previously assumed for this species, importantly meaning that juvenile survival is very close to that of adults. Such high figures suggest little juvenile dispersal, and selection occurring mostly prior to fledging in king penguins. Pre-fledging conditions had a strong quadratic impact on juvenile return rates. As expected, cohorts reared under very unfavourable years (as inferred by the breeding success of the colony) exhibited low return rates but surprisingly, so did those fledged under very favourable conditions. Juvenile sojourns away from the colony were shorter under warm conditions and subsequent return rates higher, suggesting a positive effect of climate warming. The longer the post-fledging trip (1, 2 or 3 years), the earlier in the summer birds returned to their natal colony and the longer they stayed before leaving for the winter journey. The presence of juveniles in the colony was more than twice the duration required for moulting purposes, yet none attempted breeding in the year of their first return. Juvenile presence in the colony may be important for acquiring knowledge on the social and physical colonial environment and may play an important part in the learning process of mating behaviour. Further studies are required to investigate its potential implications on other life-history traits such as recruitment age.

Kelp and Eelgrass in Puget Sound

National Research Council Canada - National Science Library

Mumford, Jr, Thomas F

2007-01-01

.... Shellfish, such as crabs and bivalves, use eelgrass beds for habitat and nursery areas. Fishes such as juvenile salmonids use eelgrass beds as migratory corridors as they pass through Puget Sound; the beds provide both protection from predators and abundant food.

Development of an Effective Transport Media for Juvenile Spring Chinook Salmon to Mitigate Stress and Improve Smolt Survival During Columbia River Fish Hauling Operations, 1985 Final Report.

Energy Technology Data Exchange (ETDEWEB)

Wedemeyer, Gary A.

1985-02-01

Selected transport media consisting of mineral salt additions (Na/sup +/, Cl/sup -/, Ca/sup + +/, PO/sub 4//sup -3/, HCO/sub 3//sup -/, and Mg/sup + +/), mineral salts plus tranquilizing concentrations of tricaine methane sulfonate (MS-222), or MS-222 alone were tested for their ability to mitigate stress and increase smolt survival during single and mixed species hauling of Columbia River spring chinook salmon (Oncorhynchus tshawytscha) and steelhead trout (Salmo gairdneri). Successful stress mitigation was afforded by several formulations as indicated by protection against life-threatening osmoregulatory and other physiological dysfunctions, and against immediate and delayed hauling mortality. Effects on the seawater survival and growth of smolts hauled in transport media were used as the overall criterion of success. Of the fourteen chemical formulations tested, 10 ppM MS-222 emerged as top-rated in terms of ability to mitigate physiological stress during single and mixed species transport of juvenile spring chinook salmon at hauling densities of 0.5 or 1.0 lb/gallon. Immediate and delayed mortalities from hauling stress were also reduced, but benefits to early marine growth and survival were limited to about the first month in seawater. The two physical factors tested (reduced light intensity and water temperature) were generally less effective than mineral salt additions in mitigating hauling stress, but the degree of protection afforded by reduced light intensity was nevertheless judged to be physiologically beneficial. 36 refs., 1 fig., 19 tabs.

Juvenile Idiopathic Arthritis

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Kenan Barut

2017-04-01

Full Text Available Juvenile idiopathic arthritis is the most common chronic rheumatic disease of unknown aetiology in childhood and predominantly presents with peripheral arthritis. The disease is divided into several subgroups, according to demographic characteristics, clinical features, treatment modalities and disease prognosis. Systemic juvenile idiopathic arthritis, which is one of the most frequent disease subtypes, is characterized by recurrent fever and rash. Oligoarticular juvenile idiopathic arthritis, common among young female patients, is usually accompanied by anti-nuclear antibodie positivity and anterior uveitis. Seropositive polyarticular juvenile idiopathic arthritis, an analogue of adult rheumatoid arthritis, is seen in less than 10% of paediatric patients. Seronegative polyarticular juvenile idiopathic arthritis, an entity more specific for childhood, appears with widespread large- and small-joint involvement. Enthesitis-related arthritis is a separate disease subtype, characterized by enthesitis and asymmetric lower-extremity arthritis. This disease subtype represents the childhood form of adult spondyloarthropathies, with human leukocyte antigen-B27 positivity and uveitis but commonly without axial skeleton involvement. Juvenile psoriatic arthritis is characterized by a psoriatic rash, accompanied by arthritis, nail pitting and dactylitis. Disease complications can vary from growth retardation and osteoporosis secondary to treatment and disease activity, to life-threatening macrophage activation syndrome with multi-organ insufficiency. With the advent of new therapeutics over the past 15 years, there has been a marked improvement in juvenile idiopathic arthritis treatment and long-term outcome, without any sequelae. The treatment of juvenile idiopathic arthritis patients involves teamwork, including an experienced paediatric rheumatologist, an ophthalmologist, an orthopaedist, a paediatric psychiatrist and a physiotherapist. The primary goals

Design and Analysis of Salmonid Tagging Studies in the Columbia Basin, Volume XXI; A Summary of Methods for Conducting Salmonid Fry Mark-Recapture Studies for Estimating Survival in Tributaries, Technical Report 2005-2006.

Energy Technology Data Exchange (ETDEWEB)

Skalski, John

2007-02-01

Productivity and early fry survival can have a major influence on the dynamics of fish stocks. To investigate the early life history of fish, numerous methods have been developed or adapted to these much smaller fish. Some of the marking techniques provide individual identification; many others, only class identification. Some of the tagging techniques require destructive sampling to identify a mark; other methods permit benign examination and rerelease of captured fish. Sixteen alternative release-recapture designs for conducting fry survival investigations were examined. Eleven approaches were found capable of estimating survival parameters; five were not. Of those methods capable of estimating fry survival, five required unique marks, four required batch-specific marks, and two approaches required remarking and rereleasing captured fry. No approach based on a simple batch mark was capable of statistically estimating survival.

Assessing the relative importance of local and regional processes on the survival of a threatened salmon population.

Science.gov (United States)

Miller, Jessica A; Teel, David J; Peterson, William T; Baptista, Antonio M

2014-01-01

Research on regulatory mechanisms in biological populations often focuses on environmental covariates. An integrated approach that combines environmental indices with organismal-level information can provide additional insight on regulatory mechanisms. Survival of spring/summer Snake River Chinook salmon (Oncorhynchus tshawytscha) is consistently low whereas some adjacent populations with similar life histories experience greater survival. It is not known if populations with differential survival respond similarly during early marine residence, a critical period in the life history. Ocean collections, genetic stock identification, and otolith analyses were combined to evaluate the growth-mortality and match-mismatch hypotheses during early marine residence of spring/summer Snake River Chinook salmon. Interannual variation in juvenile attributes, including size at marine entry and marine growth rate, was compared with estimates of survival and physical and biological metrics. Multiple linear regression and multi-model inference were used to evaluate the relative importance of biological and physical metrics in explaining interannual variation in survival. There was relatively weak support for the match-mismatch hypothesis and stronger evidence for the growth-mortality hypothesis. Marine growth and size at capture were strongly, positively related to survival, a finding similar to spring Chinook salmon from the Mid-Upper Columbia River. In hindcast models, basin-scale indices (Pacific Decadal Oscillation (PDO) and the North Pacific Gyre Oscillation (NPGO)) and biological indices (juvenile salmon catch-per-unit-effort (CPUE) and a copepod community index (CCI)) accounted for substantial and similar portions of variation in survival for juvenile emigration years 1998-2008 (R2>0.70). However, in forecast models for emigration years 2009-2011, there was an increasing discrepancy between predictions based on the PDO (50-448% of observed value) compared with those based on

Assessing the relative importance of local and regional processes on the survival of a threatened salmon population.

Directory of Open Access Journals (Sweden)

Jessica A Miller

Full Text Available Research on regulatory mechanisms in biological populations often focuses on environmental covariates. An integrated approach that combines environmental indices with organismal-level information can provide additional insight on regulatory mechanisms. Survival of spring/summer Snake River Chinook salmon (Oncorhynchus tshawytscha is consistently low whereas some adjacent populations with similar life histories experience greater survival. It is not known if populations with differential survival respond similarly during early marine residence, a critical period in the life history. Ocean collections, genetic stock identification, and otolith analyses were combined to evaluate the growth-mortality and match-mismatch hypotheses during early marine residence of spring/summer Snake River Chinook salmon. Interannual variation in juvenile attributes, including size at marine entry and marine growth rate, was compared with estimates of survival and physical and biological metrics. Multiple linear regression and multi-model inference were used to evaluate the relative importance of biological and physical metrics in explaining interannual variation in survival. There was relatively weak support for the match-mismatch hypothesis and stronger evidence for the growth-mortality hypothesis. Marine growth and size at capture were strongly, positively related to survival, a finding similar to spring Chinook salmon from the Mid-Upper Columbia River. In hindcast models, basin-scale indices (Pacific Decadal Oscillation (PDO and the North Pacific Gyre Oscillation (NPGO and biological indices (juvenile salmon catch-per-unit-effort (CPUE and a copepod community index (CCI accounted for substantial and similar portions of variation in survival for juvenile emigration years 1998-2008 (R2>0.70. However, in forecast models for emigration years 2009-2011, there was an increasing discrepancy between predictions based on the PDO (50-448% of observed value compared with

Ocean acidification reduces the crystallographic control in juvenile mussel shells.

Science.gov (United States)

Fitzer, Susan C; Cusack, Maggie; Phoenix, Vernon R; Kamenos, Nicholas A

2014-10-01

Global climate change threatens the oceans as anthropogenic carbon dioxide causes ocean acidification and reduced carbonate saturation. Future projections indicate under saturation of aragonite, and potentially calcite, in the oceans by 2100. Calcifying organisms are those most at risk from such ocean acidification, as carbonate is vital in the biomineralisation of their calcium carbonate protective shells. This study highlights the importance of multi-generational studies to investigate how marine organisms can potentially adapt to future projected global climate change. Mytilus edulis is an economically important marine calcifier vulnerable to decreasing carbonate saturation as their shells comprise two calcium carbonate polymorphs: aragonite and calcite. M. edulis specimens were cultured under current and projected pCO2 (380, 550, 750 and 1000μatm), following 6months of experimental culture, adults produced second generation juvenile mussels. Juvenile mussel shells were examined for structural and crystallographic orientation of aragonite and calcite. At 1000μatm pCO2, juvenile mussels spawned and grown under this high pCO2 do not produce aragonite which is more vulnerable to carbonate under-saturation than calcite. Calcite and aragonite were produced at 380, 550 and 750μatm pCO2. Electron back scatter diffraction analyses reveal less constraint in crystallographic orientation with increased pCO2. Shell formation is maintained, although the nacre crystals appear corroded and crystals are not so closely layered together. The differences in ultrastructure and crystallography in shells formed by juveniles spawned from adults in high pCO2 conditions may prove instrumental in their ability to survive ocean acidification. Copyright © 2014 Elsevier Inc. All rights reserved.

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.

Assessment of Salmonids and their Habitat Conditions in the Walla Walla River Basin of Washington : 2000 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Mendel, Glen Wesley; Karl, David; Coyle, Terrence

2001-11-01

Concerns about the decline of native salmon and trout populations have increased among natural resource managers and the public in recent years. As a result, a multitude of initiatives have been implemented at the local, state, and federal government levels. These initiatives include management plans and actions intended to protect and restore salmonid fishes and their habitats. In 1998 bull trout were listed under the Endangered Species Act (ESA), as ''Threatened'', for the Walla Walla River and its tributaries. Steelhead were listed as ''Threatened'' in 1999 for the mid-Columbia River and its tributaries. These ESA listings emphasize the need for information about the threatened salmonid populations and their habitats. The Washington Department of Fish and Wildlife (WDFW) is entrusted with ''the preservation, protection, and perpetuation of fish and wildlife....[and to] maximize public recreational or commercial opportunities without impairing the supply of fish and wildlife (WAC 77. 12.010).'' In consideration of this mandate, the WDFW submitted a proposal in December 1997 to the Bonneville Power Administration (BPA) for a study to assess salmonid distribution, relative abundance, genetics, and the condition of their habitats in the Walla Walla River basin. The primary purposes of this project are to collect baseline biological and habitat data, to identify major data gaps, and to draw conclusions whenever possible. The study reported herein details the findings of the 2000 field season (March to November, 2000).

Development of a System-Wide Predator Control Program: Stepwise Implementation of a Predation Index, Predator Control Fisheries, and Evaluation Plan in the Columbia River Basin; Northern Pikeminnow Management Program, 2002 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Porter, Russell G.; Winther, Eric C.; Fox, Lyle G.

2004-01-01

This report presents results for year twelve in a basin-wide program to harvest northern pikeminnow1 (Ptychocheilus oregonensis). This program was started in an effort to reduce predation by northern pikeminnow on juvenile salmonids during their emigration from natal streams to the ocean. Earlier work in the Columbia River Basin suggested predation by northern pikeminnow on juvenile salmonids might account for most of the 10-20% mortality juvenile salmonids experience in each of eight Columbia River and Snake River reservoirs. Modeling simulations based on work in John Day Reservoir from 1982 through 1988 indicated that, if predator-size northern pikeminnow were exploited at a 10-20% rate, the resulting restructuring of their population could reduce their predation on juvenile salmonids by 50%. To test this hypothesis, we implemented a sport-reward angling fishery and a commercial longline fishery in the John Day Pool in 1990. We also conducted an angling fishery in areas inaccessible to the public at four dams on the mainstem Columbia River and at Ice Harbor Dam on the Snake River. Based on the success of these limited efforts, we implemented three test fisheries on a system-wide scale in 1991--a tribal longline fishery above Bonneville Dam, a sport-reward fishery, and a dam-angling fishery. Low catch of target fish and high cost of implementation resulted in discontinuation of the tribal longline fishery. However, the sport-reward and dam-angling fisheries were continued in 1992 and 1993. In 1992, we investigated the feasibility of implementing a commercial longline fishery in the Columbia River below Bonneville Dam and found that implementation of this fishery was also infeasible. Estimates of combined annual exploitation rates resulting from the sport-reward and damangling fisheries remained at the low end of our target range of 10-20%. This suggested the need for additional effective harvest techniques. During 1991 and 1992, we developed and tested a modified

Ontogeny of salinity tolerance and evidence for seawater-entry preparation in juvenile green sturgeon, Acipenser medirostris.

Science.gov (United States)

Allen, Peter J; McEnroe, Maryann; Forostyan, Tetyana; Cole, Stephanie; Nicholl, Mary M; Hodge, Brian; Cech, Joseph J

2011-12-01

We measured the ontogeny of salinity tolerance and the preparatory hypo-osmoregulatory physiological changes for seawater entry in green sturgeon (Acipenser medirostris), an anadromous species occurring along the Pacific Coast of North America. Salinity tolerance was measured every 2 weeks starting in 40-day post-hatch (dph) juveniles and was repeated until 100% survival at 34‰ was achieved. Fish were subjected to step increases in salinity (5‰ 12 h(-1)) that culminated in a 72-h exposure to a target salinity, and treatment groups (0, 15, 20, 25, 30, 34‰; and abrupt exposure to 34‰) were adjusted as fish developed. After 100% survival was achieved (134 dph), a second experiment tested two sizes of fish for 28-day seawater (33‰) tolerance, and gill and gastrointestinal tract tissues were sampled. Their salinity tolerance increased and plasma osmolality decreased with increasing size and age, and electron microscopy revealed three types of mitochondria-rich cells: one in fresh water and two in seawater. In addition, fish held on a natural photoperiod in fresh water at 19°C showed peaks in cortisol, thyroid hormones and gill and pyloric ceca Na(+), K(+)-ATPase activities at body sizes associated with seawater tolerance. Therefore, salinity tolerance in green sturgeon increases during ontogeny (e.g., as these juveniles may move down estuaries to the ocean) with increases in body size. Also, physiological and morphological changes associated with seawater readiness increased in freshwater-reared juveniles and peaked at their seawater-tolerant ages and body sizes. Their seawater-ready body size also matched that described for swimming performance decreases, presumably associated with downstream movements. Therefore, juvenile green sturgeon develop structures and physiological changes appropriate for seawater entry while growing in fresh water, indicating that hypo-osmoregulatory changes may proceed by multiple routes in sturgeons.

Can biosecurity and local network properties predict pathogen species richness in the salmonid industry?

Science.gov (United States)

More, Simon J.; Geoghegan, Fiona; McManus, Catherine; Hill, Ashley E.; Martínez-López, Beatriz

2018-01-01

Salmonid farming in Ireland is mostly organic, which implies limited disease treatment options. This highlights the importance of biosecurity for preventing the introduction and spread of infectious agents. Similarly, the effect of local network properties on infection spread processes has rarely been evaluated. In this paper, we characterized the biosecurity of salmonid farms in Ireland using a survey, and then developed a score for benchmarking the disease risk of salmonid farms. The usefulness and validity of this score, together with farm indegree (dichotomized as ≤ 1 or > 1), were assessed through generalized Poisson regression models, in which the modeled outcome was pathogen richness, defined here as the number of different diseases affecting a farm during a year. Seawater salmon (SW salmon) farms had the highest biosecurity scores with a median (interquartile range) of 82.3 (5.4), followed by freshwater salmon (FW salmon) with 75.2 (8.2), and freshwater trout (FW trout) farms with 74.8 (4.5). For FW salmon and trout farms, the top ranked model (in terms of leave-one-out information criteria, looic) was the null model (looic = 46.1). For SW salmon farms, the best ranking model was the full model with both predictors and their interaction (looic = 33.3). Farms with a higher biosecurity score were associated with lower pathogen richness, and farms with indegree > 1 (i.e. more than one fish supplier) were associated with increased pathogen richness. The effect of the interaction between these variables was also important, showing an antagonistic effect. This would indicate that biosecurity effectiveness is achieved through a broader perspective on the subject, which includes a minimization in the number of suppliers and hence in the possibilities for infection to enter a farm. The work presented here could be used to elaborate indicators of a farm’s disease risk based on its biosecurity score and indegree, to inform risk-based disease surveillance and

Can biosecurity and local network properties predict pathogen species richness in the salmonid industry?

Directory of Open Access Journals (Sweden)

Tadaishi Yatabe

Full Text Available Salmonid farming in Ireland is mostly organic, which implies limited disease treatment options. This highlights the importance of biosecurity for preventing the introduction and spread of infectious agents. Similarly, the effect of local network properties on infection spread processes has rarely been evaluated. In this paper, we characterized the biosecurity of salmonid farms in Ireland using a survey, and then developed a score for benchmarking the disease risk of salmonid farms. The usefulness and validity of this score, together with farm indegree (dichotomized as ≤ 1 or > 1, were assessed through generalized Poisson regression models, in which the modeled outcome was pathogen richness, defined here as the number of different diseases affecting a farm during a year. Seawater salmon (SW salmon farms had the highest biosecurity scores with a median (interquartile range of 82.3 (5.4, followed by freshwater salmon (FW salmon with 75.2 (8.2, and freshwater trout (FW trout farms with 74.8 (4.5. For FW salmon and trout farms, the top ranked model (in terms of leave-one-out information criteria, looic was the null model (looic = 46.1. For SW salmon farms, the best ranking model was the full model with both predictors and their interaction (looic = 33.3. Farms with a higher biosecurity score were associated with lower pathogen richness, and farms with indegree > 1 (i.e. more than one fish supplier were associated with increased pathogen richness. The effect of the interaction between these variables was also important, showing an antagonistic effect. This would indicate that biosecurity effectiveness is achieved through a broader perspective on the subject, which includes a minimization in the number of suppliers and hence in the possibilities for infection to enter a farm. The work presented here could be used to elaborate indicators of a farm's disease risk based on its biosecurity score and indegree, to inform risk-based disease surveillance and

The Design and Analysis of Salmonid Tagging Studies in the Columbia Basin; Volume XII; A Multinomial Model for Estimating Ocean Survival from Salmonid Coded Wire-Tag Data.

Energy Technology Data Exchange (ETDEWEB)

Ryding, Kristen E.; Skalski, John R.

1999-06-01

The purpose of this report is to illustrate the development of a stochastic model using coded wire-tag (CWT) release and age-at-return data, in order to regress first year ocean survival probabilities against coastal ocean conditions and climate covariates.

Virucidal activity of two Iodophors to salmonid viruses

Science.gov (United States)

Amend, Donald F.; Pietsch, John P.

1972-01-01

Wescodyne® and Betadine®, organic iodine complexes, were compared in vitro for virucidal activity against infectious hematopoietic necrosis (IHN), infectious pancreatic necrosis (IPN), and viral hemorrhagic septicemia (VHS) viruses. Both iodophors were about equally effective on all three viruses. Each iodophor completely destroyed IHN virus within 30 sec at 12 ppm iodine, and was not affected by water hardness. Virucidal activity, however, was reduced at pH levels above 8.0 and in the presence of organic matter. Wescodyne was also compared with seven disinfectants commonly used in fish hatcheries, for virucidal properties against IHN virus. Wescodyne and chlorine were the only disinfectants to completely destroy the virus. Either Wescodyne or Betadine would effectively destroy the salmonid viruses at less than 25 ppm iodine within 5 min in solutions near neutrality.

Monitoring of downstream salmon and steelhead at federal hydroelectric facilities -- 1995. Annual report 1995

International Nuclear Information System (INIS)

Martinson, R.D.; Graves, R.J.; Langeslay, M.J.; Killins, S.D.

1996-12-01

The seaward migration of juvenile salmonids was monitored by the National Marine Fisheries Service (NMFS) at Bonneville and John Day Dams on the Columbia river in 1995. The NMFS Smolt Monitoring Project is part of a larger Smolt Monitoring Program (SMP) coordinated by the Fish Passage Center (FPC) for the Columbia Basin Fish and Wildlife Authority. This program focuses on protecting, mitigating, and enhancing fish populations affected by the development and operation of hydroelectric power plants on the Columbia River. The purpose of the SMP is to monitor the migration of the juvenile salmonid stocks in the Columbia basin and make flow and spill recommendations designed to facilitate fish passage. Data are also used for travel time, migration timing, and relative run size analysis. The purpose of the NMFS portion of the program is to provide FPC with species and project specific real time data from John Day and Bonneville Dams

Juvenile angiofibromer

DEFF Research Database (Denmark)

Thuesen, Anne Daugaard; Jakobsen, John; Nepper-Rasmussen, Jørgen

2005-01-01

Juvenile angiofibroma is a rare, benign, rich vascular tumor, and approximately one new case is diagnosed in Denmark each year. It sits in the foramen sphenopalatinum and occurs in boys from 14 to 25 years of age. The most frequent initial symptoms are nasal obstruction and epistaxis. Through...... the years, the treatment of juvenile angiofibroma has included many methods, including surgical excision, electrocoagulation, interstitial or external radiation therapy, cryosurgery, hormone administration and chemotherapy. Radiation, chemotherapy and surgery have proven to be the most effective treatments...

Impact of beaver dams on abundance and distribution of anadromous salmonids in two lowland streams in Lithuania.

Science.gov (United States)

Virbickas, Tomas; Stakėnas, Saulius; Steponėnas, Andrius

2015-01-01

European beaver dams impeded movements of anadromous salmonids as it was established by fishing survey, fish tagging and redd counts in two lowland streams in Lithuania. Significant differences in abundancies of other litophilic fish species and evenness of representation by species in the community were detected upstream and downstream of the beaver dams. Sea trout parr marked with RFID tags passed through several successive beaver dams in upstream direction, but no tagged fish were detected above the uppermost dam. Increase in abundances of salmonid parr in the stream between the beaver dams and decrease below the dams were recorded in November, at the time of spawning of Atlantic salmon and sea trout, but no significant changes were detected in the sections upstream of the dams. After construction of several additional beaver dams in the downstream sections of the studied streams, abundance of Atlantic salmon parr downstream of the dams decreased considerably in comparison with that estimated before construction.

Impact of beaver dams on abundance and distribution of anadromous salmonids in two lowland streams in Lithuania.

Directory of Open Access Journals (Sweden)

Tomas Virbickas

Full Text Available European beaver dams impeded movements of anadromous salmonids as it was established by fishing survey, fish tagging and redd counts in two lowland streams in Lithuania. Significant differences in abundancies of other litophilic fish species and evenness of representation by species in the community were detected upstream and downstream of the beaver dams. Sea trout parr marked with RFID tags passed through several successive beaver dams in upstream direction, but no tagged fish were detected above the uppermost dam. Increase in abundances of salmonid parr in the stream between the beaver dams and decrease below the dams were recorded in November, at the time of spawning of Atlantic salmon and sea trout, but no significant changes were detected in the sections upstream of the dams. After construction of several additional beaver dams in the downstream sections of the studied streams, abundance of Atlantic salmon parr downstream of the dams decreased considerably in comparison with that estimated before construction.

Parenting and juvenile delinquency

NARCIS (Netherlands)

Hoeve, M.

2008-01-01

Juvenile delinquency is a noteworthy problem. This thesis addressed the association between parenting and juvenile delinquency by analyzing the concepts of parenting adopted in family research in relation to criminological concepts and measures of delinquent behavior. Four studies were conducted.

Sociality, selection, and survival: Simulated evolution of mortality with intergenerational transfers and food sharing

OpenAIRE

Lee, Ronald

2008-01-01

Why do humans survive so long past reproductive age, and why does juvenile mortality decline after birth, both contrary to the classic theory of aging? Previous work has shown formally that intergenerational transfers can explain both these patterns. Here, simulations confirm those results under weaker assumptions and explore how different social arrangements shape life-history evolution. Simulated single-sex hunter–gatherers survive, forage, reproduce, and share food with kin and nonkin in w...

A model for simulating the active dispersal of juvenile sea turtles with a case study on western Pacific leatherback turtles

Science.gov (United States)

Lalire, Maxime

2017-01-01

Oceanic currents are known to broadly shape the dispersal of juvenile sea turtles during their pelagic stage. Accordingly, simple passive drift models are widely used to investigate the distribution at sea of various juvenile sea turtle populations. However, evidence is growing that juveniles do not drift purely passively but also display some swimming activity likely directed towards favorable habitats. We therefore present here a novel Sea Turtle Active Movement Model (STAMM) in which juvenile sea turtles actively disperse under the combined effects of oceanic currents and habitat-driven movements. This model applies to all sea turtle species but is calibrated here for leatherback turtles (Dermochelys coriacea). It is first tested in a simulation of the active dispersal of juveniles originating from Jamursba-Medi, a main nesting beach of the western Pacific leatherback population. Dispersal into the North Pacific Ocean is specifically investigated. Simulation results demonstrate that, while oceanic currents broadly shape the dispersal area, modeled habitat-driven movements strongly structure the spatial and temporal distribution of juveniles within this area. In particular, these movements lead juveniles to gather in the North Pacific Transition Zone (NPTZ) and to undertake seasonal north-south migrations. More surprisingly, juveniles in the NPTZ are simulated to swim mostly towards west which considerably slows down their progression towards the American west coast. This increases their residence time, and hence the risk of interactions with fisheries, in the central and eastern part of the North Pacific basin. Simulated habitat-driven movements also strongly reduce the risk of cold-induced mortality. This risk appears to be larger among the juveniles that rapidly circulate into the Kuroshio than among those that first drift into the North Equatorial Counter Current (NECC). This mechanism might induce marked interannual variability in juvenile survival as the

A model for simulating the active dispersal of juvenile sea turtles with a case study on western Pacific leatherback turtles.

Science.gov (United States)

Gaspar, Philippe; Lalire, Maxime

2017-01-01

Oceanic currents are known to broadly shape the dispersal of juvenile sea turtles during their pelagic stage. Accordingly, simple passive drift models are widely used to investigate the distribution at sea of various juvenile sea turtle populations. However, evidence is growing that juveniles do not drift purely passively but also display some swimming activity likely directed towards favorable habitats. We therefore present here a novel Sea Turtle Active Movement Model (STAMM) in which juvenile sea turtles actively disperse under the combined effects of oceanic currents and habitat-driven movements. This model applies to all sea turtle species but is calibrated here for leatherback turtles (Dermochelys coriacea). It is first tested in a simulation of the active dispersal of juveniles originating from Jamursba-Medi, a main nesting beach of the western Pacific leatherback population. Dispersal into the North Pacific Ocean is specifically investigated. Simulation results demonstrate that, while oceanic currents broadly shape the dispersal area, modeled habitat-driven movements strongly structure the spatial and temporal distribution of juveniles within this area. In particular, these movements lead juveniles to gather in the North Pacific Transition Zone (NPTZ) and to undertake seasonal north-south migrations. More surprisingly, juveniles in the NPTZ are simulated to swim mostly towards west which considerably slows down their progression towards the American west coast. This increases their residence time, and hence the risk of interactions with fisheries, in the central and eastern part of the North Pacific basin. Simulated habitat-driven movements also strongly reduce the risk of cold-induced mortality. This risk appears to be larger among the juveniles that rapidly circulate into the Kuroshio than among those that first drift into the North Equatorial Counter Current (NECC). This mechanism might induce marked interannual variability in juvenile survival as the

Effect of supplemental taurine on juvenile channel catfish Ictalurus punctatus growth and survival after challenge with Edwardsiella ictaluri

Science.gov (United States)

Juvenile channel catfish, Ictalurus punctatus, were fed a basal diet that contained major protein (soybean meal, cottonseed meal) and energy (ground corn grain) ingredients that were derived from plant sources. Plant-source ingredients are considered to be low (taurine content. In add...

Juvenile delinquency and correctional treatment in Britain

OpenAIRE

堀尾, 良弘; ホリオ, ヨシヒロ; Yoshihiro, Horio

2006-01-01

Japanese modernistic culture is influenced not a little from Britain. In looking at the Juvenile Law and the history of correctional treatment in Britain, understanding of today's juvenile delinquency and treatment deepen. Moreover, the background and issue of juvenile delinquency in Britain are also discussed. As a feature of the juvenile delinquency in Britain, the common field with Japan and the field peculiar to Britain became clear in each. It is common to the world that the juvenile del...

Non-native salmonids affect amphibian occupancy at multiple spatial scales

Science.gov (United States)

Pilliod, David S.; Hossack, Blake R.; Bahls, Peter F.; Bull, Evelyn L.; Corn, Paul Stephen; Hokit, Grant; Maxell, Bryce A.; Munger, James C.; Wyrick, Aimee

2010-01-01

Aim The introduction of non-native species into aquatic environments has been linked with local extinctions and altered distributions of native species. We investigated the effect of non-native salmonids on the occupancy of two native amphibians, the long-toed salamander (Ambystoma macrodactylum) and Columbia spotted frog (Rana luteiventris), across three spatial scales: water bodies, small catchments and large catchments. Location Mountain lakes at ≥ 1500 m elevation were surveyed across the northern Rocky Mountains, USA. Methods We surveyed 2267 water bodies for amphibian occupancy (based on evidence of reproduction) and fish presence between 1986 and 2002 and modelled the probability of amphibian occupancy at each spatial scale in relation to habitat availability and quality and fish presence. Results After accounting for habitat features, we estimated that A. macrodactylum was 2.3 times more likely to breed in fishless water bodies than in water bodies with fish. Ambystoma macrodactylum also was more likely to occupy small catchments where none of the water bodies contained fish than in catchments where at least one water body contained fish. However, the probability of salamander occupancy in small catchments was also influenced by habitat availability (i.e. the number of water bodies within a catchment) and suitability of remaining fishless water bodies. We found no relationship between fish presence and salamander occupancy at the large-catchment scale, probably because of increased habitat availability. In contrast to A. macrodactylum, we found no relationship between fish presence and R. luteiventris occupancy at any scale. Main conclusions Our results suggest that the negative effects of non-native salmonids can extend beyond the boundaries of individual water bodies and increase A. macrodactylum extinction risk at landscape scales. We suspect that niche overlap between non-native fish and A. macrodactylum at higher elevations in the northern Rocky

Cumulative effects of logging road sediment on salmonid populations in the Clearwater River, Jefferson County, Washington

Science.gov (United States)

C. J. Cederholm; L. M. Reid; E. O. Salo

1981-01-01

Abstract - The nature of sediment production from logging roads and the effect of the resulting sediment on salmonid spawning success in the Clearwater River drainage have been studied for eight years. The study includes intensive and extensive analyses of field situations, supplemented by several controlled experiments. It was found that significant amounts (15-25...

Juvenile prison in parallel legislation

Directory of Open Access Journals (Sweden)

Lutovac Mitar

2016-01-01

Full Text Available The need for punishment of juveniles occurred from the time when there was no clear line separating them from the adult criminal population. At the same time, the evolution of the juvenile punishment is not in itself involve substantial changes to their criminal status. On the contrary, the status of minors in society did not show serious differences regarding the status of young adults, as well as the adult elderly. On the other hand, on the ground of their punishment is recorded deviations that go in the direction of application of mild corporal punishment. Closing the minor was performed in a physically separate parts of the general penal institutions with the use of a lower degree of restrictions while serving juvenile prison. Due to the different treatment of minors during the evolution of their criminal status leads to their different treatment in comparative law. That is why we are witnessing the existence of numerous differences in the juvenile punishment in some countries in the world. On the European continent there is a wide range of different legal solutions when it comes to punishing juveniles. There are considerable differences in the procedure pronouncing juvenile prison and in particular penal treatment of juveniles in penitentiary institutions. For these reasons, the author has decided to show the basic statutory provisions in the part that relates to the issue of punishment of minors in the legislation of individual countries.

Minthorn Springs Creek Summer Juvenile Release and Adult Collection Facility; 1994 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Rowan, Gerald D.

1995-05-01

The Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and Oregon Department of Fish and Wildlife (ODFW) are cooperating in a joint effort to enhance steelhead and re-establish salmon runs in the Umatilla River Basin. Bonifer Pond, Minthorn Springs and Imeques C-mem-ini-kem acclimation facilities are operated for acclimation and release of juvenile summer steelhead (Oncorhynchus mykiss), fall and spring chinook salmon (O. tshawytscha) and coho salmon (O, kisutch). Minthorn is also used for holding and spawning summer steelhead, fall chinook and coho salmon. In the spring of 1994, juvenile summer steelhead were acclimated at Bonifer and Minthorn. At Imeques C-mem-ini-kem, juvenile spring chinook were acclimated in the spring and fall. A total of 92 unmarked and 42 marked summer steelhead were collected for broodstock at Three Mile Dam from October 1, 1993 through May 2, 1994 and held at Minthorn. An estimated 234,432 green eggs were taken from 48 females. The eggs were transferred to Irrigon Hatchery for incubation and early rearing. Fingerlings were transferred to Umatilla Hatchery for final rearing and release into the Umatilla River in 1995. Fall chinook and coho salmon broodstock were not collected in 1994. Coded-wire tag recovery information was accessed to determine the contribution of Umatilla River releases to ocean, Columbia River and Umatilla River fisheries. Total estimated juvenile adult survival rates are detailed in this document.

Predicting occurrence of juvenile shark habitat to improve conservation planning.

Science.gov (United States)

Oh, Beverly Z L; Sequeira, Ana M M; Meekan, Mark G; Ruppert, Jonathan L W; Meeuwig, Jessica J

2017-06-01

Fishing and habitat degradation have increased the extinction risk of sharks, and conservation strategies recognize that survival of juveniles is critical for the effective management of shark populations. Despite the rapid expansion of marine protected areas (MPAs) globally, the paucity of shark-monitoring data on large scales (100s-1000s km) means that the effectiveness of MPAs in halting shark declines remains unclear. Using data collected by baited remote underwater video systems (BRUVS) in northwestern Australia, we developed generalized linear models to elucidate the ecological drivers of habitat suitability for juvenile sharks. We assessed occurrence patterns at the order and species levels. We included all juvenile sharks sampled and the 3 most abundant species sampled separately (grey reef [Carcharhinus amblyrhynchos], sandbar [Carcharhinus plumbeus], and whitetip reef sharks [Triaenodon obesus]). We predicted the occurrence of juvenile sharks across 490,515 km 2 of coastal waters and quantified the representation of highly suitable habitats within MPAs. Our species-level models had higher accuracy (ĸ ≥ 0.69) and deviance explained (≥48%) than our order-level model (ĸ = 0.36 and deviance explained of 10%). Maps of predicted occurrence revealed different species-specific patterns of highly suitable habitat. These differences likely reflect different physiological or resource requirements between individual species and validate concerns over the utility of conservation targets based on aggregate species groups as opposed to a species-focused approach. Highly suitable habitats were poorly represented in MPAs with the most restrictions on extractive activities. This spatial mismatch possibly indicates a lack of explicit conservation targets and information on species distribution during the planning process. Non-extractive BRUVS provided a useful platform for building the suitability models across large scales to assist conservation planning across

Survival and swimming behavior of insecticide-exposed larvae and pupae of the yellow fever mosquito Aedes aegypti

Science.gov (United States)

2014-01-01

Background The yellow fever mosquito Aedes aegypti is essentially a container-inhabiting species that is closely associated with urban areas. This species is a vector of human pathogens, including dengue and yellow fever viruses, and its control is of paramount importance for disease prevention. Insecticide use against mosquito juvenile stages (i.e. larvae and pupae) is growing in importance, particularly due to the ever-growing problems of resistance to adult-targeted insecticides and human safety concerns regarding such use in human dwellings. However, insecticide effects on insects in general and mosquitoes in particular primarily focus on their lethal effects. Thus, sublethal effects of such compounds in mosquito juveniles may have important effects on their environmental prevalence. In this study, we assessed the survival and swimming behavior of A. aegypti 4th instar larvae (L4) and pupae exposed to increasing concentrations of insecticides. We also assessed cell death in the neuromuscular system of juveniles. Methods Third instar larvae of A. aegypti were exposed to different concentrations of azadirachtin, deltamethrin, imidacloprid and spinosad. Insect survival was assessed for 10 days. The distance swam, the resting time and the time spent in slow swimming were assessed in 4th instar larvae (L4) and pupae. Muscular and nervous cells of L4 and pupae exposed to insecticides were marked with the TUNEL reaction. The results from the survival bioassays were subjected to survival analysis while the swimming behavioral data were subjected to analyses of covariance, complemented with a regression analysis. Results All insecticides exhibited concentration-dependent effects on survival of larvae and pupae of the yellow fever mosquito. The pyrethroid deltamethrin was the most toxic insecticide followed by spinosad, imidacloprid, and azadirachtin, which exhibited low potency against the juveniles. All insecticides except azadirachtin reduced L4 swimming speed and

Survival and swimming behavior of insecticide-exposed larvae and pupae of the yellow fever mosquito Aedes aegypti.

Science.gov (United States)

Tomé, Hudson Vv; Pascini, Tales V; Dângelo, Rômulo Ac; Guedes, Raul Nc; Martins, Gustavo F

2014-04-24

The yellow fever mosquito Aedes aegypti is essentially a container-inhabiting species that is closely associated with urban areas. This species is a vector of human pathogens, including dengue and yellow fever viruses, and its control is of paramount importance for disease prevention. Insecticide use against mosquito juvenile stages (i.e. larvae and pupae) is growing in importance, particularly due to the ever-growing problems of resistance to adult-targeted insecticides and human safety concerns regarding such use in human dwellings. However, insecticide effects on insects in general and mosquitoes in particular primarily focus on their lethal effects. Thus, sublethal effects of such compounds in mosquito juveniles may have important effects on their environmental prevalence. In this study, we assessed the survival and swimming behavior of A. aegypti 4th instar larvae (L4) and pupae exposed to increasing concentrations of insecticides. We also assessed cell death in the neuromuscular system of juveniles. Third instar larvae of A. aegypti were exposed to different concentrations of azadirachtin, deltamethrin, imidacloprid and spinosad. Insect survival was assessed for 10 days. The distance swam, the resting time and the time spent in slow swimming were assessed in 4th instar larvae (L4) and pupae. Muscular and nervous cells of L4 and pupae exposed to insecticides were marked with the TUNEL reaction. The results from the survival bioassays were subjected to survival analysis while the swimming behavioral data were subjected to analyses of covariance, complemented with a regression analysis. All insecticides exhibited concentration-dependent effects on survival of larvae and pupae of the yellow fever mosquito. The pyrethroid deltamethrin was the most toxic insecticide followed by spinosad, imidacloprid, and azadirachtin, which exhibited low potency against the juveniles. All insecticides except azadirachtin reduced L4 swimming speed and wriggling movements. A

Survival of fishes after impingement on traveling screens at Hudson River power plants

International Nuclear Information System (INIS)

Muessig, P.H.; Hutchison, J.B.; King, L.R.; Ligotino, R.J.; Daley, M.

1988-01-01

The survival of Hudson River fishes, juveniles and adults, after they had been impinged on continuously rotated traveling screens at the Bowline Point and Danskammer Point power plants was examined. Survival of principal species was similar at the two plants, and estimates of survival improved as monitoring stress was reduced. Adjusted for survival of control fish, survival over 84-108 h after fish were recovered from the screens was highest for Atlantic tomcod, striped bass, and white perch (50-90%) and lowest for bay anchovy, alewife, and blueback herring; other species showed intermediate survival. Survival of striped bass and white perch was positively correlated with water temperature in winter and with conductivity in spring and fall. Continual rotation of the screens, which shortens the average time that fish are impinged, increased survival over that associated with intermittent rotation. 24 refs., 9 figs., 4 tabs

Effect of cadmium, chromium, lead and metal mixtures on survival and growth of juveniles of the scallop Argopecten ventricosus (Sowerby II, 1842).

Science.gov (United States)

Sobrino-Figueroa, Alma S; Cáceres-Martínez, Carlos; Botello, Alfonso V; Nunez-Nogueira, G

2007-08-01

The effects of Cd, Cr, Pb and their mixtures on the growth and sensitivity of the scallop Argopecten ventricosus were analyzed in this study. Cadmium showed to be more toxic metal to juveniles (96 hour median lethal concentration (LC(50)) = 0.396 mg Cd/L), followed by lead (LC(50) = 0.830 mg Pb/L) and chromium (LC(50) = 3.430 mg Cr/L). Cadmium toxicity was 8 times higher than chromium and 2 times than lead. The most toxic combination was Cd + Cr + Pb. (LC(50) = 0.302 mg/L). Based on toxic units analyses (T.U.), a synergistic effect was observed for Cr + Pb and Cd + Cr + Pb. (T.U. = 0.374; T.U. = 0.403), and antagonic effects for Cd + Cr and Cd + Pb (T.U. = 1.26; T.U. = 1.43) respectively. The level of effect (from high to low) on the growth of A. ventricosus juveniles was: Cd > Cd + Cr + Pb > Cr > Pb. The EC(50) (metal concentration where a reduction of 50% growing rate is observed) obtained were: Cd = 0.018 mg/L, Cd + Cr + Pb = 0.104 mg/L, Cr = 0.51 mg/L and Pb = 4.21 mg/L. These results suggest that A. ventricosus juveniles are more sensitive to these metals in comparison to other juveniles from other bivalve species (e.g., A. irradians, Mytillus edulis, Crassostrea virginica).

Assessment of salmonids and their habitat conditions in the Walla Walla River Basin of Washington : 2000 annual report; ANNUAL

International Nuclear Information System (INIS)

Mendel, Glen Wesley; Karl, David; Coyle, Terrence

2001-01-01

Concerns about the decline of native salmon and trout populations have increased among natural resource managers and the public in recent years. As a result, a multitude of initiatives have been implemented at the local, state, and federal government levels. These initiatives include management plans and actions intended to protect and restore salmonid fishes and their habitats. In 1998 bull trout were listed under the Endangered Species Act (ESA), as ''Threatened'', for the Walla Walla River and its tributaries. Steelhead were listed as ''Threatened'' in 1999 for the mid-Columbia River and its tributaries. These ESA listings emphasize the need for information about the threatened salmonid populations and their habitats. The Washington Department of Fish and Wildlife (WDFW) is entrusted with ''the preservation, protection, and perpetuation of fish and wildlife....[and to] maximize public recreational or commercial opportunities without impairing the supply of fish and wildlife (WAC 77.12.010).'' In consideration of this mandate, the WDFW submitted a proposal in December 1997 to the Bonneville Power Administration (BPA) for a study to assess salmonid distribution, relative abundance, genetics, and the condition of their habitats in the Walla Walla River basin. The primary purposes of this project are to collect baseline biological and habitat data, to identify major data gaps, and to draw conclusions whenever possible. The study reported herein details the findings of the 2000 field season (March to November, 2000)

Bilateral, independent juvenile nasopharyngeal angiofibroma

DEFF Research Database (Denmark)

Mørkenborg, Marie-Louise; Frendø, M; Stavngaard, T

2015-01-01

BACKGROUND: Juvenile nasopharyngeal angiofibroma is a benign, vascular tumour that primarily occurs in adolescent males. Despite its benign nature, aggressive growth patterns can cause potential life-threatening complications. Juvenile nasopharyngeal angiofibroma is normally unilateral, originating...... from the sphenopalatine artery, but bilateral symptoms can occur if a large tumour extends to the contralateral side of the nasopharynx. This paper presents the first reported case of true bilateral extensive juvenile nasopharyngeal angiofibroma involving clinically challenging pre-surgical planning...... embolisation. Radical removal performed as one-step, computer-assisted functional endoscopic sinus surgery was performed. The follow-up period was uncomplicated. CONCLUSION: This case illustrates the importance of suspecting bilateral juvenile nasopharyngeal angiofibroma in patients presenting with bilateral...

Criminal Profiles of Violent Juvenile Sex and Violent Juvenile Non-Sex Offenders: An Explorative Longitudinal Study

Science.gov (United States)

van Wijk, Anton Ph.; Mali, Bas R. F.; Bullens, Ruud A. R.; Vermeiren, Robert R.

2007-01-01

Few studies have longitudinally investigated the criminal profiles of violent juvenile sex and violent juvenile non-sex offenders. To make up for this lack, this study used police records of juveniles to determine the nature of the criminal profiles of violent sex offenders (n = 226) and violent non-sex offenders (n = 4,130). All offenders…

Fall and winter survival of brook trout and brown trout in a north-central Pennsylvania watershed

Science.gov (United States)

Sweka, John A.; Davis, Lori A.; Wagner, Tyler

2017-01-01

Stream-dwelling salmonids that spawn in the fall generally experience their lowest survival during the fall and winter due to behavioral changes associated with spawning and energetic deficiencies during this time of year. We used data from Brook Trout Salvelinus fontinalis and Brown Trout Salmo trutta implanted with radio transmitters in tributaries of the Hunts Run watershed of north-central Pennsylvania to estimate survival from the fall into the winter seasons (September 2012–February 2013). We examined the effects that individual-level covariates (trout species, size, and movement rates) and stream-level covariates (individual stream and cumulative drainage area of a stream) have on survival. Brook Trout experienced significantly lower survival than Brown Trout, especially in the early fall during their peak spawning period. Besides a significant species effect, none of the other covariates examined influenced survival for either species. A difference in life history between these species, with Brook Trout having a shorter life expectancy than Brown Trout, is likely the primary reason for the lower survival of Brook Trout. However, Brook Trout also spawn earlier in the fall than Brown Trout and low flows during Brook Trout spawning may have resulted in a greater risk of predation for Brook Trout compared with Brown Trout, thereby also contributing to the observed differences in survival between these species. Our estimates of survival can aid parameterization of future population models for Brook Trout and Brown Trout through the spawning season and into winter.

Juvenile morphology in baleen whale phylogeny.

Science.gov (United States)

Tsai, Cheng-Hsiu; Fordyce, R Ewan

2014-09-01

Phylogenetic reconstructions are sensitive to the influence of ontogeny on morphology. Here, we use foetal/neonatal specimens of known species of living baleen whales (Cetacea: Mysticeti) to show how juvenile morphology of extant species affects phylogenetic placement of the species. In one clade (sei whale, Balaenopteridae), the juvenile is distant from the usual phylogenetic position of adults, but in the other clade (pygmy right whale, Cetotheriidae), the juvenile is close to the adult. Different heterochronic processes at work in the studied species have different influences on juvenile morphology and on phylogenetic placement. This study helps to understand the relationship between evolutionary processes and phylogenetic patterns in baleen whale evolution and, more in general, between phylogeny and ontogeny; likewise, this study provides a proxy how to interpret the phylogeny when fossils that are immature individuals are included. Juvenile individuals in the peramorphic acceleration clades would produce misleading phylogenies, whereas juvenile individuals in the paedomorphic neoteny clades should still provide reliable phylogenetic signals.

Synthesis of juvenile lamprey migration and passage research and monitoring at Columbia and Snake River Dams

Science.gov (United States)