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Sample records for atlantic cod populations

  1. Bay-scale population structure in coastal Atlantic cod in Labrador and Newfoundland, Canada

    DEFF Research Database (Denmark)

    Ruzzante, D.E.; Wroblewski, J.S.; Taggart, C.T.

    2000-01-01

    Polymorphisms at five microsatellite DNA loci provide evidence that Atlantic cod Gadus morhua inhabiting Gilbert Bay, Labrador are genetically distinguishable from offshore cod on the north- east Newfoundland shelf and from inshore cod in Trinity Bay, Newfoundland. Antifreeze activity in the blood...... of population structure suggest that important barriers to gene flow exist among five components that include two inshore (Gilbert and Trinity Bay) and three offshore cod aggregations on the north-east Newfoundland Shelf and the Grand Bank. D-A and D-SW estimates of genetic distance that involve Gilbert Bay cod...

  2. Hierarchical modelling of temperature and habitat size effects on population dynamics of North Atlantic cod

    DEFF Research Database (Denmark)

    Mantzouni, Irene; Sørensen, Helle; O'Hara, Robert B.

    2010-01-01

    and Beverton and Holt stock–recruitment (SR) models were extended by applying hierarchical methods, mixed-effects models, and Bayesian inference to incorporate the influence of these ecosystem factors on model parameters representing cod maximum reproductive rate and carrying capacity. We identified......Understanding how temperature affects cod (Gadus morhua) ecology is important for forecasting how populations will develop as climate changes in future. The effects of spawning-season temperature and habitat size on cod recruitment dynamics have been investigated across the North Atlantic. Ricker...

  3. Bay-scale population structure in coastal Atlantic cod in Labrador and Newfoundland, Canada

    DEFF Research Database (Denmark)

    Ruzzante, D.E.; Wroblewski, J.S.; Taggart, C.T.

    2000-01-01

    Polymorphisms at five microsatellite DNA loci provide evidence that Atlantic cod Gadus morhua inhabiting Gilbert Bay, Labrador are genetically distinguishable from offshore cod on the north- east Newfoundland shelf and from inshore cod in Trinity Bay, Newfoundland. Antifreeze activity in the bloo...

  4. Ocean Acidification Effects on Atlantic Cod Larval Survival and Recruitment to the Fished Population.

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    Stiasny, Martina H; Mittermayer, Felix H; Sswat, Michael; Voss, Rüdiger; Jutfelt, Fredrik; Chierici, Melissa; Puvanendran, Velmurugu; Mortensen, Atle; Reusch, Thorsten B H; Clemmesen, Catriona

    2016-01-01

    How fisheries will be impacted by climate change is far from understood. While some fish populations may be able to escape global warming via range shifts, they cannot escape ocean acidification (OA), an inevitable consequence of the dissolution of anthropogenic carbon dioxide (CO2) emissions in marine waters. How ocean acidification affects population dynamics of commercially important fish species is critical for adapting management practices of exploited fish populations. Ocean acidification has been shown to impair fish larvae's sensory abilities, affect the morphology of otoliths, cause tissue damage and cause behavioural changes. Here, we obtain first experimental mortality estimates for Atlantic cod larvae under OA and incorporate these effects into recruitment models. End-of-century levels of ocean acidification (~1100 μatm according to the IPCC RCP 8.5) resulted in a doubling of daily mortality rates compared to present-day CO2 concentrations during the first 25 days post hatching (dph), a critical phase for population recruitment. These results were consistent under different feeding regimes, stocking densities and in two cod populations (Western Baltic and Barents Sea stock). When mortality data were included into Ricker-type stock-recruitment models, recruitment was reduced to an average of 8 and 24% of current recruitment for the two populations, respectively. Our results highlight the importance of including vulnerable early life stages when addressing effects of climate change on fish stocks.

  5. Inferring genetic connectivity in real populations, exemplified by coastal and oceanic Atlantic cod.

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    Spies, Ingrid; Hauser, Lorenz; Jorde, Per Erik; Knutsen, Halvor; Punt, André E; Rogers, Lauren A; Stenseth, Nils Chr

    2018-04-19

    Genetic data are commonly used to estimate connectivity between putative populations, but translating them to demographic dispersal rates is complicated. Theoretical equations that infer a migration rate based on the genetic estimator F ST , such as Wright's equation, F ST ≈ 1/(4 N e m + 1), make assumptions that do not apply to most real populations. How complexities inherent to real populations affect migration was exemplified by Atlantic cod in the North Sea and Skagerrak and was examined within an age-structured model that incorporated genetic markers. Migration was determined under various scenarios by varying the number of simulated migrants until the mean simulated level of genetic differentiation matched a fixed level of genetic differentiation equal to empirical estimates. Parameters that decreased the N e / N t ratio (where N e is the effective and N t is the total population size), such as high fishing mortality and high fishing gear selectivity, increased the number of migrants required to achieve empirical levels of genetic differentiation. Higher maturity-at-age and lower selectivity increased N e / N t and decreased migration when genetic differentiation was fixed. Changes in natural mortality, fishing gear selectivity, and maturity-at-age within expected limits had a moderate effect on migration when genetic differentiation was held constant. Changes in population size had the greatest effect on the number of migrants to achieve fixed levels of F ST , particularly when genetic differentiation was low, F ST ≈ 10 -3 Highly variable migration patterns, compared with constant migration, resulted in higher variance in genetic differentiation and higher extreme values. Results are compared with and provide insight into the use of theoretical equations to estimate migration among real populations. Copyright © 2018 the Author(s). Published by PNAS.

  6. Epitope mapping of the major allergen from Atlantic cod in Spanish population reveals different IgE-binding patterns.

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    Perez-Gordo, Marina; Pastor-Vargas, Carlos; Lin, Jing; Bardina, Ludmilla; Cases, Barbara; Ibáñez, Maria Dolores; Vivanco, Fernando; Cuesta-Herranz, Javier; Sampson, Hugh A

    2013-07-01

    IgE-epitope mapping of allergens reveal important information about antigen components involved in allergic reactions. The peptide-based microarray immunoassay has been used to map epitopes of some food allergens. We developed a peptide microarray immunoassay to map allergenic epitopes in parvalbumin from Atlantic cod (Gad m 1), the most consumed cod species in Spain. Sera from 13 fish-allergic patients with specific IgE to cod parvalbumin were used. A library of overlapping peptides was synthesized, representing the primary sequence of Gad m 1. Peptides were used to analyze allergen-specific IgE antibodies in patient sera. 100% of the patients recognized one antigenic region of 15 amino acids in length in Gad m 1. This region only partially correlated with one of the three antigenic determinants of Gad c 1 (Allergen M), parvalbumin from Baltic cod (Gadus callarias). In the 3D model of the protein, this region was located on the surface of the protein. We have identified a relevant antigenic region in Gad m 1. This epitope could be considered as a severity marker and provides additional information to improve fish allergy diagnosis and the design of safe immunotherapeutic tools. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Harvesting Atlantic Cod under Climate Variability

    Science.gov (United States)

    Oremus, K. L.

    2016-12-01

    Previous literature links the growth of a fishery to climate variability. This study uses an age-structured bioeconomic model to compare optimal harvest in the Gulf of Maine Atlantic cod fishery under a variable climate versus a static climate. The optimal harvest path depends on the relationship between fishery growth and the interest rate, with higher interest rates dictating greater harvests now at the cost of long-term stock sustainability. Given the time horizon of a single generation of fishermen under assumptions of a static climate, the model finds that the economically optimal management strategy is to harvest the entire stock in the short term and allow the fishery to collapse. However, if the biological growth of the fishery is assumed to vary with climate conditions, such as the North Atlantic Oscillation, there will always be pulses of high growth in the stock. During some of these high-growth years, the growth of the stock and its economic yield can exceed the growth rate of the economy even under high interest rates. This implies that it is not economically optimal to exhaust the New England cod fishery if NAO is included in the biological growth function. This finding may have theoretical implications for the management of other renewable yet exhaustible resources whose growth rates are subject to climate variability.

  8. Large effective population size and temporal genetic stability in Atlantic cod (Gadus morhua) in the southern Gulf of St. Lawrence

    DEFF Research Database (Denmark)

    Therkildsen, Nina Overgaard; Eg Nielsen, Einar; Swain, Douglas P.

    2010-01-01

    Worldwide, many commercial fish stocks have experienced dramatic declines due to overfishing. Such fisheries-induced population reductions could potentially erode the genetic diversity of marine fish populations. Based on analyses of DNA extracted from archived and contemporary samples, this paper...

  9. What is the carrying capacity for fish in the ocean? A meta analysis of population dynamics of North Atlantic cod

    DEFF Research Database (Denmark)

    Myers, R.A.; MacKenzie, Brian; Bowen, K.G.

    2001-01-01

    used empirical Bayes techniques to estimate the maximum reproductive rate and carrying capacity of each stock. In all cases, the empirical Bayes estimates were biologically reasonable, whereas a stock by stock analysis occasionally yielded nonsensical parameter estimates (e.g., infinite values). Our...... analysis showed that the carrying capacity per unit area varied by more than 20-fold among populations and that much of this variation was related to temperature. That is, the carrying capacity per square kilometre declines as temperature increases....

  10. Structure of chymotrypsin variant B from Atlantic cod, Gadus morhua

    DEFF Research Database (Denmark)

    Leth-Larsen, Rikke; Asgeirsson, B; Thórólfsson, M

    1996-01-01

    The amino-acid sequence of chymotrypsin variant B isolated from the pyloric caeca of Atlantic cod has been elucidated. The characterization of the primary structure is based on N-terminal Edman degradation and mass spectrometry of the native protein and enzymatically derived peptides. Chymotrypsi...... autolysis sites, cod variant B only contains a single autolysis site. The three-dimensional structures of the A- and B-variants of cod has been modelled on the known crystal structure of bovine alpha-chymotrypsin showing almost superimposable structures....

  11. Spatial and Temporal Patterns in the Cod Fisheries of the North Atlantic

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    Anne Hayden

    2015-01-01

    Full Text Available Atlantic Cod Gadus morhua has been subject to commercial exploitation since the thirteenth century. An analysis of cod fisheries over space and time reveals a pattern of serial depletion that reflects the cross-scale interaction of fish population structure, economic incentives, developments in fishing technology, and government efforts to limit access to fishing areas. Three case studies from Newfoundland and Labrador, the larger Northwest Atlantic, and the Gulf of Maine illustrate a pattern of fish population depletion followed by expansion of fishing activity that repeats at a range of scales. The meta-population structure of cod populations allows overharvesting, even when strict but broadscale controls are in place. The results argue for the reform of fisheries management to incorporate governance that more closely reflects the scale of the local components of metapopulations.

  12. Occurrence of anisakid nematodes in Atlantic cod (Gadus morhua) and Greenland cod (Gadus ogac), West Greenland

    DEFF Research Database (Denmark)

    Mouritsen, Kim N.; Hedeholm, Rasmus; Schack, Henriette B.

    2010-01-01

    Anisakid nematodes commonly infect gadids, and are of economic and aesthetic importance to the commercial fishing industry in Greenland as some species are pathogenic to humans. However, very little is known about the occurrence of these parasites and their impact on the hosts in Greenland waters....... During a survey in 2005, stomach sample of 227 Atlantic cod (Gadus morhua) and 64 Greenland cod (Gadus ogac) was collected in Godthaab and Sisimiut fiord systems in West Greenland waters. All cod were dissected for stomach contents and anisakid nematodes were removed from the visceral cavity. Third stage...... nematode species regarding prevalence of infection and mean infection intensity was evident, and there was no relationship between fish condition and the intensity of nematode infections. Standardised for size, capelin-eating cod were in better condition and more heavily infected than fish subsisting...

  13. Genome architecture enables local adaptation of Atlantic cod despite high connectivity

    DEFF Research Database (Denmark)

    Barth, Julia M I; Berg, Paul R; Jonsson, Per R.

    2017-01-01

    Adaptation to local conditions is a fundamental process in evolution; however, mechanisms maintaining local adaptation despite high gene flow are still poorly understood. Marine ecosystems provide a wide array of diverse habitats that frequently promote ecological adaptation even in species...... characterized by strong levels of gene flow. As one example, populations of the marine fish Atlantic cod (Gadus morhua) are highly connected due to immense dispersal capabilities but nevertheless show local adaptation in several key traits. By combining population genomic analyses based on 12K single......-nucleotide polymorphisms with larval dispersal patterns inferred using a biophysical ocean model, we show that Atlantic cod individuals residing in sheltered estuarine habitats of Scandinavian fjords mainly belong to offshore oceanic populations with considerable connectivity between these diverse ecosystems. Nevertheless...

  14. A millennium of north-east Atlantic cod juvenile growth trajectories inferred from archaeological otoliths.

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    Guðbjörg Ásta Ólafsdóttir

    Full Text Available Archaeological excavations of historical fishing sites across the North Atlantic have recovered high quantities of Atlantic cod (Gadus morhua bones. In the current study we use Atlantic cod otoliths from archaeological excavations of a historical fishing sites in north-west Iceland, dated to AD 970 -AD 1910 to examine historical growth trajectories of cod. No large scale growth variations or shifts in growth patterns were observed in the current chronologies, supporting the stability of historical Atlantic cod growth trajectories. The most significant variation in growth patterns was consistent with those that have been observed in recent times, for example, reduced early juvenile growth during periods of colder ocean temperature. The current results represent a high resolution chronological record of north-east Atlantic cod growth, greatly increasing the prior temporal range of such data, thereby providing a valuable baseline for a broad range of studies on Atlantic cod growth.

  15. Exophiala angulospora causes systemic inflammation in atlantic cod Gadus morhua.

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    Gjessing, Mona Cecilie; Davey, Marie; Kvellestad, Agnar; Vrålstad, Trude

    2011-10-06

    Species of Exophiala are opportunistic fungal pathogens that may infect a broad range of warm- and cold-blooded animals, including salmonids and Atlantic cod. In the present study, we observed abnormal swimming behaviour and skin pigmentation and increased mortality in cod kept in an indoor tank. Necropsy revealed foci of different sizes with a greyish to brownish colour in internal organs of diseased fish. The foci consisted of ramifying darkly pigmented fungal hyphae surrounded by distinct layers of inflammatory cells, including macrophage-like cells. In the inner layer with many hyphae, the macrophage-like cells were dead. We observed no apparent restriction of fungal growth by the inflammatory response. A darkly pigmented fungus was repeatedly isolated in pure culture from foci of diseased fish and identified as Exophiala angulospora using morphological and molecular characters. This species has not been previously reported to cause disease in cod, but has been reported as an opportunistic pathogen of both marine and freshwater fish. Based on the morphology and sequence analysis presented here, we conclude that E. angulospora caused the observed chronic multifocal inflammation in internal organs of cod, leading to severe disease and mortality.

  16. Conserving marine biodiversity: insights from life-history trait candidate genes in Atlantic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Hansen, Jakob Hemmer; Therkildsen, Nina Overgaard; Meldrup, Dorte

    2014-01-01

    Recent technological developments have facilitated an increased focus on identifying genomic regions underlying adaptive trait variation in natural populations, and it has been advocated that this information should be important for designating population units for conservation. In marine fishes...... are under selection in natural populations of Atlantic cod. Furthermore, we find that patterns of variation in outlier markers do not align with those observed at selectively neutral markers, and that outlier markers identify conservation units on finer geographical scales than those revealed when analysing...... only neutral markers. Accordingly, results also suggest that information about adaptive genetic variation will be useful for targeted conservation and management in this and other marine species...

  17. Atlantic Cod (Gadus morhua benefits from the availability of seagrass (Zostera marina nursery habitat

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    Richard J. Lilley

    2014-12-01

    Full Text Available The Atlantic cod (Gadus morhua is a species of significant economic and historic importance but infamous for its decline. Apart from overfishing, the causes of this decline and its subsequent lack of recovery remain largely unresolved. Indeed, the degree to which specific habitats are important for this species remains unquantified at the scale of North Atlantic. Here, the literature on the role of eelgrass meadows (Zostera marina as valuable nursery habitat for the Atlantic cod is reviewed and synthesized. Evidence is presented on relative densities of Atlantic cod in shallow water environments and in eelgrass meadows in comparison to alternative habitats. In addition, evidence pertaining to the ’viability gains’ attributed to the use of eelgrass meadows as nursery habitat (growth and survival by juvenile Atlantic cod is analyzed. Although juvenile Atlantic cod use of Z. marina is found to be facultative, when possible, available literatures indicates that they may select Z. marina as a nursery habitat where they are found in high density (average of at least 246 ha−1. From their use of Z. marina habitat the juvenile Atlantic cod receives viability benefits from it, improving their chances of reaching maturation. This paper provides strong evidence that eelgrass meadows are of significant importance to contributing to Atlantic cod stocks. Keywords: Zostera marina, Eelgrass, Gadus morhua, Fisheries, Juveniles, Nursery habitat

  18. The Effects of Temperature, Hypoxia and Hypercapnia on the Metabolism of Atlantic Cod Gadus morhua

    DEFF Research Database (Denmark)

    Tirsgård, Bjørn

    in the water conditions affecting their performance, growth and reproduction. Variations in the water conditions between years and due to climatic changes, affects the survival rate, population dynamic and bio-energetic distribution of the Atlantic cod (Hansson et al., 1996; Essington et al., 2001...... into bio-energetic models used to predict survival, growth and reproduction rates and cod stock dynamics. Furthermore, due to the growing interest of the continuing global increase in atmospheric and oceanic CO2 levels (ICES, 2010), and the rapid expansion of fish farming in land-based recirculated...... important for bio-energetic models (Werner et al., 1996; Leising and Franks, 1999; Werner et al., 2001; Lough et al., 2005). The temperature effect on the metabolism of Atlantic cod larvae however have received little attention (Laurence, 1978; Finn et al., 2002; Peck and Buckley, 2008), likely due...

  19. Time matters: post-surgical recovery of gastric evacuation rate in Atlantic cod

    DEFF Research Database (Denmark)

    Behrens, Jane; Gräns, Albin; Andersen, Niels Gerner

    GER was affected after surgically introducing dummies of a blood-flow biotelemetry system into the abdominal cavity of Atlantic cod. Two days post surgery the cod with implants were, together with a control group, force-fed a standardized meal and the stomach contents recovered 24h later...

  20. Genomic signatures of local directional selection in a high gene flow marine organism, the Atlantic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Eg Nielsen, Einar; Hansen, Jakob Hemmer; Poulsen, Nina Aagaard

    2009-01-01

    -associated single nucleotide polymorphisms (SNPs) for evidence of selection in local populations of Atlantic cod (Gadus morhua L.) across the species distribution. Results: Our global genome scan analysis identified eight outlier gene loci with very high statistical support, likely to be subject to directional...... selection in local demes, or closely linked to loci under selection. Likewise, on a regional south/north transect of central and eastern Atlantic populations, seven loci displayed strongly elevated levels of genetic differentiation. Selection patterns among populations appeared to be relatively widespread...

  1. Thermal niche of Atlantic cod Gadus morhua: limits, tolerance and optima

    DEFF Research Database (Denmark)

    Righton, David A.; Andersen, Ken Haste; Neat, Francis

    2010-01-01

    Recent studies in the marine environment have suggested that the limited phenotypic plasticity of cold-adapted species such as Atlantic cod Gadus morhua L. will cause distributions to shift toward the poles in response to rising sea temperatures. Some cod stocks are predicted to collapse, but thi......Recent studies in the marine environment have suggested that the limited phenotypic plasticity of cold-adapted species such as Atlantic cod Gadus morhua L. will cause distributions to shift toward the poles in response to rising sea temperatures. Some cod stocks are predicted to collapse...... niche of approximately 12°C, but latitudinal differences in water temperature meant that cod in the warmer, southern regions experienced 3 times the degree days (DD; ~4000 DD yr–1) than individuals from northern regions (~1200 DD yr–1). Growth rates increased with temperature, reaching a maximum...

  2. Feasibility of Ocean Acoustic Waveguide Remote Sensing (OAWRS of Atlantic Cod with Seafloor Scattering Limitations

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    Ankita D. Jain

    2013-12-01

    Full Text Available Recently reported declines in the population of Atlantic cod have led to calls for additional survey methods for stock assessments. In combination with conventional line-transect methods that may have ambiguities in sampling fish populations, Ocean Acoustic Waveguide Remote Sensing (OAWRS has been shown to have a potential for providing accurate stock assessments (Makris N.C., et al. Science 2009, 323, 1,734–1,737; 54th Northeast Regional Stock Assessment Workshop (54th SAW US Department of Commerce, Northeast Fisheries Science Center, 2012. The use of OAWRS technology enables instantaneous wide-area sensing of fish aggregations over thousands of square kilometers. The ratio of the intensity of scattered returns from fish versus the seafloor in any resolution cell typically determines the maximum fish detection range of OAWRS, which then is a function of fish population density, scattering amplitude and depth distribution, as well as the level of seafloor scattering. With the knowledge of oceanographic parameters, such as bathymetry, sound speed structure and attenuation, we find that a Rayleigh–Born volume scattering approach can be used to efficiently and accurately estimate seafloor scattering over wide areas. From hundreds of OAWRS measurements of seafloor scattering, we determine the Rayleigh–Born scattering amplitude of the seafloor, which we find has a ƒ2,4 frequency dependence below roughly 2 kHz in typical continental shelf environments along the US northeast coast. We then find that it is possible to robustly detect cod aggregations across frequencies at and near swim bladder resonance for observed spawningconfigurations along the U.S. northeast coast, roughly the two octave range 150–600 Hzfor water depths up to roughly 100 m. This frequency range is also optimal for long-rangeocean acoustic waveguide propagation, because it enables multimodal acoustic waveguidepropagation with minimal acoustic absorption and forward

  3. Multidimensionality of behavioural phenotypes in Atlantic cod, Gadus morhua.

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    Meager, Justin J; Fernö, Anders; Skjæraasen, Jon Egil; Järvi, Torbjörn; Rodewald, Petra; Sverdrup, Gisle; Winberg, Svante; Mayer, Ian

    2012-06-25

    Much of the inter-individual variation observed in animal behaviour is now attributed to the existence of behavioural phenotypes or animal personalities. Such phenotypes may be fundamental to fisheries and aquaculture, yet there have been few detailed studies of this phenomenon in exploited marine animals. We investigated the behavioural and neuroendocrine responses of Atlantic cod (Gadus morhua L.), to situations reflecting critical ecological challenges: predator attacks and territorial challenges. Both hatchery-reared and wild fish were tested and behavioural profiles were compared with baseline conditions. We then used an objective, multivariate approach, rather than assigning individuals along one-dimensional behavioural axes, to examine whether distinct behavioural phenotypes were present. Our results indicate that two distinct behavioural phenotypes were evident in fish from each background. In hatchery-reared fish, phenotypes displayed divergent locomotor activity, sheltering, brain monoamine concentrations and responses to competitive challenges. In wild fish, phenotypes were distinguished primarily by locomotor activity, sheltering and responsiveness to predator stimuli. Hatcheries presumably represent a more stressful social environment, and social behaviour and neuroendocrine responses were important in discerning behavioural phenotypes in hatchery fish, whereas antipredator responses were important in discerning phenotypes in wild fish that have previously encountered predators. In both fish types, behavioural and physiological traits that classified individuals into phenotypes were not the same as those that were correlated across situations. These results highlight the multidimensionality of animal personalities, and that the processes that regulate one suite of behavioural traits may be very different to the processes that regulate other behaviours. Copyright © 2012 Elsevier Inc. All rights reserved.

  4. Development of a SNP resource and a genetic linkage map for Atlantic cod (Gadus morhua

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    Higgins Brent

    2010-03-01

    Full Text Available Abstract Background Atlantic cod (Gadus morhua is a species with increasing economic significance for the aquaculture industry. The genetic improvement of cod will play a critical role in achieving successful large-scale aquaculture. While many microsatellite markers have been developed in cod, the number of single nucleotide polymorphisms (SNPs is currently limited. Here we report the identification of SNPs from sequence data generated by a large-scale expressed sequence tag (EST program, focusing on fish originating from Canadian waters. Results A total of 97976 ESTs were assembled to generate 13448 contigs. We detected 4753 SNPs that met our selection criteria (depth of coverage ≥ 4 reads; minor allele frequency > 25%. 3072 SNPs were selected for testing. The percentage of successful assays was 75%, with 2291 SNPs amplifying correctly. Of these, 607 (26% SNPs were monomorphic for all populations tested. In total, 64 (4% of SNPs are likely to represent duplicated genes or highly similar members of gene families, rather than alternative alleles of the same gene, since they showed a high frequency of heterozygosity. The remaining polymorphic SNPs (1620 were categorised as validated SNPs. The mean minor allele frequency of the validated loci was 0.258 (± 0.141. Of the 1514 contigs from which validated SNPs were selected, 31% have a significant blast hit. For the SNPs predicted to occur in coding regions (141, we determined that 36% (51 are non-synonymous. Many loci (1033 SNPs; 64% are polymorphic in all populations tested. However a small number of SNPs (184 that are polymorphic in the Western Atlantic were monomorphic in fish tested from three European populations. A preliminary linkage map has been constructed with 23 major linkage groups and 924 mapped SNPs. Conclusions These SNPs represent powerful tools to accelerate the genetic improvement of cod aquaculture. They have been used to build a genetic linkage map that can be applied to

  5. North Atlantic ecosystem shifts revealed by cod otolith δ15N and δ13C chronologies

    DEFF Research Database (Denmark)

    Pedersen, Jens Brøgger; Nielsen, Jens Munk; Steingrund, Petur

    . To study the link between environmental changes and ecosystem trophic structure we developed δ15N and δ13C chronologies by analyzing the organic matrix of cod otoliths from the Faroe Shelf cod population (1950-2010) and the Nuuk Fjord cod population (1927-2009). Significant correlations between δ15N & δ13C...... of organic matrix of otolith core material (Nuuk Fjord) and annual growth increments in Ocean Quahog (A. Islandica) shells will be included.......Changes in climate and exploitation have caused large fluctuations in the productivity of many North Atlantic cod populations and the collapse of many cod fisheries. These fluctuations are most likely due to a combined effect of physical processes and changes in ecosystem trophic structure...

  6. The effect of external dummy transmitters on oxygen consumption and performance of swimming Atlantic cod

    DEFF Research Database (Denmark)

    Steinhausen, M.F.; Andersen, Niels Gerner; Steffensen, J.F.

    2006-01-01

    Decreased critical swimming speed and increased oxygen consumption (Mo-2) was found for externally tagged Atlantic cod Gadus morhua swimming at a high speed of 0 center dot 9 body length (total length, L-Gamma) s(-1). No difference was found in the standard metabolic rate, indicating...... that the higher Mo-2 for tagged cod was due to drag force rather than increased costs to keep buoyancy. (c) 2006 The Authors Journal compilation (c) 2006 The Fisheries Society of the British Isles....

  7. The effect of carbon dioxide on growth of juvenile Atlantic cod Gadus morhua L

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    Moran, Damian; Støttrup, Josianne

    2011-01-01

    A trial was undertaken to investigate how exposure to graded hypercapnia affected the growth performance of juvenile (15-80 g) Atlantic cod. Juveniles were grown at 20‰ salinity and 10 °C for 55 days under three hypercapnic regimes: low (2 ± 0.9 mg L−1 CO2, 0.6 mm Hg, 1000 μatm), medium (8 ± 0.5 mg...... experiments using marine fish species. The test concentrations were recalculated from the reported carbonate chemistry conditions, and indicated that the CO2 concentration effect threshold may have been overestimated in two of these studies. Our study suggests that juvenile Atlantic cod are more susceptible...

  8. Historical DNA reveals the demographic history of Atlantic cod (Gadus morhua) in medieval and early modern Iceland.

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    Ólafsdóttir, Guðbjörg Ásta; Westfall, Kristen M; Edvardsson, Ragnar; Pálsson, Snæbjörn

    2014-02-22

    Atlantic cod (Gadus morhua) vertebrae from archaeological sites were used to study the history of the Icelandic Atlantic cod population in the time period of 1500-1990. Specifically, we used coalescence modelling to estimate population size and fluctuations from the sequence diversity at the cytochrome b (cytb) and Pantophysin I (PanI) loci. The models are consistent with an expanding population during the warm medieval period, large historical effective population size (NE), a marked bottleneck event at 1400-1500 and a decrease in NE in early modern times. The model results are corroborated by the reduction of haplotype and nucleotide variation over time and pairwise population distance as a significant portion of nucleotide variation partitioned across the 1550 time mark. The mean age of the historical fished stock is high in medieval times with a truncation in age in early modern times. The population size crash coincides with a period of known cooling in the North Atlantic, and we conclude that the collapse may be related to climate or climate-induced ecosystem change.

  9. Effect of produced water on feeding and metabolism of Atlantic cod (Gadus morhua)

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    Volkoff, H.; Parrish, C. [Memorial Univ. of Newfoundland, St. John' s, NL (Canada); Hamoutene, D.; Mabrouk, G.; Samuelson, S.; Mansour, A.; Lee, K. [Fisheries and Oceans Canada, Dartmouth, NS (Canada). Maritimes Region, Ocean Sciences Division

    2007-07-01

    This paper addressed concerns regarding potentially detrimental cumulative effects of waste products from oil industry activities on marine organisms around production sites. The metabolic capacities, feeding and digestive physiology of fish have been shown to change with environmental parameters, which could impact the growth and health status of fish populations. In this study, the effects of produced water (PW) on feeding and metabolism of Atlantic cod was investigated by exposing fish to 0.100 ppm (x 10,000 PW dilution) or 200 ppm (x 500 dilution) of PW for 76 days. Throughout the experiment, food intake and mean weight were monitored. In addition, serum lipids, metabolites and gene expression of a brain appetite regulating factor were measured at the end of the experiment. No significant differences were observed in weight gain or food intake between the 3 groups of fish. Serum metabolites and neuropeptide Y expression remained unchanged between groups. The study is ongoing to complete comparative measurements of whole blood fatty acid profiles in plasma. The preliminary results indicate that feeding and metabolism in cod is not affected by produced water.

  10. The effects of production water, WAF or CEWAF on the fertilization success of Atlantic cod eggs

    International Nuclear Information System (INIS)

    Burridge, L; Wong, D.; Trippel, E.

    2010-01-01

    Production water (PW), dispersed oil, and oil released from offshore oil and gas platforms can adversely affect fish populations. In this study, eggs from Atlantic cod were fertilized in the presence of PW collected from the Terra Nova and Hibernia offshore platforms in 2008. Cod eggs were also fertilized in the presence of the water accommodated fraction (WAF) and chemically enhanced water accommodated fraction (CEWAF) of Alaskan North Slope oil (ANS). Results of the study showed that exposure to the Terra Nova PW at 12 per cent (V/V) or higher resulted in significantly lower fertilization rates than those observed in controls. Exposure to Hibernia PW at 0.5 per cent (V/V) also resulted in significantly lower fertilization rates. The WAF of ANS up to 25 per cent (V/V) had no effect on fertilization rates. At 50 per cent (V/V), the fertilization rate for WAF ANS was much lower than rates observed in controls. The CEWAF significantly reduced fertilization at all tested concentrations.

  11. Genomic Sequencing of Ranaviruses Isolated from Turbot (Scophthalmus maximus) and Atlantic Cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Ariel, Ellen; Steckler, Natalie K.; Subramaniam, Kuttichantran

    2016-01-01

    Ranaviruses have been isolated from Atlantic cod (Gadus morhua) and turbot (Scophthalmus maximus) in Denmark. Phylogenomic analyses revealed that these two ranaviruses are nearly identical and form a distinct clade at the base of the ranavirus tree branching off near other fish ranaviruses....

  12. Male size composition affects male reproductive variance in Atlantic cod Gadus morhua L. spawning aggregations

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    Bekkevold, Dorte

    2006-01-01

    Estimates of Atlantic cod Gadus morhua reproductive success, determined using experimental spawning groups and genetic paternity assignment of offspring, showed that within-group variance in male size correlated positively with the degree of male mating skew, predicting a decrease in male reprodu...

  13. Differential expression of immune and stress genes in the skin of Atlantic cod (Gadus morhua)

    NARCIS (Netherlands)

    Caipang, C.M.A.; Lazado, C.C.; Brinchmann, M.; Rombout, J.H.W.M.; Kiron, V.

    2011-01-01

    The present study describes the transcriptional profiles of selected immune and stress genes with putative important roles in the cutaneous immune defense of Atlantic cod (Gadus morhua). In addition it shows differential expression of many genes at the dorsal and ventral sides of fish, in general

  14. Distribution and drift of Atlantic cod ( Gadus morhua ) eggs and larvae in Greenland offshore waters

    DEFF Research Database (Denmark)

    Wieland, Kai; Hovgård, Holger

    2002-01-01

    Catches of Atlantic cod (Gadus morhua) eggs and larvae from 45 national and international ichthyoplankton surveys conducted in Greenland offshore waters during the period 1950 to 1984 have been compiled and re-analysed. Southeast and Southwest Greenland were identified as im- portant spawning areas...

  15. Daily rhythmicity of clock gene transcripts in atlantic cod fast skeletal muscle.

    Directory of Open Access Journals (Sweden)

    Carlo C Lazado

    Full Text Available The classical notion of a centralized clock that governs circadian rhythmicity has been challenged with the discovery of peripheral oscillators that enable organisms to cope with daily changes in their environment. The present study aimed to identify the molecular clock components in Atlantic cod (Gadus morhua and to investigate their daily gene expression in fast skeletal muscle. Atlantic cod clock genes were closely related to their orthologs in teleosts and tetrapods. Synteny was conserved to varying degrees in the majority of the 18 clock genes examined. In particular, aryl hydrocarbon receptor nuclear translocator-like 2 (arntl2, RAR-related orphan receptor A (rora and timeless (tim displayed high degrees of conservation. Expression profiling during the early ontogenesis revealed that some transcripts were maternally transferred, namely arntl2, cryptochrome 1b and 2 (cry1b and cry2, and period 2a and 2b (per2a and per2b. Most clock genes were ubiquitously expressed in various tissues, suggesting the possible existence of multiple peripheral clock systems in Atlantic cod. In particular, they were all detected in fast skeletal muscle, with the exception of neuronal PAS (Per-Arnt-Single-minded domain-containing protein (npas1 and rora. Rhythmicity analysis revealed 8 clock genes with daily rhythmic expression, namely arntl2, circadian locomotor output cycles kaput (clock, npas2, cry2, cry3 per2a, nuclear receptor subfamily 1, group D, member 1 (nr1d1, and nr1d2a. Transcript levels of the myogenic genes myogenic factor 5 (myf5 and muscleblind-like 1 (mbnl1 strongly correlated with clock gene expression. This is the first study to unravel the molecular components of peripheral clocks in Atlantic cod. Taken together, our data suggest that the putative clock system in fast skeletal muscle of Atlantic cod has regulatory implications on muscle physiology, particularly in the expression of genes related to myogenesis.

  16. Characterization of Atlantic cod spawning habitat and behavior in Icelandic coastal waters.

    Directory of Open Access Journals (Sweden)

    Timothy B Grabowski

    Full Text Available The physical habitat used during spawning may potentially be an important factor affecting reproductive output of broadcast spawning marine fishes, particularly for species with complex, substrate-oriented mating systems and behaviors, such as Atlantic cod Gadus morhua. We characterized the habitat use and behavior of spawning Atlantic cod at two locations off the coast of southwestern Iceland during a 2-d research cruise (15-16 April 2009. We simultaneously operated two different active hydroacoustic gear types, a split beam echosounder and a dual frequency imaging sonar (DIDSON, as well as a remotely operated underwater vehicle (ROV. A total of five fish species were identified through ROV surveys: including cusk Brosme brosme, Atlantic cod, haddock Melanogrammus aeglefinus, lemon sole Microstomus kitt, and Atlantic redfish Sebastes spp. Of the three habitats identified in the acoustic surveys, the transitional habitat between boulder/lava field and sand habitats was characterized by greater fish density and acoustic target strength compared to that of sand or boulder/lava field habitats independently. Atlantic cod were observed behaving in a manner consistent with published descriptions of spawning. Individuals were observed ascending 1-5 m into the water column from the bottom at an average vertical swimming speed of 0.20-0.25 m s(-1 and maintained an average spacing of 1.0-1.4 m between individuals. Our results suggest that cod do not choose spawning locations indiscriminately despite the fact that it is a broadcast spawning fish with planktonic eggs that are released well above the seafloor.

  17. Characterization of Atlantic cod spawning habitat and behavior in Icelandic coastal waters

    Science.gov (United States)

    Grabowski, Timothy B.; Boswell, Kevin M.; McAdam, Bruce J.; Wells, R. J. David; Marteinsdóttir, Gudrún

    2012-01-01

    The physical habitat used during spawning may potentially be an important factor affecting reproductive output of broadcast spawning marine fishes, particularly for species with complex, substrate-oriented mating systems and behaviors, such as Atlantic cod Gadus morhua. We characterized the habitat use and behavior of spawning Atlantic cod at two locations off the coast of southwestern Iceland during a 2-d research cruise (15–16 April 2009). We simultaneously operated two different active hydroacoustic gear types, a split beam echosounder and a dual frequency imaging sonar (DIDSON), as well as a remotely operated underwater vehicle (ROV). A total of five fish species were identified through ROV surveys: including cusk Brosme brosme, Atlantic cod, haddock Melanogrammus aeglefinus, lemon sole Microstomus kitt, and Atlantic redfish Sebastes spp. Of the three habitats identified in the acoustic surveys, the transitional habitat between boulder/lava field and sand habitats was characterized by greater fish density and acoustic target strength compared to that of sand or boulder/lava field habitats independently. Atlantic cod were observed behaving in a manner consistent with published descriptions of spawning. Individuals were observed ascending 1–5 m into the water column from the bottom at an average vertical swimming speed of 0.20–0.25 m s−1 and maintained an average spacing of 1.0–1.4 m between individuals. Our results suggest that cod do not choose spawning locations indiscriminately despite the fact that it is a broadcast spawning fish with planktonic eggs that are released well above the seafloor.

  18. Preferred temperature of juvenile Atlantic cod Gadus morhua with different haemoglobin genotypes at normoxia and moderate hypoxia

    DEFF Research Database (Denmark)

    Petersen, M.F.; Steffensen, J.F.

    2003-01-01

    .2+/-1.5 degrees C while HbI-1 cod preferred 15.4+/-1.1 degrees C, and this preference was significant. The effect of hypoxia (35% oxygen saturation) on the preferred temperature was also measured. Previous studies showed that the preferred temperature of fish decreases during hypoxia, and this was the case for Hb......I-1 cod, which preferred 9.8+/-1.8 degrees C during hypoxia, whereas HbI-2 cod did not show this effect. The results indicate that environmental temperature changes will lead to a distributional change in the different haemoglobin types of Atlantic cod, global warming providing an advantage for HbI-1...... cod. However, since HbI-1 cod prefer a low temperature under hypoxic conditions, a combination of increased water temperature and hypoxia could be unfavourable for Atlantic cod stocks....

  19. Underwater sound from vessel traffic reduces the effective communication range in Atlantic cod and haddock.

    Science.gov (United States)

    Stanley, Jenni A; Van Parijs, Sofie M; Hatch, Leila T

    2017-11-07

    Stellwagen Bank National Marine Sanctuary is located in Massachusetts Bay off the densely populated northeast coast of the United States; subsequently, the marine inhabitants of the area are exposed to elevated levels of anthropogenic underwater sound, particularly due to commercial shipping. The current study investigated the alteration of estimated effective communication spaces at three spawning locations for populations of the commercially and ecologically important fishes, Atlantic cod (Gadus morhua) and haddock (Melanogrammus aeglefinus). Both the ambient sound pressure levels and the estimated effective vocalization radii, estimated through spherical spreading models, fluctuated dramatically during the three-month recording periods. Increases in sound pressure level appeared to be largely driven by large vessel activity, and accordingly exhibited a significant positive correlation with the number of Automatic Identification System tracked vessels at the two of the three sites. The near constant high levels of low frequency sound and consequential reduction in the communication space observed at these recording sites during times of high vocalization activity raises significant concerns that communication between conspecifics may be compromised during critical biological periods. This study takes the first steps in evaluating these animals' communication spaces and alteration of these spaces due to anthropogenic underwater sound.

  20. Allometric relationships to liver tissue concentrations of cyclic volatile methyl siloxanes in Atlantic cod

    International Nuclear Information System (INIS)

    Warner, Nicholas A.; Nøst, Therese H.; Andrade, Hector; Christensen, Guttorm

    2014-01-01

    Spatial distribution and relationship of allometric measurements (length, weight and age) to liver concentrations of cyclic volatile methyl siloxanes (cVMS) including octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclosiloxane (D6) in Atlantic cod (Gadus morhua) collected near the community of Tromsø in Northern Norway were assessed. These congeners were benchmarked against known persistent polychlorinated biphenyls (PCBs 153 and 180) to assess accumulation behavior of cVMS. D5 was the dominate cVMS detected in all fish livers with lipid normalized concentrations up to 10 times or greater than those observed for PCB 153 and 180. D4 and D6 concentration were negatively correlated with fish length and weight, indicating a greater elimination capacity compared to uptake processes with increasing fish size for these chemicals. These results indicate relationships between allometric measurements and cVMS concentrations may account for concentration variations observed within fish and should be assessed in future studies evaluating cVMS bioaccumulation potential. - Highlights: • cVMS spatial distribution investigated within cod surrounding an Arctic community. • Highest cVMS concentrations detected in biota collected near human settlements. • Cod liver concentrations of D5 were higher compared to PCBs. • D4 and D6 liver concentrations were negatively correlated with fish length/weight. - Liver concentrations of cVMS congeners decreased with increasing fish length and weight in Atlantic cod collected near emission sources of cVMS

  1. A Novel Method for Predicting Anisakid Nematode Infection of Atlantic Cod Using Rough Set Theory.

    Science.gov (United States)

    Wąsikowska, Barbara; Sobecka, Ewa; Bielat, Iwona; Legierko, Monika; Więcaszek, Beata

    2018-03-01

    Atlantic cod ( Gadus morhua L.) is one of the most important fish species in the fisheries industries of many countries; however, these fish are often infected with parasites. The detection of pathogenic larval nematodes is usually performed in fish processing facilities by visual examination using candling or by digesting muscles in artificial digestive juices, but these methods are both time and labor intensive. This article presents an innovative approach to the analysis of cod parasites from both the Atlantic and Baltic Sea areas through the application of rough set theory, one of the methods of artificial intelligence, for the prediction of food safety in a food production chain. The parasitological examinations were performed focusing on nematode larvae pathogenic to humans, e.g., Anisakis simplex, Contracaecum osculatum, and Pseudoterranova decipiens. The analysis allowed identification of protocols with which it is possible to make preliminary estimates of the quantity and quality of parasites found in cod catches before detailed analyses are performed. The results indicate that the method used can be an effective analytical tool for these types of data. To achieve this goal, a database is needed that contains the patterns intensity of parasite infections and the conditions of commercial fish species in different localities in their distributions.

  2. Factors regulating early life history dispersal of Atlantic cod (Gadus morhua) from coastal Newfoundland.

    Science.gov (United States)

    Stanley, Ryan R E; deYoung, Brad; Snelgrove, Paul V R; Gregory, Robert S

    2013-01-01

    To understand coastal dispersal dynamics of Atlantic cod (Gadus morhua), we examined spatiotemporal egg and larval abundance patterns in coastal Newfoundland. In recent decades, Smith Sound, Trinity Bay has supported the largest known overwintering spawning aggregation of Atlantic cod in the region. We estimated spawning and dispersal characteristics for the Smith Sound-Trinity Bay system by fitting ichthyoplankton abundance data to environmentally-driven, simplified box models. Results show protracted spawning, with sharply increased egg production in early July, and limited dispersal from the Sound. The model for the entire spawning season indicates egg export from Smith Sound is 13%•day(-1) with a net mortality of 27%•day(-1). Eggs and larvae are consistently found in western Trinity Bay with little advection from the system. These patterns mirror particle tracking models that suggest residence times of 10-20 days, and circulation models indicating local gyres in Trinity Bay that act in concert with upwelling dynamics to retain eggs and larvae. Our results are among the first quantitative dispersal estimates from Smith Sound, linking this spawning stock to the adjacent coastal waters. These results illustrate the biophysical interplay regulating dispersal and connectivity originating from inshore spawning of coastal northwest Atlantic.

  3. Factors regulating early life history dispersal of Atlantic cod (Gadus morhua from coastal Newfoundland.

    Directory of Open Access Journals (Sweden)

    Ryan R E Stanley

    Full Text Available To understand coastal dispersal dynamics of Atlantic cod (Gadus morhua, we examined spatiotemporal egg and larval abundance patterns in coastal Newfoundland. In recent decades, Smith Sound, Trinity Bay has supported the largest known overwintering spawning aggregation of Atlantic cod in the region. We estimated spawning and dispersal characteristics for the Smith Sound-Trinity Bay system by fitting ichthyoplankton abundance data to environmentally-driven, simplified box models. Results show protracted spawning, with sharply increased egg production in early July, and limited dispersal from the Sound. The model for the entire spawning season indicates egg export from Smith Sound is 13%•day(-1 with a net mortality of 27%•day(-1. Eggs and larvae are consistently found in western Trinity Bay with little advection from the system. These patterns mirror particle tracking models that suggest residence times of 10-20 days, and circulation models indicating local gyres in Trinity Bay that act in concert with upwelling dynamics to retain eggs and larvae. Our results are among the first quantitative dispersal estimates from Smith Sound, linking this spawning stock to the adjacent coastal waters. These results illustrate the biophysical interplay regulating dispersal and connectivity originating from inshore spawning of coastal northwest Atlantic.

  4. Microevolution in time and space: SNP analysis of historical DNA reveals dynamic signatures of selection in Atlantic cod

    DEFF Research Database (Denmark)

    Therkildsen, Nina Overgaard; Hansen, Jakob Hemmer; Als, Thomas Damm

    2013-01-01

    of Atlantic cod (Gadus morhua) studied over an 80-year period. Screening of >1000 gene-associated single-nucleotide polymorphisms (SNPs) identified 77 loci that showed highly elevated levels of differentiation, likely as an effect of directional selection, in either time, space or both. Exploratory analysis......Little is known about how quickly natural populations adapt to changes in their environment and how temporal and spatial variation in selection pressures interact to shape patterns of genetic diversity. We here address these issues with a series of genome scans in four overfished populations...... and spatially varying selection. These findings have important implications for our understanding of local adaptation and evolutionary potential in high gene flow organisms and underscore the need to carefully consider all dimensions of biocomplexity for evolutionarily sustainable management...

  5. Correlations between hemoglobin type and temperature preference of juvenile Atlantic cod Gadus morhua

    DEFF Research Database (Denmark)

    Behrens, Jane W.; Gräns, Albin; Therkildsen, Nina Overgaard

    2012-01-01

    Atlantic cod (Gadus morhua L.) exhibits polymorphic hemoglobin variants with the HbI locus showing a strong North-South geographic cline in frequency distribution of three main types (1/1, 1/2 and 2/2). This may indicate selective advantages of the different HbI types under various temperature re...... inconsistent thermoregulatory behavior. To obtain a more definitive picture of the extent to which thermal niches are realized under natural conditions field observations in areas where the 3 HbI types co-exist should be performed...

  6. Accumulation and elimination of methylmercury in Atlantic cod (Gadus morhua L.) following dietary exposure

    Energy Technology Data Exchange (ETDEWEB)

    Amlund, Heidi [National Institute of Nutrition and Seafood Research (NIFES), P.O. Box 2029 Nordnes, 5817 Bergen (Norway)]. E-mail: heidi.amlund@nifes.no; Lundebye, Anne-Katrine [National Institute of Nutrition and Seafood Research (NIFES), P.O. Box 2029 Nordnes, 5817 Bergen (Norway); Berntssen, Marc H.G. [National Institute of Nutrition and Seafood Research (NIFES), P.O. Box 2029 Nordnes, 5817 Bergen (Norway)

    2007-08-01

    Methylmercury is known to bioaccumulate and biomagnify up the marine food chain. Fish from high levels of the marine food chain may contain relatively high concentrations of mercury, and most (>70%) of the mercury found in muscle is methylmercury. In aquaculture, marine protein (mainly fishmeal) is the dominant source of methylmercury, and this raises some concern with regards to fish welfare and consumer safety. A dietary exposure study, including a depuration period, was carried out in order to study the accumulation and elimination of methylmercury in Atlantic cod (Gadus morhua L.), and to estimate the transfer of methylmercury from feed to fish. Fish were sampled throughout a three month exposure period and a three month depuration period. Muscle samples were fractionated into a protein and a lipid fraction by lipid extraction using methanol and chloroform. Mercury and methylmercury were determined by inductively coupled plasma mass spectrometry (ICPMS) and gas chromatography-inductively coupled plasma mass spectrometry (GC-ICPMS), respectively. A continuous accumulation of methylmercury, after a lag period of 10 days, was observed in muscle tissue during the three months exposure to methylmercury (0.95+/-0.03{mu}g Hg/g feed, n=6). After three months, the final concentration in muscle was 0.38+/-0.04{mu}g Hg/gww (n=6), where methylmercury constituted 90-95% of the mercury present. The elimination of methylmercury from muscle was slow and incomplete (within the three months of depuration) with an estimated elimination half-life (t{sub 1/2}) of 377 days. The transfer of methylmercury from feed to Atlantic cod, described by the estimated absorption efficiency, was 38%. In muscle more than 99% of the mercury was found in the protein fraction. These results suggest that Atlantic cod readily takes up dietary methylmercury, which is efficiently accumulated into muscle, where it is incorporated into larger peptides or proteins. Comparable results were found for

  7. Accumulation and elimination of methylmercury in Atlantic cod (Gadus morhua L.) following dietary exposure

    International Nuclear Information System (INIS)

    Amlund, Heidi; Lundebye, Anne-Katrine; Berntssen, Marc H.G.

    2007-01-01

    Methylmercury is known to bioaccumulate and biomagnify up the marine food chain. Fish from high levels of the marine food chain may contain relatively high concentrations of mercury, and most (>70%) of the mercury found in muscle is methylmercury. In aquaculture, marine protein (mainly fishmeal) is the dominant source of methylmercury, and this raises some concern with regards to fish welfare and consumer safety. A dietary exposure study, including a depuration period, was carried out in order to study the accumulation and elimination of methylmercury in Atlantic cod (Gadus morhua L.), and to estimate the transfer of methylmercury from feed to fish. Fish were sampled throughout a three month exposure period and a three month depuration period. Muscle samples were fractionated into a protein and a lipid fraction by lipid extraction using methanol and chloroform. Mercury and methylmercury were determined by inductively coupled plasma mass spectrometry (ICPMS) and gas chromatography-inductively coupled plasma mass spectrometry (GC-ICPMS), respectively. A continuous accumulation of methylmercury, after a lag period of 10 days, was observed in muscle tissue during the three months exposure to methylmercury (0.95+/-0.03μg Hg/g feed, n=6). After three months, the final concentration in muscle was 0.38+/-0.04μg Hg/gww (n=6), where methylmercury constituted 90-95% of the mercury present. The elimination of methylmercury from muscle was slow and incomplete (within the three months of depuration) with an estimated elimination half-life (t 1/2 ) of 377 days. The transfer of methylmercury from feed to Atlantic cod, described by the estimated absorption efficiency, was 38%. In muscle more than 99% of the mercury was found in the protein fraction. These results suggest that Atlantic cod readily takes up dietary methylmercury, which is efficiently accumulated into muscle, where it is incorporated into larger peptides or proteins. Comparable results were found for Atlantic salmon

  8. Genomic signatures of local directional selection in a high gene flow marine organism; the Atlantic cod (Gadus morhua

    Directory of Open Access Journals (Sweden)

    Mittelholzer Christian

    2009-12-01

    Full Text Available Abstract Background Marine fishes have been shown to display low levels of genetic structuring and associated high levels of gene flow, suggesting shallow evolutionary trajectories and, possibly, limited or lacking adaptive divergence among local populations. We investigated variation in 98 gene-associated single nucleotide polymorphisms (SNPs for evidence of selection in local populations of Atlantic cod (Gadus morhua L. across the species distribution. Results Our global genome scan analysis identified eight outlier gene loci with very high statistical support, likely to be subject to directional selection in local demes, or closely linked to loci under selection. Likewise, on a regional south/north transect of central and eastern Atlantic populations, seven loci displayed strongly elevated levels of genetic differentiation. Selection patterns among populations appeared to be relatively widespread and complex, i.e. outlier loci were generally not only associated with one of a few divergent local populations. Even on a limited geographical scale between the proximate North Sea and Baltic Sea populations four loci displayed evidence of adaptive evolution. Temporal genome scan analysis applied to DNA from archived otoliths from a Faeroese population demonstrated stability of the intra-population variation over 24 years. An exploratory landscape genetic analysis was used to elucidate potential effects of the most likely environmental factors responsible for the signatures of local adaptation. We found that genetic variation at several of the outlier loci was better correlated with temperature and/or salinity conditions at spawning grounds at spawning time than with geographic distance per se. Conclusion These findings illustrate that adaptive population divergence may indeed be prevalent despite seemingly high levels of gene flow, as found in most marine fishes. Thus, results have important implications for our understanding of the interplay of

  9. Linking size and age at sexual maturation to body growth, productivity and recruitment of Atlantic cod stocks spanning the North Atlantic

    DEFF Research Database (Denmark)

    Köster, Fritz; Trippel, E.A.; Tomkiewicz, Jonna

    2013-01-01

    Sexual maturation patterns of 22 North Atlantic stocks of cod (Gadus morhua) were examined and related to geographical distribution area, ambient water temperature, growth and surplus production. Four patterns were identified, i.e. sexual maturation early in life at small size, early in life...... Atlantic stocks. This comparative analysis suggests that maturation patterns relate to growth potential and surplus production whereas annual production of recruits per unit biomass appears unrelated to average size at sexual maturation...

  10. Characterization of Francisella sp., GM2212, the first Francisella isolate from marine fish, Atlantic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Ottem, Karl F; Nylund, Are; Karlsbakk, Egil

    2007-01-01

    A Francisella sp., isolate GM2212(T), previously isolated from diseased farmed Atlantic cod Gadus morhua in Norway is characterized. The complete 16S rDNA, 16S-23S intergenic spacer, 23S rDNA, 23S-5S intergenic spacer, 5S rDNA, FopA, lipoprotein TUL4 (LpnA), malate dehydrogenase and a hypothetica...

  11. Electrical stunning of farmed Atlantic cod Gadus morhua L.: a comparison of an industrial and experimental method

    NARCIS (Netherlands)

    Digre, H.; Erikson, U.; Misimi, E.; Lambooij, E.; Vis, van de J.W.

    2010-01-01

    An industrial and experimental electrical method for stunning farmed Atlantic cod in air and seawater (SW), respectively, were compared. The impacts of sedation with AQUI-S™ and exercise to exhaustion before electrical stunning were also assessed to monitor the possible depletion of rested muscle

  12. Effects of reproduction on growth and survival in Atlantic cod, Gadus morhua, assessed by comparison to triploids

    DEFF Research Database (Denmark)

    Trippel, Edward A.; Butts, Ian; Babin, Amanda

    2014-01-01

    in captive iteroparous, batch-spawning Atlantic cod (Gadus morhua), utilizing diploids and triploids, knowing that triploid females invest little to no energy into gametogenesis. Based on annual specific growth rate, there was no evidence for a somatic cost of reproduction at ages 2 (virgin year) and 4...

  13. Effect of moderate hypoxia at three acclimation temperatures on stress responses in Atlantic cod with different haemoglobin types

    DEFF Research Database (Denmark)

    Methling, Caroline; Aluru, Neelakanteswar; Vijayan, Mathilakath M

    2010-01-01

    in a difference in stress response to hypoxia exposure. Two hsp70-isoforms (labelled a and b) were detected and they differed in expression in the gills but not in the liver of Atlantic cod. Acclimation temperature significantly affected the expression of hsp70 in the liver, and in an isoform-specific manner...... in the gills. Hypoxia exposure increased the expression of hsp70 in the liver, but not the gills, of cod and this response was not influenced by the acclimation temperature. The expression of hsp70 in both tissues did not differ between fish with different haemoglobin types. Acclimation temperature...... hypoxic exposure influence the organismal and cellular stress responses in Atlantic cod. We hypothesise that HbI-2 fish are more tolerant to short-term hypoxic episodes than HbI-1 fish, and this adaptation may be independent of tissue hsp70 expression....

  14. Plasma FITC-dextran exchange between the primary and secondary circulatory systems in the Atlantic cod, Gadus Morhua

    DEFF Research Database (Denmark)

    Fischer, Claes; Steffensen, John Fleng

    2008-01-01

    Fluorescein isothiocyanate dextran (FITC-dextran) exchange between the primary (PCS) and secondary (SCS) circulatory systems in the Atlantic cod, Gadus morhua (Linnaeus, 1752), were studied using 20-kDa (n = 4) and 500-kDa (n = 4) FITC-dextran. In order to give a qualitative perspective...... of the general connection between the PCS and SCS, distribution of plasma-borne tracers (FITC-dextran) in the PCS and SCS were examined. In this study, a total of eight cod were cannulated in the ventral aorta (PCS) and dorsal cutaneous vessel (SCS), for investigation of FITC-dextran disappearance in the PCS...... and its subsequent appearance in the SCS. FITC-dextran of both sizes was found to be in equilibrium between the PCS and SCS in less than 20 min. This indicates a profound connection between the PCS and SCS in the Atlantic cod, and rapid mixing of tracers between the PCS and SCS. The destination...

  15. Impact of water-accommodated fractions of crude oil on Atlantic cod, Gadus morhua following chronic exposure

    International Nuclear Information System (INIS)

    Khan, R.

    2010-01-01

    This study examined the long-term effects of hydrocarbon exposure on the gonadal development of fish. Mature Atlantic cod (Gadus morhua) were exposed to low concentrations of water accommodated fractions (WAFs) of polycyclic aromatic hydrocarbons (PAHs) in an ambient flowthrough seawater system. Some PAH-exposed cod groups were depurated afterwards for 38 to 287 days. Mortality was rare, and external lesions occurred only in the PAH-exposed groups. The gonado-somatic index revealed that gonadal development was disrupted in both sexes and spawning and spermiation was delayed in the 33 depurated PAH-groups. The findings indicate that chronic exposure to WAFs in the water column may have an adverse effect on reproduction in Atlantic cod.

  16. Microbiological, chemical and sensory spoilage analysis of raw Atlantic cod (Gadus morhua) stored under modified atmospheres.

    Science.gov (United States)

    Kuuliala, L; Al Hage, Y; Ioannidis, A-G; Sader, M; Kerckhof, F-M; Vanderroost, M; Boon, N; De Baets, B; De Meulenaer, B; Ragaert, P; Devlieghere, F

    2018-04-01

    During fish spoilage, microbial metabolism leads to the production of volatile organic compounds (VOCs), characteristic off-odors and eventual consumer rejection. The aim of the present study was to contribute to the development of intelligent packaging technologies by identifying and quantifying VOCs that indicate spoilage of raw Atlantic cod (Gadus morhua) under atmospheres (%v/v CO 2 /O 2 /N 2 ) 60/40/0, 60/5/35 and air. Spoilage was examined by microbiological, chemical and sensory analyses over storage time at 4 or 8 °C. Selected-ion flow-tube mass spectrometry (SIFT-MS) was used for quantifying selected VOCs and amplicon sequencing of the 16S rRNA gene was used for the characterization of the cod microbiota. OTUs classified within the Photobacterium genus increased in relative abundance over time under all storage conditions, suggesting that Photobacterium contributed to spoilage and VOC production. The onset of exponential VOC concentration increase and sensory rejection occurred at high total plate counts (7-7.5 log). Monitoring of early spoilage thus calls for sensitivity for low VOC concentrations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Effects of dietary fatty acids on the production and quality of eggs and larvae of Atlantic cod (Gadus morhua L.)

    DEFF Research Database (Denmark)

    Røjbek, Maria; Støttrup, Josianne; Jacobsen, Charlotte

    2014-01-01

    Cultivated Atlantic cod (Gadus morhua) entering their first year of gamete maturation were fed diets with different levels of arachidonic acid (ARA) and eicosapentaenoic acid (EPA) for 6.5 months prior to commencement of spawning. Gravid females were stripped three times: at the beginning, peak......–173% higher in eggs than in diets. Cod fed the diet with the lowest EPA/ARA ratio had the greatest egg production. Eggs from fish on a diet with high ARA level had significantly higher fertilization and hatching success than those fed low levels of ARA. This diet produced on average 71 viable eggs g 1 female...

  18. Effects of ocean acidification increase embryonic sensitivity to thermal extremes in Atlantic cod, Gadus morhua.

    Science.gov (United States)

    Dahlke, Flemming T; Leo, Elettra; Mark, Felix C; Pörtner, Hans-Otto; Bickmeyer, Ulf; Frickenhaus, Stephan; Storch, Daniela

    2017-04-01

    Thermal tolerance windows serve as a powerful tool for estimating the vulnerability of marine species and their life stages to increasing temperature means and extremes. However, it remains uncertain to which extent additional drivers, such as ocean acidification, modify organismal responses to temperature. This study investigated the effects of CO 2 -driven ocean acidification on embryonic thermal sensitivity and performance in Atlantic cod, Gadus morhua, from the Kattegat. Fertilized eggs were exposed to factorial combinations of two PCO 2 conditions (400 μatm vs. 1100 μatm) and five temperature treatments (0, 3, 6, 9 and 12 °C), which allow identifying both lower and upper thermal tolerance thresholds. We quantified hatching success, oxygen consumption (MO 2 ) and mitochondrial functioning of embryos as well as larval morphometrics at hatch and the abundance of acid-base-relevant ionocytes on the yolk sac epithelium of newly hatched larvae. Hatching success was high under ambient spawning conditions (3-6 °C), but decreased towards both cold and warm temperature extremes. Elevated PCO 2 caused a significant decrease in hatching success, particularly at cold (3 and 0 °C) and warm (12 °C) temperatures. Warming imposed limitations to MO 2 and mitochondrial capacities. Elevated PCO 2 stimulated MO 2 at cold and intermediate temperatures, but exacerbated warming-induced constraints on MO 2 , indicating a synergistic interaction with temperature. Mitochondrial functioning was not affected by PCO 2 . Increased MO 2 in response to elevated PCO 2 was paralleled by reduced larval size at hatch. Finally, ionocyte abundance decreased with increasing temperature, but did not differ between PCO 2 treatments. Our results demonstrate increased thermal sensitivity of cod embryos under future PCO 2 conditions and suggest that acclimation to elevated PCO 2 requires reallocation of limited resources at the expense of embryonic growth. We conclude that ocean acidification

  19. Gastrointestinal microbial community changes in Atlantic cod (Gadus morhua) exposed to crude oil.

    Science.gov (United States)

    Bagi, Andrea; Riiser, Even Sannes; Molland, Hilde Steine; Star, Bastiaan; Haverkamp, Thomas H A; Sydnes, Magne Olav; Pampanin, Daniela Maria

    2018-04-02

    The expansion of offshore oil exploration increases the risk of marine species being exposed to oil pollution in currently pristine areas. The adverse effects of oil exposure through toxic properties of polycyclic aromatic hydrocarbons (PAHs) have been well studied in Atlantic cod (Gadus morhua). Nevertheless, the fate of conjugated metabolites in the intestinal tract and their effect on the diversity of intestinal microbial community in fish is less understood. Here, we investigated the intestinal microbial community composition of Atlantic cod after 28 days of exposure to crude oil (concentration range 0.0-0.1 mg/L). Analysis of PAH metabolites in bile samples confirmed that uptake and biotransformation of oil compounds occurred as a result of the exposure. Various evidence for altered microbial communities was found in fish exposed to high (0.1 mg/L) and medium (0.05 mg/L) concentrations of oil when compared to fish exposed to low oil concentration (0.01 mg/L) or no oil (control). First, altered banding patterns were observed on denaturing gradient gel electrophoresis for samples pooled from each treatment group. Secondly, based on 16S rRNA sequences, higher levels of oil exposure were associated with a loss of overall diversity of the gut microbial communities. Furthermore, 8 operational taxonomic units (OTUs) were found to have significantly different relative abundances in samples from fishes exposed to high and medium oil concentrations when compared to samples from the control group and low oil concentration. Among these, only one OTU, a Deferribacterales, had increased relative abundance in samples from fish exposed to high oil concentration. The results presented herein contribute to a better understanding of the effects of oil contamination on the gut microbial community changes in fish and highlight the importance of further studies into the area. Our findings suggest that increased relative abundance of bacteria belonging to the order

  20. Biomarker candidate discovery in Atlantic cod (Gadus morhua) continuously exposed to North Sea produced water from egg to fry

    DEFF Research Database (Denmark)

    Bohne-Kjersem, Anneli; Bache, Nicolai; Meier, Sonnich

    2010-01-01

    were able to compare the induced changes by PW to the mode of action of oestrogens. Changes in the proteome in response to exposure in whole cod fry (approximately 80 days post-hatching, dph) were detected by two-dimensional gel electrophoresis and image analysis and identified by MALDI-ToF-ToF mass...... spectrometry, using a newly developed cod EST database and the NCBI database. Many of the protein changes occurred at low levels (0.01% and 0.1% PW) of exposure, indicating putative biological responses at lower levels than previously detected. Using discriminant analysis, we identified a set of protein...... changes that may be useful as biomarker candidates of produced water (PW) and oestradiol exposure in Atlantic cod fry. The biomarker candidates discovered in this study may, following validation, prove effective as diagnostic tools in monitoring exposure and effects of discharges from the petroleum...

  1. Effects of chronic produced water exposure on the expression of some immune-related genes of juvenile Atlantic cod

    International Nuclear Information System (INIS)

    Perez Casanova, J.; Hamoutene, D.; Samuelson, S.; Burt, K.; King, T.; Lee, K.

    2010-01-01

    This study assessed the impacts of exposure to processed water produced by offshore oil operators on immune-related genes of juvenile Atlantic cod exposed to processed water for a period of 22 weeks. The study investigated the influence of processed water concentrations on growth parameters; food consumption; plasma cortisol; respiratory burst activity (RB); and mRNA expression. The study showed that the RB of circulating leukocytes was significantly elevated. Significant up-regulation of the mRNA expression of microglobulin, immunoglobulin light chain, and interleukins was observed in some fish. The down-regulation of the interferon stimulated gene was also observed. The study indicated that chronic exposure to significant amounts of processed water causes modulations of the immune system of juvenile Atlantic cod.

  2. Effects of chronic produced water exposure on the expression of some immune-related genes of juvenile Atlantic cod

    Energy Technology Data Exchange (ETDEWEB)

    Perez Casanova, J.; Hamoutene, D.; Samuelson, S.; Burt, K.; King, T. [Fisheries and Oceans Canada, St. John' s, NL (Canada); Lee, K. [Fisheries and Oceans Canada, Dartmouth, NS (Canada)

    2010-07-01

    This study assessed the impacts of exposure to processed water produced by offshore oil operators on immune-related genes of juvenile Atlantic cod exposed to processed water for a period of 22 weeks. The study investigated the influence of processed water concentrations on growth parameters; food consumption; plasma cortisol; respiratory burst activity (RB); and mRNA expression. The study showed that the RB of circulating leukocytes was significantly elevated. Significant up-regulation of the mRNA expression of microglobulin, immunoglobulin light chain, and interleukins was observed in some fish. The down-regulation of the interferon stimulated gene was also observed. The study indicated that chronic exposure to significant amounts of processed water causes modulations of the immune system of juvenile Atlantic cod.

  3. Low impact of exposure to environmentally relevant doses of 226Ra in Atlantic cod (Gadus morhua) embryonic cells

    International Nuclear Information System (INIS)

    Olsvik, Pål A.; Berntssen, Marc H.G.; Hylland, Ketil; Eriksen, Dag Ø.; Holen, Elisabeth

    2012-01-01

    The aim of this study was to investigate whether 226 Ra, a radionuclide present in produced water from oil platforms in the North Sea and other offshore drilling areas, could affect vulnerable early life stages of Atlantic cod (Gadus morhua). Blastula-stage embryonic cells (EC) from fertilized eggs of Atlantic cod were isolated and exposed to environmental relevant concentrations of 226 Ra and transcription of selected genes quantified. The results showed a weak, but significant up-regulation of GPx3 and HSP70 transcripts after 48 h of exposure to 2.11 Bq/L. In EC exposed to three 226 Ra concentrations (2.11, 23 and 117 Bq/L) for 12 h, metallothionein, HSP90AA, thioredoxin and caspase 8 were significantly up-regulated in cells exposed to 117 Bq/L, whereas thioredoxin was also significantly up-regulated in EC exposed to 23 Bq/L. When EC were exposed to the same 226 Ra concentrations for 48 h, only heme oxygenase was significantly up-regulated in the 23 Bq/L exposure group. The results suggest that environmentally relevant activities of 226 Ra may induce oxidative stress and apoptosis in fish ECs. Exposure of Atlantic cod EC to Cd, selected as a model toxicant, supported the ability of EC around blastula stage to respond to toxicants by altered transcription. Due to dilution, environmentally relevant concentrations of radionuclides present in produced water would be expected to pose a minor threat to early life stages of fish. - Highlights: ► 226 Ra affects the transcription of genes in Atlantic cod embryonic cells. ► 226 Ra may induce oxidative stress and apoptosis in fish embryonic cells. ► 226 Ra not expected to pose a major threat to early life stages of marine fish.

  4. Chronic CO2 exposure markedly increases the incidence of cataracts in juvenile Atlantic cod Gadus morhua L

    DEFF Research Database (Denmark)

    Moran, Damian; Tubbs, Lincoln; Støttrup, Josianne G.

    2012-01-01

    A study was undertaken to test the affect of chronic exposure to elevated dissolved carbon dioxide on juvenile Atlantic cod. The CO2 treatment concentrations were designated as low (1–2mgL−1, 1000μatm), medium (8mgL−1, 3500μatm) and high (18mgL−1, 8500μatm), and the fish were reared at 10°C and 2...

  5. Compounds of parasitic roundworm absorbing in the visible region: target molecules for detection of roundworm in Atlantic cod.

    Science.gov (United States)

    Stormo, Svein K; Ernstsen, Arild; Nilsen, Heidi; Heia, Karsten; Sivertsen, Agnar H; Elvevoll, Edel

    2004-07-01

    The objective of this study was to contribute to the development of technology that will be able to replace manual operations in processing of fish fillets. Removal of parasites, black lining, remnants of skin, and bloodstains are costly and time-consuming operations to the fish processing industry. The presence of parasites in fish products tends to spoil consumers' appetites. Recent reports questioning the safety of eating cod infected with parasites might lower consumer acceptance of seafood. Presently, parasites are detected and removed manually. An average efficiency of about 75% under commercial conditions has been reported. In this study, we focused on biochemical differences between cod muscle and the prevalent anisakine nematode species (Anisakis simplex and Pseudoterranova decipiens) infecting Atlantic cod (Gadus morhua). Using reversed phase high-performance liquid chromatography equipped with a photodiode array detector, substances absorbing in the range 300 to 600 nm were identified in extracts from parasite material. These substances were not detected in extracts from cod tissue. Significant biochemical differences between cod muscle and parasite material have thus been demonstrated.

  6. Temperature modulates the effects of ocean acidification on intestinal ion transport in Atlantic cod, Gadus morhua

    Directory of Open Access Journals (Sweden)

    Marian Yong-An Hu

    2016-06-01

    Full Text Available CO2-driven seawater acidification has been demonstrated to enhance intestinal bicarbonate secretion rates in teleosts, leading to an increased release of CaCO3 under simulated ocean acidification scenarios. In this study, we investigated if increasing CO2 levels stimulate the intestinal acid–base regulatory machinery of Atlantic cod (Gadus morhua and whether temperatures at the upper limit of thermal tolerance stimulate or counteract ion regulatory capacities. Juvenile G. morhua were acclimated for four weeks to three CO2 levels (550, 1,200 and 2,200 μatm covering present and near-future natural variability, at optimum (10°C and summer maximum temperature (18°C, respectively. Immunohistochemical analyses revealed the subcellular localization of ion transporters, including Na+/K+-ATPase (NKA, Na+/H+-exchanger 3 (NHE3, Na+/HCO3- cotransporter (NBC1, pendrin-like Cl-/HCO3- exchanger (SLC26a6, V-type H+-ATPase subunit a (VHA and Cl- channel 3 (CLC3 in epithelial cells of the anterior intestine. At 10°C, proteins and mRNA were generally up-regulated for most transporters in the intestinal epithelium after acclimation to higher CO2 levels. This supports recent findings demonstrating increased intestinal HCO3- secretion rates in response to CO2 induced seawater acidification. At 18°C, mRNA expression and protein concentrations of most ion transporters remained unchanged or were even decreased, suggesting thermal compensation. This response may be energetically favorable to retain blood HCO3- levels to stabilize pHe, but may negatively affect intestinal salt and water resorption of marine teleosts in future oceans.

  7. Effects of sex, stock, and environment on the shape of known-age Atlantic cod ( Gadus morhua ) otoliths

    DEFF Research Database (Denmark)

    Cardinale, M.; Doering-Arjes, P.; Kastowsky, M.

    2004-01-01

    The effects of sex, stock, and environment on the shape of known-age Atlantic cod (Gadus morhua) otoliths from the Faroe Islands were investigated. Moreover, the feasibility of otolith shape analysis for stock identification was evaluated. The shape was described by using several normalized Fourier...... descriptors and morphometric variables. There were no consistent differences between the left and right otoliths and between sexes within different age classes, stocks, and environments. With our experimental design, we could evaluate the relative importance of genetic and environmental conditions (water...... temperature and diet regime) on otolith shape and morphometrics. Using otolith shape, cod individuals were significantly separated into Bank and Plateau stocks. Total classification success was between 79% and 85% between stocks and between 85% and 96% between environments for the different age classes...

  8. Skeletal muscle growth dynamics and the influence of first-feeding diet in Atlantic cod larvae (Gadus morhua L.

    Directory of Open Access Journals (Sweden)

    Tu A. Vo

    2016-11-01

    Full Text Available Dynamics between hypertrophy (increase in cell size and hyperplasia (increase in cell numbers of white and red muscle in relation to body size [standard length (SL], and the influence of the first-feeding diets on muscle growth were investigated in Atlantic cod larvae (Gadus morhua. Cod larvae were fed copepod nauplii or rotifers of different nutritional qualities from 4 to 29 days post hatching (dph, Artemia nauplii from 20 to 40 dph and a formulated diet from 36 to 60 dph. The short period of feeding with cultivated copepod nauplii had a positive effect on both muscle hyperplasia and hypertrophy after the copepod/rotifer phase (19 dph, and a positive long term effect on muscle hypertrophy (60 dph. The different nutritional qualities of rotifers did not significantly affect muscle growth. We suggest here a model of the dynamics between hyperplasia and hypertrophy of red and white muscle fibre cells in relation to cod SL (4 to 30 mm, where the different red and white muscle growth phases clearly coincided with different metamorphosis stages in cod larvae. These shifts could be included as biomarkers for the different stages of development during metamorphosis. The main dietary muscle effect was that hypertrophic growth of red muscle fibres was stronger in cod larvae that were fed copepods than in larvae that were fed rotifers, both in relation to larval age and size. Red muscle fibres are directly involved in larval locomotory performance, but may also play an important role in the larval myogenesis. This can have a long term effect on growth potential and fish performance.

  9. Effects of amino acid supplementations on metabolic and physiological parameters in Atlantic cod (Gadus morhua) under stress.

    Science.gov (United States)

    Herrera, Marcelino; Herves, María Antonia; Giráldez, Inmaculada; Skar, Kristin; Mogren, Hanne; Mortensen, Atle; Puvanendran, Velmurugu

    2017-04-01

    The effects of tryptophan (Trp) and phenylalanine (Phe) diet supplementation on the stress and metabolism of the Atlantic cod have been studied. Fish were fed diet supplemented with Trp or Phe or control diet for 1 week. At the end of the feeding trial, fish were subjected to air exposure or heat shock. Following samples of blood, liver and muscle were taken from the fish and were analyzed for stress and metabolic indicators. After an air exposure, plasma cortisol levels in fish fed with Trp and Phe diets were lower compared to the fish fed the control diet. Diets containing both amino acids increased significantly the liver transaminase activities in juvenile cod. During thermal stress, high Trp contents had significant effects on fructose biphosphatase activity though Phe did not. Overall, activities of glucose 6-phosphate dehydrogenase, pyruvate kinase, and phosphofructokinase increased significantly for both amino acid diets. For the thermal stress, fish had the highest values of those activities for the 3Trp diet. Trp content in the diet had significant effects on the transaminase activity in muscle during air stress compared to fish fed control and Phe diets. Muscle alanine transaminase activity for thermal stress in fish fed any diet was not significantly different from the control. Both Trp and Phe supplementations reduced the stress markers in the cod; hence, they could be used as additives for the stress attenuation. However, they also raised the activity of key enzymes in glycolysis and gluconeogenesis, mainly the Trp diets.

  10. The responses of Atlantic cod (Gadus morhua L.) to ultrasound-emitting predators: stress, behavioural changes or debilitation?

    DEFF Research Database (Denmark)

    Schack, H.B.; Malte, H.; Madsen, Peter Teglberg

    2008-01-01

    A previous study has reported that Atlantic cod can be conditioned to detect ultrasonic sound pulses of high intensity. This capability has been proposed as a mean for detection and avoidance of echolocating toothed whales that emit intense ultrasonic clicks. In this study, we use acoustic...... exposed to ultrasonic clicks and echosounder pulses with received levels of more than 204 dB re. 1 µPa (pp) did not elicit flight responses as seen in ultrasound detecting Alosinae. Furthermore, we tested the debilitating effects of high intensity ultrasound on swimming cod with no detected changes...... playbacks to test the hypotheses that unconditioned cod can detect and respond to intense ultrasound from toothed whales and from echosounders. Intense ultrasound exposure of 210 dB re. 1µPa (pp) did not cause a short-term stress response in the form of bradycardia in unconditioned cod. Free-swimming cod...

  11. Cortisol levels and expression of selected stress- and apoptosis-related genes in the embryos of Atlantic cod, Gadus morhua following short-term exposure to air

    DEFF Research Database (Denmark)

    Marlowe, Christopher; Caipang, A.; Fagutao, Ferdinand F.

    2015-01-01

    Embryos (morula stage) of Atlantic cod, Gadus morhua L., were collected and subjected to air exposure for 2 min. followed by recovery at ambient conditions in the rearing container. Total immunoreactive cortisol and transcription of selected stress- and apoptosis-related genes of the embryos were...

  12. Evidence from data storage tags for the presence of lunar and semilunar behavioral cycles in spawning Atlantic cod

    Science.gov (United States)

    Grabowski, Timothy B.; McAdam, Bruce J.; Thorsteinsson, Vilhjalmur; Marteinsdóttir, Gudrún

    2015-01-01

    Understanding the environmental processes determining the timing and success of reproduction is of critical importance to developing effective management strategies of marine fishes. Unfortunately it has proven difficult to comprehensively study the reproductive behavior of broadcast-spawning fishes. The use of electronic data storage tags (DSTs) has the potential to provide insights into the behavior of fishes. These tags allow for data collection over relatively large spatial and temporal scales that can be correlated to predicted environmental conditions and ultimately be used to refine predictions of year class strength. In this paper we present data retrieved from DSTs demonstrating that events putatively identified as Atlantic cod spawning behavior is tied to a lunar cycle with a pronounced semi-lunar cycle within it. Peak activity occurs around the full and new moon with no evidence of relationship with day/night cycles.

  13. Growth of juvenile Atlantic cod Gadus morhua in land-based recirculation systems: Effects of feeding regime, photoperiod and diet

    DEFF Research Database (Denmark)

    Fülberth, Michael; Moran, Damian; Jarlbæk, Henrik

    2009-01-01

    The combined effect of feeding regime and photoperiod on the growth of juvenile Atlantic cod Gadus morhua in land-based recirculating aquaculture systems (RAS) was examined using three different commercial diets. Fish of 8–10 g were reared in 1 m3 tanks at an initial density of 10 kg m− 3 for 78 d....... Three RAS units were used to simultaneously test three feed/photoperiod regimes that might be encountered in the wild or aquaculture; LightDark (LD) 24:0, LD12:11 (+ 1 h crepuscular periods) and LD6:6 (+ 12 h crepuscular periods). Feed was administered during the light period every 30 min for a 3 min...... concentrations (photoperiod regime and diet on specific growth rate (SGR). Fish receiving the LD12:11 and LD6:6 regimes and Diet A grew best (SGR 2.59 and 2.54% d− 1 respectively). Fish...

  14. Size-dependent social attraction and repulsion explains the decision of Atlantic cod Gadus morhua to enter baited pots.

    Science.gov (United States)

    Anders, N; Fernö, A; Humborstad, O-B; Løkkeborg, S; Rieucau, G; Utne-Palm, A C

    2017-12-01

    The present study tested whether the presence of already retained fishes inside baited fish pots acted as a social attraction and affected the entrance probability of Atlantic cod Gadus morhua in a fjord in northern Norway. Video analysis revealed that the probability of an entrance initially increased with the presence of low numbers of fishes inside the pot, but subsequently decreased at a critical number of caught fishes. The critical number was dependent on the size of the G. morhua attempting to enter. This demonstrates that social attraction and repulsion play a role in G. morhua pot fishing and has important implications for the capture efficiency of fisheries executed with pots. © 2017 The Fisheries Society of the British Isles.

  15. Behavioural changes of Atlantic cod (Gadus morhua) after marine boulder reef restoration: Implications for coastal habitat management and Natura 2000 areas

    DEFF Research Database (Denmark)

    Støttrup, Josianne Gatt; Svendsen, Jon Christian; Stenberg, Claus

    2017-01-01

    While marine reefs are degraded globally, the responses of fish to marine reef restoration remain uncertain, particularly in temperate waters. This study measured the effect of marine boulder reef restoration on the behaviour of Atlantic cod, Gadus morhua L., in a Natura 2000 area using acoustic...... telemetry. Cod were tagged and released in the study area before and after the restoration and tracked continuously for six months. A larger fraction of the released fish remained in the study area after restoration (94%) than before (53%). Moreover, throughout the study period, cod spent significantly more...... hours per day and prolonged their residence time in the study area after the restoration. The study indicates that marine reefs subjected to boulder extraction can be restored and function as favourable cod habitats. Temperate marine boulder reef restoration represents a valuable management tool...

  16. A moderate increase in ambient temperature modulates the Atlantic cod (Gadus morhua spleen transcriptome response to intraperitoneal viral mimic injection

    Directory of Open Access Journals (Sweden)

    Hori Tiago S

    2012-08-01

    Full Text Available Abstract Background Atlantic cod (Gadus morhua reared in sea-cages can experience large variations in temperature, and these have been shown to affect their immune function. We used the new 20K Atlantic cod microarray to investigate how a water temperature change which, simulates that seen in Newfoundland during the spring-summer (i.e. from 10°C to 16°C, 1°C increase every 5 days impacted the cod spleen transcriptome response to the intraperitoneal injection of a viral mimic (polyriboinosinic polyribocytidylic acid, pIC. Results The temperature regime alone did not cause any significant increases in plasma cortisol levels and only minor changes in spleen gene transcription. However, it had a considerable impact on the fish spleen transcriptome response to pIC [290 and 339 significantly differentially expressed genes between 16°C and 10°C at 6 and 24 hours post-injection (HPI, respectively]. Seventeen microarray-identified transcripts were selected for QPCR validation based on immune-relevant functional annotations. Fifteen of these transcripts (i.e. 88%, including DHX58, STAT1, IRF7, ISG15, RSAD2 and IκBα, were shown by QPCR to be significantly induced by pIC. Conclusions The temperature increase appeared to accelerate the spleen immune transcriptome response to pIC. We found 41 and 999 genes differentially expressed between fish injected with PBS vs. pIC at 10°C and sampled at 6HPI and 24HPI, respectively. In contrast, there were 656 and 246 genes differentially expressed between fish injected with PBS vs. pIC at 16°C and sampled at 6HPI and 24HPI, respectively. Our results indicate that the modulation of mRNA expression of genes belonging to the NF-κB and type I interferon signal transduction pathways may play a role in controlling temperature-induced changes in the spleen’s transcript expression response to pIC. Moreover, interferon effector genes such as ISG15 and RSAD2 were differentially expressed between fish injected with

  17. Spatio-temporal dynamics of a fish predator: Density-dependent and hydrographic effects on Baltic Sea cod population.

    Directory of Open Access Journals (Sweden)

    Valerio Bartolino

    Full Text Available Understanding the mechanisms of spatial population dynamics is crucial for the successful management of exploited species and ecosystems. However, the underlying mechanisms of spatial distribution are generally complex due to the concurrent forcing of both density-dependent species interactions and density-independent environmental factors. Despite the high economic value and central ecological importance of cod in the Baltic Sea, the drivers of its spatio-temporal population dynamics have not been analytically investigated so far. In this paper, we used an extensive trawl survey dataset in combination with environmental data to investigate the spatial dynamics of the distribution of the Eastern Baltic cod during the past three decades using Generalized Additive Models. The results showed that adult cod distribution was mainly affected by cod population size, and to a minor degree by small-scale hydrological factors and the extent of suitable reproductive areas. As population size decreases, the cod population concentrates to the southern part of the Baltic Sea, where the preferred more marine environment conditions are encountered. Using the fitted models, we predicted the Baltic cod distribution back to the 1970s and a temporal index of cod spatial occupation was developed. Our study will contribute to the management and conservation of this important resource and of the ecosystem where it occurs, by showing the forces shaping its spatial distribution and therefore the potential response of the population to future exploitation and environmental changes.

  18. Infection levels and species diversity of ascaridoid nematodes in Atlantic cod, Gadus morhua, are correlated with geographic area and fish size

    DEFF Research Database (Denmark)

    Gay, M.; Bao, M.; MacKenzie, K.

    2018-01-01

    2012-2014.Prevalences for Anisakis in whole fish and in fillets in the different fishing areas varied from 16 to 100% and from 12 to 90% respectively. Abundance was also greatly influenced by the sampling area. Generalized additive model results indicate higher numbers of Anisakis in the North Sea......, C. osculatum and H. aduncum. In addition to high prevalence and abundance values, the cod sampled in this study presented a diversity of ascaridoid nematodes with a majority of fish displaying a co-infection. Out of 295 whole infected fish, 269 were co-infected by at least 2 genera.......Atlantic cod (Gadus morhua) is among the most important commercial fish species on the world market. Its infection by ascaridoid nematodes has long been known, Pseudoterranova even being named cod worm. In the present study, 755 individuals were sampled in the Barents, Baltic and North Seas during...

  19. Multi-decadal responses of a cod (Gadus morhua) population to human-induced trophic changes, fishing, and climate

    DEFF Research Database (Denmark)

    Eero, Margit; MacKenzie, Brian; Köster, Fritz

    2011-01-01

    to changes in fish populations can be analyzed with empirical data. In this study we investigate how climate variability and multiple human impacts (fishing, marine mammal hunting, eutrophication) have affected multi-decadal scale dynamics of cod in the Baltic Sea during the 20th century.We document...... significant climate-driven variations in cod recruitment production at multi-annual timescales, which had major impacts on population dynamics and the yields to commercial fisheries. We also quantify the roles of marine mammal predation, eutrophication, and exploitation on the development of the cod...

  20. Fertilisation and hatching success of Atlantic cod (Gadus morhua) eggs when exposed to various concentrations of produced water

    International Nuclear Information System (INIS)

    Wong, D.; Lyons, M.; Burridge, L.; Lee, K.

    2010-01-01

    This study investigated the fertilization and hatching success of Atlantic cod (Gadus morhua) eggs that were exposed to various dilutions of produced water from a natural gas production platform. A control group of eggs was fertilized in sea water without any produced water. Another set of eggs were fertilized in sea water with 4 different concentrations of produced water and held their respective concentrations for 24 hours to evaluate the success of the fertilization. Viable fertilized eggs were transferred to 96 well plates containing fresh sea water and incubated in the dark at approximately 6 degrees C until hatch. Eggs began hatching about 14 days after fertilization (DPF), peaked at about 17 DPF, then finished hatching by 21 DPF. Analysis of PAH content in the diluted produced water showed that at 0.32 percent, 1.08 percent and 3.6 percent concentrations, the fertilization success was greater than or equal to that of the control group. However, for the 12 percent concentration, there were no viable fertilized eggs present after the 24 hour period. Survivability of eggs during sea water incubation was similar for the 0 percent, 0.32 percent and 1.08 percent treatment groups, but egg mortality increased for the 3.60 percent concentration group, to about 61.5 percent mean cumulative mortality at 6 DPF, then remained constant. The mean hatching success for all dilutions was presented.

  1. Stable coexistence of genetically divergent Atlantic cod ecotypes at multiple spatial scales

    DEFF Research Database (Denmark)

    Knutsen, Halvor; Jorde, Per Erik; Hutchings, Jeffrey A.

    2018-01-01

    Coexistence in the same habitat of closely related yet genetically different populations is a phenomenon that challenges our understanding of local population structure and adaptation. Identifying the underlying mechanisms for such coexistence can yield new insight into adaptive evolution...

  2. The third serine proteinase with chymotrypsin specificity isolated from Atlantic cod (Gadus morhua) is a type-II elastase

    DEFF Research Database (Denmark)

    Asgeirsson, B; Leth-Larsen, Rikke; Thórólfsson, M

    1998-01-01

    -Ala-Ala-Pro-Phe-p-nitroanilide, but inactive against the typical elastase substrates succinyl-Ala-Ala-Ala-p-nitroanilide and orcein-elastin. Comparison of the kinetic properties of the cod elastase C with bovine chymotrypsin and cod chymotrypsin variants A and B, using succinyl-Ala-Ala-Pro-Phe-p-nitroanilide, showed a lower catalytic...

  3. Recent trends in the abundance of plaice Pleuronectes platessa and cod Gadus morhua in shallow coastal waters of the Northeastern Atlantic continental shelf – a review

    DEFF Research Database (Denmark)

    Dutz, Jörg; Støttrup, Josianne Gatt; Stenberg, Claus

    2016-01-01

    of the southern distribution boundary in the Bay of Biscay and deepening of stocks in the North Sea. In contrast, no trend in shallow water abundance of plaice similar to a decline in deep-water stocks during the 1970s and their slow recovery during the 2000s is apparent in the Skagerrak/Kattegat. Although......Shallow, near-shore water habitats on the continental shelf of the Northeast Atlantic have been productive fishing areas in the past. Here, we review the present knowledge about (i) recent trends in the abundance of plaice and cod in these habitats and (ii) hypotheses regarding the factors...... responsible for any trends. At present, only a few studies exist on the trends of abundance of plaice or cod, namely from the Bay of Biscay, the North Sea and the Skagerrak/Kattegat. They suggest a declining abundance in coastal, shallow areas and – at least for plaice – a latitudinal gradient with an erosion...

  4. Abolition of reflex bradycardia by cardiac vagotomy has no effect on the regulation of oxygen uptake by Atlantic cod in progressive hypoxia

    DEFF Research Database (Denmark)

    McKenzie, David; Skov, Peter Vilhelm; Taylor, E.W.T.

    2009-01-01

    The functional significance of chemoreflexive hypoxic bradycardia was explored in Atlantic cod Gadus morhua L. (mean mass similar to 800 g, acclimated to a seawater temperature of 11 degrees C) by investigating responses to progressive hypoxia following section of the cardiac branches of cranial...... nerve X Cardiac denervation had no effect on oxygen uptake rate (M-O2), gill ventilation rate (f(G)) or opercular pressure amplitude (P-OP) under normoxic conditions, but caused a significant increase in heart rate (f(H)), to 50 +/- 1 beats min(-1) by comparison to 40 +/- 2 beats min(-1) in sham...

  5. Seasonal variation in biomarkers in blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua)—Implications for environmental monitoring in the Barents Sea

    International Nuclear Information System (INIS)

    Nahrgang, J.; Brooks, S.J.; Evenset, A.; Camus, L.; Jonsson, M.; Smith, T.J.; Lukina, J.; Frantzen, M.; Giarratano, E.; Renaud, P.E.

    2013-01-01

    In the Barents Sea, the limited data on biological relevant indicators and their responses to various anthropogenic stressors have hindered the development of a consistent scientific basis for selecting indicator species and developing practical procedures for environmental monitoring. Accordingly, the main aim of the present study was to develop a common set of baseline values for contaminants and biomarkers in three species, and to identify their strengths and limitations in monitoring of the Barents Sea. Blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua) were sampled from a north Norwegian fjord in March, June, September and December 2010. Digestive glands from the bivalve species and liver from Atlantic cod were analysed for biomarkers of oxidative stress (catalase [CAT], glutathione peroxidase [GPX], glutathione-S-transferase activities [GST], lipid peroxidation as thiobarbituric reactive substances [TBARS] and total oxyradical scavenging capacity [TOSC]), biotransformation (ethoxyresorufine-O-deethylase activity [EROD]) and general stress (lysosomal membrane stability [LMS]). Concentrations of polycyclic aromatic hydrocarbons (PAHs) and metals in the bivalves and PAH metabolites in fish bile were quantified. Finally, energy reserves (total lipids, proteins and carbohydrates) and electron transport system (ETS) activity in the digestive gland of the bivalves and liver of Atlantic cod provided background information for reproductive cycle and general physiological status of the organisms. Blue mussel and Icelandic scallop showed very similar trends in biological cycle, biomarker expression and seasonality. Biomarker baselines in Atlantic cod showed weaker seasonal variability. However, important biological events may have been undetected due to the large time intervals between sampling occasions. Physiological biomarkers such as energy reserves and ETS activity were recommended as complementary parameters to the

  6. Seasonal variation in biomarkers in blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua)-Implications for environmental monitoring in the Barents Sea

    Energy Technology Data Exchange (ETDEWEB)

    Nahrgang, J., E-mail: jasmine.m.nahrgang@uit.no [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); Brooks, S.J. [Norwegian Institute for Water Research (NIVA), NO-0349 Oslo (Norway); Evenset, A. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); Camus, L. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); University Centre In Svalbard (UNIS), NO-9171 Longyearbyen (Norway); Jonsson, M.; Smith, T.J. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); Lukina, J. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); University of Tromso, Faculty of Biosciences, Fisheries and Economics, Department of Arctic and Marine Biosciences, NO-9037 Tromso (Norway); Frantzen, M. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); Giarratano, E. [Centro Nacional Patagonico (CENPAT-CONICET), AR-9120 Puerto Madryn (Argentina); Renaud, P.E. [Akvaplan-niva, FRAM Centre, NO-9296 Tromso (Norway); University Centre In Svalbard (UNIS), NO-9171 Longyearbyen (Norway)

    2013-02-15

    In the Barents Sea, the limited data on biological relevant indicators and their responses to various anthropogenic stressors have hindered the development of a consistent scientific basis for selecting indicator species and developing practical procedures for environmental monitoring. Accordingly, the main aim of the present study was to develop a common set of baseline values for contaminants and biomarkers in three species, and to identify their strengths and limitations in monitoring of the Barents Sea. Blue mussel (Mytilus edulis), Icelandic scallop (Chlamys islandica) and Atlantic cod (Gadus morhua) were sampled from a north Norwegian fjord in March, June, September and December 2010. Digestive glands from the bivalve species and liver from Atlantic cod were analysed for biomarkers of oxidative stress (catalase [CAT], glutathione peroxidase [GPX], glutathione-S-transferase activities [GST], lipid peroxidation as thiobarbituric reactive substances [TBARS] and total oxyradical scavenging capacity [TOSC]), biotransformation (ethoxyresorufine-O-deethylase activity [EROD]) and general stress (lysosomal membrane stability [LMS]). Concentrations of polycyclic aromatic hydrocarbons (PAHs) and metals in the bivalves and PAH metabolites in fish bile were quantified. Finally, energy reserves (total lipids, proteins and carbohydrates) and electron transport system (ETS) activity in the digestive gland of the bivalves and liver of Atlantic cod provided background information for reproductive cycle and general physiological status of the organisms. Blue mussel and Icelandic scallop showed very similar trends in biological cycle, biomarker expression and seasonality. Biomarker baselines in Atlantic cod showed weaker seasonal variability. However, important biological events may have been undetected due to the large time intervals between sampling occasions. Physiological biomarkers such as energy reserves and ETS activity were recommended as complementary parameters to the

  7. Regional changes in vertebra morphology during ontogeny reflect the life history of Atlantic cod (Gadus morhua L.)

    Science.gov (United States)

    Fjelldal, Per G; Totland, Geir K; Hansen, Tom; Kryvi, Harald; Wang, Xiyuan; Søndergaard, Jens L; Grotmol, Sindre

    2013-01-01

    This study examined vertebra formation, morphology, regional characters, and bending properties of the vertebral column of Atlantic cod throughout its life cycle (0–6 years). The first structure to form was the foremost neural arch, 21 days post hatching (dph), and the first vertebra centrum to form – as a chordacentrum – was the 3rd centrum at 28 dph. Thereafter, the notochord centra developed in a regular sequence towards the head and caudal fin. All vertebrae were formed within 50 dph. The vertebral column consisted of 52 (± 2) vertebrae (V) and could be divided into four distinct regions: (i) the cervical region (neck) (V1 and V2), characterized by short vertebra centra, prominent neural spines and absence of articulations with ribs; (ii) the abdominal region (trunk) (V3–V19), characterized by vertebrae with wing-shaped transverse processes (parapophyses) that all articulate with a rib; (iii) the caudal region (tail) (V20–V40), where the vertebra centra have haemal arches with prominent haemal spines; (iv) the ural region (V41 to the last vertebra), characterized by broad neural and haemal spines, providing sites of origin for muscles inserting on the fin rays – lepidotrichs – of the tail fin. The number of vertebrae in the cervical, abdominal and caudal regions was found to be constant, whereas in the ural region, numbers varied from 12 to 15. Geometric modelling based on combination of vertebra lengths, diameters and intervertebral distances showed an even flexibility throughout the column, except in the ural region, where flexibility increased. Throughout ontogeny, the vertebra centra of the different regions followed distinct patterns of growth; the relative length of the vertebrae increased in the cervical and abdominal regions, and decreased in the caudal and ural regions with increasing age. This may reflect changes in swimming mode with age, and/or that the production of large volumes of gametes during sexual maturation requires a

  8. An evaluation of the duration of efficacy of emamectin benzoate in the control of Caligus curtus Müller infestations in Atlantic cod, Gadus morhua L.

    Science.gov (United States)

    Hamre, L A; Lunestad, B T; Hannisdal, R; Samuelsen, O B

    2011-06-01

    The duration of efficacy of emamectin benzoate in the control of Caligus curtus infestations in Atlantic cod, Gadus morhua L., was studied following an administration of 50 μg kg⁻¹ for seven consecutive days. No lice were found on medicated fish when challenged 1 week (challenge 1) or 5 weeks (challenge 2) following termination of medication, whereas the mean abundance of lice among the unmedicated fish was 17.9 and 19.3 lice per fish in challenge 1 and 2, respectively. Muscle concentrations of 19.5 ± 8.2 ng g⁻¹ and 3.4 ± 0.9 ng g⁻¹, respectively, and skin concentrations of 23.1 ± 10.8 and 4.2 ± 1.0 ng g⁻¹, respectively, were found 27 and 55 days following the termination of medication. Tissue concentrations and the duration of efficacy indicate a dosing regime for emamectin in cod, similar to the regime used for Atlantic salmon, Salmo salar L. © 2011 Blackwell Publishing Ltd.

  9. Learning from ‘apparent consensus’ in TAC disputes: Exploring knowledge overlaps in LEK and genetic categorization of Atlantic cod

    DEFF Research Database (Denmark)

    Hedeholm, R. B.; Jacobsen, R. B.; Eg Nielsen, Einar

    2016-01-01

    and the corresponding genetic categories. However, an examination of existing inshore and off-shore catch surveys confirmed the relevance of the morphological characteristics (liver condition and shape) of ecologically defined inshore and off-shore cod that provided the basis for fishers' categorizations. This opens...

  10. Differential Survival among Batches of Atlantic Cod (Gadus morhua L. from Fertilisation through to Post-Metamorphosis.

    Directory of Open Access Journals (Sweden)

    Petra E Petersen

    Full Text Available Aquaculture production of cod has decreased from over 20,000 tonnes in 2009 to less than 2,000 tonnes in 2014 and the industry faces many challenges, one of which is high and unpredictably variable mortality rates in the early life stages. Hence, full-cycle farming with hatchery produced juveniles is still considered unprofitable compared to fisheries and on-growing of wild cod. In the present study, potential batch differences in progeny survival of wild-caught, hatchery-spawned Faroe Bank cod (Gadus morhua L. were investigated at two defined periods during early life history; i the embryo stage (60 day degrees post fertilisation and ii the fry stage (110 days post hatch, post metamorphosis. The fry stage experiment was conducted in three replicates (N = 300 per replicate, and a panel of three polymorphic microsatellite markers was used for parental analysis. Mean survival rate at the embryo stage was 69% (± 20% SD. Survival was positively associated with egg diameter (P < 0.01, explaining 90% of the variation in egg survival rates. The data were too scarce to conclude either way concerning a possible correlation between survival rates between the two periods (P < 0.10. Offspring from three batches (from a total of eight dominated in the fry stage, contributing over 90% of the progeny, and results were consistent over all three replicate tanks. The skewed batch representation observed may be of relevance to the effective management of selective breeding programmes for cod.

  11. HLA genes in Atlantic Celtic populations: are Celts Iberians? | Arnaiz ...

    African Journals Online (AJOL)

    Atlantic Europe populations were analyzed with HLA genes in order to establish their relationship among themselves and with other populations. Standard genetic and statistical software analyses were used. Celtic populations (British Isles and French Bretons) have genetically been found close together: Irish, Welsh, ...

  12. Northeast Regional Cod Tagging Program

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Scientific justification: Canadian and US stock assessments for Atlantic cod indicate considerable fluctuation in stock abundance and recruitment over the last 20...

  13. Industry Based Survey (IBS) Cod

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The "Gulf of Maine Atlantic Cod Industry-Based Survey" was a collaboration of the Massachusetts Division of Marine Fisheries and the fishing industry, with support...

  14. Population structure of Atlantic Mackerel (Scomber scombrus)

    DEFF Research Database (Denmark)

    Jansen, Teunis; Gislason, Henrik

    2013-01-01

    Atlantic mackerel (Scomber scombrus) occurs on both sides of the north Atlantic and has traditionally been grouped into 5 spawning components, some of which were thought to be isolated natal homing stocks. Previous studies have provided no evidence for cross Atlantic migration and no or weak...... between the North Sea and Celtic Sea, which indicates that the two spawning components may be connected by straying individuals. This finding is based on unique larvae samples collected before the collapse of North Sea component, thus showing that the exchange is not a recent phenomenon due...... to the collapse. The analyses of old as well as more recent age distributions show that strong year classes spread into other areas where they spawn as adults (“twinning”). Our findings are in accordance with the lack of solid evidence for stock separation from previous analyses of tagging data, genetics...

  15. Climate induced temperature effects on growth performance, fecundity and recruitment in marine fish: developing a hypothesis for cause and effect relationships in Atlantic cod ( Gadus morhua) and common eelpout ( Zoarces viviparus)

    Science.gov (United States)

    Pörtner, H. O.; Berdal, B.; Blust, R.; Brix, O.; Colosimo, A.; De Wachter, B.; Giuliani, A.; Johansen, T.; Fischer, T.; Knust, R.; Lannig, G.; Naevdal, G.; Nedenes, A.; Nyhammer, G.; Sartoris, F. J.; Serendero, I.; Sirabella, P.; Thorkildsen, S.; Zakhartsev, M.

    2001-12-01

    Effects of global warming on animal distribution and performance become visible in many marine ecosystems. The present study was designed to develop a concept for a cause and effect understanding with respect to temperature changes and to explain ecological findings based on physiological processes. The concept is based on a wide comparison of invertebrate and fish species with a special focus on recent data obtained in two model species of fish. These fish species are both characterized by northern and southern distribution limits in the North Atlantic: eelpout ( Zoarces viviparus), as a typical non-migrating inhabitant of the coastal zone and the cod ( Gadus morhua), as a typical inhabitant of the continental shelf with a high importance for fisheries. Mathematical modelling demonstrates a clear significant correlation between climate induced temperature fluctuations and the recruitment of cod stocks. Growth performance in cod is optimal at temperatures close to 10°C, regardless of the population investigated in a latitudinal cline. However, temperature specific growth rates decrease at higher latitudes. Also, fecundity is less in White Sea than in North and Baltic Sea cod or eelpout populations. These findings suggest that a cold-induced shift in energy budget occurs which is unfavorable for growth performance and fecundity. Thermal tolerance limits shift depending on latitude and are characterized by oxygen limitation at both low or high temperatures. Oxygen supply to tissues is optimized at low temperature by a shift in hemoglobin isoforms and oxygen binding properties to lower affinities and higher unloading potential. Protective stimulation of heat shock protein synthesis was not observed. According to a recent model of thermal tolerance the downward shift of tolerance limits during cold adaptation is associated with rising mitochondrial densities and, thus, aerobic capacity and performance in the cold, especially in eurythermal species. At the same time

  16. Conditions for instant electrical stunning of farmed Atlantic cod after de-watering, maintenance of unconsciousness, effects of stress, and fillet quality — A comparison with AQUI-S™

    NARCIS (Netherlands)

    Erikson, U.; Lambooij, E.; Digre, H.; Reimert, H.G.M.; Bondø, M.; Vis, van de H.

    2012-01-01

    Electrical stunning of farmed Atlantic cod is a method used to render the fish unconscious before further processing. However, evaluations of the stunning method at plants have shown that the electrical parameters need to be optimized to achieve instant stunning and prolonged duration of

  17. Changes in regional brain monoaminergic activity and temporary down-regulation in stress response from dietary supplementation with l-tryptophan in Atlantic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Basic, D.; Schjolden, J.; Krogdahl, A.

    2013-01-01

    . Previous studies in teleosts demonstrate that 7 d of dietary administration with l-tryptophan (Trp), the direct precursor of 5-HT, suppresses the endocrine stress response. The present study investigated how long the suppressive effects of a Trp-enriched feed regimen, at doses corresponding to two, three......The brain monoamines serotonin (5-hydroxytryptamine; 5-HT) and dopamine (DA) both play an integrative role in behavioural and neuroendocrine responses to challenges, and comparative models suggest common mechanisms for dietary modulation of transmission by these signal substances in vertebrates...... or four times the Trp levels in commercial feed, last in juvenile Atlantic cod (Gadus morhua) when the fish are reintroduced to a diet with standard amino acid composition. We also wanted to determine whether Trp supplementation induced changes in brain monoaminergic neurochemistry in those forebrain...

  18. Quantitative proteomics analysis reveals perturbation of lipid metabolic pathways in the liver of Atlantic cod (Gadus morhua) treated with PCB 153.

    Science.gov (United States)

    Yadetie, Fekadu; Oveland, Eystein; Døskeland, Anne; Berven, Frode; Goksøyr, Anders; Karlsen, Odd André

    2017-04-01

    PCB 153 is one of the most abundant PCB congeners detected in biological samples. It is a persistent compound that is still present in the environment despite the ban on production and use of PCBs in the late 1970s. It has strong tendencies to bioaccumulate and biomagnify in biota, and studies have suggested that it is an endocrine and metabolic disruptor. In order to study mechanisms of toxicity, we exposed Atlantic cod (Gadus morhua) to various doses of PCB 153 (0, 0.5, 2 and 8mg/kg body weight) for two weeks and examined the effects on expression of liver proteins using label-free quantitative proteomics. Label-free liquid chromatography-mass spectrometry analysis of the liver proteome resulted in the quantification of 1272 proteins, of which 78 proteins were differentially regulated in the PCB 153-treated dose groups compared to the control group. Functional enrichment analysis showed that pathways significantly affected are related to lipid metabolism, cytoskeletal remodeling, cell cycle and cell adhesion. Importantly, the main effects appear to be on lipid metabolism, with up-regulation of enzymes in the de novo fatty acid synthesis pathway, consistent with previous transcriptomics results. Increased plasma triglyceride levels were also observed in the PCB 153 treated fish, in agreement with the induction of the lipogenic genes and proteins. The results suggest that PCB 153 perturbs lipid metabolism in the Atlantic cod liver. Elevated levels of lipogenic enzymes and plasma triglycerides further suggest increased synthesis of fatty acids and triglycerides. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. The Ontogeny and Brain Distribution Dynamics of the Appetite Regulators NPY, CART and pOX in Larval Atlantic Cod (Gadus morhua L.).

    Science.gov (United States)

    Le, Hoang T M D; Angotzi, Anna Rita; Ebbesson, Lars O E; Karlsen, Ørjan; Rønnestad, Ivar

    2016-01-01

    Similar to many marine teleost species, Atlantic cod undergo remarkable physiological changes during the early life stages with concurrent and profound changes in feeding biology and ecology. In contrast to the digestive system, very little is known about the ontogeny and the localization of the centers that control appetite and feed ingestion in the developing brain of fish. We examined the expression patterns of three appetite regulating factors (orexigenic: neuropeptide Y, NPY; prepro-orexin, pOX and anorexigenic: cocaine- and amphetamine-regulated transcript, CART) in discrete brain regions of developing Atlantic cod using chromogenic and double fluorescent in situ hybridization. Differential temporal and spatial expression patterns for each appetite regulator were found from first feeding (4 days post hatch; dph) to juvenile stage (76 dph). Neurons expressing NPY mRNA were detected in the telencephalon (highest expression), diencephalon, and optic tectum from 4 dph onward. CART mRNA expression had a wider distribution along the anterior-posterior brain axis, including both telencephalon and diencephalon from 4 dph. From 46 dph, CART transcripts were also detected in the olfactory bulb, region of the nucleus of medial longitudinal fascicle, optic tectum and midbrain tegmentum. At 4 and 20 dph, pOX mRNA expression was exclusively found in the preoptic region, but extended to the hypothalamus at 46 and 76 dph. Co-expression of both CART and pOX genes were also observed in several hypothalamic neurons throughout larval development. Our results show that both orexigenic and anorexigenic factors are present in the telencephalon, diencephalon and mesencephalon in cod larvae. The telencephalon mostly contains key factors of hunger control (NPY), while the diencephalon, and particularly the hypothalamus may have a more complex role in modulating the multifunctional control of appetite in this species. As the larvae develop, the overall progression in temporal and

  20. The Ontogeny and Brain Distribution Dynamics of the Appetite Regulators NPY, CART and pOX in Larval Atlantic Cod (Gadus morhua L..

    Directory of Open Access Journals (Sweden)

    Hoang T M D Le

    Full Text Available Similar to many marine teleost species, Atlantic cod undergo remarkable physiological changes during the early life stages with concurrent and profound changes in feeding biology and ecology. In contrast to the digestive system, very little is known about the ontogeny and the localization of the centers that control appetite and feed ingestion in the developing brain of fish. We examined the expression patterns of three appetite regulating factors (orexigenic: neuropeptide Y, NPY; prepro-orexin, pOX and anorexigenic: cocaine- and amphetamine-regulated transcript, CART in discrete brain regions of developing Atlantic cod using chromogenic and double fluorescent in situ hybridization. Differential temporal and spatial expression patterns for each appetite regulator were found from first feeding (4 days post hatch; dph to juvenile stage (76 dph. Neurons expressing NPY mRNA were detected in the telencephalon (highest expression, diencephalon, and optic tectum from 4 dph onward. CART mRNA expression had a wider distribution along the anterior-posterior brain axis, including both telencephalon and diencephalon from 4 dph. From 46 dph, CART transcripts were also detected in the olfactory bulb, region of the nucleus of medial longitudinal fascicle, optic tectum and midbrain tegmentum. At 4 and 20 dph, pOX mRNA expression was exclusively found in the preoptic region, but extended to the hypothalamus at 46 and 76 dph. Co-expression of both CART and pOX genes were also observed in several hypothalamic neurons throughout larval development. Our results show that both orexigenic and anorexigenic factors are present in the telencephalon, diencephalon and mesencephalon in cod larvae. The telencephalon mostly contains key factors of hunger control (NPY, while the diencephalon, and particularly the hypothalamus may have a more complex role in modulating the multifunctional control of appetite in this species. As the larvae develop, the overall progression in

  1. Early life of key fish species, capelin Mallotus villosus and Atlantic cod Gadus morhua, in West Greenland

    DEFF Research Database (Denmark)

    Malanski, Evandro

    for the fish larvae during the summer. The duration of the productive season is of great importance for the early life of fish. The present thesis investigates the diets of capelin and cod in the subarctic Kapisigdlit, as well as the feeding of non-commercial larval fish in the entire Godthåbsfjord system...... species were found in the area, and 3 main assemblages were identified according to their similarities, which are related to the hydrographic zones. Fish larvae may benefit from the estuarine circulation to distribute themselves from the spawning areas through the Godthåbsfjord. The diet of the larval...... fish species varied markedly along the fjord. Prey size preferences of fish larvae were positively correlated to their mouth sizes. American plaice and sandeel were probably do not compete for food with other fish species since these, contrary to other species, had high preference for microplankton...

  2. Computer vision-based evaluation of pre- and postrigor changes in size and shape of Atlantic cod (Gadus morhua) and Atlantic salmon (Salmo salar) fillets during rigor mortis and ice storage: effects of perimortem handling stress.

    Science.gov (United States)

    Misimi, E; Erikson, U; Digre, H; Skavhaug, A; Mathiassen, J R

    2008-03-01

    The present study describes the possibilities for using computer vision-based methods for the detection and monitoring of transient 2D and 3D changes in the geometry of a given product. The rigor contractions of unstressed and stressed fillets of Atlantic salmon (Salmo salar) and Atlantic cod (Gadus morhua) were used as a model system. Gradual changes in fillet shape and size (area, length, width, and roundness) were recorded for 7 and 3 d, respectively. Also, changes in fillet area and height (cross-section profiles) were tracked using a laser beam and a 3D digital camera. Another goal was to compare rigor developments of the 2 species of farmed fish, and whether perimortem stress affected the appearance of the fillets. Some significant changes in fillet size and shape were found (length, width, area, roundness, height) between unstressed and stressed fish during the course of rigor mortis as well as after ice storage (postrigor). However, the observed irreversible stress-related changes were small and would hardly mean anything for postrigor fish processors or consumers. The cod were less stressed (as defined by muscle biochemistry) than the salmon after the 2 species had been subjected to similar stress bouts. Consequently, the difference between the rigor courses of unstressed and stressed fish was more extreme in the case of salmon. However, the maximal whole fish rigor strength was judged to be about the same for both species. Moreover, the reductions in fillet area and length, as well as the increases in width, were basically of similar magnitude for both species. In fact, the increases in fillet roundness and cross-section height were larger for the cod. We conclude that the computer vision method can be used effectively for automated monitoring of changes in 2D and 3D shape and size of fish fillets during rigor mortis and ice storage. In addition, it can be used for grading of fillets according to uniformity in size and shape, as well as measurement of

  3. Substitution of fish oil with camelina oil and inclusion of camelina meal in diets fed to Atlantic cod (Gadus morhua) and their effects on growth, tissue lipid classes, and fatty acids.

    Science.gov (United States)

    Hixson, S M; Parrish, C C

    2014-03-01

    Developing a commercially relevant Atlantic cod aquaculture industry will require improvements in feed sustainability. Camelina oil and meal are potential replacements of fish oil and fish meal in aquaculture feeds. Camelina oil is high in 18:3ω3 (30%), with an ω3/ω6 ratio > 1. Camelina meal has a considerable crude protein level (38%), which includes significant amounts of methionine and phenylalanine. Four diets were tested; each diet was fed to triplicate tanks (3 tanks per diet) of Atlantic cod (14.4 g/fish; 70 fish per tank) for 13 wk. The diets included a fish oil/fish meal control (FO) and three diets which replaced 100% of fish oil with camelina oil: one diet contained fish meal (100CO), another solvent extracted fish meal (100COSEFM), and another had fish meal partially reduced by 15% inclusion of camelina meal (100CO15CM). Growth was measured (length and weight) and tissue samples were collected for lipid analysis (muscle, liver, brain, gut, spleen, skin, and carcass) at wk 0 (before feeding the experimental diet) and at wk 13. Cod fed camelina oil had a lower (P replacement of fish oil with camelina oil, plus solvent extracted fish meal had an overarching effect on the entire fatty acid profile of the whole animal. Fatty acid mass balance calculations indicated that cod fed 100COSEFM elongated 13% of 18:3ω3 to 20:3ω3 and oxidized the remaining 87%, whereas cod fed fish oil showed a much lower (P meal caused the greatest change in cod lipid composition and utilization.

  4. Connectivity, persistence, and loss of high abundance areas of a recovering marine fish population in the Northwest Atlantic Ocean.

    Science.gov (United States)

    Boudreau, Stephanie A; Shackell, Nancy L; Carson, Stuart; den Heyer, Cornelia E

    2017-11-01

    In the early 1990s, the Northwest Atlantic Ocean underwent a fisheries-driven ecosystem shift. Today, the iconic cod ( Gadus morhua ) remains at low levels, while Atlantic halibut ( Hippoglossus hippoglossus ) has been increasing since the mid-2000s, concomitant with increasing interest from the fishing industry. Currently, our knowledge about halibut ecology is limited, and the lack of recovery in other collapsed groundfish populations has highlighted the danger of overfishing local concentrations. Here, we apply a Bayesian hierarchical spatiotemporal approach to model the spatial structure of juvenile Atlantic halibut over 36 years and three fisheries management regimes using three model parameters to characterize the resulting spatiotemporal abundance structure: persistence (similarity of spatial structure over time), connectivity (coherence of temporal pattern over space), and spatial variance (variation across the seascape). Two areas of high juvenile abundance persisted through three decades whereas two in the northeast are now diminished, despite the increased abundance and landings throughout the management units. The persistent areas overlap with full and seasonal area closures, which may act as refuges from fishing. Connectivity was estimated to be 250 km, an order of magnitude less than the distance assumed by the definition of the Canadian management units (~2,000 km). The underlying question of whether there are distinct populations within the southern stock unit cannot be answered with this model, but the smaller ~250 km scale of coherent temporal patterns suggests more complex population structure than previously thought, which should be taken into consideration by fishery management.

  5. Modeling growth of Atlantic cod larvae on the southern flank of Georges Bank in the tidal-front circulation during May 1999

    Science.gov (United States)

    Lough, R. G.; Broughton, E. A.; Buckley, L. J.; Incze, L. S.; Pehrson Edwards, K.; Converse, R.; Aretxabaleta, A.; Werner, F. E.

    2006-11-01

    Cruises were conducted in spring 1999 to describe the interaction between tidal-front processes and the transport, retention, and growth of cod larvae and their prey during the seasonal transition to a stratified water-column along the southern flank of Georges Bank. All the physical and biological observations were integrated in coupled circulation-trophodynamic simulations. The three-dimensional circulation fields were modeled using data assimilation methods described in Aretxabaleta et al. [2005. Data assimilative hindcast on the Southern Flank of Georges Bank during May 1999: frontal circulation and implications. Continental Shelf Research 25, 849-874]. The individual-based model (IBM) of Lough et al. [2005. A general biophysical model of larval cod growth applied to populations on Georges Bank. Fisheries Oceanography 14, 241-262] was used to consider trophodynamic effects on the growth and survival of larval cod. Prey fields were specified for mixed and stratified water columns from field surveys and allowed to adjust in the circulation model. Encounter and ingestion rates of larvae were functions of prey concentration, larval search patterns, light, swimming speeds of predator and prey, and turbulence. Model outputs provide hourly depth-dependent estimates of growth rates, prey biomass ingested, and larval length and weight. Simulations were conducted along a 2-D transect across the tidal front, from mixed to stratified water columns, before and after a wind event. Pre-storm, observed larval cod growth rates, based on RNA-DNA analysis, were highest in the surface 20 m at the stratified and front stations. Post-storm, larval growth rates decreased 1-2% d -1 at the stratified and front stations, corresponding with a <1 °C decrease in temperature. At the mixed station, there was no apparent difference in growth rates with depth, either before or after the storm. Simulations indicate that maximum larval growth rates can occur at the tidal-mixing front due to the

  6. Optimized conditions for primary culture of pituitary cells from the Atlantic cod (Gadus morhua). The importance of osmolality, pCO₂, and pH.

    Science.gov (United States)

    Hodne, Kjetil; von Krogh, Kristine; Weltzien, Finn-Arne; Sand, Olav; Haug, Trude M

    2012-09-01

    Protocols for primary cultures of teleost cells are commonly only moderately adjusted from similar protocols for mammalian cells, the main adjustment often being of temperature. Because aquatic habitats are in general colder than mammalian body temperatures and teleosts have gills in direct contact with water, pH and buffer capacity of blood and extracellular fluid are different in fish and mammals. Plasma osmolality is generally higher in marine teleosts than in mammals. Using Atlantic cod (Gadus morhua) as a model, we have optimized these physiological parameters to maintain primary pituitary cells in culture for an extended period without loosing key properties. L-15 medium with adjusted osmolality, adapted to low pCO(2) (3.8mm Hg) and temperature (12°C), and with pH 7.85, maintained the cells in a physiologically sounder state than traditional culture medium, significantly improving cell viability compared to the initial protocol. In the optimized culture medium, resting membrane potential and response to releasing hormone were stable for at least two weeks, and the proportion of cells firing action potentials during spawning season was about seven times higher than in the original culture medium. The cells were moderately more viable when the modified medium was supplemented with newborn calf serum or artificial serum substitute. Compared to serum-free L-15 medium, expression of key genes (lhb, fshb, and gnrhr2a) was better maintained in medium containing SSR, whereas NCS tended to decrease the expression level. Although serum-free medium is adequate for many applications, serum supplement may be preferable for experiments dependent on membrane integrity. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. How cod shapes its world

    NARCIS (Netherlands)

    van Leeuwen, A.; de Roos, A.M.; Persson, L.

    2008-01-01

    Cod stocks in the North West Atlantic and the Baltic Sea have shown similar dynamics in recent decades with a rapid decline in abundance and a lack of stock recovery following a period of large biomass. We explore whether the lack of recovery can be ascribed to an emergent Allee effect, which is a

  8. Otolith shape: a population marker for Atlantic herring Clupea harengus.

    Science.gov (United States)

    Libungan, L A; Óskarsson, G J; Slotte, A; Jacobsen, J A; Pálsson, S

    2015-04-01

    Otolith shape variation of seven Atlantic herring Clupea harengus populations from Canada, the Faroe Islands, Iceland, Ireland, Norway and Scotland, U.K., covering a large area of the species' distribution, was studied in order to see if otolith shape can be used to discriminate between populations. The otolith shape was obtained using quantitative shape analysis, transformed with Wavelet and analysed with multivariate methods. Significant differences were detected among the seven populations, which could be traced to three morphological structures in the otoliths. The differentiation in otolith shape between populations was not only correlated with their spawning time, indicating a strong environmental effect, but could also be due to differing life-history strategies. A model based on the shape differences discriminates with 94% accuracy between Icelandic summer spawners and Norwegian spring spawners, which are known to mix at feeding grounds. This study shows that otolith shape could become an accurate marker for C. harengus population discrimination. © 2015 The Fisheries Society of the British Isles.

  9. Genomics of Arctic cod

    Science.gov (United States)

    Wilson, Robert E.; Sage, George K.; Sonsthagen, Sarah A.; Gravley, Megan C.; Menning, Damian; Talbot, Sandra L.

    2017-01-01

    The Arctic cod (Boreogadus saida) is an abundant marine fish that plays a vital role in the marine food web. To better understand the population genetic structure and the role of natural selection acting on the maternally-inherited mitochondrial genome (mitogenome), a molecule often associated with adaptations to temperature, we analyzed genetic data collected from 11 biparentally-inherited nuclear microsatellite DNA loci and nucleotide sequence data from from the mitochondrial DNA (mtDNA) cytochrome b (cytb) gene and, for a subset of individuals, the entire mitogenome. In addition, due to potential of species misidentification with morphologically similar Polar cod (Arctogadus glacialis), we used ddRAD-Seq data to determine the level of divergence between species and identify species-specific markers. Based on the findings presented here, Arctic cod across the Pacific Arctic (Bering, Chukchi, and Beaufort Seas) comprise a single panmictic population with high genetic diversity compared to other gadids. High genetic diversity was indicated across all 13 protein-coding genes in the mitogenome. In addition, we found moderate levels of genetic diversity in the nuclear microsatellite loci, with highest diversity found in the Chukchi Sea. Our analyses of markers from both marker classes (nuclear microsatellite fragment data and mtDNA cytb sequence data) failed to uncover a signal of microgeographic genetic structure within Arctic cod across the three regions, within the Alaskan Beaufort Sea, or between near-shore or offshore habitats. Further, data from a subset of mitogenomes revealed no genetic differentiation between Bering, Chukchi, and Beaufort seas populations for Arctic cod, Saffron cod (Eleginus gracilis), or Walleye pollock (Gadus chalcogrammus). However, we uncovered significant differences in the distribution of microsatellite alleles between the southern Chukchi and central and eastern Beaufort Sea samples of Arctic cod. Finally, using ddRAD-Seq data, we

  10. 50 CFR 226.217 - Critical habitat for the Gulf of Maine Distinct Population Segment of Atlantic Salmon (Salmo salar).

    Science.gov (United States)

    2010-10-01

    ... Distinct Population Segment of Atlantic Salmon (Salmo salar). 226.217 Section 226.217 Wildlife and... Distinct Population Segment of Atlantic Salmon (Salmo salar). Critical habitat is designated to include all... the Gulf of Maine Distinct Population Segment of Atlantic Salmon (GOM DPS), except for those...

  11. Stable isotopes indicate population structuring in the southwest Atlantic population of right whales (Eubalaena australis.

    Directory of Open Access Journals (Sweden)

    Morgana Vighi

    Full Text Available From the early 17th century to the 1970s southern right whales, Eubalaena australis, were subject to intense exploitation along the Atlantic coast of South America. Catches along this coast recorded by whalers originally formed a continuum from Brazil to Tierra del Fuego. Nevertheless, the recovery of the population has apparently occurred fragmentarily, and with two main areas of concentration, one off southern Brazil (Santa Catarina and another off central Argentina (Peninsula Valdés. This pattern suggests some level of heterogeneity amongst the population, which is apparently contradicted by records that traced individuals moving throughout the whole geographical extension covered by the species in the Southwest Atlantic. To test the hypothesis of the potential occurrence of discrete subpopulations exploiting specific habitats, we investigated N, C and O isotopic values in 125 bone samples obtained from whaling factories operating in the early 1970s in southern Brazil (n=72 and from contemporary and more recent strandings occurring in central Argentina (n=53. Results indicated significant differences between the two sampling areas, being δ13C and δ18O values significantly higher in samples from southern Brazil than in those from central Argentina. This variation was consistent with isotopic baselines from the two areas, indicating the occurrence of some level of structure in the Southwest Atlantic right whale population and equally that whales more likely feed in areas commonly thought to exclusively serve as nursing grounds. Results aim at reconsidering of the units currently used in the management of the southern right whale in the Southwest Atlantic Ocean. In the context of the current die-off affecting the species in Peninsula Valdés, these results also highlight the necessity to better understand movements of individuals and precisely identify their feeding areas.

  12. Temporal trends in age and size at maturation of four North Sea gadid populations: cod, haddock, whiting, and Norway pout

    DEFF Research Database (Denmark)

    Marty, Lise; Rochet, Marie-Joëlle; Ernande, Bruno

    2014-01-01

    , phenotypic plasticity, and evolution to these trends were assessed. First, maturation trends were extricated from demographic effects and growth-dependent plasticity by estimating probabilistic maturation reaction norms (PMRNs). PMRN midpoints have significantly shifted downwards at most ages for cod......, haddock, and whiting, but not for Norway pout. Second, increased temperature and food abundance, loosened trophic competition, and relaxed social pressure may also trigger growth-independent plasticity in maturation. Principal component regression of PMRN midpoints on annual estimates of relevant...... environmental variables exhibiting a temporal trend suggest that, despite some evidence of environmental effects, PMRN trends were mostly independent of growth-independent plasticity in haddock, whiting, and male cod, but not in female cod. According to these findings, evolution of maturation, potentially...

  13. Ocelot Population Status in Protected Brazilian Atlantic Forest.

    Science.gov (United States)

    Massara, Rodrigo Lima; Paschoal, Ana Maria de Oliveira; Doherty, Paul Francis; Hirsch, André; Chiarello, Adriano Garcia

    2015-01-01

    Forest fragmentation and habitat loss are detrimental to top carnivores, such as jaguars (Panthera onca) and pumas (Puma concolor), but effects on mesocarnivores, such as ocelots (Leopardus pardalis), are less clear. Ocelots need native forests, but also might benefit from the local extirpation of larger cats such as pumas and jaguars through mesopredator release. We used a standardized camera trap protocol to assess ocelot populations in six protected areas of the Atlantic forest in southeastern Brazil where over 80% of forest remnants are forest cover, number of free-ranging domestic dogs and presence of top predators. Ocelot abundance was positively correlated with reserve size and the presence of top predators (jaguar and pumas) and negatively correlated with the number of dogs. We also found higher detection probabilities in less forested areas as compared to larger, intact forests. We suspect that smaller home ranges and higher movement rates in smaller, more degraded areas increased detection. Our data do not support the hypothesis of mesopredator release. Rather, our findings indicate that ocelots respond negatively to habitat loss, and thrive in large protected areas inhabited by top predators.

  14. Ocelot Population Status in Protected Brazilian Atlantic Forest.

    Directory of Open Access Journals (Sweden)

    Rodrigo Lima Massara

    Full Text Available Forest fragmentation and habitat loss are detrimental to top carnivores, such as jaguars (Panthera onca and pumas (Puma concolor, but effects on mesocarnivores, such as ocelots (Leopardus pardalis, are less clear. Ocelots need native forests, but also might benefit from the local extirpation of larger cats such as pumas and jaguars through mesopredator release. We used a standardized camera trap protocol to assess ocelot populations in six protected areas of the Atlantic forest in southeastern Brazil where over 80% of forest remnants are < 50 ha. We tested whether variation in ocelot abundance could be explained by reserve size, forest cover, number of free-ranging domestic dogs and presence of top predators. Ocelot abundance was positively correlated with reserve size and the presence of top predators (jaguar and pumas and negatively correlated with the number of dogs. We also found higher detection probabilities in less forested areas as compared to larger, intact forests. We suspect that smaller home ranges and higher movement rates in smaller, more degraded areas increased detection. Our data do not support the hypothesis of mesopredator release. Rather, our findings indicate that ocelots respond negatively to habitat loss, and thrive in large protected areas inhabited by top predators.

  15. Injection-salting and cold-smoking of farmed atlantic cod (Gadus morhua L.) and Atlantic salmon (Salmo salar L.) at different stages of Rigor Mortis: effect on physical properties.

    Science.gov (United States)

    Akse, L; Birkeland, S; Tobiassen, T; Joensen, S; Larsen, R

    2008-10-01

    Processing of fish is generally conducted postrigor, but prerigor processing is associated with some potential advantages. The aim of this study was to study how 5 processing regimes of cold-smoked cod and salmon conducted at different stages of rigor influenced yield, fillet shrinkage, and gaping. Farmed cod and salmon was filleted, salted by brine injection of 25% NaCl, and smoked for 2 h at different stages of rigor. Filleting and salting prerigor resulted in increased fillet shrinkage and less increase in weight during brine injection, which in turn was correlated to the salt content of the fillet. These effects were more pronounced in cod fillets when compared to salmon. Early processing reduced fillet gaping and fillets were evaluated as having a firmer texture. In a follow-up trial with cod, shrinkage and weight gain during injection was studied as an effect of processing time postmortem. No changes in weight gain were observed for fillets salted the first 24 h postmortem; however, by delaying the processing 12 h postmortem, the high and rapid shrinking of cod fillets during brine injection was halved.

  16. Cod Liver Oil

    Science.gov (United States)

    Cod liver oil can be obtained from eating fresh cod liver or by taking supplements. Cod liver oil is used as a source of vitamin A ... called macular degeneration. Some people put cod liver oil on their skin to speed healing of wounds, ...

  17. CHARACTERIZATION OF WESTERN NORTH ATLANTIC RIGHT WHALE SPRING FEEDING HABITAT

    Science.gov (United States)

    The Great South Channel region of the southwestern Gulf of Maine, between George's Bank and Cape Cod, is the primary spring feeding ground for the western North Atlantic population of the I northern right whale, E. glacialis .Since this whale is so endangered, it is critical to i...

  18. Effects of temperature and population density on von Bertalanffy growth parameters in Atlantic herring: a macro-ecological analysis

    NARCIS (Netherlands)

    Brunel, T.P.A.; Dickey-Collas, M.

    2010-01-01

    The effect of temperature and population density on the growth of Atlantic herring Clupea harengus was studied using a comparative approach applied to 15 North Atlantic populations. The von Bertalanffy (VB) equation was applied to describe mean growth of individuals in each population, both averaged

  19. Genetic structure of European populations of Salmo salar L (Atlantic salmon) inferred from mitochondrial DNA

    DEFF Research Database (Denmark)

    Eg Nielsen, Einar; Hansen, Michael Møller; Loeschcke, V.

    1996-01-01

    The genetic relationships between the only natural population of Atlantic salmon (Salmo salar L.) in Denmark and seven other European salmon populations were studied using RFLP analysis of PCR amplified mitochondrial DNA segments. Six different haplotypes were detected by restriction enzyme...

  20. Microgeographical population structure and adaptation in Atlantic cod Gadus morhua: spatio-temporal insights from gene-associated DNA markers

    DEFF Research Database (Denmark)

    Poulsen, Nina Aagaard; Hemmer-Hansen, Jakob; Loeschcke, V.

    2011-01-01

    levels of genetic differentiation. Interestingly, these loci were identical to loci previously found to display signals of adaptive evolution on larger spatial scales. Analysis of historical samples revealed long-term temporally stable patterns of both neutral and adaptive divergence between some...

  1. Phylogeography and population dynamics of the white-sided dolphin (Lagenorhynchus acutus) in the North Atlantic

    KAUST Repository

    Banguera-Hinestroza, E.; Evans, P. G H; Mirimin, L.; Reid, R. J.; Mikkelsen, B.; Couperus, A. S.; Deaville, R.; Rogan, E.; Hoelzel, A. R.

    2014-01-01

    Highly mobile species in the marine environment may be expected to show little differentiation at the population level, but this is often not the case. Instead cryptic population structure is common, and effective conservation will require an understanding of how these patterns evolve. Here we present an assessment from both sides of the North Atlantic of differentiation among populations of a dolphin species that inhabits mainly pelagic waters, the Atlantic white-sided dolphin. We compare eleven putative populations in the western and eastern North Atlantic at mtDNA and microsatellite DNA loci and find reduced nucleotide diversity and signals for historical bottlenecks and post-bottleneck expansions in all regions. We calculate expansion times to have occurred during the early Holocene, following the last glacial maximum (LGM). We find evidence for connectivity among populations from either side of the North Atlantic, and differentiation between putative populations in the far northeast compared with all other areas sampled. Some data suggest the possibility of separate refugia during the LGM explaining this pattern, although ongoing ecological processes may also be a factor. We discuss the implications for developing effective programs of conservation and management in the context of ongoing anthropogenic impact. © 2014 Springer Science+Business Media Dordrecht.

  2. Phylogeography and population dynamics of the white-sided dolphin (Lagenorhynchus acutus) in the North Atlantic

    KAUST Repository

    Banguera-Hinestroza, E.

    2014-02-27

    Highly mobile species in the marine environment may be expected to show little differentiation at the population level, but this is often not the case. Instead cryptic population structure is common, and effective conservation will require an understanding of how these patterns evolve. Here we present an assessment from both sides of the North Atlantic of differentiation among populations of a dolphin species that inhabits mainly pelagic waters, the Atlantic white-sided dolphin. We compare eleven putative populations in the western and eastern North Atlantic at mtDNA and microsatellite DNA loci and find reduced nucleotide diversity and signals for historical bottlenecks and post-bottleneck expansions in all regions. We calculate expansion times to have occurred during the early Holocene, following the last glacial maximum (LGM). We find evidence for connectivity among populations from either side of the North Atlantic, and differentiation between putative populations in the far northeast compared with all other areas sampled. Some data suggest the possibility of separate refugia during the LGM explaining this pattern, although ongoing ecological processes may also be a factor. We discuss the implications for developing effective programs of conservation and management in the context of ongoing anthropogenic impact. © 2014 Springer Science+Business Media Dordrecht.

  3. Stable isotopes provide insight into population structure and segregation in eastern North Atlantic sperm whales

    DEFF Research Database (Denmark)

    Borrell, Asunción; Velásquez Vacca, Adriana; Pinela, Ana M.

    2013-01-01

    In pelagic species inhabiting large oceans, genetic differentiation tends to be mild and populations devoid of structure. However, large cetaceans have provided many examples of structuring. Here we investigate whether the sperm whale, a pelagic species with large population sizes and reputedly......, use of habitat and/or migratory destinations are dissimilar between whales from the two regions and suggest that the North Atlantic population of sperm whales is more structured than traditionally accepted....

  4. Towards sustainable fisheries of the Öresund cod (Gadus morhua) through sub-stock-specific assessment and management recommendations

    DEFF Research Database (Denmark)

    Lindegren, Martin; Waldo, Staffan; Nilsson, P. Anders

    2013-01-01

    Fisheries management traditionally relies on stock assessments assuming discrete populations within large administrational areas. However, failing to account for sub-stock structuring may result in overestimation of the stocks' true harvest potential and unsustainable exploitation of small stock...... elements. Atlantic cod (Gadus morhua) frequently occurs in spatially segregated populations, some of which exhibit fine-scaled stock structuring within current management boundaries. Here we use the locally spawning cod stock in the Sound (“Öresund”) as a case study, and perform a sub-stock......-specific assessment to evaluate biological and economic effects of managing the Sound cod as a separate stock. Our results indicate that reducing exploitation pressure, particularly through technical regulations i.e. increasing gill-net mesh sizes, would not only enhance the stock age distribution, but yield long...

  5. The Population Consequences of Disturbance Model Application to North Atlantic Right Whales (Eubalaena glacialis)

    Science.gov (United States)

    2015-09-30

    physiology, and the revised approach is called PCOD (Population Consequences Of Disturbance). In North Atlantic right whales (Eubalaena glacialis...acoustic disturbance and prey variability into the PCOD model. OBJECTIVES The objectives for this study are to: 1) develop a Hierarchical...the model to assessing the effects of acoustics on the population. We have refined and applied the PCOD model developed for right whales (Schick et

  6. Microbial populations and activities of mangrove, restinga and Atlantic forest soils from Cardoso Island, Brazil.

    Science.gov (United States)

    Pupin, B; Nahas, E

    2014-04-01

    Mangroves provide a distinctive ecological environment that differentiates them from other ecosystems. This study deal to evaluate the frequency of microbial groups and the metabolic activities of bacteria and fungi isolated from mangrove, restinga and Atlantic forest soils. Soil samples were collected during the summer and winter at depths of 0-2, 2-5 and 5-10 cm. Except for fungi, the counts of the total, sporulating, Gram-negative, actinomycetes, nitrifying and denitrifying bacteria decreased significantly in the following order: Atlantic forest >mangrove > restinga. The counts of micro-organisms decreased by 11 and 21% from the surface to the 2-5 and 5-10 cm layers, but denitrifying bacteria increased by 44 and 166%, respectively. A larger growth of micro-organisms was verified in the summer compared with the winter, except for actinomycetes and fungi. The average frequency of bacteria isolated from mangrove, restinga and Atlantic forest soils was 95, 77 and 78%, and 93, 90 and 95% for fungi, respectively. Bacteria were amylolytic (33%), producers of acid phosphatase (79%) and solubilizers (18%) of inorganic phosphate. The proportions of fungi were 19, 90 and 27%. The mangrove soil studied had higher chemical characteristics than the Atlantic forest, but the high salinity may have restricted the growth of microbial populations. Estimates of the microbial counts and activities were important to elucidate the differences of mangrove ecosystem from restinga and Atlantic forest. © 2013 The Society for Applied Microbiology.

  7. Population Structure and Dispersal Patterns within and between Atlantic and Mediterranean Populations of a Large-Range Pelagic Seabird

    Science.gov (United States)

    Genovart, Meritxell; Thibault, Jean-Claude; Igual, José Manuel; Bauzà-Ribot, Maria del Mar; Rabouam, Corinne; Bretagnolle, Vincent

    2013-01-01

    Dispersal is critically linked to the demographic and evolutionary trajectories of populations, but in most seabird species it may be difficult to estimate. Using molecular tools, we explored population structure and the spatial dispersal pattern of a highly pelagic but philopatric seabird, the Cory's shearwater Calonectris diomedea. Microsatellite fragments were analysed from samples collected across almost the entire breeding range of the species. To help disentangle the taxonomic status of the two subspecies described, the Atlantic form C. d. borealis and the Mediterranean form C. d. diomedea, we analysed genetic divergence between subspecies and quantified both historical and recent migration rates between the Mediterranean and Atlantic basins. We also searched for evidence of isolation by distance (IBD) and addressed spatial patterns of gene flow. We found a low genetic structure in the Mediterranean basin. Conversely, strong genetic differentiation appeared in the Atlantic basin. Even if the species was mostly philopatric (97%), results suggest recent dispersal between basins, especially from the Atlantic to the Mediterranean (aprox. 10% of migrants/generation across the last two generations). Long-term gene flow analyses also suggested an historical exchange between basins (about 70 breeders/generation). Spatial analysis of genetic variation indicates that distance is not the main factor in shaping genetic structure in this species. Given our results we recommend gathering more data before concluded whether these taxa should be treated as two species or subspecies. PMID:23950986

  8. Footprints of directional selection in wild Atlantic salmon populations: evidence for parasite-driven evolution?

    Science.gov (United States)

    Zueva, Ksenia J; Lumme, Jaakko; Veselov, Alexey E; Kent, Matthew P; Lien, Sigbjørn; Primmer, Craig R

    2014-01-01

    Mechanisms of host-parasite co-adaptation have long been of interest in evolutionary biology; however, determining the genetic basis of parasite resistance has been challenging. Current advances in genome technologies provide new opportunities for obtaining a genome-scale view of the action of parasite-driven natural selection in wild populations and thus facilitate the search for specific genomic regions underlying inter-population differences in pathogen response. European populations of Atlantic salmon (Salmo salar L.) exhibit natural variance in susceptibility levels to the ectoparasite Gyrodactylus salaris Malmberg 1957, ranging from resistance to extreme susceptibility, and are therefore a good model for studying the evolution of virulence and resistance. However, distinguishing the molecular signatures of genetic drift and environment-associated selection in small populations such as land-locked Atlantic salmon populations presents a challenge, specifically in the search for pathogen-driven selection. We used a novel genome-scan analysis approach that enabled us to i) identify signals of selection in salmon populations affected by varying levels of genetic drift and ii) separate potentially selected loci into the categories of pathogen (G. salaris)-driven selection and selection acting upon other environmental characteristics. A total of 4631 single nucleotide polymorphisms (SNPs) were screened in Atlantic salmon from 12 different northern European populations. We identified three genomic regions potentially affected by parasite-driven selection, as well as three regions presumably affected by salinity-driven directional selection. Functional annotation of candidate SNPs is consistent with the role of the detected genomic regions in immune defence and, implicitly, in osmoregulation. These results provide new insights into the genetic basis of pathogen susceptibility in Atlantic salmon and will enable future searches for the specific genes involved.

  9. Long-term species balance in sympatric populations: implications for Atlantic salmon and brown trout

    Directory of Open Access Journals (Sweden)

    Jose Luis Horreo

    2014-09-01

    Full Text Available The factors determining regional adaptation in salmonids are still unclear, but it is known that changes in their habitat imply changes in their population structure. In this preliminary study we integrate habitat data, molecular analyses (from both nuclear microsatellite and mitochondrial loci and life-history traits (measured on archaeological vertebrae and modern scales of two sympatric salmonid species: Atlantic salmon and brown trout. We propose that water temperature and geological characteristics changed the biogeographic patterns of these species through asymmetric migration and different (but complementary population growth rates. As a consequence, differences in a life-history trait (mean number of years at sea and population sizes were detected between regions, suggesting a process of substitution of Atlantic salmon by brown trout.

  10. Cod Gadus morhua and climate change: processes, productivity and prediction

    DEFF Research Database (Denmark)

    Brander, Keith

    2010-01-01

    the causes. Investigation of cod Gadus morhua populations across the whole North Atlantic Ocean has shown large-scale patterns of change in productivity due to lower individual growth and condition, caused by large-scale climate forcing. If a population is being heavily exploited then a drop in productivity......Environmental factors act on individual fishes directly and indirectly. The direct effects on rates and behaviour can be studied experimentally and in the field, particularly with the advent of ever smarter tags for tracking fishes and their environment. Indirect effects due to changes in food......, predators, parasites and diseases are much more difficult to estimate and predict. Climate can affect all life-history stages through direct and indirect processes and although the consequences in terms of growth, survival and reproductive output can be monitored, it is often difficult to determine...

  11. Ancient DNA reveals the Arctic origin of Viking Age cod from Haithabu, Germany.

    Science.gov (United States)

    Star, Bastiaan; Boessenkool, Sanne; Gondek, Agata T; Nikulina, Elena A; Hufthammer, Anne Karin; Pampoulie, Christophe; Knutsen, Halvor; André, Carl; Nistelberger, Heidi M; Dierking, Jan; Petereit, Christoph; Heinrich, Dirk; Jakobsen, Kjetill S; Stenseth, Nils Chr; Jentoft, Sissel; Barrett, James H

    2017-08-22

    Knowledge of the range and chronology of historic trade and long-distance transport of natural resources is essential for determining the impacts of past human activities on marine environments. However, the specific biological sources of imported fauna are often difficult to identify, in particular if species have a wide spatial distribution and lack clear osteological or isotopic differentiation between populations. Here, we report that ancient fish-bone remains, despite being porous, brittle, and light, provide an excellent source of endogenous DNA (15-46%) of sufficient quality for whole-genome reconstruction. By comparing ancient sequence data to that of modern specimens, we determine the biological origin of 15 Viking Age (800-1066 CE) and subsequent medieval (1066-1280 CE) Atlantic cod ( Gadus morhua ) specimens from excavation sites in Germany, Norway, and the United Kingdom. Archaeological context indicates that one of these sites was a fishing settlement for the procurement of local catches, whereas the other localities were centers of trade. Fish from the trade sites show a mixed ancestry and are statistically differentiated from local fish populations. Moreover, Viking Age samples from Haithabu, Germany, are traced back to the North East Arctic Atlantic cod population that has supported the Lofoten fisheries of Norway for centuries. Our results resolve a long-standing controversial hypothesis and indicate that the marine resources of the North Atlantic Ocean were used to sustain an international demand for protein as far back as the Viking Age.

  12. HLA Genes in Atlantic Celtic populations: Are Celts Iberians?

    African Journals Online (AJOL)

    toshiba

    Islanders (Scottish), French Bretons, Galicians, Spanish Basques, Portuguese, cluster together in DA genetic distances, correspondence analysis and Neighbour Joining dendrograms. Genetics have been shown by itself not suffice to determine populations migration/relatedness. Aristotle and Herodotus placed Celts in ...

  13. Early life of an inshore population of West Greenlandic cod Gadus morhua: spatial and temporal aspects of growth and survival

    DEFF Research Database (Denmark)

    Swalethorp, Rasmus; Nielsen, Torkel Gissel; Thompson, A. R.

    2016-01-01

    Understanding the processes that affect fish larval survival and recruitment is a fundamental tenant of fisheries science. Small, isolated fjords are ideal study systems for elucidating early life history processes, as population dynamics are well traced in these partially closed systems. We exam...

  14. Environmental contaminants in fillets of sea-run Atlantic salmon (Salmo salar) from the Gulf of Maine Distinct Population Segment

    Data.gov (United States)

    Department of the Interior — Between 2008 and 2010, skin‐on fillets from seven dead adult sea‐run Atlantic salmon from the Gulf of Maine Distinct Population Segment (GOM DPS) were analyzed for...

  15. Population genetic structure in Atlantic and Pacific Ocean common murres (Uria aalge): Natural replicate tests of post-Pleistocene evolution

    Science.gov (United States)

    Morris-Pocock, J. A.; Taylor, S.A.; Birt, T.P.; Damus, M.; Piatt, John F.; Warheit, K.I.; Friesen, Vicki L.

    2008-01-01

    Understanding the factors that influence population differentiation in temperate taxa can be difficult because the signatures of both historic and contemporary demographics are often reflected in population genetic patterns. Fortunately, analyses based on coalescent theory can help untangle the relative influence of these historic and contemporary factors. Common murres (Uria aalge) are vagile seabirds that breed in the boreal and low arctic waters of the Northern Hemisphere. Previous analyses revealed that Atlantic and Pacific populations are genetically distinct; however, less is known about population genetic structure within ocean basins. We employed the mitochondrial control region, four microsatellite loci and four intron loci to investigate population genetic structure throughout the range of common murres. As in previous studies, we found that Atlantic and Pacific populations diverged during the Pleistocene and do not currently exchange migrants. Therefore, Atlantic and Pacific murre populations can be used as natural replicates to test mechanisms of population differentiation. While we found little population genetic structure within the Pacific, we detected significant east-west structuring among Atlantic colonies. The degree that population genetic structure reflected contemporary population demographics also differed between ocean basins. Specifically, while the low levels of population differentiation in the Pacific are at least partially due to high levels of contemporary gene flow, the east-west structuring of populations within the Atlantic appears to be the result of historic fragmentation of populations rather than restricted contemporary gene flow. The contrasting results in the Atlantic and Pacific Oceans highlight the necessity of carefully considering multilocus nonequilibrium population genetic approaches when reconstructing the demographic history of temperate Northern Hemisphere taxa. ?? 2008 The Authors.

  16. Distribution and population structure of North Atlantic harbour seals (Phoca vitulina

    Directory of Open Access Journals (Sweden)

    Liselotte Andersen

    2010-09-01

    Full Text Available A review of the known geographical distribution and current knowledge on the genetic population structure of harbour seals (Phoca vitulina in the North Atlantic is presented. Based on a synthesis of the results fromfive different studies of neutral geneticmarkers (mtDNAand nuclear microsatellites, mainly twelve genetically distinct populations were identified in the North Atlantic: USA/Canada, Iceland, west coast of Norway, Ireland-Scotland, English east coast, Channel area, Wadden Sea, Limfjord, Skagerrak, Kattegat, West Baltic, and East Baltic. Most of the studies addressed the population structure at the regional level, while only a few addressed the structuring at a local level, i.e. within countries. Due to the limited number of studies conducted, the identified population units were considered preliminary andmore detailed, local studieswould probably reveal structuring on a finer scale. The choice of genetic markers, their properties, resolution in time and applicability in population structure studies is shortly discussed and compared to ecological methods used to delineate populations.

  17. Implications of stock recovery for a neighbouring management unit: experience from the Baltic cod

    DEFF Research Database (Denmark)

    Eero, Margit; Hansen, Jakob Hemmer; Hüssy, Karin

    2014-01-01

    Cod in the Baltic Sea is assessed and managed as two separate stocks, i.e. eastern and western Baltic cod. The eastern Baltic cod has recently started to recover after several decades of severe depletion. In the present study, we suggest that the recovery of the eastern Baltic cod population has ...

  18. Pre-hospital ticagrelor in ST-segment elevation myocardial infarction in the French ATLANTIC population

    DEFF Research Database (Denmark)

    Cayla, Guillaume; Lapostolle, Frederic; Ecollan, Patrick

    2017-01-01

    BACKGROUND: ATLANTIC was a randomized study comparing pre- and in-hospital treatment with a ticagrelor loading dose (LD) in ongoing ST-segment elevation myocardial infarction (STEMI). We sought to compare patient characteristics and clinical outcomes in France with other countries participating...... in ATLANTIC. METHODS: The population comprised 1862 patients, 660 (35.4%) from France and 1202 from 12 other countries. The main endpoints were reperfusion (≥70% ST-segment elevation resolution) and TIMI flow grade 3 before (co-primary endpoints) and after percutaneous coronary intervention (PCI). Other...... endpoints included a composite ischaemic endpoint (death/myocardial infarction/stroke/urgent revascularization/definite stent thrombosis) and bleeding events at 30days. RESULTS: In France, median times from first LD to angiography and between first and second LDs were 49 and 35min, respectively, and were...

  19. Genomic differentiation and demographic histories of Atlantic and Indo-Pacific yellowfin tuna (Thunnus albacares) populations.

    Science.gov (United States)

    Barth, J M I; Damerau, M; Matschiner, M; Jentoft, S; Hanel, R

    2017-04-13

    Recent developments in the field of genomics have provided new and powerful insights into population structure and dynamics that are essential for the conservation of biological diversity. As a commercially highly valuable species, the yellowfin tuna (Thunnus albacares) is intensely exploited throughout its distribution in tropical oceans around the world, and is currently classified as near threatened. However, conservation efforts for this species have so far been hampered by limited knowledge of its population structure, due to incongruent results of previous investigations. Here, we use whole-genome sequencing in concert with a draft genome assembly to decipher the global population structure of the yellowfin tuna, and to investigate its demographic history. We detect significant differentiation of Atlantic and Indo-Pacific yellowfin tuna populations as well as the possibility of a third diverged yellowfin tuna group in the Arabian Sea. We further observe evidence for past population expansion as well as asymmetric gene flow from the Indo-Pacific to the Atlantic. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  20. Genetic diversity of Casearia sylvestris populations in remnants of the Atlantic Forest.

    Science.gov (United States)

    Araujo, F L; Siqueira, M V B M; Grando, C; Viana, J P G; Pinheiro, J B; Alves-Pereira, A; Campos, J B; Brancalion, P H S; Zucchi, M I

    2017-01-23

    Guaçatonga (Casearia sylvestris) is a native plant of the Atlantic Forest, with high medicinal potential and relevance for reforestation programs. The aim of this study was to characterize, with microsatellite markers, two populations of C. sylvestris from remaining areas of the Atlantic Forest in the State of São Paulo. High allelic variation was found in both populations (N A = 101 and 117; A R = 12.5 and 14.4), although with high endogamy coefficients (f = 0.640 and 0.363). Estimates of genetic structure suggested the presence of considerable genetic divergence between the populations (F ST = 0.103); however, there was no spatial genetic structure within the populations. Genetic divergence may have occurred due to decreased gene flow between the fragmented populations as the result of deforestation. The results of this study demonstrate the importance of genetic diversity and its characterization in native plants within remaining forest areas for the management and restoration of such areas.

  1. Genetic structure analysis of Eufriesea violacea (Hymenoptera, Apidae populations from southern Brazilian Atlantic rainforest remnants

    Directory of Open Access Journals (Sweden)

    Silvia H. Sofia

    2005-09-01

    Full Text Available Random amplified polymorphic DNA (RAPD markers were used to analyze the genetic structure of Eufriesea violacea populations in three fragments (85.47, 832.58 and 2800 ha of Atlantic rainforest located in the north of the Brazilian state of Paraná. A total of twelve primers produced 206 loci, of which 129 were polymorphic (95% criterion. The proportions of polymorphic loci in each population ranged from 57.28% to 59.2%, revealing very similar levels of genetic variability in the groups of bees from each fragment. Unbiased genetic distances between groups ranged from 0.0171 to 0.0284, the smallest genetic distance occurring between bees from the two larger fragments. These results suggest that the E. violacea populations from the three fragments have maintained themselves genetically similar to native populations of this species originally present in northern Paraná.

  2. Geologic history of Cape Cod, Massachusetts

    Science.gov (United States)

    ,

    1976-01-01

    Cape Cod, a sandy peninsula built mostly during the Ice Age, juts into the Atlantic Ocean like a crooked arm. Because of its exposed location, Cape Cod was visited by many early explorers. Although clear-cut evidence is lacking, the Vikings may have sighted this land about 1,000 years ago. It was visited by Samuel de Champlain in 1605, and his detailed descriptions and charts have helped present-day scientists to determine the rate of growth of Nauset Beach marsh and Nauset spit. Bartholomew Gosnold, a lesser known explorer, settled for a short time on the Elizabeth Islands to the southwest and gave Cape Cod its name in 1602. The Pilgrims first landed in America on the tip of Lower Cape Cod after they were turned back from their more southerly destination by shoals between Cape Cod and Nantucket Island. On Cape Cod they found potable water and food and had their first fight with the natives. The Pilgrims, however, decided that this land was too isolated, too exposed, and too sandy to support them, and they sailed across Cape Cod Bay to establish Plymouth. These features remain today. Small villages are separated by large areas of forest, dune, beach, and marsh. This unspoiled natural beauty makes Cape Cod one of the most favored vacation areas for the people living in the thickly settled Northeastern States. Cape Cod is of particular interest to geologists because it was formed by glaciers very recently in terms of geologic time. During the Great Ice Age, (the Pleistocene Epoch which began 2 to 3 million years ago), glaciers advanced from the north into the temperate regions of the Earth. Glacial ice covered the land at least four times. Each advance was accompanied by a worldwide lowering of sea level because the source of the ice was water from the seas. When the glaciers melted, the climate and sea level were probably much like they are today. In fact, some scientists believe that the Earth is presently between glacial episodes and that ice once again will

  3. Genetic diversity, kinship analysis, and broodstock management of captive Atlantic sturgeon for population restoration

    Science.gov (United States)

    Henderson, A.P.; Spidle, A.P.; King, T.L.

    2005-01-01

    Captive Atlantic sturgeon Acipenser oxyrinchus considered for use as broodstock in a restoration program were genotyped using nuclear DNA microsatellites and compared to wild collections from the Hudson River, New York (source of parents of the captive sturgeon) and from Albemarle Sound, North Carolina. Because the potential broodfish were the progeny of a small number of parents, maintaining genetic diversity and minimizing inbreeding is essential to a successful breeding and supplementation program. The microsatellite loci used in this analysis generated unique multilocus genotypes for each of 136 Atlantic sturgeon. Analyses indicated significant genetic separation between the New York and North Carolina collections and correctly identified the potential broodstock as a subset of the Hudson River population. Pairwise genetic distance (-In proportion of shared alleles) between half and full siblings in the potential broodfish was as great as 1.386, a value exceeded by only 36% of the sampled broodfish pairs available for mating. Because the current broodstock population does not seem to have deviated far from their ancestral population in the Hudson River, progeny from that broodstock, or the parents themselves, would seem to be genetically suitable for release back into the Hudson River.

  4. Marginal/peripheral populations of forest tree species and their conservation status: report for Atlantic region

    Directory of Open Access Journals (Sweden)

    Colin T. Kelleher

    2018-04-01

    Full Text Available This report is a synthesis of information from the national reports, prepared as part of the COST Action FP1202 Strengthening conservation: a key issue for adaptation of marginal/peripheral populations of forest trees to climate change in Europe (MaPFGR. The individual national reports can be found as part of the supplemental data to the COST action. The data compiled in this report indicate that the Atlantic area has sufficient resources in terms of knowledge and capacity to assess the potential impact of climate change on marginal and peripheral (MaP sites within the area. Maps of vegetation, soil, climate and climatic predictions are publicly available for most countries and often are of high quality and resolution. These can be utilized to help identify MaP sites and populations in the Atlantic area. In addition, some species have been characterized genetically and the genetic data can also be utilized to identify and characterize sites. However, genetic data is not universally available and in particular may be absent for peripheral sites. There are many data sources for phenotypic traits, such as data from provenance trials but these have not been assessed for MaP populations. There may not be sufficient legislative capacity for the conservation of MaP populations in comparison to, for example, annex habitats of the EU Habitats Directive. Although some of the MaP sites lie within Natura 2000 boundaries, many are not in protected areas. If MaP populations are not characterized and conserved there is a risk of losing traits that may be of potential in adaptation to climate change. A detailed spatial analysis incorporating all of the data is needed to give a comprehensive assessment of the potential threats to MaP populations in this area.

  5. A review of the evidence for genetic structure of cod ( Gadus morhua ) populations in the NW Atlantic and population affinities of larval cod off Newfoundland and the Gulf of St. Lawrence

    DEFF Research Database (Denmark)

    Ruzzante, D.E.; Taggart, C.T.; Cook, D.

    1999-01-01

    , ecological, and oceanographic information, when assessing the genetic structure of highly abundant, widely distributed, and high gene-flow marine fish species. We highlight the role that oceanographic features (e.g., gyre-like systems) and known spatio-temporal differences in spawning time may play...... fish species. (C) 1999 Elsevier Science B.V. All rights reserved...

  6. Feeding opportunities of larval and juvenile cod (Gadus morhua) in a Greenlandic fjord: temporal and spatial linkages between cod and their preferred prey

    DEFF Research Database (Denmark)

    Swalethorp, Rasmus; Kjellerup, Sanne; Malanski, Evandro

    2014-01-01

    preferences of the early-life stages of Atlantic cod (Gadus morhua) to quantify the availability of prey during a spring-summer season in a West Greenlandic fjord. We hypothesized that abundances of larval and juvenile cod at size were synchronized to optimal availability of preferred prey in space and time....... These findings stress the importance of focusing on abundance of preferred prey when assessing the actual prey availability to young fish. We found a spatio-temporal overlap between cod and their preferred prey, and observations suggest that advection of both zooplankton and cod contributed to this overlap...

  7. Hazard Analysis and identification of Critical Control Points of collagen extraction from cod by-products

    NARCIS (Netherlands)

    Aalberts, C.H.J.

    2004-01-01

    The aim of the European research project “UTILISATION AND STABILISATION OF BY-PRODUCTS FROM COD SPECIES” (QLK1-CT-2000-01017 QLRT-2001-02829) is to investigate whether collagen from fish by-products could serve as an important raw material in high quality food. Since Atlantic cod is a major

  8. Satellite monitoring temperature conditions spawning area of the Northeast Arctic cod in the Norwegian Sea and assessment its abundance

    Science.gov (United States)

    Vanyushin, George; Bulatova, Tatiana; Klochkov, Dmitriy; Troshkov, Anatoliy; Kruzhalov, Michail

    2013-04-01

    In this study, the attempt to consider the relationship between sea surface anomalies of temperature (SST anomalies °C) in spawning area of the Norwegian Arctic cod off the Lofoten islands in coastal zone of the Norwegian Sea and modern cod total stock biomass including forecasting assessment of future cod generation success. Continuous long-term database of the sea surface temperature (SST) was created on the NOAA satellites data. Mean monthly SST and SST anomalies are computed for the selected area on the basis of the weekly SST maps for the period of 1998-2012. These maps were plotted with the satellite SST data, as well as information of vessels, byoies and coastal stations. All data were classified by spawning seasons (March-April) and years. The results indicate that poor and low middle generations of cod (2001, 2006, 2007) occurred in years with negative or extremely high positive anomalies in the spawning area. The SST anomalies in years which were close to normal or some more normal significances provide conditions for appearance strong or very strong generations of cod (1998, 2000, 2002, 2004, 2005, 2006, 2008, 2009). Temperature conditions in concrete years influence on different indexes of cod directly. So, the mean temperature in spawning seasons in years 1999-2005 was ≈5,0°C and SST anomaly - +0,35°C, by the way average year significances indexes of cod were: total stock biomass - 1425,0 th.t., total spawning biomass - 460,0 th.t., recruitment (age 3+) - 535,0 mln. units and landings - 530,0 th.t. In spawning seasons 2006-2012 years the average data were following: mean SST ≈6,0°C, SST anomaly - +1,29°C, total stock biomass - 2185,0 th.t., total spawning biomass - 1211,0 th.t., recruitment (age 3+) - 821,0 mln. units and landings - 600,0 th.t. The SST and SST anomalies (the NOAA satellite data) characterize increase of decrease in input of warm Atlantic waters which form numerous eddies along the flows of the main warm currents thus creating

  9. Genetic diversity of populations of the dioecious Myrsine coriacea (Primulaceae in the Atlantic Forest

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    Roberta Pena da Paschoa

    2018-04-01

    Full Text Available ABSTRACT Although a species’ sexual system may influence the genetic diversity of its populations in their natural environment, there have been few such studies involving indigenous species of the Atlantic Forest. Here we study Myrsine coriacea, a dioecious tree widely used in reforestation programs despite a lack of information about its natural interpopulation genetic variation. To address this knowledge gap, intra- and interpopulation genetic diversity were measured for male and female individuals of ten natural populations using ISSR markers. Greater intrapopulation genetic diversity indicated interpopulation gene flow, regardless of isolation and distance between populations. Multivariate analyses detected significant differences in genetic diversity between populations, but not between males and females, which indicates that genetic diversity did not differ between the two sex morphs. Distance between populations was unrelated to genetic diversity. Myrsine coriacea has not experienced a loss of genetic variability despite the characteristic segregated spatial distribution of its populations. These results suggest that obligatory cross-pollination and dispersal by birds may be important mechanisms for the maintenance of genetic diversity in natural populations of M. coriacea.

  10. Regime shifts, resilience and recovery of a cod stock

    DEFF Research Database (Denmark)

    Lindegren, Martin; Diekmann, Rabea; Möllmann, Christian

    2010-01-01

    In the North and Baltic seas Atlantic cod Gadus morhua stocks collapsed as part or one of the major factors inducing large-scale ecosystem regime shifts. Determining the relative contribution of overfishing and climate variability in causing these shifts has proven difficult. While facing similar...

  11. Comparative morphometrics of two populations of Mugil curema (Pisces: Mugilidae on the Atlantic and Mexican Pacific coasts

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    Ana Laura Ibáñez-Aguirre

    2006-03-01

    Full Text Available A population of Mugil curema in the Gulf of Mexico was compared with one in the Pacific Ocean using nine morphometric variables. The allometries of each measurement were estimated in relation to total length. Morphometric variations were analyzed using the normalization of the individuals of each group and two multivariate methods: correspondence analysis, used to explore the information, and discriminant analysis. Results indicated that the diameter of the eye differentiated the populations of both coasts, the Atlantic population showed a larger eye diameter. However, other than this and the body width (which can be strongly influenced by sexual maturation there was no difference between the shapes of both populations. We discuss the larger morphometric variability of the Atlantic population which may be due to the presence of more than one population unlike the Pacific population.

  12. Small mammal populations of an agroecosystem in the Atlantic Forest domain, southeastern Brazil

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    PS. D’Andrea

    Full Text Available This study reports 2 years of the population dynamics and reproduction of a small mammal community using the removal method. The study was conducted in a rural area of the Atlantic Forest, in Sumidouro, Rio de Janeiro State, Brazil. The population sizes, age structure and reproduction were studied for the four most common species in the study area. The overall diversity was 1.67 and ranged between 0.8 to 1.67. The species richness was 13 considering the whole study. The most abundant species were the rodents Nectomys squamipes (n = 133, Akodon cursor (n = 74, Oligoryzomys nigripes (n = 25 and the marsupials Didelphis aurita (n = 58 and Philander frenatus (n = 50. Seven other rodents were captured once: Necromys lasiurus, Akodon montensis, Sooretamys angouya, Oecomys catherine, Oxymycterus judex, Euryzygomatomys spinosus and Trinomys iheringi. There were higher peaks for diversity and species richness during the winter (dry months, probably due to higher food availability. The marsupials had a seasonal reproduction with highest population sizes at the end of the rainy seasons. Nectomys squamipes reproduced mostly during rainy periods. Akodon cursor reproduced predominantly in the winter with the highest population peaks occurring during this season. The analysis of the population dynamics of the rodent species indicated that no species behaved as an agricultural pest, probably due to the heterogeneous landscape of high rotativity of vegetable cultivation. Rodent populations were more susceptible to the removal procedure than marsupial ones.

  13. Cod reproductive ecology

    DEFF Research Database (Denmark)

    Røjbek, Maria

    In recent decades, Baltic cod has experienced a period of low recruitment. In the same period the pelagic Baltic Sea ecosystem experienced a regime shift, due to hydrographic changes, affecting all trophic levels. The rationale for the thesis is built on the hypothesis that the regime shift has r...

  14. Latitudinal Gradient in Otolith Shape among Local Populations of Atlantic Herring (Clupea harengus L.) in Norway.

    Science.gov (United States)

    Libungan, Lísa Anne; Slotte, Aril; Husebø, Åse; Godiksen, Jane A; Pálsson, Snæbjörn

    2015-01-01

    Otolith shape analysis of Atlantic herring (Clupea harengus) in Norwegian waters shows significant differentiation among fjords and a latitudinal gradient along the coast where neighbouring populations are more similar to each other than to those sampled at larger distances. The otolith shape was obtained using quantitative shape analysis, the outlines were transformed with Wavelet and analysed with multivariate methods. The observed morphological differences are likely to reflect environmental differences but indicate low dispersal among the local herring populations. Otolith shape variation suggests also limited exchange between the local populations and their oceanic counterparts, which could be due to differences in spawning behaviour. Herring from the most northerly location (69°N) in Balsfjord, which is genetically more similar to Pacific herring (Clupea pallasii), differed in otolith shape from all the other populations. Our results suggest that the semi-enclosed systems, where the local populations live and breed, are efficient barriers for dispersal. Otolith shape can thus serve as a marker to identify the origin of herring along the coast of Norway.

  15. First record of intestinal parasites in a wild population of jaguar in the Brazilian Atlantic Forest

    Directory of Open Access Journals (Sweden)

    Ana Carolina Srbek-Araujo

    Full Text Available Small and isolated wildlife populations may be more susceptible to disease, which makes illness an important issue to investigate regarding the conservation of large carnivores. Here, we present the results of the first investigation of intestinal parasites in one of the last remaining populations of jaguars in the Brazilian Atlantic Forest. We studied parasites from fecal samples using three different techniques for parasitological examination: floatation in saturated sodium chloride solution, sedimentation and formalin-ether centrifugation. Intestinal parasites were detected in 70% of the analyzed samples, and seven taxa (mean = 3.7 taxa/sample were identified. All the groups of parasites that were identified have been recorded in previous jaguar studies. However, the records of Class Trematoda and nematodes Trichuridae are the first evidence of these groups of worms in free-ranging jaguars in Brazil. Although our results do not provide conclusive evidence on the health of this jaguar population, given its very small size (approximately 20 animals we stress the need to properly understand the dynamics of disease in this wild population and to evaluate the risk of contracting new diseases from domestic species inhabiting the neighboring areas. These represent imperative actions for the successful conservation of this threatened population of jaguar.

  16. Latitudinal Gradient in Otolith Shape among Local Populations of Atlantic Herring (Clupea harengus L.) in Norway

    Science.gov (United States)

    Libungan, Lísa Anne; Slotte, Aril; Husebø, Åse; Godiksen, Jane A.; Pálsson, Snæbjörn

    2015-01-01

    Otolith shape analysis of Atlantic herring (Clupea harengus) in Norwegian waters shows significant differentiation among fjords and a latitudinal gradient along the coast where neighbouring populations are more similar to each other than to those sampled at larger distances. The otolith shape was obtained using quantitative shape analysis, the outlines were transformed with Wavelet and analysed with multivariate methods. The observed morphological differences are likely to reflect environmental differences but indicate low dispersal among the local herring populations. Otolith shape variation suggests also limited exchange between the local populations and their oceanic counterparts, which could be due to differences in spawning behaviour. Herring from the most northerly location (69°N) in Balsfjord, which is genetically more similar to Pacific herring (Clupea pallasii), differed in otolith shape from all the other populations. Our results suggest that the semi-enclosed systems, where the local populations live and breed, are efficient barriers for dispersal. Otolith shape can thus serve as a marker to identify the origin of herring along the coast of Norway. PMID:26101885

  17. Reproductive and population parameters of spiny dogfish Squalus acanthias in the south-western Atlantic Ocean.

    Science.gov (United States)

    Colonello, J H; Cortés, F; Belleggia, M; Massa, A M

    2016-05-01

    The objective of this study was to estimate reproductive and population parameters of the spiny dogfish Squalus acanthias for the south-western Atlantic Ocean. In total, 2714 specimens (1616 males and 1098 females) were collected from surveys carried out using research vessels. Males ranged from 225 to 861 mm total length (LT ) and females from 235 to 925 mm LT . The size at maturity of females (651 mm) was significantly greater than that of males (565 mm). The maximum proportion of mature individuals (Pmax ) of the gestation ogive was 156 mm). The temporal and spatial co-occurrence of non-gravid adult females at different stages of ovarian development, as well as gravid females at all embryonic development stages would indicate that the female reproductive cycle in the south-western Atlantic Ocean is asynchronous. The results indicate that S. acanthias is susceptible to fishing pressure on account of its length at maturity, extended reproductive cycles and low fecundity. © 2016 The Fisheries Society of the British Isles.

  18. Rationale for restocking the Eastern Baltic cod stock

    DEFF Research Database (Denmark)

    Støttrup, Josianne; Overton, Julia Lynne; Paulsen, Helge

    2008-01-01

    The Danish Institute for Fisheries Research and Bornholm's Salmon Hatchery examined the potential for restocking Baltic cod (Gadus morhua callarias L.) in the eastern Baltic Sea. This cod population has adapted to the unique brackish water conditions where successful spawning depends on regular i...

  19. 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.

  20. The between-population genetic architecture of growth, maturation, and plasticity in Atlantic salmon.

    Science.gov (United States)

    Debes, Paul Vincent; Fraser, Dylan John; Yates, Matthew; Hutchings, Jeffrey A

    2014-04-01

    The between-population genetic architecture for growth and maturation has not been examined in detail for many animal species despite its central importance in understanding hybrid fitness. We studied the genetic architecture of population divergence in: (i) maturation probabilities at the same age; (ii) size at age and growth, while accounting for maturity status and sex; and (iii) growth plasticity in response to environmental factors, using divergent wild and domesticated Atlantic salmon (Salmo salar). Our work examined two populations and their multigenerational hybrids in a common experimental arrangement in which salinity and quantity of suspended sediments were manipulated to mimic naturally occurring environmental variation. Average specific growth rates across environments differed among crosses, maturity groups, and cross-by-maturity groups, but a growth-rate reduction in the presence of suspended sediments was equal for all groups. Our results revealed both additive and nonadditive outbreeding effects for size at age and for growth rates that differed with life stage, as well as the presence of different sex- and size-specific maturation probabilities between populations. The major implication of our work is that estimates of the genetic architecture of growth and maturation can be biased if one does not simultaneously account for temporal changes in growth and for different maturation probabilities between populations. Namely, these correlated traits interact differently within each population and between sexes and among generations, due to nonadditive effects and a level of independence in the genetic control for traits. Our results emphasize the challenges to investigating and predicting phenotypic changes resulting from between-population outbreeding.

  1. The hypoxia avoidance behaviour of juvenile Atlantic cod (Gadus morhua L.) depends on the provision and pressure level of an O2 refuge

    DEFF Research Database (Denmark)

    Herbert, Neill A.; Skjaeraasen, Jon E.; Nilsen, Trygve

    2011-01-01

    to a critically low level, i.e. 4.3 kPa-a point where cod can no longer regulate O(2) consumption. Under these conditions, cod did not avoid any level of hypoxia and fish swimming speed also remained unchanged. In contrast, strong avoidance reactions were exhibited in a second experiment when fish were again...... morhua L.) were exposed to a range of O(2) choices in a 2-way choice chamber at 11.4 degrees C over two different experiments. Cod in the first experiment were allowed access to a fixed O(2) refuge (fully air-saturated seawater) whilst oxygen pressure (PO(2)) on the other side was reduced in steps...... exposed to 4.3 kPa but the safety, i.e. PO(2), of the refuge was reduced. Fish not only spent less time at 4.3 kPa as a result of fewer sampling visits but they also swam at considerably slower speeds. The presence of an avoidance response was thus strongly related to refuge PO(2) and it is unlikely...

  2. Population genetic structure of Guiana dolphin (Sotalia guianensis from the southwestern Atlantic coast of Brazil.

    Directory of Open Access Journals (Sweden)

    Juliana Ywasaki Lima

    Full Text Available Sotalia guianensis is a small dolphin that is vulnerable to anthropogenic impacts. Along the Brazilian Atlantic coast, this species is threatened with extinction. A prioritized action plan for conservation strategies relies on increased knowledge of the population. The scarcity of studies about genetic diversity and assessments of population structure for this animal have precluded effective action in the region. Here, we assessed, for the first time, the genetic differentiation at 14 microsatellite loci in 90 S. guianensis specimens stranded on the southeastern Atlantic coast of the State of Espírito Santo, Brazil. We estimated population parameters and structure, measured the significance of global gametic disequilibrium and the intensity of non-random multiallelic interallelic associations and constructed a provisional synteny map using Bos taurus, the closest terrestrial mammal with a reference genome available. All microsatellite loci were polymorphic, with at least three and a maximum of ten alleles each. Allele frequencies ranged from 0.01 to 0.97. Observed heterozygosity ranged from 0.061 to 0.701. The mean inbreeding coefficient was 0.103. Three loci were in Hardy-Weinberg disequilibrium even when missing genotypes were inferred. Although 77 of the 91 possible two-locus associations were in global gametic equilibrium, we unveiled 13 statistically significant, sign-based, non-random multiallelic interallelic associations in 10 two-locus combinations with either coupling (D' values ranging from 0.782 to 0.353 or repulsion (D' values -0.517 to -1.000 forces. Most of the interallelic associations did not involve the major alleles. Thus, for either physically or non-physically linked loci, measuring the intensity of non-random interallelic associations is important for defining the evolutionary forces at equilibrium. We uncovered a small degree of genetic differentiation (FST = 0.010; P-value = 0.463 with a hierarchical clustering into one

  3. Lobster and cod benefit from small-scale northern marine protected areas: inference from an empirical before–after control-impact study

    Science.gov (United States)

    Moland, Even; Olsen, Esben Moland; Knutsen, Halvor; Garrigou, Pauline; Espeland, Sigurd Heiberg; Kleiven, Alf Ring; André, Carl; Knutsen, Jan Atle

    2013-01-01

    Marine protected areas (MPAs) are increasingly implemented as tools to conserve and manage fisheries and target species. Because there are opportunity costs to conservation, there is a need for science-based assessment of MPAs. Here, we present one of the northernmost documentations of MPA effects to date, demonstrated by a replicated before–after control-impact (BACI) approach. In 2006, MPAs were implemented along the Norwegian Skagerrak coast offering complete protection to shellfish and partial protection to fish. By 2010, European lobster (Homarus gammarus) catch-per-unit-effort (CPUE) had increased by 245 per cent in MPAs, whereas CPUE in control areas had increased by 87 per cent. Mean size of lobsters increased by 13 per cent in MPAs, whereas increase in control areas was negligible. Furthermore, MPA-responses and population development in control areas varied significantly among regions. This illustrates the importance of a replicated BACI design for reaching robust conclusions and management decisions. Partial protection of Atlantic cod (Gadus morhua) was followed by an increase in population density and body size compared with control areas. By 2010, MPA cod were on average 5 cm longer than in any of the control areas. MPAs can be useful management tools in rebuilding and conserving portions of depleted lobster populations in northern temperate waters, and even for a mobile temperate fish species such as the Atlantic cod. PMID:23303544

  4. Abundance and population structure of Plesionika narval (Fabricius, 1787 in the Northeastern Atlantic

    Directory of Open Access Journals (Sweden)

    R. Sousa

    2018-04-01

    Full Text Available Abstract Analysis of abundance and population structure of Plesionika narval was performed on data concerning 5,255 specimens obtained from 62 fishing sets carried out off the Madeira archipelago (Northeastern Atlantic between 2004 and 2008 in a depth range from 101 to 350 m. Abundance ranged from 0.01 to 19.74 specimens-per-trap and significant differences were found between seasons, probably as a result of an increment of population in the spring during the recruitment season. The analysis of size distribution revealed that the carapace length (CL ranged from 2.45 to 28.61 mm and that mean female size consistently exceeded that of males. Differences in mean CL were statistically significant between depth strata and seasons. Of the specimens sampled, 57.00% were males, 41.88% females and 1.42% undetermined. Sex ratio also differed significantly between seasons according to depth strata, consolidating the hypothesis of the existence of seasonal migrations related with the reproductive cycle of this species. Ovigerous females showed larger sizes and occurred all year around and remain in shallow waters in winter, summer and autumn and move to deeper waters in spring. The highest frequency of ovigerous females was recorded in summer, between 151 and 200 m deep supporting the hypothesis that spawning of this species occurs in shallow waters, especially in late summer.

  5. Population structure of the burrowing crab Neohelice granulata (Brachyura, Varunidae in a southwestern Atlantic salt marsh

    Directory of Open Access Journals (Sweden)

    Sabrina Angeletti

    2015-07-01

    Full Text Available Neohelice granulata inhabits estuarine and protected coastal areas in temperate regions and is the most dominant decapod crustacean in the Bahía Blanca Estuary, Argentina. The population structure was studied during a year in a SW Atlantic salt marsh located in the Bahía Blanca Estuary. Crabs were sampled monthly from August 2010 to July 2011. The maximum observed density was 30 crabs m-2 in February and 70 burrows m-2 in May. The maximum carapace width (CW was 32 and 27.5 mm in males and females respectively. Medium size crabs were between 16 and 20 mm CW. Significantly smaller sized crabs were observed at the lower intertidal regions (P < 0.05. The sex ratio was favorable for males and was significantly different from the expected 1:1 (P < 0.05. The recruitment of unsexed juveniles crabs (CW <6.5 mm was observed throughout the year and the presence of ovigerous females from October to February indicated seasonal reproduction. The average size of ovigerous females was CW = 20.8 mm and the smallest ovigerous female measured was 16 mm CW. For the first time, the population structure of the most important macro-invertebrate is analyzed in the Bahía Blanca Estuary. This study may help to make decisions in the area, where anthropic action is progressing day by day.

  6. Patterns of genetic diversity of the cryptogenic red alga Polysiphonia morrowii (Ceramiales, Rhodophyta) suggest multiple origins of the Atlantic populations.

    Science.gov (United States)

    Geoffroy, Alexandre; Destombe, Christophe; Kim, Byeongseok; Mauger, Stéphane; Raffo, María Paula; Kim, Myung Sook; Le Gall, Line

    2016-08-01

    The red alga Polysiphonia morrowii, native to the North Pacific (Northeast Asia), has recently been reported worldwide. To determine the origin of the French and Argentine populations of this introduced species, we compared samples from these two areas with samples collected in Korea and at Hakodate, Japan, the type locality of the species. Combined analyses of chloroplastic (rbcL) and mitochondrial (cox1) DNA revealed that the French and Argentine populations are closely related and differ substantially from the Korean and Japanese populations. The genetic structure of P. morrowii populations from South Atlantic and North Atlantic, which showed high haplotype diversity compared with populations from the North Pacific, suggested the occurrence of multiple introduction events from areas outside of the so-called native regions. Although similar, the French and Argentine populations are not genetically identical. Thus, the genetic structure of these two introduced areas may have been modified by cryptic and recurrent introduction events directly from Asia or from other introduced areas that act as introduction relays. In addition, the large number of private cytoplasmic types identified in the two introduced regions strongly suggests that local populations of P. morrowii existed before the recent detection of these invasions. Our results suggest that the most likely scenario is that the source population(s) of the French and Argentine populations was not located only in the North Pacific and/or that P. morrowii is a cryptogenic species.

  7. Observations of volatile organic compounds over the North Atlantic Ocean: relationships to dominant cyanobacterial populations.

    Science.gov (United States)

    Swarthout, R.; Rossell, R.; Sive, B. C.; Zhou, Y.; Reddy, C. M.; Valentine, D. L.; Cox, D.

    2017-12-01

    Marine cyanobacteria are abundant primary producers that can have a major influence on the oceanic biogeochemical cycles. In particular, the prominent cyanobacterial genera Prochlorococcus, Synechococcus, and Trichodesmium can impact the air-sea flux of volatile organic compounds (VOCs) including reactive compounds, such as isoprene, that control the oxidative capacity of the atmosphere and climate-relevant compounds, such as dimethyl sulfide. These groups of cyanobacteria have been estimated to increase in abundance by up to 29% by the end of the century as a result of rising sea surface temperatures and dissolved carbon dioxide concentrations. Given their current and predicted future abundance, understanding the role of different cyanobacterial populations on VOC emissions from the ocean is critical in understanding the future oxidative capacity of the remote atmosphere and climate feedback cycles. During the May 2017 Phosphorus, Hydrocarbons, and Transcriptomics cruise aboard the R/V Neil Armstrong, 160 whole air canister samples were collected along a transect through the North Atlantic from Woods Hole, MA to Bermuda and back with 24-hour stops at nine stations encompassing different nutrient regimes and cyanobacterial populations. At each station, a diurnal time series of samples was collected and higher frequency sampling was conducted during transits of the north wall. Canister samples were analyzed on a five-detector gas chromatography system for over 80 individual VOCs including biogenics, aromatics, chlorinated and brominated compounds, and sulfur containing compounds. Trends in reactive and climate-relevant VOCs will be discussed as a function of the predominant cyanobacterial populations at each sample location. These data provide increased information on the spatial and diurnal variability of trace gases associated with these globally important photosynthetic cyanobacteria.

  8. Human population and socioeconomic modulators of conservation performance in 788 Amazonian and Atlantic Forest reserves.

    Science.gov (United States)

    de Marques, Ana Alice B; Schneider, Mauricio; Peres, Carlos A

    2016-01-01

    Protected areas form a quintessential component of the global strategy to perpetuate tropical biodiversity within relatively undisturbed wildlands, but they are becoming increasingly isolated by rapid agricultural encroachment. Here we consider a network of 788 forest protected areas (PAs) in the world's largest tropical country to examine the degree to which they remain intact, and their responses to multiple biophysical and socioeconomic variables potentially affecting natural habitat loss under varying contexts of rural development. PAs within the complex Brazilian National System of Conservation Units (SNUC) are broken down into two main classes-strictly protected and sustainable use. Collectively, these account for 22.6% of the forest biomes within Brazil's national territory, primarily within the Amazon and the Atlantic Forest, but are widely variable in size, ecoregional representation, management strategy, and the degree to which they are threatened by human activities both within and outside reserve boundaries. In particular, we examine the variation in habitat conversion rates in both strictly protected and sustainable use reserves as a function of the internal and external human population density, and levels of land-use revenue in adjacent human-dominated landscapes. Our results show that PAs surrounded by heavily settled agro-pastoral landscapes face much greater challenges in retaining their natural vegetation, and that strictly protected areas are considerably less degraded than sustainable use reserves, which can rival levels of habitat degradation within adjacent 10-km buffer areas outside.

  9. Human population and socioeconomic modulators of conservation performance in 788 Amazonian and Atlantic Forest reserves

    Directory of Open Access Journals (Sweden)

    Ana Alice B. de Marques

    2016-07-01

    Full Text Available Protected areas form a quintessential component of the global strategy to perpetuate tropical biodiversity within relatively undisturbed wildlands, but they are becoming increasingly isolated by rapid agricultural encroachment. Here we consider a network of 788 forest protected areas (PAs in the world’s largest tropical country to examine the degree to which they remain intact, and their responses to multiple biophysical and socioeconomic variables potentially affecting natural habitat loss under varying contexts of rural development. PAs within the complex Brazilian National System of Conservation Units (SNUC are broken down into two main classes—strictly protected and sustainable use. Collectively, these account for 22.6% of the forest biomes within Brazil’s national territory, primarily within the Amazon and the Atlantic Forest, but are widely variable in size, ecoregional representation, management strategy, and the degree to which they are threatened by human activities both within and outside reserve boundaries. In particular, we examine the variation in habitat conversion rates in both strictly protected and sustainable use reserves as a function of the internal and external human population density, and levels of land-use revenue in adjacent human-dominated landscapes. Our results show that PAs surrounded by heavily settled agro-pastoral landscapes face much greater challenges in retaining their natural vegetation, and that strictly protected areas are considerably less degraded than sustainable use reserves, which can rival levels of habitat degradation within adjacent 10-km buffer areas outside.

  10. Morphometry, growth and reproduction of an Atlantic population of the razor clam Ensis macha (Molina, 1782

    Directory of Open Access Journals (Sweden)

    Pedro J. Barón

    2004-06-01

    Full Text Available Ensis macha is a razor clam distributed throughout the coasts of southern Argentina and Chile. Even though it represents a valuable fishery resource, the exploitation of its Atlantic populations has begun only in recent years. This study provides the first estimates of growth rate, an interpretation of the reproductive cycle on the coast of the northern Argentine Patagonia and an analysis of the species morphometry. Growth was estimated by direct observation of growth rings on the valves by two observers. The reproductive cycle was interpreted by the analysis of temporal change of oocyte size frequency distributions. Parameter estimations for the von Bertalanffy equations respectively obtained by observers 1 and 2 were 154 and 153.7 mm for L?, 0.25 and 0.20 yr-1 for k, and -0.08 and -0.72 yr for t0. Two spawning peaks were detected: September-November 1999 and May-June 2000. However, mature females were found all year round. An abrupt change in the relationship between shell length and height was detected at 11.2 mm length.

  11. Human population and socioeconomic modulators of conservation performance in 788 Amazonian and Atlantic Forest reserves

    Science.gov (United States)

    Schneider, Mauricio; Peres, Carlos A.

    2016-01-01

    Protected areas form a quintessential component of the global strategy to perpetuate tropical biodiversity within relatively undisturbed wildlands, but they are becoming increasingly isolated by rapid agricultural encroachment. Here we consider a network of 788 forest protected areas (PAs) in the world’s largest tropical country to examine the degree to which they remain intact, and their responses to multiple biophysical and socioeconomic variables potentially affecting natural habitat loss under varying contexts of rural development. PAs within the complex Brazilian National System of Conservation Units (SNUC) are broken down into two main classes—strictly protected and sustainable use. Collectively, these account for 22.6% of the forest biomes within Brazil’s national territory, primarily within the Amazon and the Atlantic Forest, but are widely variable in size, ecoregional representation, management strategy, and the degree to which they are threatened by human activities both within and outside reserve boundaries. In particular, we examine the variation in habitat conversion rates in both strictly protected and sustainable use reserves as a function of the internal and external human population density, and levels of land-use revenue in adjacent human-dominated landscapes. Our results show that PAs surrounded by heavily settled agro-pastoral landscapes face much greater challenges in retaining their natural vegetation, and that strictly protected areas are considerably less degraded than sustainable use reserves, which can rival levels of habitat degradation within adjacent 10-km buffer areas outside. PMID:27478703

  12. Seasonal dynamics of Atlantic herring (Clupea harengus L.) populations spawning in the vicinity of marginal habitats.

    Science.gov (United States)

    Eggers, Florian; Slotte, Aril; Libungan, Lísa Anne; Johannessen, Arne; Kvamme, Cecilie; Moland, Even; Olsen, Esben M; Nash, Richard D M

    2014-01-01

    Gillnet sampling and analyses of otolith shape, vertebral count and growth indicated the presence of three putative Atlantic herring (Clupea harengus L.) populations mixing together over the spawning season February-June inside and outside an inland brackish water lake (Landvikvannet) in southern Norway. Peak spawning of oceanic Norwegian spring spawners and coastal Skagerrak spring spawners occurred in March-April with small proportions of spawners entering the lake. In comparison, spawning of Landvik herring peaked in May-June with high proportions found inside the lake, which could be explained by local adaptations to the environmental conditions and seasonal changes of this marginal habitat. The 1.85 km(2) lake was characterized by oxygen depletion occurring between 2.5 and 5 m depth between March and June. This was followed by changes in salinity from 1-7‰ in the 0-1 m surface layer to levels of 20-25‰ deeper than 10 m. In comparison, outside the 3 km long narrow channel connecting the lake with the neighboring fjord, no anoxic conditions were found. Here salinity in the surface layer increased over the season from 10 to 25‰, whereas deeper than 5 m it was stable at around 35‰. Temperature at 0-5 m depth increased significantly over the season in both habitats, from 7 to 14 °C outside and 5 to 17 °C inside the lake. Despite differences in peak spawning and utilization of the lake habitat between the three putative populations, there was an apparent temporal and spatial overlap in spawning stages suggesting potential interbreeding in accordance with the metapopulation concept.

  13. Seasonal dynamics of Atlantic herring (Clupea harengus L. populations spawning in the vicinity of marginal habitats.

    Directory of Open Access Journals (Sweden)

    Florian Eggers

    Full Text Available Gillnet sampling and analyses of otolith shape, vertebral count and growth indicated the presence of three putative Atlantic herring (Clupea harengus L. populations mixing together over the spawning season February-June inside and outside an inland brackish water lake (Landvikvannet in southern Norway. Peak spawning of oceanic Norwegian spring spawners and coastal Skagerrak spring spawners occurred in March-April with small proportions of spawners entering the lake. In comparison, spawning of Landvik herring peaked in May-June with high proportions found inside the lake, which could be explained by local adaptations to the environmental conditions and seasonal changes of this marginal habitat. The 1.85 km(2 lake was characterized by oxygen depletion occurring between 2.5 and 5 m depth between March and June. This was followed by changes in salinity from 1-7‰ in the 0-1 m surface layer to levels of 20-25‰ deeper than 10 m. In comparison, outside the 3 km long narrow channel connecting the lake with the neighboring fjord, no anoxic conditions were found. Here salinity in the surface layer increased over the season from 10 to 25‰, whereas deeper than 5 m it was stable at around 35‰. Temperature at 0-5 m depth increased significantly over the season in both habitats, from 7 to 14 °C outside and 5 to 17 °C inside the lake. Despite differences in peak spawning and utilization of the lake habitat between the three putative populations, there was an apparent temporal and spatial overlap in spawning stages suggesting potential interbreeding in accordance with the metapopulation concept.

  14. Comparison of the Northeast Arctic cod year class strength (at the age of 3+) with the SST anomalies in main spawning ground (the Norwegian Shelf Waters) by results of analysis satellite monitoring data during last years.

    Science.gov (United States)

    Vanyushin, George

    2015-04-01

    Continuous long-term database (1998-2014) on the sea surface temperature (SST) comprising results of regional satellite monitoring (the Norwegian and the Barents seas) is used to resolve several applied problems. Authors have analyzed indirect influence the SST (the NOAA satellite data) on modern cod total stock biomass (abundance of the Northeast Arctic cod at age 3+). In this study, we went on the consideration of the relationship between the SST anomalies for March-April in the main spawning ground of the cod off the Lofoten islands in the Norwegian Shelf Waters and forecasting assessment of future cod generation success and its future abundance of 3 year old. Mean monthly SST and SST anomalies are computed for the selected area on the basis of the weekly SST maps which made by using the NOAA satellites data for the period 1998-2014. Comparison of the SST anomalies in the main spawning ground with abundance of the cod year class at age 3+ shows that survival of the cod generations was inhibited on the whole as negative (below -0,1C) well as positive SST anomalies (above +1,3C) during March and April. Finally, the results indicate that poor and low middle generations of cod at age 3+ (2002, 2004, 2010) occurred in years with negative or extremely high positive the SST anomalies in the spawning area. The SST anomalies in years which were close to normal significances provide conditions for appearance middle or strong generations of cod (2001-2003, 2005-2009, 2011-2013). So, the SST and SST anomalies (by the NOAA satellite data) characterize of increase in input of warm Atlantic waters which form numerous eddies along the main stream thus creating favorable conditions for spawning and development of the cod larvae and fry and provide them with food stock, finally direct influence on forming total stock biomass of cod and helping its population forecast. Key words: satellite monitoring of SST, the Northeast Arctic cod, spawning ground, forecast of the cod year class

  15. Determination of hematology and plasma chemistry reference intervals for 3 populations of captive Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus).

    Science.gov (United States)

    Matsche, Mark A; Arnold, Jill; Jenkins, Erin; Townsend, Howard; Rosemary, Kevin

    2014-09-01

    The imperiled status of Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus), a large, long-lived, anadromous fish found along the Atlantic coast of North America, has prompted efforts at captive propagation for research and stock enhancement. The purpose of this study was to establish hematology and plasma chemistry reference intervals of captive Atlantic sturgeon maintained under different culture conditions. Blood specimens were collected from a total of 119 fish at 3 hatcheries: Lamar, PA (n = 36, ages 10-14 years); Chalk Point, MD (n = 40, siblings of Lamar); and Horn Point, Cambridge, MD (n = 43, mixed population from Chesapeake Bay). Reference intervals (using robust techniques), median, mean, and standard deviations were determined for WBC, RBC, thrombocytes, PCV, HGB, MCV, MCH, MCHC, and absolute counts for lymphocytes (L), neutrophils (N), monocytes, and eosinophils. Chemistry analytes included concentrations of total proteins, albumin, glucose, urea, calcium, phosphate, sodium, potassium, chloride, and globulins, AST, CK, and LDH activities, and osmolality. Mean concentrations of total proteins, albumin, and glucose were at or below the analytic range. Statistical comparisons showed significant differences among hatcheries for each remaining plasma chemistry analyte and for PCV, RBC, MCHC, MCH, eosinophil and monocyte counts, and N:L ratio throughout all 3 groups. Therefore, reference intervals were calculated separately for each population. Reference intervals for fish maintained under differing conditions should be established per population. © 2014 American Society for Veterinary Clinical Pathology and European Society for Veterinary Clinical Pathology.

  16. Population structure of Atlantic Mackerel inferred from RAD-seq derived SNP markers: effects of sequence clustering parameters and hierarchical SNP selection

    KAUST Repository

    Rodrí guez-Ezpeleta, Naiara; Bradbury, Ian R.; Mendibil, Iñ aki; Á lvarez, Paula; Cotano, Unai; Irigoien, Xabier

    2016-01-01

    : the maximum number of mismatches allowed to merge reads into a locus and the relatedness of the individuals used for genotype calling and SNP selection. Our study resolves the population structure of the Atlantic mackerel, but, most importantly, provides

  17. A nuclear DNA basis for shelf- and bank scale population structure in northwest Atlantic cod ( Gadus morhua ) : Labrador to Georges Bank

    DEFF Research Database (Denmark)

    Ruzzante, D.E.; Taggart, C.T.; Cook, D.

    1998-01-01

    by the associated oceanographic features and processes that conceivably form the template for the evolution of the structure. We suggest that bathymetric and hydrodynamic structure represents a rational starting point for developing hypotheses to examine the processes that lead to the genetic structuring of marine...

  18. Genetic stock identification of Atlantic salmon (Salmo salar populations in the southern part of the European range

    Directory of Open Access Journals (Sweden)

    McGinnity Philip

    2010-04-01

    Full Text Available Abstract Background Anadromous migratory fish species such as Atlantic salmon (Salmo salar have significant economic, cultural and ecological importance, but present a complex case for management and conservation due to the range of their migration. Atlantic salmon exist in rivers across the North Atlantic, returning to their river of birth with a high degree of accuracy; however, despite continuing efforts and improvements in in-river conservation, they are in steep decline across their range. Salmon from rivers across Europe migrate along similar routes, where they have, historically, been subject to commercial netting. This mixed stock exploitation has the potential to devastate weak and declining populations where they are exploited indiscriminately. Despite various tagging and marking studies, the effect of marine exploitation and the marine element of the salmon lifecycle in general, remain the "black-box" of salmon management. In a number of Pacific salmonid species and in several regions within the range of the Atlantic salmon, genetic stock identification and mixed stock analysis have been used successfully to quantify exploitation rates and identify the natal origins of fish outside their home waters - to date this has not been attempted for Atlantic salmon in the south of their European range. Results To facilitate mixed stock analysis (MSA of Atlantic salmon, we have produced a baseline of genetic data for salmon populations originating from the largest rivers from Spain to northern Scotland, a region in which declines have been particularly marked. Using 12 microsatellites, 3,730 individual fish from 57 river catchments have been genotyped. Detailed patterns of population genetic diversity of Atlantic salmon at a sub-continent-wide level have been evaluated, demonstrating the existence of regional genetic signatures. Critically, these appear to be independent of more commonly recognised terrestrial biogeographical and political

  19. Recent Demographic History and Present Fine-Scale Structure in the Northwest Atlantic Leatherback (Dermochelys coriacea) Turtle Population

    Science.gov (United States)

    Molfetti, Érica; Torres Vilaça, Sibelle; Georges, Jean-Yves; Plot, Virginie; Delcroix, Eric; Le Scao, Rozen; Lavergne, Anne; Barrioz, Sébastien; dos Santos, Fabrício Rodrigues; de Thoisy, Benoît

    2013-01-01

    The leatherback turtle Dermochelys coriacea is the most widely distributed sea turtle species in the world. It exhibits complex life traits: female homing and migration, migrations of juveniles and males that remain poorly known, and a strong climatic influence on resources, breeding success and sex-ratio. It is consequently challenging to understand population dynamics. Leatherbacks are critically endangered, yet the group from the Northwest Atlantic is currently considered to be under lower risk than other populations while hosting some of the largest rookeries. Here, we investigated the genetic diversity and the demographic history of contrasted rookeries from this group, namely two large nesting populations in French Guiana, and a smaller one in the French West Indies. We used 10 microsatellite loci, of which four are newly isolated, and mitochondrial DNA sequences of the control region and cytochrome b. Both mitochondrial and nuclear markers revealed that the Northwest Atlantic stock of leatherbacks derives from a single ancestral origin, but show current genetic structuration at the scale of nesting sites, with the maintenance of migrants amongst rookeries. Low nuclear genetic diversities are related to founder effects that followed consequent bottlenecks during the late Pleistocene/Holocene. Most probably in response to climatic oscillations, with a possible influence of early human hunting, female effective population sizes collapsed from 2 million to 200. Evidence of founder effects and high numbers of migrants make it possible to reconsider the population dynamics of the species, formerly considered as a metapopulation model: we propose a more relaxed island model, which we expect to be a key element in the currently observed recovering of populations. Although these Northwest Atlantic rookeries should be considered as a single evolutionary unit, we stress that local conservation efforts remain necessary since each nesting site hosts part of the genetic

  20. Recent divergence, intercontinental dispersal and shared polymorphism are shaping the genetic structure of amphi-Atlantic peatmoss populations.

    Science.gov (United States)

    Szövényi, P; Terracciano, S; Ricca, M; Giordano, S; Shaw, A J

    2008-12-01

    Several lines of evidence suggest that recent long-distance dispersal may have been important in the evolution of intercontinental distribution ranges of bryophytes. However, the absolute rate of intercontinental migration and its relative role in the development of certain distribution ranges is still poorly understood. To this end, the genetic structure of intercontinental populations of six peatmoss species showing an amphi-Atlantic distribution was investigated using microsatellite markers. Methods relying on the coalescent were applied (IM and MIGRATE) to understand the evolution of this distribution pattern in peatmosses. Intercontinental populations of the six peatmoss species were weakly albeit significantly differentiated (average F(ST) = 0.104). This suggests that the North Atlantic Ocean is acting as a barrier to gene flow even in bryophytes adapted to long-range dispersal. The im analysis suggested a relatively recent split of intercontinental populations dating back to the last two glacial periods (9000-289,000 years ago). In contrast to previous hypotheses, analyses indicated that both ongoing migration and ancestral polymorphism are important in explaining the intercontinental genetic similarity of peatmoss populations, but their relative contribution varies with species. Migration rates were significantly asymmetric towards America suggesting differential extinction of genotypes on the two continents or invasion of the American continent by European lineages. These results indicate that low genetic divergence of amphi-Atlantic populations is a general pattern across numerous flowering plants and bryophytes. However, in bryophytes, ongoing intercontinental gene flow and retained shared ancestral polymorphism must both be considered to explain the genetic similarity of intercontinental populations.

  1. Study of the copepods population in the Oum Er Rbia estuary (Atlantic Moroccan coast): tides and reservoir release effects

    International Nuclear Information System (INIS)

    El Khalki, A.; Moncef, M.

    2007-01-01

    Variation of environmental parameters and copepods population were studied in the Oum Er Rbia estuary (Atlantic - Moroccan coast) according to the seasons, ( August 1995 to August 1997), tides and reservoir release events. Environemental variability influences copepods diversity and abundance. Salinity (5 to 20 g l-1) appears as the main controlling factor. Among the 27 copepod species recorded, only three marine species (Oithona helgolandica, Euterpina acutifrons, Acartia clausi) and one freshwater species (Acanthocyclops robustus) are able to maintain significant populations due to their large degree of tolerance to salinity changes. (author)

  2. Molecular assessment of mating strategies in a population of Atlantic spotted dolphins.

    Directory of Open Access Journals (Sweden)

    Michelle L Green

    Full Text Available Similar to other small cetacean species, Atlantic spotted dolphins (Stenella frontalis have been the object of concentrated behavioral study. Although mating and courtship behaviors occur often and the social structure of the population is well-studied, the genetic mating system of the species is unknown. To assess the genetic mating system, we genotyped females and their progeny at ten microsatellite loci. Genotype analysis provided estimates of the minimum number of male sires necessary to account for the allelic diversity observed among the progeny. Using the estimates of male sires, we determined whether females mated with the same or different males during independent estrus events. Using Gerud2.0, a minimum of two males was necessary to account for the genetic variation seen among progeny arrays of all tested females. ML-Relate assigned the most likely relationship between offspring pairs; half or full sibling. Relationship analysis supported the conservative male estimates of Gerud2.0 but in some cases, half or full sibling relationships between offspring could not be fully resolved. Integrating the results from Gerud2.0, ML-Relate with previous observational and paternity data, we constructed two-, three-, and four-male pedigree models for each genotyped female. Because increased genetic diversity of offspring may explain multi-male mating, we assessed the internal genetic relatedness of each offspring's genotype to determine whether parent pairs of offspring were closely related. We found varying levels of internal relatedness ranging from unrelated to closely related (range -0.136-0.321. Because there are several hypothesized explanations for multi-male mating, we assessed our data to determine the most plausible explanation for multi-male mating in our study system. Our study indicated females may benefit from mating with multiple males by passing genes for long-term viability to their young.

  3. Contrasting effects of climate change in continental vs. oceanic environments on population persistence and microevolution of Atlantic salmon.

    Science.gov (United States)

    Piou, Cyril; Prévost, Etienne

    2013-03-01

    Facing climate change (CC), species are prone to multiple modifications in their environment that can lead to extinction, migration or adaptation. Identifying the role and interplay of different potential stressors becomes a key question. Anadromous fishes will be exposed to both river and oceanic habitat changes. For Atlantic salmon, the river water temperature, river flow and oceanic growth conditions appear as three main stressing factors. They could act on population dynamics or as selective forces on life-history pathways. Using an individual-based demo-genetic model, we assessed the effects of these factors (1) to compare risks of extinction resulting from CC in river and ocean, and (2) to assess CC effects on life-history pathways including the evolution of underlying genetic control of phenotypic plasticity. We focused on Atlantic salmon populations from Southern Europe for a time horizon of three decades. We showed that CC in river alone should not lead to extinction of Southern European salmon populations. In contrast, the reduced oceanic growth appeared as a significant threat for population persistence. An increase in river flow amplitude increased the risk of local extinction in synergy with the oceanic effects, but river temperature rise reduced this risk. In terms of life-history modifications, the reduced oceanic growth increased the age of return of individuals through plastic and genetic responses. The river temperature rise increased the proportion of sexually mature parr, but the genetic evolution of the maturation threshold lowered the maturation rate of male parr. This was identified as a case of environmentally driven plastic response that masked an underlying evolutionary response of plasticity going in the opposite direction. We concluded that to counteract oceanic effects, river flow management represented the sole potential force to reduce the extinction probability of Atlantic salmon populations in Southern Europe, although this might

  4. Are life histories of Norwegian fjord herring populations of Pacific ancestry similar to those of Atlantic or Pacific herring?

    Science.gov (United States)

    Mikkelsen, Nina; Pedersen, Torstein; dos Santos Schmidt, Thassya Christina; Falk-Petersen, Inger-Britt; Slotte, Aril

    2018-04-01

    Herring from two unexploited fjord populations, Lake Rossfjord (LRH, n = 100) and Balsfjord (BFH, n = 420) in northern Norway, were sampled in 2014 and 2015. Life history characteristics were analysed and compared to the oceanic Norwegian spring-spawning herring (NSSH), and other Atlantic and Pacific herring stocks. Genetic studies have shown that LRH and BFH are ancestors evolved from Pacific herring that hybridized with Atlantic herring. This study shows that both LRH and BFH mature at a relatively early age, at 2-3 years and ca. 4 years respectively, compared to ca. 5 years for NSSH. The spawning stocks of LRH and BFH consist of small fish and contain relatively few age classes. Both fjord populations have slow growth after sexual maturity; LRH has a very low asymptotic length (L∞ = 19.8 cm), while that of BFH is higher (L∞ of 28.5 cm); both these values being lower than that of NSSH (L∞ of ca. 37 cm). The somatic relative fecundity of LRH is 176.6 oocytes g- 1, while the somatic relative fecundity of recruit and repeat BFH spawners is 152.4 and 183.1 oocytes g- 1, respectively. These estimates are lower than those for NSSH and other Atlantic herring fjord populations, but comparable with other Pacific herring. Due to the smaller body sizes of the spawners in the LRH and BFH populations, absolute fecundity is much lower than in NSSH. The gonadosomatic indices of prespawning fish are similar in LRH and BFH, being slightly higher compared to the NSSH, but lower than values reported for Pacific herring. The natural mortality rates of LRH and BFH (M = 0.64 year- 1 and M = 0.76 year- 1, respectively) are much higher than in NSSH (M = 0.15 year- 1) and most other Atlantic herring populations, except the Lusterfjord herring. However, these high mortality rates are similar to those of several Pacific herring populations. It is concluded that LRH and BFH show low somatic growth and high natural mortality rate. These life history characteristics differ from those of

  5. Combination of genetics and spatial modelling highlights the sensitivity of cod (Gadus morhua) population diversity in the North Sea to distributions of fishing

    DEFF Research Database (Denmark)

    Heath, Michael R.; Culling, Mark A.; Crozier, Walter W.

    2014-01-01

    Conserving genetic diversity in animal populations is important for sustaining their ability to respond to environmental change. However, the “between-population” component of genetic diversity (biocomplexity) is threatened in many exploited populations, particularly marine fish, where harvest ma...

  6. Ecological, morphological and genetic divergence of sympatric North Atlantic killer whale populations

    DEFF Research Database (Denmark)

    Foote, Andrew D; Newton, Jason; Piertney, Stuart B

    2009-01-01

    promoting divergence. Here we use morphological traits, nitrogen stable isotope ratios and tooth wear to characterize two disparate types of North Atlantic killer whale. We find a highly specialist type, which reaches up to 8.5 m in length and a generalist type which reaches up to 6.6 m in length...

  7. Foraminifera Population from South Africa Coast Line (Indian and Atlantic Oceans

    Directory of Open Access Journals (Sweden)

    Engin Meriç

    2014-11-01

    Full Text Available Cape Town is the second-largest city of the Republic of South Africa. Research is conducted in 3 different stations: Maori Bay, which lies in the southwest of Cape Town, and Pyramid Rock and Partridge Points which lies in the False Bay, southeast part of Cape Town. Samples are taken from young sediments at 10.00 and 20.00 m depths, and collected by scuba-diving method. The aim of the study is to investigate the living benthic foraminifera assemblages in the Atlantic Ocean, and to compare these assemblages with the southeastern part of the Atlantic Ocean, the Arabian Sea, Indian Ocean and Western Pacific assemblages. Moreover, the aim of the study is to determine whether there are any benthic foraminifera forms reaching to the Mediterranean from Pacific Ocean, Indian Ocean or Red Sea via Suez Channel.

  8. The threatened Atlantic elkhorn coral, Acropora palmata : population dynamics and their policy implications

    OpenAIRE

    Vardi, Tali

    2011-01-01

    Fossil data from multiple locations indicates that Atlantic elkhorn coral, Acropora palmata, formed shallow reefs throughout the Caribbean Sea since the Pleistocene. Beginning in the 1980s A. palmata has declined to a small fraction of its formerly vast extent throughout the region. In 2006, elkhorn coral was the first coral, along with its sister species, staghorn coral (Acropora cervicornis), to be included on the U.S. Endangered Species List. We used size-based matrix mod...

  9. Could seals prevent cod recovery in the Baltic Sea?

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Eero, Margit; Ojaveer, Henn

    2011-01-01

    Fish populations are increasingly affected by multiple human and natural impacts including exploitation, eutrophication, habitat alteration and climate change. As a result many collapsed populations may have to recover in ecosystems whose structure and functioning differ from those in which...... these goals will also depend on how climate change affects cod recruitment....

  10. Density regulation in Northeast Atlantic fish populations: Density dependence is stronger in recruitment than in somatic growth.

    Science.gov (United States)

    Zimmermann, Fabian; Ricard, Daniel; Heino, Mikko

    2018-05-01

    Population regulation is a central concept in ecology, yet in many cases its presence and the underlying mechanisms are difficult to demonstrate. The current paradigm maintains that marine fish populations are predominantly regulated by density-dependent recruitment. While it is known that density-dependent somatic growth can be present too, its general importance remains unknown and most practical applications neglect it. This study aimed to close this gap by for the first time quantifying and comparing density dependence in growth and recruitment over a large set of fish populations. We fitted density-dependent models to time-series data on population size, recruitment and age-specific weight from commercially exploited fish populations in the Northeast Atlantic Ocean and the Baltic Sea. Data were standardized to enable a direct comparison within and among populations, and estimated parameters were used to quantify the impact of density regulation on population biomass. Statistically significant density dependence in recruitment was detected in a large proportion of populations (70%), whereas for density dependence in somatic growth the prevalence of density dependence depended heavily on the method (26% and 69%). Despite age-dependent variability, the density dependence in recruitment was consistently stronger among age groups and between alternative approaches that use weight-at-age or weight increments to assess growth. Estimates of density-dependent reduction in biomass underlined these results: 97% of populations with statistically significant parameters for growth and recruitment showed a larger impact of density-dependent recruitment on population biomass. The results reaffirm the importance of density-dependent recruitment in marine fishes, yet they also show that density dependence in somatic growth is not uncommon. Furthermore, the results are important from an applied perspective because density dependence in somatic growth affects productivity and

  11. Acoustically Induced Streaming Flows near a Model Cod Otolith and their Potential Implications for Fish Hearing

    Energy Technology Data Exchange (ETDEWEB)

    Kotas, Charlotte W [ORNL; Rogers, Peter [Georgia Institute of Technology; Yoda, Minami [Georgia Institute of Technology

    2011-01-01

    The ears of fishes are remarkable sensors for the small acoustic disturbances associated with underwater sound. For example, each ear of the Atlantic cod (Gadus morhua) has three dense bony bodies (otoliths) surrounded by fluid and tissue, and detects sounds at frequencies from 30 to 500 Hz. Atlantic cod have also been shown to localize sounds. However, how their ears perform these functions is not fully understood. Steady streaming, or time-independent, flows near a 350% scale model Atlantic cod otolith immersed in a viscous fluid were studied to determine if these fluid flows contain acoustically relevant information that could be detected by the ear s sensory hair cells. The otolith was oscillated sinusoidally at various orientations at frequencies of 8 24 Hz, corresponding to an actual frequency range of 280 830 Hz. Phaselocked particle pathline visualizations of the resulting flows give velocity, vorticity, and rate of strain fields over a single plane of this mainly two-dimensional flow. Although the streaming flows contain acoustically relevant information, the displacements due to these flows are likely too small to explain Atlantic cod hearing abilities near threshold. The results, however, may suggest a possible mechanism for detection of ultrasound in some fish species.

  12. Estimating population age structure using otolith morphometrics

    DEFF Research Database (Denmark)

    Doering-Arjes, P.; Cardinale, M.; Mosegaard, Henrik

    2008-01-01

    known-age fish individuals. Here we used known-age Atlantic cod (Gadus morhua) from the Faroe Bank and Faroe Plateau stocks. Cod populations usually show quite large variation in growth rates and otolith shape. We showed that including otolith morphometrics into ageing processes has the potential...... populations. The intercalibration method was successful but generalization from one stock to another remains problematic. The development of an otolith growth model is needed for generalization if an operational method for different populations is required in the future....... to make ageing objective, accurate, and fast. Calibration analysis indicated that a known-age sample from the same population and environment is needed to obtain robust calibration; using a sample from a different stock more than doubles the error rate, even in the case of genetically highly related...

  13. Parasite prevalence, infection intensity and richness in an endangered population, the Atlantic-Gaspésie caribou.

    Science.gov (United States)

    Turgeon, Geneviève; Kutz, Susan J; Lejeune, Manigandan; St-Laurent, Martin-Hugues; Pelletier, Fanie

    2018-04-01

    The Atlantic-Gaspésie caribou ( Rangifer tarandus caribou ) population is a small isolated relict herd considered endangered according to the Canadian Species at Risk Act (SARA). This population has low recruitment and survival rates but the potential role of parasites on individual fitness is unknown. In this context, we explored the parasite status of this population with the aim of 1) assessing the occurrence and intensity of parasite infections and the spatial, temporal and individual variations, 2) quantifying parasite richness and investigating factors such as sex and host body condition that may be associated with this variable and 3) evaluating the effects of parasite infections on survival in the Atlantic-Gaspésie caribou population. We examined fecal samples from 32 animals captured in 2013-2014 for eggs, oocysts and larvae of parasites and detected 7 parasite species: dorsal-spined larvae protostrongylids, presumably Parelaphostrongylus andersoni based on PCR identification of a subset, Nematodirus odocoilei and other unidentified Strongyles, Trichuris sp., Capillaria sp., Moniezia sp. and Eimeria sp. For each caribou, mean parasite species richness was 1.8 ± 1.1 (SD). Sex, body condition, year and capture location did not explain parasite prevalence, intensity of infection or richness except for intensity of infection of Capillaria sp. that was positively influenced by body condition. Parasites did not influence survival although mortality was higher for males than for females. We suggest that the relatively low and common gastrointestinal and protostrongylid parasite infections will not be a short-term threat leading to extinction.

  14. Parasite prevalence, infection intensity and richness in an endangered population, the Atlantic-Gaspésie caribou

    Directory of Open Access Journals (Sweden)

    Geneviève Turgeon

    2018-04-01

    Full Text Available The Atlantic-Gaspésie caribou (Rangifer tarandus caribou population is a small isolated relict herd considered endangered according to the Canadian Species at Risk Act (SARA. This population has low recruitment and survival rates but the potential role of parasites on individual fitness is unknown. In this context, we explored the parasite status of this population with the aim of 1 assessing the occurrence and intensity of parasite infections and the spatial, temporal and individual variations, 2 quantifying parasite richness and investigating factors such as sex and host body condition that may be associated with this variable and 3 evaluating the effects of parasite infections on survival in the Atlantic-Gaspésie caribou population. We examined fecal samples from 32 animals captured in 2013–2014 for eggs, oocysts and larvae of parasites and detected 7 parasite species: dorsal-spined larvae protostrongylids, presumably Parelaphostrongylus andersoni based on PCR identification of a subset, Nematodirus odocoilei and other unidentified Strongyles, Trichuris sp., Capillaria sp., Moniezia sp. and Eimeria sp. For each caribou, mean parasite species richness was 1.8 ± 1.1 (SD. Sex, body condition, year and capture location did not explain parasite prevalence, intensity of infection or richness except for intensity of infection of Capillaria sp. that was positively influenced by body condition. Parasites did not influence survival although mortality was higher for males than for females. We suggest that the relatively low and common gastrointestinal and protostrongylid parasite infections will not be a short-term threat leading to extinction. Keywords: Capillaria, Eimeria, Moniezia, Nematodirinae, Parelaphostrongylus andersoni, Rangifer tarandus

  15. Sand fly population dynamics and cutaneous leishmaniasis among soldiers in an Atlantic forest remnant in northeastern Brazil.

    Science.gov (United States)

    Dantas-Torres, Filipe; Sales, Kamila Gaudêncio da Silva; Miranda, Débora Elienai de Oliveira; da Silva, Fernando José; Figueredo, Luciana Aguiar; de Melo, Fábio Lopes; de Brito, Maria Edileuza Felinto; Andrade, Maria Sandra; Brandão-Filho, Sinval Pinto

    2017-02-01

    Outbreaks of cutaneous leishmaniasis are relatively common among soldiers involved in nocturnal activities in tropical forests. We investigated the population dynamics of sand flies in a military training camp located in a remnant of Atlantic rainforest in northeastern Brazil, where outbreaks of cutaneous leishmaniasis have sporadically been described. From July 2012 to July 2014, light traps were monthly placed in 10 collection sites, being nine sites located near the forest edge and one near a sheep and goat stable. Light traps operated from 5:00 pm to 6:00 am, during four consecutive nights. Leishmania infection in sand flies was assessed using a fast real-time PCR assay. Cases of cutaneous leishmaniasis among soldiers were also investigated. In total, 24,606 sand flies belonging to 25 species were identified. Males (n = 12,683) predominated over females (n = 11,923). Sand flies were present during all months, being more numerous in March (n = 1,691) and April 2013 (n = 3,324). Lutzomyia choti (72.9%) was the most abundant species, followed by Lutzomyia longispina (13.8%), Lutzomyia complexa (5.3%), representing together >90% of the sand flies collected. Forty cases of cutaneous leishmaniasis were recorded among soldiers from January 2012 to December 2014. Leishmania isolates were obtained from eight patients and were all characterized as Leishmania braziliensis. Soldiers and anyone overnighting in Atlantic rainforest remnants should adopt preventative measures such as the use of repellents on bare skin or clothes and insecticide-treated tents.

  16. Distribution of water in fresh cod

    DEFF Research Database (Denmark)

    Andersen, Charlotte Møller; Rinnan, A.

    2002-01-01

    Low-field (1)H nuclear magnetic resonance (NMR) transverse relaxation was used to measure water mobility and distribution of water in fresh cod fillets. The NMR relaxations were analysed with the so-called SLICING method giving uni-exponential profiles from which the transverse relaxation time (T(2......)-values) and the relative sizes of the water populations were calculated. Two water populations with the T(2)-values of 50 and 94 ms were obtained. The shortest relaxation time was primarily found near the head, and water with the longest relaxation time was primarily found near the tail. This variation...... can he explained by the smaller muscle cells and muscle fibers in the tail, which may influence the distributions of water into the different pools. The amount of one of the water populations was correlated to the overall water content with a correlation coefficient of -0.94. (C) 2002 Elsevier Science...

  17. Single nucleotide polymorphisms in native South American Atlantic coast populations of smooth shelled mussels: hybridization with invasive European Mytilus galloprovincialis.

    Science.gov (United States)

    Zbawicka, Małgorzata; Trucco, María I; Wenne, Roman

    2018-02-22

    Throughout the world, harvesting of mussels Mytilus spp. is based on the exploitation of natural populations and aquaculture. Aquaculture activities include transfers of spat and live adult mussels between various geographic locations, which may result in large-scale changes in the world distribution of Mytilus taxa. Mytilus taxa are morphologically similar and difficult to distinguish. In spite of much research on taxonomy, evolution and geographic distribution, the native Mytilus taxa of the Southern Hemisphere are poorly understood. Recently, single nucleotide polymorphisms (SNPs) have been used to clarify the taxonomic status of populations of smooth shelled mussels from the Pacific coast of South America. In this paper, we used a set of SNPs to characterize, for the first time, populations of smooth shelled mussels Mytilus from the Atlantic coast of South America. Mytilus spp. samples were collected from eastern South America. Six reference samples from the Northern Hemisphere were used: Mytilus edulis from USA and Northern Ireland, Mytilus trossulus from Canada, and Mytilus galloprovincialis from Spain and Italy. Two other reference samples from the Southern Hemisphere were included: M. galloprovincialis from New Zealand and Mytilus chilensis from Chile. Fifty-five SNPs were successfully genotyped, of which 51 were polymorphic. Population genetic analyses using the STRUCTURE program revealed the clustering of eight populations from Argentina (Mytilus platensis) and the clustering of the sample from Ushuaia with M. chilensis from Chile. All individuals in the Puerto Madryn (Argentina) sample were identified as M. platensis × M. galloprovincialis F2 (88.89%) hybrids, except one that was classified as Mediterranean M. galloprovincialis. No F1 hybrids were observed. We demonstrate that M. platensis (or Mytilus edulis platensis) and M. chilensis are distinct native taxa in South America, which indicates that the evolutionary histories of Mytilus taxa along the

  18. Mitochondrial DNA evidences reflect an incipient population structure in Atlantic goliath grouper (Epinephelus itajara, Epinephelidae in Brazil

    Directory of Open Access Journals (Sweden)

    Júnio S. Damasceno

    2015-12-01

    Full Text Available The Atlantic goliath grouper is a critically endangered species that inhabits estuarine and reef environments and is threatened primarily by fishing activities and habitat destruction. Despite the urgent need for protection, its genetic conservation status remains unknown. The aim of the present study was to evaluate the gene flow among the populations of the species along the coast of Brazil based on the control region of the mitochondrial DNA. The results indicate low haplotype diversity (0.40-0.86 and very low nucleotide diversity (0.1-0.5%. They also show that the genetic diversity of the species varies considerably along the coast and that this finding may be especially important for the identification of priority areas for its conservation. The population analyses indicate a low but significant degree of genetic structuring (ΦST =0.111, probably due to the occurrence of rare haplotypes at some locations, although the genetic differentiation between sites was not correlated with geographic distance (r=0.0501; p=0.7719, and the shared haplotypes indicate that gene flow occurs among all locations along the Brazilian coast. The results of the pairwise FST indicate a high degree of genetic differentiation between locations. The incipient population structuring detected in the present study is not related systematically to the geological or physical features of the Brazilian coast. The complex interaction of fluctuations in sea level, marine currents, and the reproductive characteristics of the species hampers the identification of the specific role of each of these processes in the gene flow dynamics of the population units of the Atlantic goliath grouper. The low overall levels of genetic diversity, the pairwise FST values and the significant population structuring among groups (ΦCT identified in the present study all reinforce the critically endangered status of the species and are inconsistent with the presence of a single, panmictic

  19. Bathymetric and geographic population structure in the pan-Atlantic deep-sea bivalve Deminucula atacellana (Schenck, 1939).

    Science.gov (United States)

    Zardus, John D; Etter, Ron J; Chase, Michael R; Rex, Michael A; Boyle, Elizabeth E

    2006-03-01

    The deep-sea soft-sediment environment hosts a diverse and highly endemic fauna of uncertain origin. We know little about how this fauna evolved because geographic patterns of genetic variation, the essential information for inferring patterns of population differentiation and speciation are poorly understood. Using formalin-fixed specimens from archival collections, we quantify patterns of genetic variation in the protobranch bivalve Deminucula atacellana, a species widespread throughout the Atlantic Ocean at bathyal and abyssal depths. Samples were taken from 18 localities in the North American, West European and Argentine basins. A hypervariable region of mitochondrial 16S rDNA was amplified by polymerase chain reaction (PCR) and sequenced from 130 individuals revealing 21 haplotypes. Except for several important exceptions, haplotypes are unique to each basin. Overall gene diversity is high (h = 0.73) with pronounced population structure (Phi(ST) = 0.877) and highly significant geographic associations (P < 0.0001). Sequences cluster into four major clades corresponding to differences in geography and depth. Genetic divergence was much greater among populations at different depths within the same basin, than among those at similar depths but separated by thousands of kilometres. Isolation by distance probably explains much of the interbasin variation. Depth-related divergence may reflect historical patterns of colonization or strong environmental selective gradients. Broadly distributed deep-sea organisms can possess highly genetically divergent populations, despite the lack of any morphological divergence.

  20. Cod monitoring; results 2015, quarter 3

    NARCIS (Netherlands)

    Reijden, van der K.J.; Machiels, M.A.M.; Trapman, B.K.; Kraan, M.L.

    2015-01-01

    The Cod monitoring program is part of the Dutch cod avoidance plan developed by the Dutch Government together with the Dutch fishing sector. The aim of this cod monitoring program is to provide information on the Catch per Unit Effort (CpUE) in the TR fleet (bottom trawls and seines). This is needed

  1. Cod monitoring : results 2015, quarter 2

    NARCIS (Netherlands)

    Teal, L.R.; Reijden, van der K.J.; Machiels, M.A.M.; Kraan, M.L.

    2015-01-01

    The Cod monitoring program is part of the Dutch cod avoidance plan developed by the Dutch Government together with the Dutch fishing sector. The aim of this cod monitoring program is to provide information on the Catch per Unit Effort (CpUE) in the TR fleet (bottom trawls and seines). This is needed

  2. Population Genomics Reveals Seahorses (Hippocampus erectus) of the Western Mid-Atlantic Coast to Be Residents Rather than Vagrants

    Science.gov (United States)

    Boehm, J. T.; Waldman, John; Robinson, John D.; Hickerson, Michael J.

    2015-01-01

    Understanding population structure and areas of demographic persistence and transients is critical for effective species management. However, direct observational evidence to address the geographic scale and delineation of ephemeral or persistent populations for many marine fishes is limited. The Lined seahorse (Hippocampus erectus) can be commonly found in three western Atlantic zoogeographic provinces, though inhabitants of the temperate northern Virginia Province are often considered tropical vagrants that only arrive during warm seasons from the southern provinces and perish as temperatures decline. Although genetics can locate regions of historical population persistence and isolation, previous evidence of Virginia Province persistence is only provisional due to limited genetic sampling (i.e., mitochondrial DNA and five nuclear loci). To test alternative hypotheses of historical persistence versus the ephemerality of a northern Virginia Province population we used a RADseq generated dataset consisting of 11,708 single nucleotide polymorphisms (SNP) sampled from individuals collected from the eastern Gulf of Mexico to Long Island, NY. Concordant results from genomic analyses all infer three genetically divergent subpopulations, and strongly support Virginia Province inhabitants as a genetically diverged and a historically persistent ancestral gene pool. These results suggest that individuals that emerge in coastal areas during the warm season can be considered “local” and supports offshore migration during the colder months. This research demonstrates how a large number of genes sampled across a geographical range can capture the diversity of coalescent histories (across loci) while inferring population history. Moreover, these results clearly demonstrate the utility of population genomic data to infer peripheral subpopulation persistence in difficult-to-observe species. PMID:25629166

  3. Population genomics reveals seahorses (Hippocampus erectus of the western mid-Atlantic coast to be residents rather than vagrants.

    Directory of Open Access Journals (Sweden)

    J T Boehm

    Full Text Available Understanding population structure and areas of demographic persistence and transients is critical for effective species management. However, direct observational evidence to address the geographic scale and delineation of ephemeral or persistent populations for many marine fishes is limited. The Lined seahorse (Hippocampus erectus can be commonly found in three western Atlantic zoogeographic provinces, though inhabitants of the temperate northern Virginia Province are often considered tropical vagrants that only arrive during warm seasons from the southern provinces and perish as temperatures decline. Although genetics can locate regions of historical population persistence and isolation, previous evidence of Virginia Province persistence is only provisional due to limited genetic sampling (i.e., mitochondrial DNA and five nuclear loci. To test alternative hypotheses of historical persistence versus the ephemerality of a northern Virginia Province population we used a RADseq generated dataset consisting of 11,708 single nucleotide polymorphisms (SNP sampled from individuals collected from the eastern Gulf of Mexico to Long Island, NY. Concordant results from genomic analyses all infer three genetically divergent subpopulations, and strongly support Virginia Province inhabitants as a genetically diverged and a historically persistent ancestral gene pool. These results suggest that individuals that emerge in coastal areas during the warm season can be considered "local" and supports offshore migration during the colder months. This research demonstrates how a large number of genes sampled across a geographical range can capture the diversity of coalescent histories (across loci while inferring population history. Moreover, these results clearly demonstrate the utility of population genomic data to infer peripheral subpopulation persistence in difficult-to-observe species.

  4. Developing Baltic cod recruitment models I : Resolving spatial and temporal dynamics of spawning stock and recruitment for cod, herring, and sprat

    DEFF Research Database (Denmark)

    Köster, Fritz; Möllmann, C.; Neuenfeldt, Stefan

    2001-01-01

    The Baltic Sea comprises a heterogeneous oceanographic environment influencing the spatial and temporal potential for reproductive success of cod (Gadus morhua) and sprat (Sprattus sprattus) in the different spawning basins. Hence, to quantify stock and recruitment dynamics, it is necessary......-disaggregated multispecies virtual population analyses (MSVPA) were performed for interacting species cod, herring (Clupea harengus), and sprat in the different subdivisions of the Central Baltic. The MSVPA runs revealed distinct spatial trends in population abundance, spawning biomass, recruitment, and predation...

  5. Sand fly population dynamics and cutaneous leishmaniasis among soldiers in an Atlantic forest remnant in northeastern Brazil.

    Directory of Open Access Journals (Sweden)

    Filipe Dantas-Torres

    2017-02-01

    Full Text Available Outbreaks of cutaneous leishmaniasis are relatively common among soldiers involved in nocturnal activities in tropical forests. We investigated the population dynamics of sand flies in a military training camp located in a remnant of Atlantic rainforest in northeastern Brazil, where outbreaks of cutaneous leishmaniasis have sporadically been described. From July 2012 to July 2014, light traps were monthly placed in 10 collection sites, being nine sites located near the forest edge and one near a sheep and goat stable. Light traps operated from 5:00 pm to 6:00 am, during four consecutive nights. Leishmania infection in sand flies was assessed using a fast real-time PCR assay. Cases of cutaneous leishmaniasis among soldiers were also investigated. In total, 24,606 sand flies belonging to 25 species were identified. Males (n = 12,683 predominated over females (n = 11,923. Sand flies were present during all months, being more numerous in March (n = 1,691 and April 2013 (n = 3,324. Lutzomyia choti (72.9% was the most abundant species, followed by Lutzomyia longispina (13.8%, Lutzomyia complexa (5.3%, representing together >90% of the sand flies collected. Forty cases of cutaneous leishmaniasis were recorded among soldiers from January 2012 to December 2014. Leishmania isolates were obtained from eight patients and were all characterized as Leishmania braziliensis. Soldiers and anyone overnighting in Atlantic rainforest remnants should adopt preventative measures such as the use of repellents on bare skin or clothes and insecticide-treated tents.

  6. Comparative biology and population mixing among local, coastal and offshore Atlantic herring (Clupea harengus) in the North Sea, Skagerrak, Kattegat and western Baltic

    Science.gov (United States)

    Slotte, Aril; Johannessen, Arne; Kvamme, Cecilie; Clausen, Lotte Worsøe; Nash, Richard D. M.

    2017-01-01

    The population structure of Atlantic herring (Clupea harengus) from 13 local, coastal and offshore areas of the North Sea, Skagerrak, Kattegat and western Baltic (northeast Atlantic) was studied using biological and environmental data from 1970–2015. The objective was to identify distinct populations by comparing variability in the temporal and spatial phenotypic characteristics and evaluate the potential for mixing of populations in time and space. The populations varied in biological characteristics such as mean vertebral counts (VS), growth and maturity ogives. Generalized additive models indicated temporally stable VS in the North Sea and western Baltic, whereas intra-annual temporal variation of VS occurred in other areas. High variability of VS within a population was not affected by environmental factors such as temperature and salinity. Consequently, seasonal VS variability can be explained by the presence or absence of herring populations as they migrate between areas. The three main populations identified in this paper correspond to the three managed stocks in this area: Norwegian spring spawners (NSS), western Baltic spring spawners (WBSS) and North Sea autumn spawners (NSAS). In addition, several local populations were identified in fjords or lakes along the coast, but our analyses could not detect direct mixing of local populations with the three main populations. Our results highlight the importance of recognizing herring dynamics and understanding the mixing of populations as a challenge for management of herring. PMID:29084258

  7. Connecting Amazonian, Cerrado, and Atlantic Forest histories: Paraphyly, old divergences, and modern population dynamics in tyrant-manakins (Neopelma/Tyranneutes, Aves: Pipridae).

    Science.gov (United States)

    Capurucho, João Marcos Guimarães; Ashley, Mary V; Ribas, Camila C; Bates, John M

    2018-06-11

    Several biogeographic hypotheses have been proposed to explain connections between Amazonian and Atlantic forest biotas. These hypotheses are related to the timing of the connections and their geographic patterns. We performed a phylogeographic investigation of Tyrant-manakins (Aves: Pipridae, Neopelma/Tyranneutes) which include species inhabiting the Amazon and Atlantic forests, as well as gallery forests of the Cerrado. Using DNA sequence data, we determined phylogenetic relationships, temporal and geographic patterns of diversification, and recent intraspecific population genetic patterns, relative to the history of these biomes. We found Neopelma to be a paraphyletic genus, as N. chrysolophum is sister to Neopelma + Tyranneutes, with an estimated divergence of approximately 18 Myrs BP, within the oldest estimated divergence times of other Amazonian and Atlantic forest avian taxa. Subsequent divergences in the group occurred from Mid Miocene to Early Pliocene and involved mainly the Amazonian species, with an expansion into and subsequent speciation in the Cerrado gallery forests by N. pallescens. We found additional structure within N. chrysocephalum and N. sulphureiventer. Analysis of recent population dynamics in N. chrysocephalum, N. sulphureiventer, and N. pallescens revealed recent demographic fluctuations and restrictions to gene flow related to environmental changes since the last glacial cycle. No genetic structure was detected across the Amazon River in N. pallescens. The tyrant-manakins represent an old historical connection between the Amazon and Atlantic Forest. Copyright © 2018. Published by Elsevier Inc.

  8. Population structure and historical demography of the thorny skate (Amblyraja radiata, Rajidae) in the North Atlantic

    NARCIS (Netherlands)

    Chevolot, M.; Wolfs, P.H.J.; Palsson, J.; Rijnsdorp, A.D.; Stam, W.T.; Olsen, J.L.

    2007-01-01

    Population genetic structure of the thorny skate (Amblyraja radiata) was surveyed in >300 individuals sampled from Newfoundland, Iceland, Norway, the Kattegat and the central North Sea. A 290-bp fragment of the mt cytochrome-b gene was first screened by SSCP. Sequences of SSCP haplotypes revealed

  9. Population structure and historical demography of the thorny skate (Amblyraja radiata, Rajidae) in the North Atlantic

    NARCIS (Netherlands)

    Chevolot, Malia; Wolfs, Peter H. J.; Palsson, Jonbjorn; Rijnsdorp, Adriaan D.; Stam, Wytze T.; Olsen, Jeanine L.; Palson, J.

    Population genetic structure of the thorny skate (Amblyraja radiata) was surveyed in > 300 individuals sampled from Newfoundland, Iceland, Norway, the Kattegat and the central North Sea. A 290-bp fragment of the mt cytochrome-b gene was first screened by SSCP. Sequences of SSCP haplotypes revealed

  10. What can otolith shape analysis tell us about population structure of the European sardine, Sardina pilchardus, from Atlantic and Mediterranean waters?

    Science.gov (United States)

    Jemaa, Sharif; Bacha, Mahmoud; Khalaf, Gaby; Dessailly, David; Rabhi, Khalef; Amara, Rachid

    2015-02-01

    The European sardine, Sardina pilchardus, exhibits a complex population structure, which has produced conflicting results in previous genetic studies. Despite its importance in the fisheries industry, stock delineation for management and conservation purposes is still a matter of debate throughout the distribution range of the species. This study examines whether otolith shapes are more efficient than genetic markers to detect population structure in pelagic species with large population sizes. Sardines were analyzed from 15 sampling localities in the Northeast Atlantic and Mediterranean Sea covering almost the whole distribution range of the species. A combination of otolith shape indices and elliptic Fourier descriptors was investigated by multivariate statistical procedures. Within the studied area, three distinct groups were identified with an overall correct classification of 77%. Group A: northern Mediterranean Sea and Gulf of Gabès; group B: Atlantic Morocco-south Alboran-Algero-provençal coasts; and group C: European Atlantic coast. The Almeria-Oran front and the Gibraltar strait are not an efficient barrier for sardine population separation as there seems to be exchanges between populations of the south-western Mediterranean Sea and those of the Moroccan Atlantic Ocean coast or Gulf of Cadiz. The results are discussed in relation to environmental conditions, oceanographic features, and physical barriers to dispersal in the study area, and compared with those obtained by previous genetic, morphometric, and meristic data. For pelagic species with high gene flow, present results highlighted the need to take into account the identification of phenotypic stocks to ensure sustainable fishery benefits and efficient conservation as they may have unique demographic properties and responses to exploitation.

  11. Population structure of Atlantic Mackerel inferred from RAD-seq derived SNP markers: effects of sequence clustering parameters and hierarchical SNP selection

    KAUST Repository

    Rodríguez-Ezpeleta, Naiara

    2016-03-03

    Restriction-site associated DNA sequencing (RAD-seq) and related methods are revolutionizing the field of population genomics in non-model organisms as they allow generating an unprecedented number of single nucleotide polymorphisms (SNPs) even when no genomic information is available. Yet, RAD-seq data analyses rely on assumptions on nature and number of nucleotide variants present in a single locus, the choice of which may lead to an under- or overestimated number of SNPs and/or to incorrectly called genotypes. Using the Atlantic mackerel (Scomber scombrus L.) and a close relative, the Atlantic chub mackerel (Scomber colias), as case study, here we explore the sensitivity of population structure inferences to two crucial aspects in RAD-seq data analysis: the maximum number of mismatches allowed to merge reads into a locus and the relatedness of the individuals used for genotype calling and SNP selection. Our study resolves the population structure of the Atlantic mackerel, but, most importantly, provides insights into the effects of alternative RAD-seq data analysis strategies on population structure inferences that are directly applicable to other species.

  12. Host size-dependent anisakid infection in Baltic cod Gadus morhua associated with differential food preferences

    DEFF Research Database (Denmark)

    Zuo, Shaozhi; Huwer, Bastian; Bahlool, Qusay

    2016-01-01

    A significant increase in the infection level of Baltic cod Gadus morhua with the anisakid nematode larvae Contracaecum osculatum and Pseudoterranova decipiens has been recorded during recent years due to the expanding local population of grey seals Halichoerus grypus, which act as final hosts...... for these parasites. Here, we report from an investigation of 368 cod (total length [TL] 6-49 cm; caught in ICES Subdivision 25) that the infection level of juvenile cod (TL 6-30 cm) with larvae of C. osculatum and P. decipiens is absent or very low, whereas it increases drastically in larger cod (TL 31-48 cm...... suggest that the C. osculatum life cycle in the Baltic Sea includes grey seals as final hosts, sprat as the first transport host and cod as second transport host. It may be speculated that sprat obtain infection by feeding on copepods and/or cladocerans, which could serve as the first intermediate hosts...

  13. Seasonal Variation in Population Abundance and Chytrid Infection in Stream-Dwelling Frogs of the Brazilian Atlantic Forest.

    Directory of Open Access Journals (Sweden)

    Joice Ruggeri

    Full Text Available Enigmatic amphibian declines were first reported in southern and southeastern Brazil in the late 1980s and included several species of stream-dwelling anurans (families Hylodidae and Cycloramphidae. At that time, we were unaware of the amphibian-killing fungus Batrachochytrium dendrobatidis (Bd; therefore, pollution, habitat loss, fragmentation and unusual climatic events were hypothesized as primary causes of these declines. We now know that multiple lineages of Bd have infected amphibians of the Brazilian Atlantic forest for over a century, yet declines have not been associated specifically with Bd outbreaks. Because stream-dwelling anurans occupy an environmental hotspot ideal for disease transmission, we investigated temporal variation in population and infection dynamics of three stream-adapted species (Hylodes asper, H. phyllodes, and Cycloramphus boraceiensis on the northern coast of São Paulo state, Brazil. We surveyed standardized transects along streams for four years, and show that fluctuations in the number of frogs correlate with specific climatic variables that also increase the likelihood of Bd infections. In addition, we found that Bd infection probability in C. boraceiensis, a nocturnal species, was significantly higher than in Hylodes spp., which are diurnal, suggesting that the nocturnal activity may either facilitate Bd zoospore transmission or increase susceptibility of hosts. Our findings indicate that, despite long-term persistence of Bd in Brazil, some hosts persist with seasonally variable infections, and thus future persistence in the face of climate change will depend on the relative effect of those changes on frog recruitment and pathogen proliferation.

  14. Short term effects of particle exposure on hospital admissions in the Mid-Atlantic states: a population estimate.

    Directory of Open Access Journals (Sweden)

    Itai Kloog

    Full Text Available Many studies report significant associations between PM(2.5 (particulate matter <2.5 micrometers and hospital admissions. These studies mostly rely on a limited number of monitors which introduces exposure error, and excludes rural and suburban populations from locations where monitors are not available, reducing generalizability and potentially creating selection bias.Using prediction models developed by our group, daily PM(2.5 exposure was estimated across the Mid-Atlantic (Washington D.C., and the states of Delaware, Maryland, New Jersey, Pennsylvania, Virginia, New York and West Virginia. We then investigated the short-term effects of PM(2.5exposures on emergency hospital admissions of the elderly in the Mid-Atlantic region.We performed case-crossover analysis for each admission type, matching on day of the week, month and year and defined the hazard period as lag01 (a moving average of day of admission exposure and previous day exposure.We observed associations between short-term exposure to PM(2.5 and hospitalization for all outcomes examined. For example, for every 10-µg/m(3 increase in short-term PM(2.5 there was a 2.2% increase in respiratory diseases admissions (95% CI = 1.9 to 2.6, and a 0.78% increase in cardiovascular disease (CVD admission rate (95% CI = 0.5 to 1.0. We found differences in risk for CVD admissions between people living in rural and urban areas. For every10-µg/m(3 increase in PM(2.5 exposure in the 'rural' group there was a 1.0% increase (95% CI = 0.6 to 1.5, while for the 'urban' group the increase was 0.7% (95% CI = 0.4 to 1.0.Our findings showed that PM(2.5 exposure was associated with hospital admissions for all respiratory, cardio vascular disease, stroke, ischemic heart disease and chronic obstructive pulmonary disease admissions. In addition, we demonstrate that our AOD (Aerosol Optical Depth based exposure models can be successfully applied to epidemiological studies investigating the health

  15. Health assessment of wild lowland tapir (Tapirus terrestris) populations in the Atlantic Forest and Pantanal biomes, Brazil (1996-2012).

    Science.gov (United States)

    Medici, Emília Patrícia; Mangini, Paulo Rogerio; Fernandes-Santos, Renata Carolina

    2014-10-01

    Abstract The lowland tapir (Tapirus terrestris) is found in South America and is listed as Vulnerable to Extinction by the International Union for Conservation of Nature, Red List of Threatened Species. Health issues, particularly infectious diseases, are potential threats for the species. Health information from 65 wild tapirs from two Brazilian biomes, Atlantic Forest (AF) and Pantanal (PA), were collected during a long-term study (1996-2012). The study included physic, hematologic and biochemical evaluations, microbiologic cultures, urinalysis, and serologic analyses for antibodies against 13 infectious agents (viral and bacterial). The AF and PA tapirs were significantly different for several hematologic and biochemical parameters. Ten bacteria taxa were identified in the AF and 26 in the PA. Antibodies against five viruses were detected: Bluetongue virus, eastern equine encephalitis virus, western equine encephalitis virus, infectious bovine rhinotracheitis virus, and porcine parvovirus. A high prevalence of exposure to Leptospira interrogans (10 serovars: Autumnalis, Bratislava, Canicola, Copenhageni, Grippotyphosa, Hardjo, Hebdomadis, Icterohaemorrhagiae, Pomona, and Pyrogenes) was detected in both the AF and PA sites. A greater diversity of serovars and higher antibody titers were found in the PA. Statistically significant differences between sites were found for L. interrogans, equine encephalitis virus, and porcine parvovirus. Based on physical evaluations, both AF and PA populations were healthy. The differences in the overall health profile of the AF and PA tapir populations appear to be associated with environmental factors and infectious diseases ecology. The extensive datasets on hematology, biochemistry, urinalysis, and microbiology results from this paper can be used as reference values for wild tapirs.

  16. New species in the genus Francisella (Gammaproteobacteria; Francisellaceae); Francisella piscicida sp. nov. isolated from cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Ottem, Karl F; Nylund, Are; Karlsbakk, Egil

    2007-01-01

    A Francisella strain, GM2212, previously isolated from moribund farmed Atlantic cod (Gadus morhua) in Norway, is closely related to Francisella philomiragia among Francisella spp. according to its complete 16S rDNA, 16S-23S intergenic spacer, 23S rDNA, 23S-5S intergenic spacer, 5S rDNA, Fop...

  17. Calcium from salmon and cod bone is well absorbed in young healthy men: a double-blinded randomised crossover design

    Directory of Open Access Journals (Sweden)

    Graff Ingvild E

    2010-07-01

    Full Text Available Abstract Background Calcium (Ca - fortified foods are likely to play an important role in helping the consumer achieve an adequate Ca intake, especially for persons with a low intake of dairy products. Fish bones have a high Ca content, and huge quantities of this raw material are available as a by-product from the fish industry. Previously, emphasis has been on producing high quality products from fish by-products by use of bacterial proteases. However, documentation of the nutritional value of the enzymatically rinsed Ca-rich bone fraction remains unexplored. The objective of the present study was to assess the bioavailability of calcium in bones of Atlantic salmon (oily fish and Atlantic cod (lean fish in a double-blinded randomised crossover design. Methods Ca absorption was measured in 10 healthy young men using 47Ca whole body counting after ingestion of a test meal extrinsically labelled with the 47Ca isotope. The three test meals contained 800 mg of Ca from three different calcium sources: cod bones, salmon bones and control (CaCO3. Results Mean Ca absorption (± SEE from the three different Ca sources were 21.9 ± 1.7%, 22.5 ± 1.7% and 27.4 ± 1.8% for cod bones, salmon bones, and control (CaCO3, respectively. Conclusion We conclude that bones from Atlantic salmon and Atlantic cod are suitable as natural Ca sources in e.g. functional foods or as supplements.

  18. Calcium from salmon and cod bone is well absorbed in young healthy men: a double-blinded randomised crossover design.

    Science.gov (United States)

    Malde, Marian K; Bügel, Susanne; Kristensen, Mette; Malde, Ketil; Graff, Ingvild E; Pedersen, Jan I

    2010-07-20

    Calcium (Ca) - fortified foods are likely to play an important role in helping the consumer achieve an adequate Ca intake, especially for persons with a low intake of dairy products. Fish bones have a high Ca content, and huge quantities of this raw material are available as a by-product from the fish industry. Previously, emphasis has been on producing high quality products from fish by-products by use of bacterial proteases. However, documentation of the nutritional value of the enzymatically rinsed Ca-rich bone fraction remains unexplored. The objective of the present study was to assess the bioavailability of calcium in bones of Atlantic salmon (oily fish) and Atlantic cod (lean fish) in a double-blinded randomised crossover design. Ca absorption was measured in 10 healthy young men using 47Ca whole body counting after ingestion of a test meal extrinsically labelled with the 47Ca isotope. The three test meals contained 800 mg of Ca from three different calcium sources: cod bones, salmon bones and control (CaCO3). Mean Ca absorption (+/- SEE) from the three different Ca sources were 21.9 +/- 1.7%, 22.5 +/- 1.7% and 27.4 +/- 1.8% for cod bones, salmon bones, and control (CaCO3), respectively. We conclude that bones from Atlantic salmon and Atlantic cod are suitable as natural Ca sources in e.g. functional foods or as supplements.

  19. Characterization of natural variation in North American Atlantic Salmon populations (Salmonidae: Salmo salar) at a locus with a major effect on sea age.

    Science.gov (United States)

    Kusche, Henrik; Côté, Guillaume; Hernandez, Cécilia; Normandeau, Eric; Boivin-Delisle, Damien; Bernatchez, Louis

    2017-08-01

    Age at maturity is a key life-history trait of most organisms. In anadromous salmonid fishes such as Atlantic Salmon ( Salmo salar ), age at sexual maturity is associated with sea age, the number of years spent at sea before the spawning migration. For the first time, we investigated the presence of two nonsynonymous vgll3 polymorphisms in North American Atlantic Salmon populations that relate to sea age in European salmon and quantified the natural variation at these and two additional candidate SNPs from two other genes. A targeted resequencing assay was developed and 1,505 returning adult individuals of size-inferred sea age and sex from four populations were genotyped. Across three of four populations sampled in Québec, Canada, the late-maturing component (MSW) of the population of a given sex exhibited higher proportions of SNP genotypes 54Thr vgll3 and 323Lys vgll3 compared to early-maturing fish (1SW), for example, 85% versus 53% of females from Trinité River carried 323Lys vgll3 ( n MSW  = 205 vs. n 1SW  = 30; p 66%) to be female. In summary, two nonsynonymous vgll3 polymorphisms were confirmed in North American populations of Atlantic Salmon and our results suggest that variation at those loci correlates with sea age and sex. Our results also suggest that this correlation varies among populations. Future work would benefit from a more balanced sampling and from adding data on juvenile riverine life stages to contrast our data.

  20. Diet of Norwegian coastal cod (Gadus morhua) studied by using citizen science

    Science.gov (United States)

    Enoksen, Siri Elise; Reiss, Henning

    2018-04-01

    The Norwegian coastal cod (Gadus morhua) is a keystone species in the food web of northern Norwegian fjords. Their relatively stationary populations might specifically depend on local food resources, but the diet of cod has rarely been studied in fjord systems. Using a citizen science approach, where recreational anglers and tourists participated in the sampling, we studied small-scale differences in the diet composition of cod in a fjord system in northern Norway. We compared the cod diet from the MPA Saltstraumen, characterised by strong tidal currents and a highly diverse and abundant fauna, with the inner fjord area of Skjerstadfjord. The diet composition of cod significantly differed between both areas within the fjord. Although fish was the dominant prey in both areas, cod consumed > 40% invertebrates in terms of weight, even in the cod size class of 70-99 cm. The invertebrate prey also caused the observed spatial differences. In Saltstraumen, brittle stars (Ophiuroidea), crabs (Brachyura) and sea cucumbers (Holothuroidea) were important food sources for cod, while sea urchins (Echinoidea), clams (Bivalvia), shrimps (Caridea) and krill (Euphausiacea) dominated the diet in the inner Skjerstadfjord. The high densities of sessile fauna in the dynamic environment of Saltstraumen, was only partly reflected in the diet of cod, with only Holothuroidea found in 17% of the stomachs. High rates of empty stomachs (24%), cannibalism as well as a higher proportion of low-energy prey in the diet of large cod, may indicate a shortage of high quality food in Skjerstadfjord. The samples for this study were collected through a citizen science campaign. This approach might provide opportunities to be used for coastal ecological monitoring with potential applications in local ecosystem management strategies through public involvement.

  1. Ten-year variations in population structure of pink-shrimp in a southwestern Atlantic Bay affected by highway construction

    Directory of Open Access Journals (Sweden)

    Felipe Freitas Jr

    2011-12-01

    Full Text Available OBJECTIVES: Population structures of Farfantepenaeus brasiliensis and F. paulensis, consisting mainly of juveniles, were evaluated during the construction of an expressway along a mangrove area. Estuarine regions in southern Brazil function as sites for reproduction, nursery and growth of a variety of organisms, including two of the most important species of shrimp for fisheries in the southwestern Atlantic. Shrimps were collected in Saco dos Limões creek, Baía-Sul, Florianópolis, State of Santa Catarina, four times a year, by day and night, between 1997 and 2006. Fluctuations in the abundances of shrimp appear to be related to their life cycles, with largest abundances in Summer and Spring, rather than to impacts promoted by dredging activities during the expressway construction.OBJETIVOS: A estrutura populacional de Farfantepenaeus brasiliensis e F. paulensis, consistindo principalmente de juvenis, foi avaliada durante a construção de uma via expressa ao longo de uma área de manguezais. Regiões estuarinas do sul do Brasil funcionam como locais de reprodução, berçários e de crescimento de uma variedade de organismos, incluindo duas das mais importantes espécies de camarões comerciais do Atlântico Sul Ocidental. Camarões foram coletados no Saco dos Limões, Baía Sul, Florianópolis, Estado de Santa Catarina, trimestralmente, de dia e de noite, entre 1997 e 2006. Flutuações em abundâncias de camarões podem estar relacionados aos seus ciclos de vida, com as maiores abundâncias no verão e primavera, ao invés de impactos promovidos pelas atividades de dragagem durante a construção da via expressa.

  2. [Distribution, population parameters, and diet of Astropecten marginatus (Asteroidea: Astropectinidae) in the Venezuelan Atlantic coast].

    Science.gov (United States)

    Ortega, Ileana; Martín, Alberto; Díaz, Yusbelly

    2011-03-01

    Astropecten marginatus is a sea star widely distributed in Northern and Eastern South America, found on sandy and muddy bottoms, in shallow and deep waters. To describe some of its ecological characteristics, we calculated it spatial-temporal distribution, population parameters (based on size and weight) and diet in the Orinoco Delta ecoregion (Venezuela). The ecoregion was divided in three sections: Golfo de Paria, Boca de Serpiente and Plataforma Deltana. Samples for the rainy and dry seasons came from megabenthos surveys of the "Línea Base Ambiental Plataforma Deltana (LBAPD)" and "Corocoro Fase I (CFI)" projects. The collected sea stars were measured, weighted and dissected by the oral side to extract their stomach and identify the preys consumed. A total of 570 sea stars were collected in LBAPD project and 306 in CFI one. The highest densities were found during the dry season in almost all sections. In LBAPD project the highest density was in "Plataforma Deltana" section (0.007 +/- 0.022 ind/m2 in dry season and 0.014 +/- 0.06 ind/m2 in rainy season) and in the CFI project the densities in "Golfo de Paria" section were 0.705 +/- 0.829 ind/m2 in rainy season and 1.027 +/- 1.107 ind/m2 in dry season. The most frequent size range was 3.1-4.6cm. The highest biomass was found in "Golfo de Paria" section (7.581 +/- 0.018 mg/m2 in dry season and 0.005 +/- 6.542 x 10(-06) mg/m2 in rainy season for 2004-2005 and 3.979 +/- 4.024 mg/m2 in dry season; and 3.117 +/- 3.137 mg/m2 in rainy season for 2006). A linear relationship was found between the sea star size and its weight but no relationship was observed between its size and the depth where it was collected. Mollusks are dominant in the sea star diet (47.4% in abundance). The diet in any of the sections, seasons or between projects or size class was heterogeneous, using multivariate ordinations (MDS) and SIMPER analysis and there was no difference in the prey number or food elements that a sea star can eat. Although A

  3. AFSC/REFM: Pacific cod Localized Depletion Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from Localized Depletion study for Pacific cod 2001-2005. Study was conducted using cod pot gear to measure localized abundance of Pacific cod inside and...

  4. Contracaecum osculatum and other anisakid nematodes in grey seals and cod in the Baltic Sea

    DEFF Research Database (Denmark)

    Zuo, S; Kania, P W; Mehrdana, F

    2018-01-01

    Populations of grey seals (Halichoerus grypus), sprats (Sprattus sprattus) and cod (Gadus morhua) in the Baltic Sea are relatively stationary. The present work, applying classical and molecular helminthological techniques, documents that seals and cod also share a common parasite, the anisakid...... nematode Contracaecum osculatum, which uses seals as the final host and fish as transport hosts. Sequencing mitochondrial genes (COX1 and COX2) in adult worms from seals and third-stage larvae from livers of Baltic fish (sprats and cod), showed that all gene variants occur in both seals and fish. Other...... anisakid nematodes Pseudoterranova decipiens and Anisakis simplex are also found in both seals and cod in the Baltic Sea, but at much lower rates. The Baltic grey seal population was left at a critically low level (comprising a few hundred individuals) during the latter part of the 20th century, but since...

  5. Understanding and predicting size selection in diamond-mesh cod ends for danish seining: A study based on sea trials and computer simulations

    DEFF Research Database (Denmark)

    Herrmann, Bent; Krag, Ludvig Ahm; Feekings, Jordan P.

    2016-01-01

    described by a double logistic selection curve, implying that two different size selection processes occur in the cod end. The double selection process could be explained by an additional selection process occurring through slack meshes. The results imply that the escapement of 46% and 34% of the larger...... Atlantic Cod and Haddock (those above 48 cm), respectively, would be through wide-open or slack meshes. Since these mesh states are only likely to be present in the latest stage of the fishing process (e.g., when the cod end is near the surface), a large fraction of the bigger fish probably escaped near...

  6. Molecular phylogeny of the genus Lolliguncula steenstrup, 1881 based on nuclear and mitochondrial DNA sequences indicates genetic isolation of populations from north and South atlantic, and the possible presence of further cryptic species.

    Directory of Open Access Journals (Sweden)

    João Bráullio L Sales

    Full Text Available Squid of the genus Lolliguncula Steenstrup, 1881 are small bodied, coastal species capable of tolerating low salinity. Lolliguncula sp. are found exclusively in the New World, although only one of the four recognized species (Lolliguncula brevis occurs in the Atlantic Ocean. Preliminary morphological analyses suggest that Lolliguncula brevis populations in the North and South Atlantic may represent distinct species. The principal objective of the present study was to verify the phylogenetic relationships within the genus and test for the presence of possible cryptic species. Both gene and species tree topologies indicated that Lolliguncula brevis specimens from the North and South Atlantic represent distinct phylogenetic clades. In contrast with previous studies, L. panamensis was identified as the basal species of the genus. Our results provide important insights into the phylogenetic relationships among the Lolliguncula specimens analyzed, and confirm the genetic separation of Lolliguncula brevis populations of the North and South Atlantic at the level of sister species.

  7. Fish stories: cod, oil and gas turn about to be hard to mix

    International Nuclear Information System (INIS)

    Reid, W.

    2000-01-01

    In 1992 the Government of Canada gave the green light for the start of construction of the Hibernia oil platform; in the same year moratorium on cod fishing was declared. Hibernia ushered in a new era of growth in Atlantic Canada, the moratorium put an end to cod exports for a period of seven years. Environmental activist believe that the two events are not unrelated; after-effects of the Hibernia development played a role in reducing fish stocks and likely to inhibit their recovery. The environmental group 'Save our Seas and Shores' (SOSS) claims that seismic work and drilling are likely to interfere with the migration patterns of young cod, forcing them to spawn in areas that are not safe for egg maturity. According to SOSS, the future of cod fishing is in danger of destruction by further exploration and development in spawning nursery and migratory areas. The group is claiming support from a Nova Scotia government review of two marine ecosystems both of which were declared too delicate to withstand the effects of oil and gas activity. SOSS, supported by a coalition of fishery, native, environmental and tourism groups is determined to halt petroleum exploration along the western coast of Cape Breton Island. In the meantime, the Atlantic Petroleum Institute, first opened in Nova Scotia, and now in the process of expanding into Newfoundland, supported by industry and the Canada Atlantic Opportunities Council, has been assured of funding for a period of five years to develop education and training programs, organize forums for discussion, debate and problem solving, and coordinate research and development. The Institute hopes that SOSS will want to participate in finding solutions to the problems of fisheries that are acceptable to both petroleum and fishing industry interests

  8. Historic changes in length distributions of three Baltic cod (Gadus morhua) stocks: Evidence of growth retardation.

    Science.gov (United States)

    Svedäng, Henrik; Hornborg, Sara

    2017-08-01

    Understanding how combinations of fishing effort and selectivity affect productivity is central to fisheries research. We investigate the roles of fishing regulation in comparison with ecosystem status for Baltic Sea cod stock productivity, growth performance, and population stability. This case study is interesting because three cod populations with different exploitation patterns and stock status are located in three adjacent but partially, ecologically different areas. In assessing stock status, growth, and productivity, we use survey information and rather basic stock parameters without relying on age readings. Because there is an urgent interest of better understanding of the current development of the Eastern Baltic cod stock, we argue that our approach represents partly a novel way of interpreting monitoring information together with catch data in a simplified yet more informative way. Our study reports how the Eastern and Western Baltic cod have gone toward more truncated size structures between 1991 and 2016, in particular for the Eastern Baltic cod, whereas the Öresund cod show no trend. We suggest that selective fishing may disrupt fish population dynamic stability and that lower natural productivity might amplify the effects of selective fishing. In support of earlier findings on a density-dependent growth of Eastern Baltic cod, management is advised to acknowledge that sustainable exploitation levels for Eastern Baltic cod are much more limited than perceived in regular assessments. Of more general importance, our results emphasize the need to embrace a more realistic view on what ecosystems can produce regarding tractable fish biomass to facilitate a more ecosystem-based fisheries management.

  9. Atlantic Region

    NARCIS (Netherlands)

    Elands, B.H.M.; Bell, S.; Blok, J.

    2010-01-01

    Chapter 2 explores recreation and tourism practices in forest areas in the Atlantic region, which refers to the geographical area close to the North Sea and the Atlantic Ocean. The Atlantic countries described in this section are Belgium (Flanders and Wallonia), Denmark, Iceland, Ireland, the

  10. Distribution of mtDNA haplotypes in North-Atlantic humpback whales : The influence of behavior on population structure

    NARCIS (Netherlands)

    Palsboll, PJ; Clapham, PJ; Mattila, DK; Larsen, F; Sears, R; Siegismund, HR; Sigurjonsson, J; Vasquez, O; Arctander, P

    Samples from 136 humpback whales Megaptera novaeangliae, representing 5 feeding aggregations in the North Atlantic and 1 in the Antarctic, were analyzed with respect to the sequence variation in the mitochondrial (mt) control region. A total of 288 base pairs was sequenced by direct sequencing of

  11. Host size-dependent anisakid infection in Baltic cod Gadus morhua associated with differential food preferences

    DEFF Research Database (Denmark)

    Zuo, Shaozhi; Huwer, Bastian; Bahlool, Qusay

    2016-01-01

    A significant increase in the infection level of Baltic cod Gadus morhua with the anisakid nematode larvae Contracaecum osculatum and Pseudoterranova decipiens has been recorded during recent years due to the expanding local population of grey seals Halichoerus grypus, which act as final hosts......). A third nematode Hysterothylacium aduncum was rarely found. The study indicates that the prey animals for large cod act as transport hosts for the parasite larvae. Analyses of stomach contents of cod caught in the same area (2007-2014) showed that small benthic organisms (including polychaetes Harmothoë...... suggest that the C. osculatum life cycle in the Baltic Sea includes grey seals as final hosts, sprat as the first transport host and cod as second transport host. It may be speculated that sprat obtain infection by feeding on copepods and/or cladocerans, which could serve as the first intermediate hosts...

  12. COD and colour removal from molasses spent wash using activated ...

    African Journals Online (AJOL)

    The removal of COD and colour from a melanoidin solution with this activated carbon was carried out using an experimental design taking 4 factors into account. These were adsorbent dose, contact time, pH and initial COD concentration, with removal of COD and colour as response variables. COD reduction was ...

  13. Multidecadal trends in the nesting phenology of Pacific and Atlantic leatherback turtles are associated with population demography

    OpenAIRE

    Robinson, Nathan J.; Valentine, Sara E.; Santidrián Tomillo, Pilar; Saba, Vincent S.; Spotila, James R.; Paladino, Frank V.

    2013-01-01

    Knowledge of the mechanisms influencing phenology can provide insights into the adaptability of species to climate change. Here, we investigated the factors influencing multidecadal trends in the nesting phenology of the leatherback turtle Dermochelys coriacea at Playa Grande, Costa Rica, in the eastern Pacific Ocean and at Sandy Point, US Virgin Islands, in the western Atlantic Ocean. Between 1993 and 2013, the median nesting date (MND) at Playa Grande occurred later, at a rate of ~0.3 d yr-...

  14. AHR-related activities in a creosote-adapted population of adult atlantic killifish, Fundulus heteroclitus, two decades post-EPA superfund status at the Atlantic Wood Site, Portsmouth, VA USA

    Energy Technology Data Exchange (ETDEWEB)

    Wojdylo, Josephine V. [Department of Biological Sciences, Environmental Toxicology Graduate Program, Clemson University, Clemson, SC 29634 (United States); Vogelbein, Wolfgang [The College of William & Mary, Gloucester Point, VA 23062 (United States); Bain, Lisa J. [Department of Biological Sciences, Environmental Toxicology Graduate Program, Clemson University, Clemson, SC 29634 (United States); Rice, Charles D., E-mail: cdrice@clemson.edu [Department of Biological Sciences, Environmental Toxicology Graduate Program, Clemson University, Clemson, SC 29634 (United States)

    2016-08-15

    Highlights: • AHR-related activities in creosote-adapted adult killifish were examined. • Creosote-adapted adult killifish have elevated intestine CYP1A. • Creosote-adapted adult killifish have elevated liver COX2 mRNA expression. • Most creosote-adapted adult killifish have lesions varying in severity. • Liver lesions in creosote-adapted adult killifish express CYP1A and AHR2 proteins. - Abstract: Atlantic killifish, Fundulus heteroclitus, are adapted to creosote-based PAHs at the US EPA Superfund site known as Atlantic Wood (AW) on the southern branch of the Elizabeth River, VA USA. Subsequent to the discovery of the AW population in the early 1990s, these fish were shown to be recalcitrant to CYP1A induction by PAHs under experimental conditions, and even to the time of this study, killifish embryos collected from the AW site are resistant to developmental deformities typically associated with exposure to PAHs in reference fish. Historically, however, 90 +% of the adult killifish at this site have proliferative hepatic lesions including cancer of varying severity. Several PAHs at this site are known to be ligands for the aryl hydrocarbon receptor (AHR). In this study, AHR-related activities in AW fish collected between 2011 and 2013 were re-examined nearly 2 decades after first discovery. This study shows that CYP1A mRNA expression is three-fold higher in intestines of AW killifish compared to a reference population. Using immunohistochemistry, CYP1A staining in intestines was uniformly positive compared to negative staining in reference fish. Livers of AW killifish were examined by IHC to show that CYP1A and AHR2 protein expression reflect lesions-specific patterns, probably representing differences in intrinsic cellular physiology of the spectrum of proliferative lesions comprising the hepatocarcinogenic process. We also found that COX2 mRNA expression levels were higher in AW fish livers compared to those in the reference population, suggesting a

  15. Walking the cod: an investigation into the relative robustness of cod, Gadus morhua, skeletal elements

    Directory of Open Access Journals (Sweden)

    Andrew K.G. Jones

    1999-12-01

    Full Text Available A simple experiment is described which details what happens to the bones of cod when they are walked on by a man. The pattern of fragmentation for various elements is illustrated and an index of robustness proposed for those elements in a cod skeleton most frequently recovered from archaeological sites.

  16. Exploring neutral and adaptive processes in expanding populations of gilthead sea bream, Sparus aurata L., in the North-East Atlantic.

    Science.gov (United States)

    Coscia, I; Vogiatzi, E; Kotoulas, G; Tsigenopoulos, C S; Mariani, S

    2012-05-01

    Recent studies in empirical population genetics have highlighted the importance of taking into account both neutral and adaptive genetic variation in characterizing microevolutionary dynamics. Here, we explore the genetic population structure and the footprints of selection in four populations of the warm-temperate coastal fish, the gilthead sea bream (Sparus aurata), whose recent northward expansion has been linked to climate change. Samples were collected at four Atlantic locations, including Spain, Portugal, France and the South of Ireland, and genetically assayed using a suite of species-specific markers, including 15 putatively neutral microsatellites and 23 expressed sequence tag-linked markers, as well as a portion of the mitochondrial DNA (mtDNA) control region. Two of the putatively neutral markers, Bld-10 and Ad-10, bore signatures of strong directional selection, particularly in the newly established Irish population, although the potential 'surfing effect' of rare alleles at the edge of the expansion front was also considered. Analyses after the removal of these loci suggest low but significant population structure likely affected by some degree of gene flow counteracting random genetic drift. No signal of historic divergence was detected at mtDNA. BLAST searches conducted with all 38 markers used failed to identify specific genomic regions associated to adaptive functions. However, the availability of genomic resources for this commercially valuable species is rapidly increasing, bringing us closer to the understanding of the interplay between selective and neutral evolutionary forces, shaping population divergence of an expanding species in a heterogeneous milieu.

  17. Analysing migrations of Atlantic cod Gadus morhua in the north‐east Atlantic Ocean

    DEFF Research Database (Denmark)

    Neuenfeldt, S.; Righton, D.; Neat, F.

    2013-01-01

    The application of data storage tags bears the potential for a quantum leap in the research on fish migrations, because not only first-capture and recapture positions are known, but at least theoretically, the migration path during the period at large can be reconstructed. Position, however, cannot...

  18. Annual and spatial variability in endo- and ectoparasite infections of North Sea cod (Gadus morhua Linnaeus, 1758) larvae, post-larvae and juveniles

    DEFF Research Database (Denmark)

    Mehrdana, Foojan; Bahlool, Qusay Z. M.; Skovgaard, Alf

    2014-01-01

    A parasitological investigation was performed on a total of 5380 Atlantic cod larvae, post-larvae and small juveniles sampled from the North Sea during a period of five years. The copepod Caligus elongatus (Von Nordmann, 1832) and the nematode Hysterothylacium aduncum (Rudolphi, 1802) were found ...

  19. Sensory characteristics of different cod products

    DEFF Research Database (Denmark)

    Sveinsdottir, K.; Martinsdottir, E.; Hyldig, Grethe

    2010-01-01

    atmosphere) were evaluated with quantitative descriptive analysis by a trained sensory panel. Signal-to-noise analysis, p*MSE (discrimination and repeatability) and line plots proved to be very useful in studying panelists' performance. Most sensory attributes described significant differences between...... the products, and principal component analysis provided an overview of the differences and similarities between the products with regard to sensory characteristics. Farmed cod had different sensory characteristics compared with wild cod, such as more meat flavor, and rubbery and meaty texture. Different...... storage methods had minor influence on sensory characteristics of cod fillets after short storage time, but after extended storage, the groups were different with regard to most attributes. PRACTICAL APPLICATIONS This paper presents different ways of analyzing sensory data. The process of analysis...

  20. 137CS in cod from Barents sea

    International Nuclear Information System (INIS)

    Kellermann, H.-J.; Kanisch, G.; Krueger, A.

    2003-01-01

    After publication of the Yablovkov report about dumping of radioactive waste by the former Soviet Union the Institute for Fishery Ecology has analysed fish from Barents Sea for radioactivity. In all studies 137 Cs concentrations in cod fillet showed a clear dependance from fish length. Results from an analysis of covariance for cod of 70 cm length have minor changes within Barents Sea and indicate a rapid decay to a value as is expected for marine fish which is only influenced by global fallout. (orig.)

  1. Two distinct mtDNA lineages of the blue crab reveal large-scale population structure in its native Atlantic distribution

    Science.gov (United States)

    Alaniz Rodrigues, Marcos; Dumont, Luiz Felipe Cestari; dos Santos, Cléverson Rannieri Meira; D'Incao, Fernando; Weiss, Steven; Froufe, Elsa

    2017-10-01

    For the first time, a molecular approach was used to evaluate the phylogenetic structure of the disjunct native American distribution of the blue crab Callinectes sapidus. Population structure was investigated by sequencing 648bp of the Cytochrome oxidase subunit 1 (COI), in a total of 138 sequences stemming from individual samples from both the northern and southern hemispheres of the Western Atlantic distribution of the species. A Bayesian approach was used to construct a phylogenetic tree for all samples, and a 95% confidence parsimony network was created to depict the relationship among haplotypes. Results revealed two highly distinct lineages, one containing all samples from the United States and some from Brazil (lineage 1) and the second restricted to Brazil (lineage 2). In addition, gene flow (at least for females) was detected among estuaries at local scales and there is evidence for shared haplotypes in the south. Furthermore, the findings of this investigation support the contemporary introduction of haplotypes that have apparently spread from the south to the north Atlantic.

  2. Evolutionary history of a dispersal-associated locus across sympatric and allopatric divergent populations of a wing-polymorphic beetle across Atlantic Europe.

    Science.gov (United States)

    Van Belleghem, Steven M; Roelofs, Dick; Hendrickx, Frederik

    2015-02-01

    Studying the evolutionary history of trait divergence, in particular those related to dispersal capacity, is of major interest for the process of local adaptation and metapopulation dynamics. Here, we reconstruct the evolution of different alleles at the nuclear-encoded mitochondrial NADP(+)-dependent isocitrate dehydrogenase (mtIdh) locus of the ground beetle Pogonus chalceus that are differentially and repeatedly selected in short- and long-winged populations in response to different hydrological regimes at both allopatric and sympatric scales along the Atlantic European coasts. We sequenced 2788 bp of the mtIdh locus spanning a ~7-kb genome region and compared its variation with that of two supposedly neutral genes. mtIdh sequences show (i) monophyletic clustering of the short-winged associated mtIDH-DE haplotypes within the long-winged associated mtIDH-AB haplotypes, (ii) a more than tenfold lower haplotype diversity associated with the mtIDH-DE alleles compared to the mtIDH-AB alleles and (iii) a high number of fixed nucleotide differences between both mtIDH haplotype clusters. Coalescent simulations suggest that this observed sequence variation in the mtIdh locus is most consistent with a singular origin in a partially isolated subpopulation, followed by a relatively recent spread of the mtIDH-DE allele in short-winged populations along the Atlantic coast. These results demonstrate that even traits associated with decreased dispersal capacity can rapidly spread and that reuse of adaptive alleles plays an important role in the adaptive potential within this sympatric mosaic of P. chalceus populations. © 2014 John Wiley & Sons Ltd.

  3. New insights about the population structure of the blue jack mackerel (Trachurus picturatus in the NE Atlantic using otolith stable isotope ratios

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    Cláudia Moreira

    2015-11-01

    Full Text Available The blue jack mackerel Trachurus picturatus is a pelagic fish widely distributed in the NE Atlantic and also found in the Mediterranean and Black Seas. It is an economically important resource in the Macaronesian islands of Azores, Madeira and Canaries, but despite its fishery value and ecological importance, fluctuations in the landings are difficult to explain since studies regarding the population dynamics, stocks structure, fish movements and habitat connectivity are inexistent. The populations of marine pelagic fishes, in particular the migratory ones, such as T. picturatus,, may be erroneously considered an homogenous population unit because they show broad geographic distributions, large population sizes and high migratory movements. Stable isotope ratios, namely δ18O and δ13C, measured by standard mass spectrometric techniques in whole otolith samples of T. picturatus adults sampled in the fishery grounds of the Islands of Azores, Madeira and Canaries, and at the Portuguese mainland (Matosinhos, Peniche and Portimão during the spring-summer of 2013 were analysed. The 18O signatures followed the general tendency taking into account the seawater temperatures of the sampling regions. 13C signatures showed however differences between the oceanic or continental origin of the fish. Both variables provided location-specific signatures. Further studies including mitochondrial and nuclear DNA studies are also been conducted to acquire new knowledge for fisheries conservation purposes.

  4. Artificial nests as an alternative to studies of arboreal small mammal populations: a five-year study in the Atlantic Forest, Brazil

    Directory of Open Access Journals (Sweden)

    Diogo Loretto

    2011-06-01

    Full Text Available Despite the great diversity of Brazilian Atlantic forest small mammals, natural history of most species is unknown due to their cryptic and nocturnal habits, but also due to the inadequacy of methods to capture some species, especially those of arboreal habits. A new technique, based on the use of artificial nests (AN to record arboreal marsupials, is presented. Artificial nests were combined with traditional live traps to study the population ecology of four didelphid marsupial species. After 62 months of monitoring, 119 individuals were recorded 243 times (total success = 5.2%. Only 26 individuals (22% were recorded by both AN and live trap methods, and two of the four species were never captured by live traps, only by AN. Live traps alone would have provided biased data of the structure of small mammal assemblages, creating artificial tendencies in population dynamics of many species. Detectability estimates based on mark-recapture data could correct bias resulting from the use only live traps, but these estimates require that at least some individuals of each age class or stage are captured. Only the combination of AN and live traps can produce more accurate data on population dynamics and assemblage structure. This study demonstrates that artificial nests represent a new method that should be combined with live traps in studies of small mammal assemblages and populations.

  5. Influence of the North Atlantic oceanograghic and climatic parameters on the Spanish European Eel population recruitment: relationships in the past and for a future climate change

    Science.gov (United States)

    Ribalaygua, Jaime; Pórtoles, Javier; Monjo, Robert; Díaz, Estíbaliz; Korta, María; Chust, Guillem

    2016-04-01

    The status of the European eel population is critical.; the annual recruitment of glass eel to European waters in 2015 is 1.2% of the 1960-1979 level in the 'North Sea' area, and 8.4% in the rest of Europe (ICES 2015) . There are a number of anthropogenic impacts potentially affecting eel population including commercial exploitation, habitat loss, dam and weir construction, hydropower, pumping stations and surface water abstractions. Furthermore, the first eel stages and larval migration and marine survival are heavily influenced by oceanic and climatic factors since the species breeds in the Sargasso Sea and migrates to the continental shelf of the Atlantic coast of Europe and North Africa. Therefore, the study of the relations between recruitment and oceanic conditions may allow to study the potential effect of climatic change on the future eel recruitment and therefore stock. In the present study, the relation between glass eel recruitment and oceanic and climatic factors has been studied. Historic glass eel catches data beginning in the 50s from two Mediterranean and two Atlantic estuaries have been used as a proxy of recruitment. The relation of catches with the main oceanographic and climatic factors identified in the literature was established using an ocean reanalysis, the Simple Ocean Data Assimilation (SODA) and determined which variables are significantly related to the number of catches. The analysis shows significant relationships between catches and oceanic (Surface Downward Stress, Sea Water Temperature and Sea Water Velocity) and atmospheric (NAO Index, AMO Index) variables. Subsequently, we applied the results of three climate models (GFDL-ESM2M, CanESM2 and CNRM-CM5), associated with the Coupled Model Intercomparison Project Phase 5 (CMIP5) under two simulations of climate change (RCP4.5 and RCP8.5), both associated with the 5th Assessment Report of the IPCC, for possible future influences on the eel. This research was funded by the Spanish

  6. Assessment of a land-locked Atlantic salmon (Salmo salar L.) population as a potential genetic resource with a focus on long-chain polyunsaturated fatty acid biosynthesis.

    Science.gov (United States)

    Betancor, M B; Olsen, R E; Solstorm, D; Skulstad, O F; Tocher, D R

    2016-03-01

    The natural food for Atlantic salmon (Salmo salar) in freshwater has relatively lower levels of omega-3 (n-3) long-chain polyunsaturated fatty acids (LC-PUFA) than found in prey for post-smolt salmon in seawater. Land-locked salmon such as the Gullspång population feed exclusively on freshwater type lipids during its entire life cycle, a successful adaptation derived from divergent evolution. Studying land-locked populations may provide insights into the molecular and genetic control mechanisms that determine and regulate n-3 LC-PUFA biosynthesis and retention in Atlantic salmon. A two factorial study was performed comparing land-locked and farmed salmon parr fed diets formulated with fish or rapeseed oil for 8 weeks. The land-locked parr had higher capacity to synthesise n-3 LC-PUFA as indicated by higher expression and activity of desaturase and elongase enzymes. The data suggested that the land-locked salmon had reduced sensitivity to dietary fatty acid composition and that dietary docosahexaenoic acid (DHA) did not appear to suppress expression of LC-PUFA biosynthetic genes or activity of the biosynthesis pathway, probably an evolutionary adaptation to a natural diet lower in DHA. Increased biosynthetic activity did not translate to enhanced n-3 LC-PUFA contents in the flesh and diet was the only factor affecting this parameter. Additionally, high lipogenic and glycolytic potentials were found in land-locked salmon, together with decreased lipolysis which in turn could indicate increased use of carbohydrates as an energy source and a sparing of lipid. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Plasma levels of pollutants are much higher in loggerhead turtle populations from the Adriatic Sea than in those from open waters (Eastern Atlantic Ocean).

    Science.gov (United States)

    Bucchia, Matteo; Camacho, María; Santos, Marcelo R D; Boada, Luis D; Roncada, Paola; Mateo, Rafael; Ortiz-Santaliestra, Manuel E; Rodríguez-Estival, Jaime; Zumbado, Manuel; Orós, Jorge; Henríquez-Hernández, Luis A; García-Álvarez, Natalia; Luzardo, Octavio P

    2015-08-01

    In this paper we determined the levels of 63 environmental contaminants, including organic (PCBs, organochlorine pesticides, and PAHs) and inorganic (As, Cd, Cu, Pb, Hg and Zn) compounds in the blood of loggerhead turtles (Caretta caretta) from two comparable populations that inhabit distinct geographic areas: the Adriatic Sea (Mediterranean basin) and the Canary Islands (Eastern Atlantic Ocean). All animals were sampled at the end of a period of rehabilitation in centers of wildlife recovery, before being released back into the wild, so they can be considered to be in good health condition. The dual purpose of this paper is to provide reliable data on the current levels of contamination of this species in these geographic areas, and secondly to compare the results of both populations, as it has been reported that marine biota inhabiting the Mediterranean basin is exposed to much higher pollution levels than that which inhabit in other areas of the planet. According to our results it is found that current levels of contamination by organic compounds are considerably higher in Adriatic turtles than in the Atlantic ones (∑PCBs, 28.45 vs. 1.12ng/ml; ∑OCPs, 1.63 vs. 0.19ng/ml; ∑PAHs, 13.39 vs. 4.91ng/ml; pmercury (5.74 vs. 7.59μg/ml, p<0.01). The results of this study confirm that the concentrations are larger in turtles from the Mediterranean, probably related to the high degree of anthropogenic pressure in this basin, and thus they are more likely to suffer adverse effects related to contaminants. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. L’écodéveloppement participatif en question

    Directory of Open Access Journals (Sweden)

    Lucie Dejouhanet

    2010-03-01

    Full Text Available Si les politiques forestières indiennes ont évolué d’un paradigme directif à un paradigme participatif, les aires protégées sont encore gérées par des textes de loi qui privilégient la séparation entre activités humaines et espaces à protéger. L’écodéveloppement, soutenu par la Banque Mondiale, se voulait un moyen de favoriser des activités alternatives à l’exploitation des ressources et de faire participer les populations à la protection de leur environnement. Lancé en 2001 dans la réserve naturelle de Parambikulam au Kérala, ses résultats quelques années après sont peu concluants. Alors qu’un rapport de 2003 accuse le délitement social des populations concernées, cet article insiste davantage sur l’inadaptation des projets des comités d’écodéveloppement au contexte des villages ; le cliché essentialiste attaché aux populations adivasi constitue une vision a-historique qui ne permet pas de penser le développement aujourd’hui. L’écodéveloppement, s’il veut atteindre ses objectifs, doit permettre une réelle négociation entre acteurs des aires protégées et proposer des compromis réalistes entre limitation des activités et survie des populations.While Indian forest policies have evolved from a directive paradigm to a participative one, protected areas are still managed by legislative acts, which advocate a clear separation between human activities and areas to be protected. Eco-development financed by the World Bank was planned as a tool for developing alternative activities to resource exploitation and for involving local populations in environment protection through participation. Started in 2001 in the Wildlife Sanctuary of Parambikulam in Kerala, its results few years after are rather inconclusive. While a report in 2003 was accusing the social disintegration of concerned people, I am more stressing on the inappropriateness of EDC to villages’ context. The essentialist clich

  9. Use of existing hydrographic infrastructure to forecast the environmental spawning conditions for Eastern Baltic cod.

    Science.gov (United States)

    von Dewitz, Burkhard; Tamm, Susanne; Höflich, Katharina; Voss, Rüdiger; Hinrichsen, Hans-Harald

    2018-01-01

    The semi-enclosed nature and estuarine characteristics, together with its strongly alternating bathymetry, make the Baltic Sea prone to much stronger interannual variations in the abiotic environment, than other spawning habitats of Atlantic cod (Gadus morhua). Processes determining salinity and oxygen conditions in the basins are influenced both by long term gradual climate change, e.g. global warming, but also by short-term meteorological variations and events. Specifically one main factor influencing cod spawning conditions, the advection of highly saline and well-oxygenated water masses from the North Sea, is observed in irregular frequencies and causes strong interannual variations in stock productivity. This study investigates the possibility to use the available hydrographic process knowledge to predict the annual spawning conditions for Eastern Baltic cod in its most important spawning ground, the Bornholm Basin, only by salinity measurements from a specific location in the western Baltic. Such a prediction could serve as an environmental early warning indicator to inform stock assessment and management. Here we used a hydrodynamic model to hindcast hydrographic property fields for the last 40+ years. High and significant correlations were found for months early in the year between the 33m salinity level in the Arkona Basin and the oxygen-dependent cod spawning environment in the Bornholm Basin. Direct prediction of the Eastern Baltic cod egg survival in the Bornholm Basin based on salinity values in the Arkona Basin at the 33 m depth level is shown to be possible for eggs spawned by mid-age and young females, which currently predominate the stock structure. We recommend to routinely perform short-term predictions of the Eastern Baltic cod spawning environment, in order to generate environmental information highly relevant for stock dynamics. Our statistical approach offers the opportunity to make best use of permanently existing infrastructure in the

  10. Assessing impacts of simulated oil spills on the Northeast Arctic cod fishery.

    Science.gov (United States)

    Carroll, JoLynn; Vikebø, Frode; Howell, Daniel; Broch, Ole Jacob; Nepstad, Raymond; Augustine, Starrlight; Skeie, Geir Morten; Bast, Radovan; Juselius, Jonas

    2018-01-01

    We simulate oil spills of 1500 and 4500m 3 /day lasting 14, 45, and 90days in the spawning grounds of the commercial fish species, Northeast Arctic cod. Modeling the life history of individual fish eggs and larvae, we predict deviations from the historical pattern of recruitment to the adult population due to toxic oil exposures. Reductions in survival for pelagic stages of cod were 0-10%, up to a maximum of 43%. These reductions resulted in a decrease in adult cod biomass of <3% for most scenarios, up to a maximum of 12%. In all simulations, the adult population remained at full reproductive potential with a sufficient number of juveniles surviving to replenish the population. The diverse age distribution helps protect the adult cod population from reductions in a single year's recruitment after a major oil spill. These results provide insights to assist in managing oil spill impacts on fisheries. Copyright © 2017 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  11. Extrusion of Contracaecum osculatum nematode larvae from the liver of cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Zuo, S.; Barlaup, L.; Mohammadkarami, A.

    2017-01-01

    Baltic cod livers have during recent years been found increasingly and heavily infected with third-stage larvae of Contracaecum osculatum. The infections are associated with an increasing population of grey seals which are final hosts for the parasite. Heavy worm burdens challenge utilization...

  12. Genetic differentiation in geographically close populations of the water rat Nectomys squamipes (Rodentia, Sigmodontinae from the Brazilian Atlantic Forest

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    Maroja L.S.

    2003-01-01

    Full Text Available We examined the genetic structure and the effects of a bottleneck in populations of the water rat Nectomys squamipes, a primary host of Schistosoma mansoni. Eight microsatellite loci were studied in 7 populations from the Sumidouro region of the Brazilian state of Rio de Janeiro. Our data, covering a four-year period during which a bottleneck occurred, revealed substantial variation (6-31 alleles per locus and high levels of both observed (0.718-0.789 and expected (0.748-0.832 heterozygosity. Most populations were in Hardy-Weinberg equilibrium without linkage disequilibrium between loci. Overall average genetic differentiation between populations (estimated with the F ST (q and R ST (r analogues was 0.037 for q and 0.060 for r. There was significant allelic and genotypic differentiation between populations, especially in pairwise comparisons that included the most geographically isolated population. Direct migration estimates showed a low rate of migration, indicating that infected N. squamipes populations had a limited ability to spread S. mansoni. When the pre- and post-bottleneck populations were compared there was no detectable reduction in heterozygosity or allele number, although a significant excess of heterozygosity was detected in the post-bottleneck population.

  13. Mapping the spawning grounds of North Sea cod (Gadus morhua) by direct and indirect means.

    Science.gov (United States)

    Fox, Clive J; Taylor, Martin; Dickey-Collas, Mark; Fossum, Petter; Kraus, Gerd; Rohlf, Norbert; Munk, Peter; van Damme, Cindy J G; Bolle, Loes J; Maxwell, David L; Wright, Peter J

    2008-07-07

    Despite recent evidence for sub-stock structuring, North Sea cod are assessed as a single unit. As a consequence, knowledge of sub-stock trends is poor. In particular, there are no recent evaluations of which spawning grounds are active. Here we report results from the first ichthyoplankton survey to cover the whole North Sea. Also, this survey, conducted in 2004, was the first to make extensive use of DNA-based molecular methods to unambiguously identify early developmental stage cod eggs. We compare the findings from the plankton survey with estimated egg production inferred from the distribution of mature cod in contemporaneous trawl surveys. Results from both approaches were in general agreement and showed hot spots of egg production around the southern and eastern edges of the Dogger Bank, in the German Bight, the Moray Firth and to the east of the Shetlands. These areas broadly coincide with known spawning locations from the period 1940 to 1970. We were, however, unable to directly detect significant numbers of cod eggs at the historic spawning ground off Flamborough (northeast coast of England). The results demonstrate that most of the major spawning grounds of cod in the North Sea are still active but that some localized populations may have been reduced to the point where it is now difficult to detect the presence of eggs in the plankton.

  14. Explaining the catch efficiency of different cod pots using underwater video to observe cod entry and exit behaviour

    DEFF Research Database (Denmark)

    Hedgärde, Maria; Berg, Casper Willestofte; Kindt-Larsen, Lotte

    2016-01-01

    Cod pots are considered seal-safe fishing gear and are proposed as a solution to mitigate the ongoing seal-fisheries conflict in the Baltic Sea. This study examined various factors which could affect the entry and exit behaviour of cod in relation to cod pots. Statistical modelling was used...

  15. Model-based analyses reveal insular population diversification and cryptic frog species in the Ischnocnema parva complex in the Atlantic forest of Brazil.

    Science.gov (United States)

    Gehara, Marcelo; Barth, Adriane; Oliveira, Eliana Faria de; Costa, Marco Antonio; Haddad, Célio Fernando Baptista; Vences, Miguel

    2017-07-01

    The Atlantic Forest (AF) of Brazil has long been recognized as a biodiversity conservation hotspot. Despite decades of studies the species inventory of this biome continues to increase with the discovery of cryptic diversity and the description of new species. Different diversification mechanisms have been proposed to explain the diversity in the region, including models of forest dynamics, barriers to gene flow and dispersal. Also, sea level change is thought to have influenced coastal diversification and isolated populations on continental islands. However, the timing and mode of diversification of insular populations in the AF region were rarely investigated. Here, we analyze the phylogeography and species diversity of the small-sized direct-developing frog Ischnocnema parva. These frogs are independent from water bodies but dependent on forest cover and high humidity, and provide good models to understand forest dynamics and insular diversification. Our analysis was based on DNA sequences for one mitochondrial and four nuclear genes of 71 samples from 18 localities including two islands, São Sebastião, municipality of Ilhabela, and Mar Virado, municipality of Ubatuba, both in the state of São Paulo. We use molecular taxonomic methods to show that I. parva is composed of six independently evolving lineages, with the nominal I. parva likely endemic to the type locality. The time-calibrated species tree shows that these lineages have diverged in the Pliocene and Pleistocene, suggesting the persistence of micro-refuges of forest in the AF. For the two insular populations we used approximate Bayesian computation to test different diversification hypotheses. Our findings support isolation with migration for São Sebastião population, with ∼1Mya divergence time, and isolation without migration for Mar Virado population, with ∼13Kya divergence time, suggesting a combination of different processes for diversification on AF islands. Copyright © 2017. Published

  16. Selective haddock (Melanogrammus aeglefinus) trawling: Avoiding cod (Gadus morhua) bycatch

    DEFF Research Database (Denmark)

    Krag, Ludvig Ahm; Holst, René; Madsen, Niels

    2010-01-01

    The critical condition of the North Sea cod stocks has resulted in restrictions on not only cod, but also haddock and other species that are caught together with cod. Thus full exploitation of the haddock stock is unachievable unless cod can be excluded from the haddock catch. We designed a selec...... dependent: smaller cod escaped the trawl in greater numbers than did larger individuals. Whiting, saithe. lemon sole, and plaice were included in the analysis. (C) 2009 Elsevier B.V. All rights reserved....

  17. Restricted fish feeding reduces cod otolith opacity

    DEFF Research Database (Denmark)

    Høie, H.; Folkvord, A.; Mosegaard, Henrik

    2008-01-01

    The purpose of this work was to examine the effect of reduced feeding and constant temperature on cod otolith opacity. Three groups of juvenile cod were given restricted food rations at different times for 4 months, resulting in depressed somatic growth. Otolith opacity was measured on pictures...... in otolith opacity were found between individual fish both within groups and between groups. In two of the three groups significantly more translucent otolith material was deposited in response to reduced feeding. Our results show that variations in feeding and hence fish growth resulted in variation...... in otolith opacity, but the effect was minor compared to that of variations in ambient temperature. The combined influence of these effects, which both act on fish metabolism, are most likely controlling the seasonal opacity changes observed in wild fish. Our results help explain the variations seen in fish...

  18. Northeast arctic cod stock and fishery dynamics

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    Oleg Bulatov

    2015-12-01

    Full Text Available Northeast arctic cod stock is one of a most valuable target of fisheries in the Barents Sea. The catches of cod for the period 1960-2014 are widely changed. The minimum level of catches is marked in 1990 (212 thousands ton, and the maximum values of catches were observed in 1969 – 1.2 mill. ton. In the recent years international catch of cod exceeded 1 mill. ton. Fishable and spawning stock biomass (SSB also widely changed in this period. According to ICES data, SSB had a minimum in 1965 (102 thousand tons, and extremely high level in 2013 – 2 150 thousand tons. Fishable biomass changed also widely. The maximum level is registered in 2013 – 3 636 thousand tons, and minimum value was 5 times less, 739 thousand tons (1983. The ratio between historical high level of SSB and catch in 2013 was 2.2:1.0, due to low value of fishing mortality. Possibility to increase catch will be discussed.

  19. Helminth parasite communities of two Physalaemus cuvieri Fitzinger, 1826 (Anura: Leiuperidae populations under different conditions of habitat integrity in the Atlantic Rain Forest of Brazil

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    A. Aguiar

    Full Text Available Abstract Adults of Physalaemus cuvieri were collected and necropsied between November 2009 and January 2010. This was carried out in order to report and compare the helminth fauna associated with two populations of this anuran species from the Brazilian Atlantic rain forest under different conditions of habitat integrity. The hosts from the disturbed area were parasitized with five helminth taxa: Cosmocerca parva, Aplectana sp., Physaloptera sp., Rhabdias sp., Oswaldocruzia subauricularis (Nematoda and Polystoma cuvieri (Monogenea while those from the preserved area had four helminth taxa: C. parva, Aplectana sp., Physaloptera sp., Rhabdias sp., and Acanthocephalus saopaulensis (Acanthocephala. Prevalence, mean intensity of infection, mean abundance, mean richness, importance index and dominance frequency of helminth component communities were similar in both areas. The helminth community associated with anurans from the disturbed area had higher diversity than that from the preserved area. This study is the first to report on the acanthocephalan parasites of Ph. cuvieri, and the similarity between helminth fauna composition of two host populations under different selective pressures.

  20. Holocene re-colonisation, central-marginal distribution and habitat specialisation shape population genetic patterns within an Atlantic European grass species.

    Science.gov (United States)

    Harter, D E V; Jentsch, A; Durka, W

    2015-05-01

    Corynephorus canescens (L.) P.Beauv. is an outbreeding, short-lived and wind-dispersed grass species, highly specialised on scattered and disturbance-dependent habitats of open sandy sites. Its distribution ranges from the Iberian Peninsula over Atlantic regions of Western and Central Europe, but excludes the two other classical European glacial refuge regions on the Apennine and Balkan Peninsulas. To investigate genetic patterns of this uncommon combination of ecological and biogeographic species characteristics, we analysed AFLP variation among 49 populations throughout the European distribution range, expecting (i) patterns of SW European glacial refugia and post-glacial expansion to the NE; (ii) decreasing genetic diversity from central to marginal populations; and (iii) interacting effects of high gene flow and disturbance-driven genetic drift. Decreasing genetic diversity from SW to NE and distinct gene pool clustering imply refugia on the Iberian Peninsula and in western France, from where range expansion originated towards the NE. High genetic diversity within and moderate genetic differentiation among populations, and a significant pattern of isolation-by-distance indicate a gene flow drift equilibrium within C. canescens, probably due to its restriction to scattered and dynamic habitats and limited dispersal distances. These features, as well as the re-colonisation history, were found to affect genetic diversity gradients from central to marginal populations. Our study emphasises the need for including the specific ecology into analyses of species (re-)colonisation histories and range centre-margin analyses. To account for discontinuous distributions, new indices of marginality were tested for their suitability in studies of centre-periphery gradients. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  1. Particulate COD balance of particulate cod in eletrocuagulation/flotation reactor treating tannery effluent

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    Rodrigo Babora Borri

    2012-04-01

    Full Text Available Mass balance or particulate organic matter was studied in terms of COD, by means of electrocoagulation/flotation (ECF reactor treating tannery effluent. Reactor was operated in fill and draw (batch mode. Operating in hydraulic residence time of 65 minutes, ECF reactor reached 55 % COD removal. Although volatile solids were also removed from liquid phase (removal of 40%, fixed solids concentration, and hence total solids concentration, showed to be higher in withdrawn effluent than in ECF’s influent. This was assigned to NaCl added in order to enhance conductivity in wastewater.

  2. Female Choice Undermines the Emergence of Strong Sexual Isolation between Locally Adapted Populations of Atlantic Mollies (Poecilia mexicana

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    Claudia Zimmer

    2018-05-01

    Full Text Available Divergent selection between ecologically dissimilar habitats promotes local adaptation, which can lead to reproductive isolation (RI. Populations in the Poecilia mexicana species complex have independently adapted to toxic hydrogen sulfide and show varying degrees of RI. Here, we examined the variation in the mate choice component of prezygotic RI. Mate choice tests across drainages (with stimulus males from another drainage suggest that specific features of the males coupled with a general female preference for yellow color patterns explain the observed variation. Analyses of male body coloration identified the intensity of yellow fin coloration as a strong candidate to explain this pattern, and common-garden rearing suggested heritable population differences. Male sexual ornamentation apparently evolved differently across sulfide-adapted populations, for example because of differences in natural counterselection via predation. The ubiquitous preference for yellow color ornaments in poeciliid females likely undermines the emergence of strong RI, as female discrimination in favor of own males becomes weaker when yellow fin coloration in the respective sulfide ecotype increases. Our study illustrates the complexity of the (partly non-parallel pathways to divergence among replicated ecological gradients. We suggest that future work should identify the genomic loci involved in the pattern reported here, making use of the increasing genomic and transcriptomic datasets available for our study system.

  3. Long-term changes in deep-water fish populations in the northeast Atlantic: a deeper reaching effect of fisheries?

    OpenAIRE

    Bailey, D.M.; Collins, M.A.; Gordon, J.D.M.; Zuur, A.F.; Priede, I.G.

    2009-01-01

    A severe scarcity of life history and population data for deep-water fishes is a major impediment to successful fisheries management. Long-term data for non-target species and those living deeper than the fishing grounds are particularly rare. We analysed a unique dataset of scientific trawls made from 1977 to 1989 and from 1997 to 2002, at depths from 800 to 4800 m. Over this time, overall fish abundance fell significantly at all depths from 800 to 2500 m, considerably deeper than the maximu...

  4. The impacts of mobile fishing gear on seafloor habitats in the Gulf of Maine (Northwest Atlantic): implications for conservation of fish populations

    Science.gov (United States)

    Auster, Peter J.; Malatesta, Richard J.; Langton, Richard W.; Watting, Les; Valentine, Page C.; Donaldson, Carol Lee S.; Langton, Elizabeth W.; Shepard, Andrew N.; Babb, War G.

    1997-01-01

    Fishing gear alters seafloor habitats, but the extent of these alterations, and their effects, have not been quantified extensively in the northwest Atlantic. Understanding the extent of these impacts, and their effects on populations of living marine resources, is needed to properly manage current and future levels of fishing effort and fishing power. For example, the entire U.S. side of the Gulf of Maine was impacted annually by mobile fishing gear between 1984 and 1990, based on calculations of area swept by trawl and dredge gear. Georges Bank was imparted three to nearly four times annually during the same period. Studies at three sites in the Gulf of Maine (off Swans Island, Jeffreys Bank, and Stellwagen Bank) showed that mobile fishing gear altered the physical structure (=complexity) of benthic habitats. Complexity was reduced by direct removal of biogenic (e.g., sponges, hydrozoans, bryozoans, amphipod tubes, holothurians, shell aggregates) and‐ sedimentary (e.g., sand waves, depressions) structures. Also, removal of organisms that create.structures (e.g., crabs, scallops) indirectly reduced complexity. Reductions in habitat complexity may lead to increased predation on juveniles of harvested species and ultimately recruitment to the harvestable stock. Because of a lack of reference sites, where use of mobile fishing is prohibited, no empirical studies have yet been conducted on a scale that could demonstrate population level effects of habitat‐management options. If marine fisheries management is to evolve toward an ecosystem or habitat management approach, experiments are required on the effects of habitat change, both anthropogenic and natural.

  5. Depletion of trophy large-sized sharks populations of the Argentinean coast, south-western Atlantic: insights from fishers' knowledge

    Directory of Open Access Journals (Sweden)

    Alejo Irigoyen

    Full Text Available Abstract Globally, sharks are impacted by a wide range of human activities, resulting in many populations being depleted. Trophy large-sized sharks of the Argentinean coast, the sand-tiger Carcharias taurus , the copper Carcharhinus brachyurus and the sevengill shark Notorynchus cepedianus are under intense sport and artisanal fishing since the 50's decade. However, the current and historical information for the assessment of its populations status is scarce. The aim of this work was to analyze the status of conservation of these species through the gathering of expert fishermen knowledge (FK on semi-structured interviews. Abundance variation perception between the beginning and the end of fishermen careers revealed a critical status for the species study (means variation between -77 and -90 %. Furthermore, a best day's catch analysis reinforce this result in the case of the sand tiger shark. The school shark Galeorhinus galeus was included on this work with the objective of contrast FK with formal information available of catch-per-unit-effort (CPUE time series. Both sources of information, despite are not comparable, shows declines ~ - 80%. The critical conservation situation of study species needs urgent management action, particularly for the san tiger shark which could became regionally extinct before the reaction of stakeholders occurs.

  6. Contracaecum osculatum and other anisakid nematodes in grey seals and cod in the Baltic Sea: molecular and ecological links.

    Science.gov (United States)

    Zuo, S; Kania, P W; Mehrdana, F; Marana, M H; Buchmann, K

    2018-01-01

    Populations of grey seals (Halichoerus grypus), sprats (Sprattus sprattus) and cod (Gadus morhua) in the Baltic Sea are relatively stationary. The present work, applying classical and molecular helminthological techniques, documents that seals and cod also share a common parasite, the anisakid nematode Contracaecum osculatum, which uses seals as the final host and fish as transport hosts. Sequencing mitochondrial genes (COX1 and COX2) in adult worms from seals and third-stage larvae from livers of Baltic fish (sprats and cod), showed that all gene variants occur in both seals and fish. Other anisakid nematodes Pseudoterranova decipiens and Anisakis simplex are also found in both seals and cod in the Baltic Sea, but at much lower rates. The Baltic grey seal population was left at a critically low level (comprising a few hundred individuals) during the latter part of the 20th century, but since the year 2000 a marked increase in the population has been observed, reaching more than 40,000 individuals at present. Ecological consequences of the increased seal abundance may result from increased predation on fish stocks, but recent evidence also points to the influence of elevated parasitism on fish performance. Contracaecum osculatum larvae preferentially infect the liver of Baltic cod, considered a vital organ of the host. Whereas low prevalences and intensities in cod were reported during the 1980s and 1990s, the present study documents 100% prevalence and a mean intensity of above 80 worms per fish. Recent studies have also indicated the zoonotic potential of C. osculatum larvae in fish, following the consumption of raw or under-cooked fish. Therefore the present work discusses the impact of parasitism on the cod stock and the increasing risk for consumer health, and lists possible solutions for control.

  7. Impacts of Extreme Flooding on Hydrologic Connectivity and Water Quality in the Atlantic Coastal Plain and Implications for Vulnerable Populations

    Science.gov (United States)

    Riveros-Iregui, D. A.; Moser, H. A.; Christenson, E. C.; Gray, J.; Hedgespeth, M. L.; Jass, T. L.; Lowry, D. S.; Martin, K.; Nichols, E. G.; Stewart, J. R.; Emanuel, R. E.

    2017-12-01

    In October 2016, Hurricane Matthew brought extreme flooding to eastern North Carolina, including record regional flooding along the Lumber River and its tributaries in the North Carolina Coastal Plain. Situated in a region dominated by large-scale crop-cultivation and containing some of the highest densities of concentrated animal feeding operations (CAFOs) and animal processing operations in the U.S., the Lumber River watershed is also home to the Lumbee Tribe of American Indians. Most of the tribe's 60,000+ members live within or immediately adjacent to the 3,000 km2 watershed where they maintain deep cultural and historical connections. The region, however, also suffers from high rates of poverty and large disparities in healthcare, education, and infrastructure, conditions exacerbated by Hurricane Matthew. We summarize ongoing efforts to characterize the short- and long-term impacts of extreme flooding on water quality in (1) low gradient streams and riverine wetlands of the watershed; (2) surficial aquifers, which provide water resources for the local communities, and (3) public drinking water supplies, which derive from deeper, confined aquifers but whose infrastructure suffered widespread damage following Hurricane Matthew. Our results provide mechanistic understanding of flood-related connectivity across multiple hydrologic compartments, and provide important implications for how hydrological natural hazards combine with land use to drive water quality impacts and affect vulnerable populations.

  8. CodY-Dependent Regulation of Sporulation in Clostridium difficile.

    Science.gov (United States)

    Nawrocki, Kathryn L; Edwards, Adrianne N; Daou, Nadine; Bouillaut, Laurent; McBride, Shonna M

    2016-08-01

    Clostridium difficile must form a spore to survive outside the gastrointestinal tract. The factors that trigger sporulation in C. difficile remain poorly understood. Previous studies have suggested that a link exists between nutritional status and sporulation initiation in C. difficile In this study, we investigated the impact of the global nutritional regulator CodY on sporulation in C. difficile strains from the historical 012 ribotype and the current epidemic 027 ribotype. Sporulation frequencies were increased in both backgrounds, demonstrating that CodY represses sporulation in C. difficile The 027 codY mutant exhibited a greater increase in spore formation than the 012 codY mutant. To determine the role of CodY in the observed sporulation phenotypes, we examined several factors that are known to influence sporulation in C. difficile Using transcriptional reporter fusions and quantitative reverse transcription-PCR (qRT-PCR) analysis, we found that two loci associated with the initiation of sporulation, opp and sinR, are regulated by CodY. The data demonstrate that CodY is a repressor of sporulation in C. difficile and that the impact of CodY on sporulation and expression of specific genes is significantly influenced by the strain background. These results suggest that the variability of CodY-dependent regulation is an important contributor to virulence and sporulation in current epidemic isolates. This report provides further evidence that nutritional state, virulence, and sporulation are linked in C. difficile This study sought to examine the relationship between nutrition and sporulation in C. difficile by examining the global nutritional regulator CodY. CodY is a known virulence and nutritional regulator of C. difficile, but its role in sporulation was unknown. Here, we demonstrate that CodY is a negative regulator of sporulation in two different ribotypes of C. difficile We also demonstrate that CodY regulates known effectors of sporulation, Opp and Sin

  9. Combined venomics, venom gland transcriptomics, bioactivities, and antivenomics of two Bothrops jararaca populations from geographic isolated regions within the Brazilian Atlantic rainforest.

    Science.gov (United States)

    Gonçalves-Machado, Larissa; Pla, Davinia; Sanz, Libia; Jorge, Roberta Jeane B; Leitão-De-Araújo, Moema; Alves, Maria Lúcia M; Alvares, Diego Janisch; De Miranda, Joari; Nowatzki, Jenifer; de Morais-Zani, Karen; Fernandes, Wilson; Tanaka-Azevedo, Anita Mitico; Fernández, Julián; Zingali, Russolina B; Gutiérrez, José María; Corrêa-Netto, Carlos; Calvete, Juan J

    2016-03-01

    Bothrops jararaca is a slender and semi-arboreal medically relevant pit viper species endemic to tropical and subtropical forests in southern Brazil, Paraguay, and northern Argentina (Misiones). Within its geographic range, it is often abundant and is an important cause of snakebite. Although no subspecies are currently recognized, geographic analyses have revealed the existence of two well-supported B. jararaca clades that diverged during the Pliocene ~3.8Mya and currently display a southeastern (SE) and a southern (S) Atlantic rainforest (Mata Atlântica) distribution. The spectrum, geographic variability, and ontogenetic changes of the venom proteomes of snakes from these two B. jararaca phylogroups were investigated applying a combined venom gland transcriptomic and venomic analysis. Comparisons of the venom proteomes and transcriptomes of B. jararaca from the SE and S geographic regions revealed notable interpopulational variability that may be due to the different levels of population-specific transcriptional regulation, including, in the case of the southern population, a marked ontogenetic venom compositional change involving the upregulation of the myotoxic PLA2 homolog, bothropstoxin-I. This population-specific marker can be used to estimate the proportion of venom from the southern population present in the B. jararaca venom pool used for the Brazilian soro antibotrópico (SAB) antivenom production. On the other hand, the southeastern population-specific D49-PLA2 molecules, BinTX-I and BinTX-II, lend support to the notion that the mainland ancestor of Bothrops insularis was originated within the same population that gave rise to the current SE B. jararaca phylogroup, and that this insular species endemic to Queimada Grande Island (Brazil) expresses a pedomorphic venom phenotype. Mirroring their compositional divergence, the two geographic B. jararaca venom pools showed distinct bioactivity profiles. However, the SAB antivenom manufactured in Vital Brazil

  10. Determinants of capture-recapture success: an evaluation of trapping methods to estimate population and community parameters for Atlantic forest small mammals

    Directory of Open Access Journals (Sweden)

    Camila S. Barros

    2015-10-01

    Full Text Available ABSTRACT Efficiently obtaining high-quality data on animal populations and communities is paramount for ecological and conservation studies. In many instances these data come from live-trapping, the success of which depends on various factors, such as the interaction between the trap's mechanisms and the morphological or ecological characteristics of the animals, and weather conditions that can affect both trap efficiency and animal behavior. Integrative approaches that address the simultaneous effects of these factors on capture-recapture success are rare. Here we contribute to close this knowledge gap by focusing on a large capture-recapture dataset from three 2-ha grids monitored for approximately two years (totaling 55.000 traps-night in the Morro Grande Forest Reserve, São Paulo, Brazil. The dataset contains data on 3608 captures of 1273 individuals from 24 species of Atlantic forest small mammals. We evaluated if mortality rates and the capture-recapture success of small mammals varied between two types of trap (Sherman and pitfall, and if the capture success of each type varied with age and sex of individuals, and with weather conditions. Our findings highlight that trap efficiency depends not only on the quantities considered (species, individuals or recaptures, but also on animal characteristics and weather conditions. Large pitfall traps should be used whenever the focus is on biodiversity and community parameters, since they captured more individuals and species. Studies focusing on demographic parameters require the combined use of pitfall and Sherman traps. While pitfall traps captured a larger number of individuals and a higher proportion of juveniles, Sherman traps provided higher recapture rates for most species.

  11. Quantifying predation on Baltic cod early life stages

    DEFF Research Database (Denmark)

    Neumann, Viola; Schaber, Matthias; Eero, Margit

    2017-01-01

    Predation on cod (Gadus morhua) eggs by sprat (Sprattus sprattus) and herring (Clupea harengus) is known to be one of the processes influencing reproductive success of the eastern Baltic cod and has been reported to have contributed to lack of recovery of the stock in the 1990s. This study quanti...

  12. Monitoring cod catches of the Dutch demersal fleet in 2016

    NARCIS (Netherlands)

    Hal, van R.; Machiels, M.A.M.

    2017-01-01

    This report presents the results of the cod monitoring program 2016. The research was commissioned by the Dutch Ministry of Economic Affairs within the EZ-program Beleidsondersteunend Onderzoek. Cod catches of the vessels in the fleet segments BT2 (beam trawl and pulse trawl) and TR (otter trawls

  13. Modelling axisymmetric cod-ends made of different mesh types

    DEFF Research Database (Denmark)

    Priour, D.; Herrmann, Bent; O'Neill, F.G.

    2009-01-01

    the selectivity process has become more important. This paper presents a model of the deformation of an axisymmetric cod-end. The twine tension and the catch pressure acting on the knots of each mesh along the cod-end profile are calculated, and a Newton-Raphson scheme is used to estimate the equilibrium position...

  14. The Danish fish fauna during the warm Atlantic period (ca. 7000-3900 bc): Forerunner of future changes?

    DEFF Research Database (Denmark)

    Enghoff, I.B.; MacKenzie, Brian; Eg Nielsen, Einar

    2007-01-01

    Vast amounts of fish bone lie preserved in Denmark's soil as remains of prehistoric fishing. Fishing was particularly important during the Atlantic period (ca. 7000-3900 bc, i.e. part of the Mesolithic Stone Age). At this time, sea temperature and salinity were higher in waters around Denmark than...... today. Analyses of more than 100,000 fish bones from various settlements from this period document which fish species were common in coastal Danish waters at this time. This study provides a basis for comparing the fish fauna in the warm Stone Age sea with the tendencies seen and predicted today...... frequently caught species in the Danish Stone Age sea. These results demonstrate that major changes to the fish fauna near Denmark will occur as climate changes. However, exploitable cod populations can potentially be maintained in waters near Denmark, including the North Sea, but the vulnerability...

  15. The eastern Baltic cod fishery: a fleet-based management strategy evaluation framework to assess the cod recovery plan of 2008

    DEFF Research Database (Denmark)

    Bastardie, Francois; Nielsen, J. Rasmus; Kraus, Gerd

    2010-01-01

    The eastern Baltic cod fishery: a fleet-based management strategy evaluation framework to assess the cod recovery plan of 2008. - ICES Journal of Marine Science, 67: 71-86.......The eastern Baltic cod fishery: a fleet-based management strategy evaluation framework to assess the cod recovery plan of 2008. - ICES Journal of Marine Science, 67: 71-86....

  16. Exploring the Effect of Phage Therapy in Preventing Vibrio anguillarum Infections in Cod and Turbot Larvae

    DEFF Research Database (Denmark)

    Rørbo, Nanna; Rønneseth, Anita; Kalatzis, Panos G.

    2018-01-01

    The aquaculture industry is suffering from losses associated with bacterial infections by opportunistic pathogens. Vibrio anguillarum is one of the most important pathogens, causing vibriosis in fish and shellfish cultures leading to high mortalities and economic losses. Bacterial resistance to a...... KVP40, demonstrating that the phage could also reduce mortality imposed by the background population of pathogens. Overall, phage-mediated reduction in mortality of cod and turbot larvae in experimental challenge assays with V. anguillarum pathogens suggested that application of broad...

  17. Does DNA extraction affect the physical and chemical composition of historical cod (Gadus morhua) otoliths?

    DEFF Research Database (Denmark)

    Therkildsen, Nina Overgaard; Eg Nielsen, Einar; Hüssy, Karin

    2010-01-01

    Archived otoliths constitute an important source of historical DNA for use in temporal genetic studies, but such otoliths are also valuable for other research applications, e.g. growth or microchemistry studies, where information about the past is of relevance. Consequently, there are potentially...... conflicting interests regarding how the limited and irreplaceable otolith collections should be used. To resolve this, it is important to find out whether DNA extraction damages otoliths such that they can no longer be used for other research purposes or whether individual otoliths can be used in multiple...... applications. We examined the effects of three different DNA extraction methods on the elemental composition, the morphology, and the clarity of annual growth increments for successful age estimation of Atlantic cod (Gadus morhua) otoliths that had been archived for 0–31 years. The three extraction methods...

  18. Integrating Archival Tag Data and a High-Resolution Oceanographic Model to Estimate Basking Shark (Cetorhinus maximus Movements in the Western Atlantic

    Directory of Open Access Journals (Sweden)

    Camrin D. Braun

    2018-02-01

    Full Text Available Basking shark (Cetorhinus maximus populations are considered “vulnerable” globally and “endangered” in the northeast Atlantic by the International Union for the Conservation of Nature (IUCN. Much of our knowledge of this species comes from surface observations in coastal waters, yet recent evidence suggests the majority of their lives may be spent in the deep ocean. Depth preferences of basking sharks have significantly limited movement studies that used pop-up satellite archival transmitting (PSAT tags as conventional light-based geolocation is impossible for tagged animals that spend significant time below the photic zone. We tagged 57 basking sharks with PSAT tags in the NW Atlantic from 2004 to 2011. Many individuals spent several months at meso- and bathy-pelagic depths where accurate light-level geolocation was impossible during fall, winter and spring. We applied a newly-developed geolocation approach for the PSAT data by comparing three-dimensional depth-temperature profile data recorded by the tags to modeled in situ oceanographic data from the high-resolution HYbrid Coordinate Ocean Model (HYCOM. Observation-based likelihoods were leveraged within a state-space hidden Markov model (HMM. The combined tracks revealed that basking sharks moved from waters around Cape Cod, MA to as far as the SE coast of Brazil (20°S, a total distance of over 17,000 km. Moreover, 59% of tagged individuals with sufficient deployment durations (>250 days demonstrated seasonal fidelity to Cape Cod and the Gulf of Maine, with one individual returning to within 60 km of its tagging location 1 year later. Tagged sharks spent most of their time at epipelagic depths during summer months around Cape Cod and in the Gulf of Maine. During winter months, sharks spent extended periods at depths of at least 600 m while moving south to the Sargasso Sea, the Caribbean Sea, or the western tropical Atlantic. Our work demonstrates the utility of applying advances in

  19. Interacting trophic forcing and the population dynamics of herring

    DEFF Research Database (Denmark)

    Lindegren, Martin; Ostman, Orjan; Gardmark, Anna

    2011-01-01

    -up nor top-down, but rather through multiple external and internal drivers. While in many studies single drivers have been identified, potential synergies of multiple factors, as well as their relative importance in regulating population dynamics of small pelagic fish, is a largely unresolved issue....... Using a statistical, age-structured modeling approach, we demonstrate the relative importance and influence of bottom-up (e.g., climate, zooplankton availability) and top-down (i.e., fishing and predation) factors on the population dynamics of Bothnian Sea herring (Clupea harengus) throughout its life...... cycle. Our results indicate significant bottom-up effects of zooplankton and interspecific competition from sprat (Sprattus sprattus), particularly on younger age classes of herring. Although top-down forcing through fishing and predation by grey seals (Halichoerus grypus) and Atlantic cod (Gadus morhua...

  20. Improving the size- and species selectivity of cod (Gadus morhua) in demersal mixed-species trawl fisheries

    DEFF Research Database (Denmark)

    Krag, Ludvig Ahm

    reduce the catch of cod without simultaneously reduce the catch of the target species. To optimise the trade-off between discard and loss of marketable catch, solutions have to be specific to particular fisheries or populations of fish. Papers 1 and 3 provide specific examples of how size- and species...

  1. Identifying eastern Baltic cod nursery grounds using hydrodynamic modelling: knowledge for the design of Marine Protected Areas

    DEFF Research Database (Denmark)

    Hinrichsen, Hans-Harald; Kraus, Gerd; Böttcher, Uwe

    2009-01-01

    Knowledge of the spatial and temporal distribution of juvenile cod is essential to closing the life cycle in population dynamic models, and it is a prerequisite for the design of Marine Protected Areas (MPAs) aiming at the protection of juveniles. In this study, we use a hydrodynamic model to exa...

  2. A model-based evaluation of Marine Protected Areas: the example of eastern Baltic cod (Gadus morhua callarias L.)

    DEFF Research Database (Denmark)

    Kraus, Gerd; Pelletier, Dominique; Dubreuil, Julien

    2009-01-01

    The eastern Baltic cod stock collapsed as a consequence of climate-driven adverse hydrographic conditions and over fishing and has remained at historically low levels. Spatio-temporal fishing closures [Marine Protected Areas (MPAs)] have been implemented since 1995, to protect and restore......, combining an age-structured population module with a multifleet exploitation module and a management module in a single model environment. The model is parameterized based on (i) the large amount of biological knowledge available for cod and (ii) an analysis of existing spatially disaggregated fishery data...

  3. Distribution, population biology, and trophic ecology of the deepwater demersal fish Halosauropsis macrochir (Pisces: Halosauridae on the mid-Atlantic Ridge.

    Directory of Open Access Journals (Sweden)

    Odd Aksel Bergstad

    Full Text Available Halosauropsis macrochir ranked amongst the most abundant and widespread demersal fishes on the mid-Atlantic Ridge of the North Atlantic (Iceland-Azores with greatest abundance at 1700-3500 m. All sizes, ranging from 10-76 cm total length, occurred in the area without any apparent spatial pattern or depth trend. Using otolith sections displaying growth increments assumed to represent annuli, the age range recorded was 2-36 years, but most individuals were <20 years. Length and weight at age data were used to fit growth models. No differences between sexes in length and weight at age were observed. The majority of samples had a surplus of males. Diet analysis showed that H. macrochir feeds on Crustacea, Teleostei, Polychaeta, and Cephalopoda, but few prey could be identified to lower taxonomical levels. The mid-Atlantic Ridge constitutes a major portion of the North Atlantic living space of the abyssal halosaur where it completes its full life cycle, primarily as an actively foraging euryophagous micronekton/epibenthos and infauna feeder, becoming a partial piscivore with increasing size.

  4. Dietary variation within and between populations of northeast Atlantic killer whales Orcinus orca, inferred from δ13C and δ15N analyses

    DEFF Research Database (Denmark)

    Foote, Andrew David; Vester, Heike; Vikingsson, Gísli A.

    2012-01-01

    Epidermal skin samples from eastern North Atlantic killer whales, Orcinus orca, were analyzed for carbon and nitrogen stable isotope ratios. From those, compar- isons within a data set of 17 samples collected from Tysfjord, Norway, in November suggested that diet is relatively specialized during...

  5. "XANSONS for COD": a new small BOINC project in crystallography

    Science.gov (United States)

    Neverov, Vladislav S.; Khrapov, Nikolay P.

    2018-04-01

    "XANSONS for COD" (http://xansons4cod.com) is a new BOINC project aimed at creating the open-access database of simulated x-ray and neutron powder diffraction patterns for nanocrystalline phase of materials from the collection of the Crystallography Open Database (COD). The project uses original open-source software XaNSoNS to simulate diffraction patterns on CPU and GPU. This paper describes the scientific problem this project solves, the project's internal structure, its operation principles and organization of the final database.

  6. Historical ecology provides new insights for ecosystem management: Eastern Baltic cod case study

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Ojaveer, Henn; Eero, Margit

    2011-01-01

    A recent historical marine ecological case study (cod in the eastern Baltic Sea) is used to show how long-term data and knowledge of fluctuations can contribute to revisions of fishery management policy. The case study first developed new longer analytical time series of spawner biomass and recru......A recent historical marine ecological case study (cod in the eastern Baltic Sea) is used to show how long-term data and knowledge of fluctuations can contribute to revisions of fishery management policy. The case study first developed new longer analytical time series of spawner biomass...... catch data from the late 1500s to early 1600s also contributed new perspectives to cod population dynamics under alternative ecosystem forcings. These new perspectives have contributed, and will likely continue to contribute to new management policies (e.g., revision of fishery management reference...... points), which should lead to higher sustainability of the population and fishery yields, and improved overall ecosystem health. These perspectives will likely continue to provide baseline information as ICES and the EU develop new policies based on maximum sustainable yield concepts....

  7. The COD Model: Simulating Workgroup Performance

    Science.gov (United States)

    Biggiero, Lucio; Sevi, Enrico

    Though the question of the determinants of workgroup performance is one of the most central in organization science, precise theoretical frameworks and formal demonstrations are still missing. In order to fill in this gap the COD agent-based simulation model is here presented and used to study the effects of task interdependence and bounded rationality on workgroup performance. The first relevant finding is an algorithmic demonstration of the ordering of interdependencies in terms of complexity, showing that the parallel mode is the most simplex, followed by the sequential and then by the reciprocal. This result is far from being new in organization science, but what is remarkable is that now it has the strength of an algorithmic demonstration instead of being based on the authoritativeness of some scholar or on some episodic empirical finding. The second important result is that the progressive introduction of realistic limits to agents' rationality dramatically reduces workgroup performance and addresses to a rather interesting result: when agents' rationality is severely bounded simple norms work better than complex norms. The third main finding is that when the complexity of interdependence is high, then the appropriate coordination mechanism is agents' direct and active collaboration, which means teamwork.

  8. Male reproductive competition in spawning aggregations of cod ( Gadus morhua , L.)

    DEFF Research Database (Denmark)

    Bekkevold, Dorte; Hansen, Michael Møller; Loeschcke, V.

    2002-01-01

    Reproductive competition may lead to a large skew in reproductive success among individuals. Very few studies have analysed the paternity contribution of individual males in spawning aggregations of fish species with huge census population sizes. We quantified the variance in male reproductive...... success in spawning aggregations of cod under experimental conditions over an entire spawning season. Male reproductive success was estimated by microsatellite-based parentage analysis of offspring produced in six separate groups of spawning cod. In total, 1340 offspring and 102 spawnings distributed...... across a spawning season were analysed. Our results show that multiple males contributed sperm to most spawnings but that paternity frequencies were highly skewed among males, with larger males on average siring higher proportions of offspring. It was further indicated that male reproductive success...

  9. COD correction for laser cooling at S-LSR

    International Nuclear Information System (INIS)

    Souda, Hikaru; Fujimoto, Shinji; Tongu, Hiromu; Shirai, Toshiyuki; Tanabe, Mikio; Ishikawa, Takehiro; Nakao, Masao; Ikegami, Masahiro; Wakita, Akihisa; Iwata, Soma; Fujimoto, Tetsuya; Takeuchi, Takeshi; Noda, Koji; Noda, Akira

    2008-01-01

    A closed orbit is corrected for single-turn injection to perform laser cooling experiments of 40 keV 24 Mg + beam at the small laser-equipped storage ring (S-LSR). Closed orbit distortion (COD) corrections have been carried out using a downhill simplex method, and CODs of less than ±0.5mm have been achieved throughout the whole circumference. The injection orbit and the CODs are optimized to pass through the two aperture holes in the alignment targets located in the laser cooling section with an algorithm to maximize beam lifetime. The CODs at the aperture holes are reduced to be less than ±0.2mm, assuring an overlap between the laser and the 24 Mg + ion beam.

  10. Dual annual spawning races in Atlantic sturgeon.

    Directory of Open Access Journals (Sweden)

    Matthew T Balazik

    Full Text Available Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus, Acipenseridae populations in the United States were listed as either endangered or threatened under the Endangered Species Act in 2012. Because of the endangered/threatened status, a better understanding of Atlantic sturgeon life-history behavior and habitat use is important for effective management. It has been widely documented that Atlantic sturgeon reproduction occurs from late winter to early summer, varying clinally with latitude. However, recent data show Atlantic sturgeon also spawn later in the year. The group that spawns later in the year seems to be completely separate from the spring spawning run. Recognition of the later spawning season has drastically modified estimates of the population status of Atlantic sturgeon in Virginia. With the combination of new telemetry data and historical documentation we describe a dual spawning strategy that likely occurs in various degrees along most, if not all, of the Atlantic sturgeon's range. Using new data combined with historical sources, a new spawning strategy emerges which managers and researchers should note when determining the status of Atlantic sturgeon populations and implementing conservation measures.

  11. Simulation-based investigation of the paired-gear method in cod-end selectivity studies

    DEFF Research Database (Denmark)

    Herrmann, Bent; Frandsen, Rikke; Holst, René

    2007-01-01

    In this paper, the paired-gear and covered cod-end methods for estimating the selectivity of trawl cod-ends are compared. A modified version of the cod-end selectivity simulator PRESEMO is used to simulate the data that would be collected from a paired-gear experiment where the test cod-end also ...

  12. De novo genome assembly and annotation of Australia's largest freshwater fish, the Murray cod (Maccullochella peelii), from Illumina and Nanopore sequencing read.

    Science.gov (United States)

    Austin, Christopher M; Tan, Mun Hua; Harrisson, Katherine A; Lee, Yin Peng; Croft, Laurence J; Sunnucks, Paul; Pavlova, Alexandra; Gan, Han Ming

    2017-08-01

    One of the most iconic Australian fish is the Murray cod, Maccullochella peelii (Mitchell 1838), a freshwater species that can grow to ∼1.8 metres in length and live to age ≥48 years. The Murray cod is of a conservation concern as a result of strong population contractions, but it is also popular for recreational fishing and is of growing aquaculture interest. In this study, we report the whole genome sequence of the Murray cod to support ongoing population genetics, conservation, and management research, as well as to better understand the evolutionary ecology and history of the species. A draft Murray cod genome of 633 Mbp (N50 = 109 974bp; BUSCO and CEGMA completeness of 94.2% and 91.9%, respectively) with an estimated 148 Mbp of putative repetitive sequences was assembled from the combined sequencing data of 2 fish individuals with an identical maternal lineage; 47.2 Gb of Illumina HiSeq data and 804 Mb of Nanopore data were generated from the first individual while 23.2 Gb of Illumina MiSeq data were generated from the second individual. The inclusion of Nanopore reads for scaffolding followed by subsequent gap-closing using Illumina data led to a 29% reduction in the number of scaffolds and a 55% and 54% increase in the scaffold and contig N50, respectively. We also report the first transcriptome of Murray cod that was subsequently used to annotate the Murray cod genome, leading to the identification of 26 539 protein-coding genes. We present the whole genome of the Murray cod and anticipate this will be a catalyst for a range of genetic, genomic, and phylogenetic studies of the Murray cod and more generally other fish species of the Percichthydae family. © The Authors 2017. Published by Oxford University Press.

  13. Population structure and reproduction of Deuterodon langei travassos, 1957 (Teleostei, Characidae in a neotropical stream basin from the Atlantic Forest, Southern Brazil

    Directory of Open Access Journals (Sweden)

    Jean Ricardo Simões Vitule

    2008-12-01

    Full Text Available Aspects of the biology of D. langei were studied at different sites along a longitudinal gradient formed by the Ribeirão stream basin, a Neotropical stream of the Atlantic Forest, southern Brazil. Differences were observed in population structure and reproduction along the longitudinal gradient and during the study period. Juvenile fishes occurred in high abundance, mainly in the downstream site after the rainy months. Adults occurred mainly in the intermediate and upstream sites. During their life cycle, adults optimise their reproductive strategy by concentrating the reproductive period with total spawn in a short time interval before summer rains dragged the juvenile, larval forms and/or eggs downstream. The downstream site was characterized by a wide range of microhabitats (ex. submerged grass and shallow flooded area. Thus, the species used different portions of the basin in distinct stages of its life, being ecologically adapted to variation patterns in its temporal and physical environments.Aspectos da biologia de D. langei foram estudados em diferentes locais da bacia do rio Ribeirão, um riacho litorâneo da Floresta Atlântica do sudeste do Brasil. Foram observadas diferenças na estrutura da população e na reprodução, ao longo do gradiente longitudinal da bacia e do período de estudo. Os peixes juvenis ocorreram em grande abundância, principalmente no trecho a jusante da bacia, após os meses mais chuvosos. Adultos ocorreram principalmente nos trechos intermediários e a montante. Não houve diferença significativa na relação sexual entre os locais amostrados, estações do ano, meses e classes de comprimento. O comprimento médio de primeira maturação (L50 foi o mesmo para machos e fêmeas, entre 6,1 e 7,0 cm de comprimento total (Lt. O período reprodutivo foi curto (entre o final da primavera e início do verão, antes dos meses mais chuvosos, com desova total. O Índice de Atividade Reprodutiva (IAR indicou que D

  14. 76 FR 2640 - Fisheries of the Northeastern United States; Atlantic Bluefish Fishery; 2011 Atlantic Bluefish...

    Science.gov (United States)

    2011-01-14

    ... Assistant Administrator has determined that this proposed rule is consistent with the Atlantic Bluefish FMP... D. Rauch III, Deputy Assistant Administrator for Regulatory Programs, National Marine Fisheries... mortality; stock status; recent estimates of recruitment; virtual population analysis results; levels of...

  15. 2005 Atlantic Hurricanes Poster

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 2005 Atlantic Hurricanes poster features high quality satellite images of 15 hurricanes which formed in the Atlantic Basin (includes Gulf of Mexico and Caribbean...

  16. Northeast Atlantic blue whiting

    OpenAIRE

    Heino, Mikko

    2010-01-01

    Heino, M. 2010. Northeast Atlantic blue whiting. In Life cycle spatial patterns of small pelagic fish in the Northeast Atlantic, pp. 59-64. Ed by P. Petitgas. ICES Cooperative Research Report 306. ICES, Copenhagen.

  17. Prey exoskeletons influence the course of gastric evacuation in Atlantic cod Gadus morhua

    DEFF Research Database (Denmark)

    Couturier, C. S.; Andersen, N. G.; Audet, C.

    2013-01-01

    species, Pandalus borealis, Pandalus montagui and Eualus macilentus, and the crab Chionoecetes opilio, were evacuated from the stomach at different rates. The duration of all stages increased with increasing ash (and carbonate) content of the fresh prey. Thickness, chemical composition and morphology...... of the prey exoskeleton all affected gastric evacuation: duration of initial delay, overall evacuation rate and a decreased evacuation rate at the end of the process. The power exponential function (PEF), with its shape parameter, described the course of evacuation for these prey types well, especially...

  18. The use of otolith microstructure to estimate age in adult Atlantic cod Gadus morhua

    DEFF Research Database (Denmark)

    Hüssy, Karin; Hinrichsen, H.H.; Fey, D.P.

    2010-01-01

    a distinct pattern with increasing distance from the primary primordium. A series of zones with clearly distinguishable increments, first with increasing then with decreasing widths in a dome-shaped pattern, were separated by zones where no regular increment structure was visible. Increment width seemed...... to be tightly coupled to the annual cycle in environmental temperature at a depth of 30–60 m, where G. morhua predominantly reside. Between 135 and 200 increments occurred within the different zones, with a non-significant trend towards lower increment numbers and widths with distance from the primary...... primordium of the otolith. Increment formation apparently ceased at temperatures C, but growth during the cold months corresponded closely with estimated growth rates. The increment patterns seemed to reflect annual cycles in environmental temperature, and the count of the increment cycles may thus...

  19. Fathers modify thermal reaction norms for hatching success in Atlantic cod, Gadus morhua

    DEFF Research Database (Denmark)

    Dahlke, Flemming T.; Politis, Sebastian Nikitas; Butts, Ian

    2016-01-01

    hatching success significantly decreased towards thermal extremes. However, half-sibling families varied in their response to different incubation temperatures as indicated by significant paternity × temperature interactions and crossing of reaction norms. The influence of paternity itself was highly...... survival among half-sibling families and temperature treatments was observed during blastula and gastrulation stages (until 100% epiboly), while almost no mortality occurred during subsequent development and throughout the hatching period. The observed magnitude of genetic variation underlying thermal...

  20. Temperature, paternity and asynchronous hatching influence early developmental characteristics of larval Atlantic cod, Gadus morhua

    DEFF Research Database (Denmark)

    Politis, Sebastian Nikitas; Dahlke, Flemming T.; Butts, Ian A.E.

    2014-01-01

    Offspring, especially during early development, are influenced by both intrinsic properties endowed to them by their parents, extrinsic environmental factors as well as the interplay between genes and the environment. We investigated the effects of paternity (P), temperature (T), and asynchronous...

  1. Paternal effects on early life history traits in Northwest Atlantic cod, Gadus morhua

    DEFF Research Database (Denmark)

    Kroll, M.-M.; Peck, M.A.; Butts, Ian A.E.

    2013-01-01

    It is important to understand parental effects on early life history of fish as manifested, for example, in individual fitness of offspring. Immediately after fertilization, parental contributions (both genetic and non-genetic) to embryos will affect larval ontogeny, physiology, morphology...... and survival. In marine fish, rates of natural mortality are highest during early life and are negatively correlated with rates of growth and body size. In these early life stages (eggs, larvae, young juveniles) subtle differences in mortality can cause large differences in recruitment and year-class success...... and can serve as important sources of variation during early life stages in fishes. Overall, these findings have implications for furthering the understanding of recruitment variability and can be used to optimize reproductive output for the aquaculture industry. In addition, the data suggests...

  2. Social sustainability of cod and haddock fisheries in the northeast Atlantic: what issues are important?

    NARCIS (Netherlands)

    Veldhuizen, L.J.L.; Berentsen, P.; Bokkers, E.A.M.; Boer, de I.J.M.

    2015-01-01

    Research on the sustainability of capture fisheries has focused more on environmental and economic sustainability than on social sustainability. To assess social sustainability, first relevant and important social sustainability issues need to be identified. The objective of this study was to

  3. The effects of pre-salting methods on salt and water distribution of heavily salted cod, as analyzed by 1H and 23Na MRI, 23Na NMR, low-field NMR and physicochemical analysis

    DEFF Research Database (Denmark)

    Guðjónsdóttir, María; Traoré, Amidou; Jónsson, Ásbjörn

    2015-01-01

    The effect of different pre-salting methods (brine injection with salt with/without polyphosphates, brining and pickling) on the water and salt distribution in dry salted Atlantic cod (Gadus morhua) fillets was studied with proton and sodium NMR and MRI methods, supported by physicochemical analy...

  4. COD removal characteristics in air-cathode microbial fuel cells

    KAUST Repository

    Zhang, Xiaoyuan

    2015-01-01

    © 2014 Elsevier Ltd. Exoelectrogenic microorganisms in microbial fuel cells (MFCs) compete with other microorganisms for substrate. In order to understand how this affects removal rates, current generation, and coulombic efficiencies (CEs), substrate removal rates were compared in MFCs fed a single, readily biodegradable compound (acetate) or domestic wastewater (WW). Removal rates based on initial test conditions fit first-order kinetics, but rate constants varied with circuit resistance. With filtered WW (100Ω), the rate constant was 0.18h- 1, which was higher than acetate or filtered WW with an open circuit (0.10h- 1), but CEs were much lower (15-24%) than acetate. With raw WW (100Ω), COD removal proceeded in two stages: a fast removal stage with high current production, followed by a slower removal with little current. While using MFCs increased COD removal rate due to current generation, secondary processes will be needed to reduce COD to levels suitable for discharge.

  5. Using alternative biological information in stock assessment: condition-corrected natural mortality of Eastern Baltic cod

    DEFF Research Database (Denmark)

    Casini, Michele; Eero, Margit; Carlshamre, Sofia

    2016-01-01

    ) assumed in the analytical stock assessment model. The results in terms of Spawning Stock Biomass (SSB), Fishing mortality (F) and Recruitment (R) in the final year from the stock assessment using M values adjusted for low condition were up to 40% different compared with the assessment assuming a constant......The inclusion of biological and ecological aspects in the assessment of fish population status is one of the bases for an ecosystem-based fisheries management. During the past two decades the Eastern Baltic cod has experienced a drastic reduction in growth and body condition that may have affected...

  6. CodY-mediated regulation of Streptococcus pyogenes exoproteins

    Directory of Open Access Journals (Sweden)

    McDowell Emily J

    2012-06-01

    Full Text Available Abstract Background The production of Streptococcus pyogenes exoproteins, many of which contribute to virulence, is regulated in response to nutrient availability. CodY is a transcriptional regulator that controls gene expression in response to amino acid availability. The purpose of this study was to identify differences in the expression of streptococcal exoproteins associated with deletion of the codY gene. Results We compared the secreted proteins produced by wild-type S. pyogenes to a codY mutant in the post-exponential phase of growth. We used both one and two-dimensional gel electrophoresis to separate exoproteins. Proteins that were significantly different in abundance upon repeated analysis were identified with tandem mass spectrometry. The production of the secreted cysteine protease SpeB, a secreted chromosomally encoded nuclease (SdaB, and a putative adhesion factor (Spy49_0549 were more abundant in supernatant fluids obtained from the codY mutant. In addition, hyaluronidase (HylA, CAMP factor (Cfa, a prophage encoded nuclease (Spd-3, and an uncharacterized extracellular protein (Spy49_0015 were less abundant in supernatant fluids obtained from the codY mutant strain. Enzymatic assays showed greater DNase activity in culture supernatants isolated in the post-exponential phase of growth from the codY mutant strain compared to the wild-type strain. Because extracellular nucleases and proteases can influence biofilm formation, we also measured the ability of the strains to form biofilms during growth with both rich medium (Todd Hewitt yeast extract; THY and chemically defined media (CDM. No difference was observed with rich media but with CDM the biofilms formed by the codY mutant strain had less biomass compared to the wild-type strain. Conclusions Overall, the results indicate that CodY alters the abundance of a select group of S. pyogenes exoproteins, including DNases, a protease, and hylauronidase, which together may alleviate

  7. Groundfish overfishing, diatom decline, and the marine silica cycle: Lessons from Saanich Inlet, Canada, and the Baltic Sea cod crash

    Science.gov (United States)

    Katz, Timor; Yahel, Gitai; Yahel, Ruthy; Tunnicliffe, Verena; Herut, Barak; Snelgrove, Paul; Crusius, John; Lazar, Boaz

    2009-12-01

    In this study, we link groundfish activity to the marine silica cycle and suggest that the drastic mid-1980s crash of the Baltic Sea cod (Gadus morhua) population triggered a cascade of events leading to decrease in dissolved silica (DSi) and diatom abundance in the water. We suggest that this seemingly unrelated sequence of events was caused by a marked decline in sediment resuspension associated with reduced groundfish activity resulting from the cod crash. In a study in Saanich Inlet, British Columbia, Canada, we discovered that, by resuspending bottom sediments, groundfish triple DSi fluxes from the sediments and reduce silica accumulation therein. Using these findings and the available oceanographic and environmental data from the Baltic Sea, we estimate that overfishing and recruitment failure of Baltic cod reduced by 20% the DSi supply from bottom sediments to the surface water leading to a decline in the diatom population in the Baltic Sea. The major importance of the marginal ocean in the marine silica cycle and the associated high population density of groundfish suggest that groundfish play a major role in the silica cycle. We postulate that dwindling groundfish populations caused by anthropogenic perturbations, e.g., overfishing and bottom water anoxia, may cause shifts in marine phytoplankton communities.

  8. Causes and projections of abrupt climate-driven ecosystem shifts in the North Atlantic

    DEFF Research Database (Denmark)

    Beaugrand, G.; Edwards, M.; Brander, Keith

    2008-01-01

    Warming of the global climate is now unequivocal and its impact on Earth' functional units has become more apparent. Here, we show that marine ecosystems are not equally sensitive to climate change and reveal a critical thermal boundary where a small increase in temperature triggers abrupt...... ecosystem shifts seen across multiple trophic levels. This large-scale boundary is located in regions where abrupt ecosystem shifts have been reported in the North Atlantic sector and thereby allows us to link these shifts by a global common phenomenon. We show that these changes alter the biodiversity...... and carrying capacity of ecosystems and may, combined with fishing, precipitate the reduction of some stocks of Atlantic cod already severely impacted by exploitation. These findings offer a way to anticipate major ecosystem changes and to propose adaptive strategies for marine exploited resources such as cod...

  9. Chemical oxygen demand (cod) attenuation of methyl red in water ...

    African Journals Online (AJOL)

    Chemical oxygen demand (cod) attenuation of methyl red in water using biocarbons obtained from Nipa palm leaves. ... eco-friendly and locally accessible biocarbon for mitigation of organic contaminants in water. Keywords: Chemical oxygen demand, biocarbon, methyl red, biodegradation, bioremediation, Nipa palm ...

  10. Arctic Climate Change: A Tale of Two Cod Species

    Science.gov (United States)

    Arctic cod play an important role in the Arctic trophic hierarchy as the consumer of primary productivity and a food source for many marine fish and mammals. Shifts in their distribution and abundance could have cascading affects in the marine environment. This paper investigates...

  11. Removal of hard COD, nitrogenous compounds and phenols from a ...

    African Journals Online (AJOL)

    The objective of this study was to identify the factors affecting the suspended and fixed biomass in the removal of hard COD, nitrogenous compounds and phenols from a coal gasification wastewater (CGWW) stream using a hybrid fixed-film bioreactor (H-FFBR) process under real-time plant operational conditions and ...

  12. Review of western Baltic cod (Gadus morhua) recruitment dynamics

    DEFF Research Database (Denmark)

    Hüssy, Karin

    2011-01-01

    Important processes in the recruitment dynamics of western Baltic cod (Gadus morhua) are identified. Spawning areas are in the deep, saline waters below 20–40 m, depending on area topography. Spatial distribution remains relatively stable over time. Peak spawning shows an area-specific pattern...

  13. Eastern Baltic cod recruitment revisited—dynamics and impacting factors

    DEFF Research Database (Denmark)

    Köster, Fritz; Huwer, Bastian; Hinrichsen, Hans-Harald

    2017-01-01

    The Eastern Baltic cod abundance started rapidly to increase in the mid-2000s as evidenced by analytical stock assessments, due to increased recruitment and declining fishing mortality. Since 2014, the analytical stock assessment is not available, leaving the present stock status unclear and cast......The Eastern Baltic cod abundance started rapidly to increase in the mid-2000s as evidenced by analytical stock assessments, due to increased recruitment and declining fishing mortality. Since 2014, the analytical stock assessment is not available, leaving the present stock status unclear...... and casting doubts about the magnitude of the recent increase in recruitment. Earlier studies identified main factors impacting on cod reproductive success to be related to the loss of two out of three spawning areas in the 1980s caused by lack of major Baltic inflows with a concurrent reduction in salinity...... decade, as the period was characterized by an absence of large-scale Baltic inflows since 2003 and persistent anoxic conditions in the bottom water of the deep Baltic basins. This questions the perception of the increased recruitment in later years and challenges our present understanding of cod...

  14. Fluorescence of muscle and connective tissue from cod and salmon

    DEFF Research Database (Denmark)

    Andersen, Charlotte Møller; Wold, J.P.

    2003-01-01

    Autofluorescence of salmon and cod muscle was measured and compared with autofluorescence of collagen type I and type V. Similarities between fluorescence of fish muscle and collagen were found in that the same peaks were obtained around 390, 430, and 480 nm, These similarities are supported...

  15. Rearing Water Treatment Induces Microbial Selection Influencing the Microbiota and Pathogen Associated Transcripts of Cod (Gadus morhua Larvae

    Directory of Open Access Journals (Sweden)

    Ragnhild I. Vestrum

    2018-05-01

    Full Text Available We have previously shown that K-selection and microbial stability in the rearing water increases survival and growth of Atlantic cod (Gadus morhua larvae, and that recirculating aquaculture systems (RAS are compatible with this. Here, we have assessed how water treatment influenced the larval microbiota and host responses at the gene expression level. Cod larvae were reared with two different rearing water systems: a RAS and a flow-through system (FTS. The water microbiota was examined using a 16S rDNA PCR/DGGE strategy. RNA extracted from larvae at 8, 13, and 17 days post hatching was used for microbiota and microarray gene expression analysis. Bacterial cDNA was synthesized and used for 16S rRNA amplicon 454 pyrosequencing of larval microbiota. Both water and larval microbiota differed significantly between the systems, and the larval microbiota appeared to become more dissimilar between systems with time. In total 4 phyla were identified for all larvae: Actinobacteria, Bacteroidetes, Firmicutes, and Proteobacteria. The most profound difference in larval microbiota was a high abundance of Arcobacter (Epsilonproteobacteria in FTS larvae (34 ± 9% of total reads. Arcobacter includes several species that are known pathogens for humans and animals. Cod larval transcriptome responses were investigated using an oligonucleotide gene expression microarray covering approximately 24,000 genes. Interestingly, FTS larvae transcriptional profiles revealed an overrepresentation of upregulated transcripts associated with responses to pathogens and infections, such as c1ql3-like, pglyrp-2-like and zg16, compared to RAS larvae. In conclusion, distinct water treatment systems induced differences in the larval microbiota. FTS larvae showed up-regulation of transcripts associated with responses to microbial stress. These results are consistent with the hypothesis that RAS promotes K-selection and microbial stability by maintaining a microbial load close to the

  16. Externally driven mortality of cod early life stages in the central Baltic: hydrography vs. predation

    DEFF Research Database (Denmark)

    Neumann, Viola; Köster, Fritz; Schaber, Matthias

    pressure by clupeids on the early life stages of cod could have enhanced cod recruitment in recent years. The analyses are based on a large dataset of stomach content of clupeids, cod egg abundances from ichthyoplankton surveys, and hydrographic measurements. We investigate temporal and spatial variability...

  17. Estimation of bacterial quality of cod fillets with the disc flotation method

    International Nuclear Information System (INIS)

    Boismenu, D.; Lepine, F.; Thibault, C.; Gagnon, M.; Charbonneau, R.; Dugas, H.

    1991-01-01

    Spoilage bacteria of cod fillets were desorbed off the fillet surface by ultrasonication. Catalase activity of these bacteria was determined using the disc flotation method after selective heat inactivation of the endogenous cod catalase and then correlated with the colony forming units. The method was applied to cod fillets from ten retail sources with satisfactory results

  18. Fishing cod in the Baltic Sea - Gambling with the ecosystem services

    Science.gov (United States)

    Björkman, Sven; Nordlöf, Anders

    2014-05-01

    The population of cod in the Baltic sea has over the last decades decreased due to overfishing. To make the students aware of this problem and also to find a solution they are introduced to a game. The purpose of the game is to let the students know how to use renewable natural resources in these aspects; 1 Fishing cod without using it up 2 That solidarity is needed if you are sharing a resource 3 That cooperation is the key to keeping a natural resource healthy. The students are fishermen in group of four and are equipped with a boat. The playing board is a map over the Baltic sea. The rules of the game include the carrying capacity of the sea, how much fish one fishing boat is allowed to pick up, how much it costs to have a boat, and possibilities to buy a bigger boat. The game has two rounds: In round one the students in the group are competing against each other, they are not allowed to talk to each other and they are supposed to get as much fish as they can. As a consequence after round one the sea will become empty. In round two the groups compete with each other and they are coworking within the group. After this round the result is different from the first round. The catches are bigger than in round one and still there are cod left in the sea, which will generate a good fishing in the future.. The discussions after the game can be about why the two rounds ended so different, general discussion about "tragedy of the commons", sustainable use of ecosystem services and discussions about resources in common.

  19. Extrusion of Contracaecum osculatum nematode larvae from the liver of cod (Gadus morhua).

    Science.gov (United States)

    Zuo, S; Barlaup, L; Mohammadkarami, A; Al-Jubury, A; Chen, D; Kania, P W; Buchmann, K

    2017-10-01

    Baltic cod livers have during recent years been found increasingly and heavily infected with third-stage larvae of Contracaecum osculatum. The infections are associated with an increasing population of grey seals which are final hosts for the parasite. Heavy worm burdens challenge utilization and safety of the fish liver products, and technological solutions for removal of worms are highly needed. We investigated the attachment of the worm larvae in liver tissue by use of histochemical techniques and found that the cod host encapsulates the worm larvae in layers of host cells (macrophages, fibroblasts) supported by enclosures of collagen and calcium. A series of incubation techniques, applying compounds targeting molecules in the capsule, were then tested for their effect to induce worm escape/release reactions. Full digestion solutions comprising pepsin, NaCl, HCl and water induced a fast escape of more than 60% of the worm larvae within 20 min and gave full release within 65 min but the liver tissue became highly dispersed. HCl alone, in concentrations of 48 and 72 mM, triggered a corresponding release of worm larvae with minor effect on liver integrity. A lower HCl concentration of 24 mM resulted in 80% release within 35 min. Water and physiological saline had no effect on worm release, and 1% pepsin in water elicited merely a weak escape reaction. In addition to the direct effect of acid on worm behaviour it is hypothesised that the acid effect on calcium carbonate in the encapsulation, with subsequent release of reaction products, may contribute to activation of C. osculatum larvae and induce escape reactions. Short-term pretreatment of infected cod liver and possibly other infected fish products, using low acid concentrations is suggested as part of a technological solution for worm clearance as low acid concentrations had limited macroscopic effect on liver integrity within 35 min.

  20. Detecting population structure in a high gene-flow species, Atlantic herring (Clupea harengus): direct, simultaneous evaluation of neutral vs putatively selected loci

    DEFF Research Database (Denmark)

    André, C.; Larsson, L. C.; Laikre, L.

    2010-01-01

    In many marine fish species, genetic population structure is typically weak because populations are large, evolutionarily young and have a high potential for gene flow. We tested whether genetic markers influenced by natural selection are more efficient than the presumed neutral genetic markers t...

  1. Genetic variation and local differences in Pacific cod Gadus macrocephalus around Japan.

    Science.gov (United States)

    Suda, A; Nagata, N; Sato, A; Narimatsu, Y; Nadiatul, H H; Kawata, M

    2017-01-01

    The population structure of the Pacific cod Gadus macrocephalus was examined using 15 microsatellite loci and mitochondrial DNA (ND2 region). In total, 274 individuals were sampled from 16 locations around Japan to estimate the level of genetic differentiation and effective population size (N e ). Pairwise F ST , analysis of molecular variance and Bayesian clustering analysis suggested the presence of two genetically distinct groups in waters around Japan, with a higher N e value in the eastern group than in the western group. A possible factor that restricts gene flow between groups may be related to the water temperature differences in the south-western part of the Sea of Japan, where the Tsushima Warm Current flows around the area inhabited by the western group, which may limit migration between the west and east. © 2016 The Fisheries Society of the British Isles.

  2. INTRA-AND INTER-POPULATION VARIATION IN SEED SIZE AND DORMANCY IN Schizolobium parahyba (Vell. Blake IN THE ATLANTIC FOREST

    Directory of Open Access Journals (Sweden)

    Juliana Müller Freire

    2015-01-01

    Full Text Available Seed size and dormancy level were studied in 20 trees from two populations of Schizolobium parahybato evaluate how these characteristics occurbetween and within populations, and whether seed germination was affected by its morphometry. These two populations are located in the coastal (Paraty or mountain (Miguel Pereira regions in the state of Rio de Janeiro, Brazil. The seed morphometrictraits (length, width, thickness and weight were measured. Germination with or without seedcoatdormancy treatment (mechanical scarification wasassessedbya randomized emergence test in nursey. All morphometric traits differed significantly among individuals and between populations. The trees from the mountain region showed a larger seed size and a lower dormancy level than that of trees from the coastal region. Seed size had no effect on seed germination or seedling development. Climate influence on the determination of germination behavior is discussed based on the results.

  3. Isolation of putative probionts from cod rearing environment

    DEFF Research Database (Denmark)

    Lauzon, H.L.; Gudmundsdottir, S.; Pedersen, M.H.

    2008-01-01

    , metabolite production and adhesion to fish cell lines. Our study demonstrated that 14% of screened bacteria (n = 188) had antagonistic properties towards fish pathogens. The majority of these isolates were Gram-positive (81%), belonging to Firmicutes (69.2%) and Actinobacteria (11.5%) phyla based on 16S r...... was designed to search for new probiotics to target this critical period in cod rearing. Potential probionts were selected from the naturalmicrobiota of cod aquacultural environment. The selection was based on several criteria: pathogen inhibition potential, growth characteristics, strain identification......RNA gene sequencing. Only 6 (3.2%) of 188 isolates could inhibit all three pathogens tested: Vibrio anguillarum, Aeromonas salmonicida subsp. achromogenes and Vibrio salmonicida. Differences observed in activity intensity and spectrum among inhibitory isolates emphasise the need to develop probiotic...

  4. Ecological forecasting under climate change: the case of Baltic cod

    DEFF Research Database (Denmark)

    Lindegren, Martin; Möllmann, Christian; Nielsen, Anders

    2010-01-01

    Good decision making for fisheries and marine ecosystems requires a capacity to anticipate the consequences of management under different scenarios of climate change. The necessary ecological forecasting calls for ecosystem-based models capable of integrating multiple drivers across trophic levels...... and properly including uncertainty. The methodology presented here assesses the combined impacts of climate and fishing on marine food-web dynamics and provides estimates of the confidence envelope of the forecasts. It is applied to cod (Gadus morhua) in the Baltic Sea, which is vulnerable to climate......-related decline in salinity owing to both direct and indirect effects (i.e. through species interactions) on early-life survival. A stochastic food web-model driven by regional climate scenarios is used to produce quantitative forecasts of cod dynamics in the twenty-first century. The forecasts show how...

  5. Practical application of COD measurement in welded assemblies

    International Nuclear Information System (INIS)

    Beghe, S.

    1975-01-01

    Measurement of the COD makes it possible to evaluate sensitivity to brittle fracture initiation. This technique is ideal for welded structures, owing to the types of defect likely to affect them, and the magnitude of the residual stresses introduced. Moreover, the COD concept, based on thickness and temperature experiments on materials, enables evaluation of the critical defect size in these structures. However, its application to welded joints encounters certain problems. The presence of fatigue cracks in the molten zone of a welded joint is frequently disturbed by the residual stresses caused by welding. An additional difficulty is created by the problem of stable growth of the crack during the bending test. This discussion covers all these matters and suggests some solutions [fr

  6. Stability of compounded trilostane suspension in cod liver oil.

    Science.gov (United States)

    Crosby, Jesse; Brown, Stacy

    2017-10-01

    Trilostane is a synthetic steroid analog used to treat canine hyperadrenocorticism. For small dogs, the dose found in commercially available dosage forms of trilostane is sometimes too high. Compounding trilostane in a liquid diluent provides an option for more precise dosing and adjustments, and can be easier to administer, versus a tablet or capsule. Trilostane suspends well in cod liver oil, which is generally palatable to dogs. The stability of a compounded trilostane suspension in cod liver oil stored at room temperature was investigated for 90 days. Compounded trilostane retained stability, defined as maintaining 90-105% labeled value, for 60 days when stored in amber glass bottles. However, drug potency fell >10% below the labeled value when stored in amber plastic bottles after 7 days. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Episodic Eolian Sand Deposition in the Past 4000 Years in Cape COD National Seashore, Massachusetts, USA in Response to Possible Hurricane/storm and Anthropogenic Disturbances

    Science.gov (United States)

    Forman, Steven

    2015-02-01

    The eolian sand depositional record for a dune field within Cape Cod National Seashore, Massachusetts is posit as a sensitive indicator of environmental disturbances in the late Holocene from a combination of factors such as hurricane/storm and forest fire occurrence, and anthropogenic activity. Stratigraphic and sedimentologic observations, particularly the burial of spodosol-like soils, and associated 14C and OSL ages that are concordant indicate at least six eolian depositional events at ca. 3750, 2500, 1800, 960, 430 and Atlantic Ocean at ca. 2.0 to 1.6, and 1.0 ka and also a wetter coastal climate, which suppressed the occurrence of forest fire. Thus, local droughts are not associated with periods of dune movement in this mesic environment. Latest eolian activity on outer Cape Cod commenced in the past 300 to 500 years and may reflect multiple factors including broad-scale landscape disturbance with European colonization, an increased incidence of forest fires and heightened storminess. Eolian systems of Cape Cod appear to be sensitive to landscape disturbance and prior to European settlement may reflect predominantly hurricane/storm disturbance, despite generally mesic conditions in past 4 ka.

  8. Detection of Fish Bones in Cod Fillets by UV Illumination.

    Science.gov (United States)

    Wang, Sheng; Nian, Rui; Cao, Limin; Sui, Jianxin; Lin, Hong

    2015-07-01

    The presence of fish bones is now regarded as an important hazard in fishery products, and there is increasing demand for new analytical techniques to control it more effectively. Here, the fluorescent properties of cod bones under UV illumination were investigated, and the maximal wavelengths for excitation and emission were determined to be 320 nm and 515 nm, respectively, demonstrating significantly different fluorescence characteristics and much higher fluorescence intensity compared to those of fillet muscles. Based on the results, UV fluorescence-assisted candling for the detection of bones in fishery products was developed for the first time. Using cod fillets as samples, the detection ratio of this technique was calculated as 90.86%, significantly higher than that of traditional candling under daylight (76.78%). Moreover, the working efficiency of the new technique was about 26% higher than that of the traditional method. A UV fluorescence imaging framework was also developed, and a method for automatic identification of the fish bones in the cod fillets based on the linear discriminant analysis proposed by Fisher was preliminarily realized, but the detection ratio was demonstrated to be relatively poor compared to those of candling techniques. These results allow us to suggest UV-based methods as new and promising approaches for routine monitoring of bones in fishery products.

  9. Removal of COD from laundry wastewater by electrocoagulation/electroflotation

    Energy Technology Data Exchange (ETDEWEB)

    Wang, C.-T. [Department of Safety Health and Environmental Engineering, Chung Hwa University of Medical Technology, Tainan County, Hsien 717, Taiwan (China)], E-mail: ctwwang@mail.hwai.edu.tw; Chou, W.-L. [Department of Safety Health and Environmental Engineering and Institute of Occupational Safety and Hazard Prevention, HungKuang University, Sha-Lu, Taichung 433, Taiwan (China); Kuo, Y.-M. [Department of Safety Health and Environmental Engineering, Chung Hwa University of Medical Technology, Tainan County, Hsien 717, Taiwan (China)

    2009-05-15

    The removal efficiency of COD in the treatment of simulated laundry wastewater using electrocoagulation/electroflotation technology is described. The experimental results showed that the removal efficiency was better, reaching to about 62%, when applying ultrasound to the electrocoagulation cell. The solution pH approached neutrality in all experimental runs. The optimal removal efficiency of COD was obtained by using the applied voltage of 5 V when considering the energy efficiency and the acceptable removal efficiency simultaneously. The Cl{sup -} concentration of less than 2500 ppm had a positive effect on the removal efficiency. The performance of the monopolar connection of electrodes was better than that of the bipolar connection in this work. In addition, the removal efficiency of using Al electrodes was higher in comparison with using Fe electrodes in the study. The highest COD removal amount per joule was found to be 999 mg dm{sup -3} kW h{sup -1} while using two Al electrodes, although the removal efficiency increased with the number of Al plates.

  10. Effect of produced water on cod (Gadus morhua) immune responses

    Energy Technology Data Exchange (ETDEWEB)

    Hamoutene, D.; Mabrouk, G.; Samuelson, S.; Mansour, A.; Lee, K. [Fisheries and Oceans Canada, Dartmouth, NS (Canada). Maritimes Region, Ocean Sciences Division; Volkoff, H.; Parrish, C. [Memorial Univ. of Newfoundland, St. John' s, NL (Canada); Mathieu, A. [Oceans Ltd., St. John' s, NL (Canada)

    2007-07-01

    Studies have shown that produced water (PW) discharged from North Sea offshore platforms affects the biota at greater distances from operational platforms than originally presumed. According to PW dispersion simulations, dilution by at least 240 times occurs within 50-100 m, and up to 9000 times by 20 km from the discharge. In this study, the effect of PW on cod immunity was investigated by exposing fish to 0, 100 ppm (x 10,000 dilution) or 200 ppm (x 500) of PW for 76 days. Immune responses were evaluated at the end of the exposure. Fish from the 3 groups were injected with Aeromonas salmonicida lipopolysaccharides (LPS). Blood cell observation and flow cytometry were used to investigate the serum cortisol levels and gill histology along with ratios and respiratory burst (RB) responses of both circulating and head-kidney white blood cells (WBCs). The study revealed that baseline immunity and stress response were not affected by PW, other than an irritant-induced change in gill cells found in treated cod. In all groups, LPS injection resulted in a pronounced decrease in RB of head-kidney cells and an increase in serum cortisol and protein levels. However, the group exposed to 200 ppm of PW exhibited the most significant changes. LPS injection was also shown to influence WBC ratios, but further studies are needed to determine if this impact is stronger in fish exposed to PW. This study suggested an effect of PW on cod immunity after immune challenge with LPS.

  11. Removal of COD from laundry wastewater by electrocoagulation/electroflotation

    International Nuclear Information System (INIS)

    Wang, C.-T.; Chou, W.-L.; Kuo, Y.-M.

    2009-01-01

    The removal efficiency of COD in the treatment of simulated laundry wastewater using electrocoagulation/electroflotation technology is described. The experimental results showed that the removal efficiency was better, reaching to about 62%, when applying ultrasound to the electrocoagulation cell. The solution pH approached neutrality in all experimental runs. The optimal removal efficiency of COD was obtained by using the applied voltage of 5 V when considering the energy efficiency and the acceptable removal efficiency simultaneously. The Cl - concentration of less than 2500 ppm had a positive effect on the removal efficiency. The performance of the monopolar connection of electrodes was better than that of the bipolar connection in this work. In addition, the removal efficiency of using Al electrodes was higher in comparison with using Fe electrodes in the study. The highest COD removal amount per joule was found to be 999 mg dm -3 kW h -1 while using two Al electrodes, although the removal efficiency increased with the number of Al plates

  12. Differential response of continental stock complexes of Atlantic salmon (Salmo salar) to the Atlantic Multidecadal Oscillation

    Science.gov (United States)

    Friedland, Kevin D.; Shank, Burton V.; Todd, Christopher D.; McGinnity, Philip; Nye, Janet A.

    2014-05-01

    Atlantic salmon, Salmo salar, in the North Atlantic are managed as a set of population complexes distributed in North America and Europe. In recent years, these complexes have experienced reduced marine survival and many populations within the complexes are at risk, especially those at the southern ends of the species amphi-Atlantic range. Atlantic salmon is an anadromous fish dividing its life history between residence in freshwater and the marine environment. The freshwater portion of the life history includes spawning and the rearing of juveniles where in-river production has tended to be relatively stable, whereas the first year at sea, termed the post-smolt year, is characterized by more variable rates of mortality. Although their habitats are widely separated geographically along the North Atlantic seaboards, strong recruitment coherence exists between North American and European stock complexes. This recruitment coherence is correlated with ocean temperature variation associated with the Atlantic Multidecadal Oscillation (AMO). The North Atlantic Oscillation (NAO) appears to be relatively unimportant as a driver of salmon abundance. The mechanism determining the link between AMO-related thermal variation and abundance appears to differ fundamentally for the two continental stock groupings. Whereas ocean climate variability during the first springtime months of juvenile salmon migration to sea appears to be important to the survival of North American stocks, summer climate variation appears to be central to adult recruitment variation for European stocks. This contrast in seasonal effects appears to be related to the varying roles of predation pressure and size-related mortality on the continental stock complexes. The anticipated warming due to global climate change will impose thermal conditions on salmon populations outside historical context and challenge the ability of many populations to persist.

  13. Disentangling the effects of evolutionary, demographic, and environmental factors influencing genetic structure of natural populations: Atlantic herring as a case study

    DEFF Research Database (Denmark)

    Gaggiotti, Oscar E.; Bekkevold, Dorte; Jørgensen, Hanne B.H.

    2009-01-01

    , on the other hand, seems to have been largely eroded, which is not surprising given the large reproductive potential and presumed enormous local effective population sizes of pelagic fish that constrain the effect of stochastic processes. The approach we used can in principle be applied to any abundant...... carried out separate analyses of neutral and selected genetic variation, which allowed us to establish that the two most important factors affecting population structure were selection due to salinity at spawning sites and feeding migrations. The genetic signal left by the demographic history of herring...

  14. Multi-decadal scale variability in the eastern Baltic cod fishery 1550-1860 - Evidence and causes

    DEFF Research Database (Denmark)

    MacKenzie, Brian; Bager, M.; Ojaveer, H.

    2007-01-01

    in the Baltic as developed and implemented by organisations such as the International Council for the Exploration of the Sea (ICES), the Baltic Marine Environment Protection Commission (HELCOM), the nine coastal countries and the European Union includes recovery of the cod population, a reduction in nutrient...... is unknown, as is the relative role of fishing, climate variability/regimes, eutrophication and reduction of marine mammal predator populations. We have begun to investigate whether historical fisheries information (landings, effort, distribution) from before the 1880s is available in Baltic archives...

  15. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877) - Rodentia, Echimyidae - population with varying jackfruit tree (Artocarpus heterophyllus L.) abundances.

    Science.gov (United States)

    Mello, J H F; Moulton, T P; Raíces, D S L; Bergallo, H G

    2015-01-01

    We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and density of A. heterophyllus. One observed effect was the increased population size of the spiny-rat Trinomys dimidiatus within the grids where the jackfruit trees were present. Therefore we decided to create a mathematical model for this species, based on the Verhulst-Pearl logistic equation. Our objectives were i) to calculate the carrying capacity K based on real data of the involved species and the environment; ii) propose and evaluate a mathematical model to estimate the population size of T. dimidiatus based on the monthly seed production of jackfruit tree, Artocarpus heterophyllus and iii) determinate the minimum jackfruit tree seed production to maintain at least two T. dimidiatus individuals in one study grid. Our results indicated that the predicted values by the model for the carrying capacity K were significantly correlated with real data. The best fit was found considering 20~35% energy transfer efficiency between trophic levels. Within the scope of assumed premises, our model showed itself to be an adequate simulator for Trinomys dimidiatus populations where the invasive jackfruit tree is present.

  16. About rats and jackfruit trees: modeling the carrying capacity of a Brazilian Atlantic Forest spiny-rat Trinomys dimidiatus (Günther, 1877 – Rodentia, Echimyidae – population with varying jackfruit tree (Artocarpus heterophyllus L. abundances

    Directory of Open Access Journals (Sweden)

    JHF Mello

    Full Text Available We carried out a six-year study aimed at evaluating if and how a Brazilian Atlantic Forest small mammal community responded to the presence of the invasive exotic species Artocarpus heterophyllus, the jackfruit tree. In the surroundings of Vila Dois Rios, Ilha Grande, RJ, 18 grids were established, 10 where the jackfruit tree was present and eight were it was absent. Previous results indicated that the composition and abundance of this small mammal community were altered by the presence and density of A. heterophyllus. One observed effect was the increased population size of the spiny-rat Trinomys dimidiatus within the grids where the jackfruit trees were present. Therefore we decided to create a mathematical model for this species, based on the Verhulst-Pearl logistic equation. Our objectives were i to calculate the carrying capacity K based on real data of the involved species and the environment; ii propose and evaluate a mathematical model to estimate the population size of T. dimidiatus based on the monthly seed production of jackfruit tree, Artocarpus heterophyllus and iii determinate the minimum jackfruit tree seed production to maintain at least two T. dimidiatus individuals in one study grid. Our results indicated that the predicted values by the model for the carrying capacity K were significantly correlated with real data. The best fit was found considering 20~35% energy transfer efficiency between trophic levels. Within the scope of assumed premises, our model showed itself to be an adequate simulator for Trinomys dimidiatus populations where the invasive jackfruit tree is present.

  17. Population dynamics of Siderastrea stellata Verrill, 1868 from Rocas Atoll, RN: implications for predicted climate change impacts at the only South Atlantic atoll

    Directory of Open Access Journals (Sweden)

    BARBARA R. PINHEIRO

    Full Text Available ABSTRACT Coral reefs are one of the most vulnerable ecosystems to ocean warming and acidification, and it is important to determine the role of reef building species in this environment in order to obtain insight into their susceptibility to expected impacts of global changes. Aspects of the life history of a coral population, such as reproduction, growth and size-frequency can contribute to the production of models that are used to estimate impacts and potential recovery of the population, acting as a powerful tool for the conservation and management of those ecosystems. Here, we present the first evidence of Siderastrea stellata planulation, its early growth, population size-frequency distribution and growth rate of adult colonies in Rocas Atoll. Our results, together with the environmental protection policies and the absence of anthropogenic pressures, suggest that S. stellata population may have a good potential in the maintenance and recovery in the atoll. However, our results also indicate an impact on corals' recruitment, probably as a consequence of the positive temperature anomaly that occurred in 2010. Thus, despite the pristine status of Rocas Atoll, the preservation of its coral community seems to be threatened by current global changes, such as more frequent thermal stress events.

  18. Population dynamics of Siderastrea stellata Verrill, 1868 from Rocas Atoll, RN: implications for predicted climate change impacts at the only South Atlantic atoll.

    Science.gov (United States)

    Miranda, Andrea L; Cordeiro, Soraia M; Reis, Joice N; Cardoso, Lucas G; Guimarães, Alaíse G

    2017-01-01

    Coral reefs are one of the most vulnerable ecosystems to ocean warming and acidification, and it is important to determine the role of reef building species in this environment in order to obtain insight into their susceptibility to expected impacts of global changes. Aspects of the life history of a coral population, such as reproduction, growth and size-frequency can contribute to the production of models that are used to estimate impacts and potential recovery of the population, acting as a powerful tool for the conservation and management of those ecosystems. Here, we present the first evidence of Siderastrea stellata planulation, its early growth, population size-frequency distribution and growth rate of adult colonies in Rocas Atoll. Our results, together with the environmental protection policies and the absence of anthropogenic pressures, suggest that S. stellata population may have a good potential in the maintenance and recovery in the atoll. However, our results also indicate an impact on corals' recruitment, probably as a consequence of the positive temperature anomaly that occurred in 2010. Thus, despite the pristine status of Rocas Atoll, the preservation of its coral community seems to be threatened by current global changes, such as more frequent thermal stress events.

  19. Pacific halibut bycatch in Pacific cod fisheries in the Bering Sea: an analysis to evaluate area-time management

    Science.gov (United States)

    Adlerstein, Sara A.; Trumble, Robert J.

    1998-03-01

    Mortality of discarded Pacific halibut bycatch from Pacific cod fisheries in the Bering Sea leads to significant losses in the halibut setline and in the Pacific cod fisheries. The commercial halibut fishery loses yield because of catch limit reductions to compensate the resource for lost spawning potential and because halibut killed as bycatch will not be available for subsequent harvest, and the cod fisheries may lose harvest if they reach a bycatch mortality limit before reaching allowed catch. In this study, significant differences in Pacific halibut bycatch rates and associated yield losses were found among months and areas of the Bering Sea in the longline and trawl fisheries for Pacific cod in 1990-1992. Bycatch rates were usually highest in late spring and early summer and in areas close to the Unimak Pass. With the exception of 1992, yield loss in the longline fishery was around 1 kg per kg of bycatch mortality, irrespective of where or when bycatch occurred. In the trawl fishery, loss of halibut yield varied from 1 to 4 kg per kg of bycatch mortality. Highest halibut net yield losses per tonne of groundfish harvest usually coincided with highest bycatch rates. When both fisheries operated in one area, trawl bycatch often imposed higher yield losses than longline bycatch, despite lower bycatch rates. Bycatch was affected by the strong 1987 halibut year class. Highest bycatch and yield loss rates occurred in the trawl fishery in 1990 and 1991 when the population was dominated by halibut age-3 and -4, and in the longline fishery in 1992 as fish reached age-5.

  20. Seasonal prevalence and intensity of follicular atresia in Baltic cod Gadus morhua callarias L

    DEFF Research Database (Denmark)

    Kraus, Gerd; Tomkiewicz, Jonna; Diekmann, R.

    2008-01-01

    of the physical disector method and volume fraction (Delesse principle). Atretic oocytes were observed in 32% of the ovaries. Prevalence of atresia was independent of female size, but increased significantly with declining female condition from prespawning and through the spawning stages. The relative intensity...... of atresia, i.e. number of atretic oocytes in relation to normally developed vitellogenic oocytes, was low amounting to 1.4% on average. Similar to prevalence, relative intensity of atresia differed significantly between maturity stages and increased with decreasing female condition. The population egg loss......In the present study, 307 ovaries of eastern Baltic cod Gadus morhua callarias sampled during the prespawning and spawning season 2000 were analysed histologically to estimate the seasonal prevalence and intensity of atresia. The number of atretic oocytes per ovary was estimated using a combination...

  1. Characterizing surf zone injuries from the five most populated beaches on the Atlantic-fronting Delaware coast: Delaware surf zone injury demographics.

    Science.gov (United States)

    Doelp, Matthew B; Puleo, Jack A; Cowan, Paul; Arford-Granholm, Michelle

    2017-12-24

    Beaches are a popular destination for recreation activities. Surf zone injuries (SZI) can occur resulting from a variety of in-water activities. Little is known regarding the sustained injury types, or demographics of injured persons and activities leading to injuries. This study examines the distribution of SZI types, activities and populations occurring on Delaware Beaches as recorded by a local level III trauma center (Department of Emergency Medicine at Beebe Healthcare in Lewes, Delaware). There were 2021 injuries over the eight study years (2010-2017). The relative demographics of the injured population are similar despite fluctuating injury totals (mean [SD], 253.1 [104.4]). Non-locals (n=1757) were 6.7 times more likely to be injured as their local (n=264) counterparts (RR, 2.62; 95% CI, 2.08-3.31). Males (n=1258) were 1.7 times more likely to be injured than their female (n=763) counterparts (RR, 1.29; 95% CI, 1.21-1.37). Serious injuries, defined as patients requiring admission to a trauma service, represented 9.1% (n=184) of injuries. Fatal SZI (n=6) were categorized as serious injuries. Wading (50.1%) was found to be the dominant activity associated with injury followed by body surfing (18.4%), and body boarding (13.3%). To the authors' knowledge, this study is one of the first to investigate long-term trends in SZI data, injury activity, and demographics. Better understanding of the characteristics of injuries will allow for improved awareness techniques, targeted at populations with higher injury rates. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. The early colonial atlantic world: New insights on the African Diaspora from isotopic and ancient DNA analyses of a multiethnic 15th-17th century burial population from the Canary Islands, Spain.

    Science.gov (United States)

    Santana, Jonathan; Fregel, Rosa; Lightfoot, Emma; Morales, Jacob; Alamón, Martha; Guillén, José; Moreno, Marco; Rodríguez, Amelia

    2016-02-01

    The Canary Islands are considered one of the first places where Atlantic slave plantations with labourers of African origin were established, during the 15th century AD. In Gran Canaria (Canary Islands, Spain), a unique cemetery dated to the 15th and 17th centuries was discovered adjacent to an ancient sugar plantation with funerary practices that could be related to enslaved people. In this article, we investigate the origin and possible birthplace of each individual buried in this cemetery, as well as the identity and social status of these people. The sample consists of 14 individuals radiocarbon dated to the 15th and 17th centuries AD. We have employed several methods, including the analysis of ancient human DNA, stable isotopes, and skeletal markers of physical activity. 1) the funerary practices indicate a set of rituals not previously recorded in the Canary Islands; 2) genetic data show that some people buried in the cemetery could have North-African and sub-Saharan African lineages; 3) isotopic results suggest that some individuals were born outside Gran Canaria; and 4) markers of physical activity show a pattern of labour involving high levels of effort. This set of evidence, along with information from historical sources, suggests that Finca Clavijo was a cemetery for a multiethnic marginalized population that had being likely enslaved. Results also indicate that this population kept practicing non-Christian rituals well into the 17th century. We propose that this was possible because the location of the Canaries, far from mainland Spain and the control of the Spanish Crown, allowed the emergence of a new society with multicultural origins that was more tolerant to foreign rituals and syncretism. © 2015 Wiley Periodicals, Inc.

  3. Atlantic Salmon Telemetry Monitoring

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Annual telemetry data are collected as part of specific projects (assessments within watersheds) or as opportunistic efforts to characterize Atlantic salmon smolt...

  4. GARP Atlantic Tropical Experiment

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The GARP Atlantic Tropical Experiment (GATE) was the first major international experiment of the Global Atmospheric Research Program (GARP). It was conducted over...

  5. New type of canned cod gonads and liver pastes

    Directory of Open Access Journals (Sweden)

    Grokhovsky V. A.

    2016-09-01

    Full Text Available The urgency of rational way of processing the offal of the Gadidae family (liver and gonads for food purposes has been proved. The possibility of using the frozen gonads (milt and caviar and the liver of the cod in the human nutrition (especially for the people of elderly age has been researched. The frozen gonads with addition of fish liver are proven to be used for producing the canned foods with high quality level. The physical, chemical and microbiological characteristics of the product have been determined by the standardized methods. The quality level of canned foods has been obtained using the developed criteria of the objective evaluation of the quality. The specimens of the canned pastes produced from the frozen cod milt, caviar and liver using different compositions have been researched. Near-to-optimal composition of the new product has been defined. The quality level of canned food is 88.6 %. The commercial sterility of the canned food specimens prepared using the developed technology has been established. The chemical composition and the sensory characteristics of canned food have been researched. It has been established that protein content in the canned food is 12.9 %, fat content – 13.5 %, water content – 71.2 %, sodium chloride content – 1.3 %, carbohydrates content – 0.5 %. The product is the uniform, finely ground, evenly mixed mass with the presence of the separate caviar grains. The color of the paste is light-beige. The canned food has the tender consistency, pleasant taste and aroma. The energy value of the product is 678 kJ (162 kcal. Using the frozen cod caviar, milt and liver for producing the developed assortment of canned foods will make it possible to solve the problem of the complex processing of fish, and also to manufacture the canned food of high quality on the shore enterprises from the frozen fish offal (caviar, milt and liver all the year round.

  6. Genetic ancestry effects on the distribution of toll-like receptors (TLRs) gene polymorphisms in a population of the Atlantic Forest, São Paulo, Brazil.

    Science.gov (United States)

    Guimarães, Lilian O; Bajay, Miklos Maximiliano; Monteiro, Eliana F; Wunderlich, Gerhard; Santos, Sidney E; Kirchgatter, Karin

    2018-02-01

    The innate immune system governed by toll-like receptors (TLRs) provides the first line of defense against pathogens. Surface-localized TLR1 and TLR6 are known to detect parasite components. TLR encoding genes were shown to display signatures of recent positive selection in Europeans and might be involved in local adaptation at immune-related genes. To verify the influence of Brazilian population admixture on the distribution of polymorphisms in TLRs, we analyzed the genotype frequencies of 24 polymorphisms distributed across five TLR genes in a Southeastern Brazilian population where autochthonous cases of malaria occur in small foci of transmission. The estimation of ancestry showed mainly European ancestry (63%) followed by African ancestry (22%). Mean proportions of European ancestry differed significantly between the genotypes of the TLR1 (I602S) gene and in the TLR6 (P249S) gene. The chance of having the G allele in TLR1 gene increases as European ancestry increases as well as the chance of having the T allele in the TLR6 gene. The 602S allele is related to a ''hypo-responsiveness'' possibly explaining the high prevalence of asymptomatic malaria cases in areas of Southeastern Brazil. Our results underline the necessity to include informative ancestry markers in genetic association studies in order to avoid biased results. Copyright © 2017 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.

  7. Strong genetic differentiation among east Atlantic populations of the sword razor shell ( Ensis siliqua) assessed with mtDNA and RAPD markers

    Science.gov (United States)

    Arias, Alberto; Fernández-Moreno, Mercedes; Fernández-Tajes, Juan; Gaspar, Miguel B.; Méndez, Josefina

    2011-03-01

    The sword razor shell Ensis siliqua (Linnaeus, 1758) is a bivalve with a high commercial value being appreciated in fresh and processed markets. However, the genetic studies carried out in populations of E. siliqua are scarce. In this work, the genetic variability and differentiation of the sword razor shell was assessed using PCR-RFLPs of a fragment of the 16S rRNA mitochondrial gene and random amplified polymorphic loci (RAPD) in nine localities from Ireland, Spain, and Portugal. In the 314 individuals examined for the mitochondrial fragment, 12 composite haplotypes were observed; meanwhile, a unique phenotype was observed for each of the 242 individuals analyzed with 61 RAPD loci. Two of the mitochondrial composite haplotypes accounted for the majority of individuals (89.81%) and showed a remarkably disjoint distribution between Irish and Iberian samples, with the exception of Aveiro which exhibited as the most frequent haplotype the same found in Ireland. The level of variability observed for each sample was generally correlated with both types of markers and the results obtained suggest the existence of a strong population differentiation between Irish and Iberian localities, except for the Portuguese sample from Aveiro which is surprisingly closer to Irish individuals, although it is probably highly differentiated.

  8. Suitability of otolith microchemistry for stock separation of Baltic cod

    DEFF Research Database (Denmark)

    Heidemann, F; Marohn, L; Hinrichsen, HH

    2012-01-01

    differences between individuals from the eastern and the western Baltic Sea and between North Sea and Baltic Sea samples. Sr/Ca, Ba/Ca, Y/Ca, Mg/Ca, Zr/Ca and Mn/Ca ratios had the strongest discriminatory power. A further separation of individuals caught in 3 different spawning grounds of the eastern Baltic......, however, was not possible. Elemental compositions from the core regions of otoliths from young of the year cod caught in eastern and western Baltic Sea spawning grounds showed significant differences in Sr/Ca, Ba/Ca and Mg/Ca concentrations. Analyses of similarities again showed significant differences...

  9. Lessons for fisheries management from the EU cod recovery plan

    DEFF Research Database (Denmark)

    Kraak, S.B.M.; Bailey, N.; Cardinale, M.

    2013-01-01

    Member States to 'buy back' or increase fishing effort for fleet segments engaged in cod-avoidance measures. The stipulated fishing mortality reductions have not been achieved. On the positive side, the 'buy-back' instrument has led to increased uptake of selective gear and implementation of permanent...... in targeted fisheries, although fishers experienced them as prohibiting the full uptake of other quotas. Recommendations for future plans include (i) management through catch rather than landings quotas, (ii) the internalisation of the costs of exceeding quotas, (iii) use of more selective gear types, (iv...

  10. Nutritional condition and vertical distribution of Baltic cod larvae

    DEFF Research Database (Denmark)

    Grønkjær, P.; Clemmesen, C.; St. John, Michael

    1997-01-01

    Newly hatched Baltic cod Gadus morhua larvae are typically found at depths >60 m. This is a region of low light and prey availability, hence generating the hypothesis that larvae have to migrate from hatching depth to the surface layer to avoid starvation and improve their nutritional condition...... aged 2-25 days (median 10 days) ranged from 0.4 to 6.2, corresponding to levels exhibited by starving and fast growing larvae in laboratory calibration studies (starvation, protein growth rate, G(pi)=-12.2% day(-1); fast-growing larvae, G(pi)=14.1% day(-1)) respectively. Seventy per cent of the field...

  11. Improved management based on stock identification of eastern and western Baltic cod

    DEFF Research Database (Denmark)

    Hüssy, Karin; Bastardie, Francois; Eero, Margit

    The objective of this project was to establish an empirically founded knowledge base for the sustainable exploitation of the western Baltic cod stock by including the complex stock structure and migration patterns. Stock mapping: Extensive immigration of “Eastern” cod into the Arkona Basin (SD 24......) within the “Western” cod’s management unit was documented using high-powered genetic tools. The majority (91%) of all spawning fish caught in SD 24 in 2011 were “Eastern” cod and only 9% were from the “Western” stock. The results suggest that the stock structure in the Arkona Basin is highly influenced...... by mixing of genetically separate stocks. Trends in mixing: Since the 1980’s where cod in SD 24 consisted primarily of “Western” type, the proportion of “Eastern” cod has increased, particularly since 2005. Throughout that period, the immigration of “Eastern” cod into SD 24 consisted primarily of adult...

  12. Profile data collected to support the assessment of the physiological status of phytoplankton state: population and individual cell measurement cruise in the NW Atlantic, October 1 - 15, 2001 (NODC Accession 0002256)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and phytoplankton data were collected using XBT and CTD casts in the Northwest Atlantic Ocean from R/V ENDEAVOR from 01 October 2001 to 15...

  13. Recovery in eastern Baltic cod: is increased recruitment caused by decreased predation on early life stages?

    DEFF Research Database (Denmark)

    Neumann, Viola; Köster, Fritz; Schaber, M.

    2014-01-01

    Cod (Gadus morhua) recruitment in the eastern Baltic Sea is influenced by predation on early life stages by sprat (Sprattus sprattus) and herring (Clupea harengus), which is considered as one of the mechanisms preventing cod recovery in the 1990s. In the light of improved cod recruitment...... in the second half of the 2000s, new analyses of stomach content of sprat and herring were conducted, to elucidate the contribution of changes in predation pressure on cod recruitment. Comparison of stomach contents of sprat and herring in 2004–2008 with data from the 1990s showed a similar diet composition...

  14. Colony size-frequency distributions among different populations of the scleractinan coral Siderastrea stellata in Southwestern Atlantic: implications for life history patterns

    Directory of Open Access Journals (Sweden)

    Monica Moraes Lins de Barros

    2006-12-01

    Full Text Available Colony size-frequency distributions of reef corals may be used to infer growth potential and population responses upon environmental changes. The present paper compares the size structure of colonies of Siderastrea stellata Verrill, 1868,among 11 sites, six of them distributed along a gradient of sediment deposition in Abrolhos, Bahia, Brazil (18º S. Results indicated that the population structure is likely to be influenced by local conditions, rather than large scale factors, such as latitude. The 11 distributions, however, showed higher frequencies of small size classes. Class 1 (up to 2.5 cm diameter was always present and the frequency of colonies from size class 3 (10 cm diameter tended to decrease in all sites. Comparison among the six Abrolhos sites showed that S. stellata has advantages at sites with intermediate sedimentation, where colonies attain larger sizes, probably, reflecting a higher survivorship over time. The present study showed that, despite the influence of environmental conditions on parameters of the populations such as size of colony, the life history strategy of S. stellata reflects a local adaptation that allows its development and survivorship in shallow waters and horizontal substrates, sites characterized by high mortality rates.Distribuições de freqüências de classes de tamanho de colônias de corais recifais, associadas a dados de fecundidade e crescimento, podem ser utilizadas para inferir o potencial de crescimento e respostas da população frente às variações ambientais. Apresentamos análise da estrutura de tamanho de colônias do coral Siderastrea stellata Verrill, 1868, em 11 locais, seis desses distribuídos ao longo de um gradiente de sedimentação em Abrolhos, Bahia, Brasil (18ºS. Os resultados demonstraram ausência de um padrão latitudinal, indicando maior influência de fatores locais. Em Abrolhos, locais com taxas de deposição de sedimento intermediárias apresentaram os maiores

  15. It is the economy, stupid! Projecting the fate of fish populations using ecological-economic modeling.

    Science.gov (United States)

    Quaas, Martin F; Reusch, Thorsten B H; Schmidt, Jörn O; Tahvonen, Olli; Voss, Rudi

    2016-01-01

    Four marine fish species are among the most important on the world market: cod, salmon, tuna, and sea bass. While the supply of North American and European markets for two of these species - Atlantic salmon and European sea bass - mainly comes from fish farming, Atlantic cod and tunas are mainly caught from wild stocks. We address the question what will be the status of these wild stocks in the midterm future, in the year 2048, to be specific. Whereas the effects of climate change and ecological driving forces on fish stocks have already gained much attention, our prime interest is in studying the effects of changing economic drivers, as well as the impact of variable management effectiveness. Using a process-based ecological-economic multispecies optimization model, we assess the future stock status under different scenarios of change. We simulate (i) technological progress in fishing, (ii) increasing demand for fish, and (iii) increasing supply of farmed fish, as well as the interplay of these driving forces under different scenarios of (limited) fishery management effectiveness. We find that economic change has a substantial effect on fish populations. Increasing aquaculture production can dampen the fishing pressure on wild stocks, but this effect is likely to be overwhelmed by increasing demand and technological progress, both increasing fishing pressure. The only solution to avoid collapse of the majority of stocks is institutional change to improve management effectiveness significantly above the current state. We conclude that full recognition of economic drivers of change will be needed to successfully develop an integrated ecosystem management and to sustain the wild fish stocks until 2048 and beyond. © 2015 John Wiley & Sons Ltd.

  16. Evaluation of simultaneous nutrient and COD removal with polyhydroxybutyrate (PHB) accumulation using mixed microbial consortia under anoxic condition and their bioinformatics analysis.

    Science.gov (United States)

    Jena, Jyotsnarani; Kumar, Ravindra; Dixit, Anshuman; Pandey, Sony; Das, Trupti

    2015-01-01

    Simultaneous nitrate-N, phosphate and COD removal was evaluated from synthetic waste water using mixed microbial consortia in an anoxic environment under various initial carbon load (ICL) in a batch scale reactor system. Within 6 hours of incubation, enriched DNPAOs (Denitrifying Polyphosphate Accumulating Microorganisms) were able to remove maximum COD (87%) at 2 g/L of ICL whereas maximum nitrate-N (97%) and phosphate (87%) removal along with PHB accumulation (49 mg/L) was achieved at 8 g/L of ICL. Exhaustion of nitrate-N, beyond 6 hours of incubation, had a detrimental effect on COD and phosphate removal rate. Fresh supply of nitrate-N to the reaction medium, beyond 6 hours, helped revive the removal rates of both COD and phosphate. Therefore, it was apparent that in spite of a high carbon load, maximum COD and nutrient removal can be maintained, with adequate nitrate-N availability. Denitrifying condition in the medium was evident from an increasing pH trend. PHB accumulation by the mixed culture was directly proportional to ICL; however the time taken for accumulation at higher ICL was more. Unlike conventional EBPR, PHB depletion did not support phosphate accumulation in this case. The unique aspect of all the batch studies were PHB accumulation was observed along with phosphate uptake and nitrate reduction under anoxic conditions. Bioinformatics analysis followed by pyrosequencing of the mixed culture DNA from the seed sludge revealed the dominance of denitrifying population, such as Corynebacterium, Rhodocyclus and Paraccocus (Alphaproteobacteria and Betaproteobacteria). Rarefaction curve indicated complete bacterial population and corresponding number of OTUs through sequence analysis. Chao1 and Shannon index (H') was used to study the diversity of sampling. "UCI95" and "LCI95" indicated 95% confidence level of upper and lower values of Chao1 for each distance. Values of Chao1 index supported the results of rarefaction curve.

  17. Evaluation of simultaneous nutrient and COD removal with polyhydroxybutyrate (PHB accumulation using mixed microbial consortia under anoxic condition and their bioinformatics analysis.

    Directory of Open Access Journals (Sweden)

    Jyotsnarani Jena

    Full Text Available Simultaneous nitrate-N, phosphate and COD removal was evaluated from synthetic waste water using mixed microbial consortia in an anoxic environment under various initial carbon load (ICL in a batch scale reactor system. Within 6 hours of incubation, enriched DNPAOs (Denitrifying Polyphosphate Accumulating Microorganisms were able to remove maximum COD (87% at 2 g/L of ICL whereas maximum nitrate-N (97% and phosphate (87% removal along with PHB accumulation (49 mg/L was achieved at 8 g/L of ICL. Exhaustion of nitrate-N, beyond 6 hours of incubation, had a detrimental effect on COD and phosphate removal rate. Fresh supply of nitrate-N to the reaction medium, beyond 6 hours, helped revive the removal rates of both COD and phosphate. Therefore, it was apparent that in spite of a high carbon load, maximum COD and nutrient removal can be maintained, with adequate nitrate-N availability. Denitrifying condition in the medium was evident from an increasing pH trend. PHB accumulation by the mixed culture was directly proportional to ICL; however the time taken for accumulation at higher ICL was more. Unlike conventional EBPR, PHB depletion did not support phosphate accumulation in this case. The unique aspect of all the batch studies were PHB accumulation was observed along with phosphate uptake and nitrate reduction under anoxic conditions. Bioinformatics analysis followed by pyrosequencing of the mixed culture DNA from the seed sludge revealed the dominance of denitrifying population, such as Corynebacterium, Rhodocyclus and Paraccocus (Alphaproteobacteria and Betaproteobacteria. Rarefaction curve indicated complete bacterial population and corresponding number of OTUs through sequence analysis. Chao1 and Shannon index (H' was used to study the diversity of sampling. "UCI95" and "LCI95" indicated 95% confidence level of upper and lower values of Chao1 for each distance. Values of Chao1 index supported the results of rarefaction curve.

  18. Genetic diversity of Bromeliaceae species from the Atlantic Forest.

    Science.gov (United States)

    Sheu, Y; Cunha-Machado, A S; Gontijo, A B P L; Favoreto, F C; Soares, T B C; Miranda, F D

    2017-04-20

    The Bromeliaceae family includes a range of species used for many purposes, including ornamental use and use as food, medicine, feed, and fiber. The state of Espírito Santo, Brazil is a center of diversity for this family in the Atlantic Forest. We evaluated the genetic diversity of five populations of the Bromeliaceae family, including specimens of the genera Aechmea, Billbergia (subfamily Bromelioideae), and Pitcairnia (subfamily Pitcairnioidea), all found in the Atlantic Forest and distributed in the state of Espírito Santo. The number of alleles per locus in populations ranged from two to six and the fixation index (F), estimated for some simple sequence repeats in bromeliad populations, was less than zero in all populations. All markers in the Pitcairnia flammea population were in Hardy-Weinberg equilibrium (P Atlantic Forest remnants in the south of Espírito Santo state.

  19. Real-time ichthyoplankton drift in Northeast Arctic cod and Norwegian spring-spawning herring.

    Science.gov (United States)

    Vikebø, Frode B; Ådlandsvik, Bjørn; Albretsen, Jon; Sundby, Svein; Stenevik, Erling Kåre; Huse, Geir; Svendsen, Einar; Kristiansen, Trond; Eriksen, Elena

    2011-01-01

    Individual-based biophysical larval models, initialized and parameterized by observations, enable numerical investigations of various factors regulating survival of young fish until they recruit into the adult population. Exponentially decreasing numbers in Northeast Arctic cod and Norwegian Spring Spawning herring early changes emphasizes the importance of early life history, when ichthyoplankton exhibit pelagic free drift. However, while most studies are concerned with past recruitment variability it is also important to establish real-time predictions of ichthyoplankton distributions due to the increasing human activity in fish habitats and the need for distribution predictions that could potentially improve field coverage of ichthyoplankton. A system has been developed for operational simulation of ichthyoplankton distributions. We have coupled a two-day ocean forecasts from the Norwegian Meteorological Institute with an individual-based ichthyoplankton model for Northeast Arctic cod and Norwegian Spring Spawning herring producing daily updated maps of ichthyoplankton distributions. Recent years observed spawning distribution and intensity have been used as input to the model system. The system has been running in an operational mode since 2008. Surveys are expensive and distributions of early stages are therefore only covered once or twice a year. Comparison between model and observations are therefore limited in time. However, the observed and simulated distributions of juvenile fish tend to agree well during early fall. Area-overlap between modeled and observed juveniles September 1(st) range from 61 to 73%, and 61 to 71% when weighted by concentrations. The model system may be used to evaluate the design of ongoing surveys, to quantify the overlap with harmful substances in the ocean after accidental spills, as well as management planning of particular risky operations at sea. The modeled distributions are already utilized during research surveys to

  20. Real-time ichthyoplankton drift in Northeast Arctic cod and Norwegian spring-spawning herring.

    Directory of Open Access Journals (Sweden)

    Frode B Vikebø

    Full Text Available BACKGROUND: Individual-based biophysical larval models, initialized and parameterized by observations, enable numerical investigations of various factors regulating survival of young fish until they recruit into the adult population. Exponentially decreasing numbers in Northeast Arctic cod and Norwegian Spring Spawning herring early changes emphasizes the importance of early life history, when ichthyoplankton exhibit pelagic free drift. However, while most studies are concerned with past recruitment variability it is also important to establish real-time predictions of ichthyoplankton distributions due to the increasing human activity in fish habitats and the need for distribution predictions that could potentially improve field coverage of ichthyoplankton. METHODOLOGY/PRINCIPAL FINDINGS: A system has been developed for operational simulation of ichthyoplankton distributions. We have coupled a two-day ocean forecasts from the Norwegian Meteorological Institute with an individual-based ichthyoplankton model for Northeast Arctic cod and Norwegian Spring Spawning herring producing daily updated maps of ichthyoplankton distributions. Recent years observed spawning distribution and intensity have been used as input to the model system. The system has been running in an operational mode since 2008. Surveys are expensive and distributions of early stages are therefore only covered once or twice a year. Comparison between model and observations are therefore limited in time. However, the observed and simulated distributions of juvenile fish tend to agree well during early fall. Area-overlap between modeled and observed juveniles September 1(st range from 61 to 73%, and 61 to 71% when weighted by concentrations. CONCLUSIONS/SIGNIFICANCE: The model system may be used to evaluate the design of ongoing surveys, to quantify the overlap with harmful substances in the ocean after accidental spills, as well as management planning of particular risky operations

  1. Atlantic menhaden adult tagging study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Atlantic menhaden are a schooling forage fish species, which are subject to a large commercial purse seine fishery. Atlantic menhaden are harvested for reduction...

  2. Atlantic Seaduck Project

    Science.gov (United States)

    Perry, M.C.; Hanson, Alan; Kerekes, Joseph; Paquet, Julie

    2006-01-01

    Atlantic Seaduck Project is being conducted to learn more about the breeding and moulting areas of seaducks in northern Canada and more about their feeding ecology on wintering areas, especially Chesapeake Bay. Satellite telemetry is being used to track surf scoters wintering in Chesapeake Bay, Maryland and black scoters on migrational staging areas in New Brunswick, Canada to breeding and moulting areas in northern Canada. Various techniques used to capture the scoters included mist netting, night-lighting, and net capture guns. All captured ducks were transported to a veterinary hospital where surgery was conducted following general anaesthesia procedures. A PTT100 transmitter (39 g) manufactured by Microwave, Inc., Columbia, Maryland was implanted into the duck?s abdominal cavity with an external (percutaneous) antenna. Eight of the surf scoters from Chesapeake Bay successfully migrated to possible breeding areas in Canada and all 13 of the black scoters migrated to suspected breeding areas. Ten of the 11 black scoter males migrated to James Bay presumably for moulting. Updated information from the ARGOS Systems aboard the NOAA satellites on scoter movements was made accessible on the Patuxent Website. Habitat cover types of locations using GIS (Geographical Information Systems) and aerial photographs (in conjunction with remote sensing software) are currently being analyzed to build thematic maps with varying cosmetic layer applications. Many factors related to human population increases have been implicated in causing changes in the distribution and abundance of wintering seaducks. Analyses of the gullet (oesophagus and proventriculus) and the gizzard of seaducks are currently being conducted to determine if changes from historical data have occurred. Scoters in the Bay feed predominantly on the hooked mussel and several species of clams. The long-tailed duck appears to select the gem clam in greater amounts than other seaducks, but exhibits a diverse diet of

  3. Using Clumped Isotopes to Understand Early Diagenetic Processes in Carbonate Microbialites of Mid-Cretaceous Codó Formation, NE Brazil

    Science.gov (United States)

    Bahniuk, A. M.; Vasconcelos, C.; McKenzie, J. A.; Franca, A. B.; Matsuda, N.; Eiler, J.

    2010-12-01

    Recent studies of the sedimentological, stratigraphic and geochemical aspects of carbonate microbialites have been carried out to characterize the paleoenvironmental and hydrological conditions of deposition for the Aptian Codó Formation (Parnaíba Basin) and the time-equivalent Santana Formation (Araripe Basin). This environmental interpretation is of interest because these sediments record the early stages of the opening of the Equatorial Atlantic Ocean, as well as being potentially important reservoir rock. Specifically, clumped isotope thermometry has been applied to evaluate the growth temperatures of carbonate components in selected samples from both outcrop and drill core. Preliminary results of clumped isotope measurements provide paleotemperatures derived for dense stromatolitic fabrics drilled from outcrop samples of the Codó Formation which vary between 29 and 33°C. In contrast, the micritic matrix of the drill core samples of the Codó Formation indicates a temperature range from 30 to 48°C. The lower values for the outcrop samples may represent a primary or early diagenetic temperature signal preserved in the rock. Moreover, the micritic matrix from the Santana Formation drill core samples indicates paleotemperatures ranging from 40 to 68°C, which are slightly higher than those for all measured samples of the Codó Formation. We propose that the higher paleotemperatures for all drill core samples denote a diagenetic effect that occurred with sediment lithification processes during burial; that is, isotopic reequilibration at depth is reflected in the higher measured paleotemperatures. Increased paleotemperatures are probably present in some carbonate fabrics of the outcrop samples of the Codo Formation, which also underwent lithification, but this signal was missed by our inability to micro-sample primary or early diagenetic stromatolitic fabrics. Assuming that the outcrop samples of the Codó Formation preserve an original stable isotope signal

  4. Hydrolysis of Marine Cod (Gadus Morhua) Head - Utilization of rest raw material from cod for production of ingredients for human consumption

    OpenAIRE

    Meldstad, Fataneh

    2015-01-01

    The main objective of this study was to determine the possibility of utilizing frozen marine cod head for further processing into high-quality and high-yield fish protein hydrolysates. The project included determination of the effect of mincing versus whole head, frozen storage and thawing methods on the composition and yield of FPH. The results show that freezing and thawing of cod head lead to small changes in the composition of raw material and consequently the resulting ...

  5. Ingestion of bacteria by cod (Gadus morhua L.) larvae. In: The propagation of cod Gadus morhua L.: an international symposium, Arendal, 14 - 17 June 1983

    OpenAIRE

    Olafsen, Jan A.

    1984-01-01

    The uptake of Rhodamine-labelled bacteria by cod larvae was demonstrated using a fluorescent microscopy technique, which allowed a quick estimate of bacterial uptake and gut clearance. Live or heat-killed bacteria, isolated from cod-eggs, were rapidly ingested by larvae at yolk-sac and older stages. A substantial uptake could be seen after 15 min exposure, and eventually the bacteria became densely packed in the digestive tract. Some morphological details in the develo...

  6. Plastic ingestion by juvenile polar cod (Boreogadus saida) in the Arctic Ocean

    NARCIS (Netherlands)

    Kühn, Susanne; Schaafsma, Fokje L.; Werven, van Bernike; Flores, Hauke; Bergmann, Melanie; Egelkraut-Holtus, Marion; Tekman, Mine B.; Franeker, van Jan A.

    2018-01-01

    One of the recently recognised stressors in Arctic ecosystems concerns plastic litter. In this study, juvenile polar cod (Boreogadus saida) were investigated for the presence of plastics in their stomachs. Polar cod is considered a key species in the Arctic ecosystem. The fish were collected both

  7. 77 FR 59970 - Notice of November 14, 2012, Meeting for Cape Cod National Seashore Advisory Commission

    Science.gov (United States)

    2012-10-01

    ... change Herring Cove Beach/revetment Climate Friendly Parks 6. Old Business National Seashore Law Enforcement Policies 7. New Business 8. Date and agenda for next meeting 9. Public comment and 10. Adjournment... Meeting of the Cape Cod National Seashore Advisory Commission. DATES: The public meeting of the Cape Cod...

  8. Increasing intake of soybean protein or casein, but not cod meal, reduces nephrocalcinosis in female rats.

    NARCIS (Netherlands)

    Zhang, X.; Beynen, A.C.

    1992-01-01

    Female weanling rats were fed diets with soybean protein, casein or cod meal at 171, 342 or 513 mmol nitrogen/100 g for 3 wk. The diets were isonitrogenous and balanced for fat, cholesterol, calcium, magnesium and phosphorus. Cod meal feeding at 171 and 342 mmol nitrogen/100 g diet produced lower

  9. Prediction of selectivity from morphological conditions: Methodology and a case study on cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Herrmann, Bent; Krag, Ludvig Ahm; Frandsen, Rikke

    2009-01-01

    The FISHSELECT methodology. tools, and software were developed and used to measure the morphological parameters that determine the ability of cod to penetrate different mesh types, sizes, and openings. The shape of one cross-section at the cod's head was found to explain 97.6% of the mesh...

  10. [Cod liver oil. A natural Vitamin D for preserving health].

    Science.gov (United States)

    Fehér, János; Kovács, Illés; Corrado, Balacco-Gabrieli

    2011-02-27

    Vitamin D deficiency is pandemic in industrialized countries due to life-style changes. Recent studies suggest that besides bone-metabolism, vitamin D plays a central role in basic cell function like multiplication, differentiation and metabolism. This may explain that low vitamin D levels represent a risk factor for several apparently different diseases such as infective, autoimmune, neurodegenerative and cardiovascular diseases, as well as diabetes, osteoporosis and cancer. Accumulating evidences suggest that an adequate intake of vitamin D may significantly decrease prevalence and clinical outcome of these diseases. Estimated reduction of the economic burden might reach about 10 percent through normalizing vitamin D levels for these diseases. However, high doses of vitamin D monotherapy needs precaution for potential adverse effects and it should be substituted with the recommended doses of vitamin D in combination with synergistic vitamin A and omega 3 fatty acids, such as cod liver oil.

  11. Biodegradation of COD in Household Wastewater with Aerobic Biofilm Technology by Adding Sediment Drainage Sewerage

    Science.gov (United States)

    Sumiyati, Sri; Purwanto; Sutrisno, Endro; Sudarno; Arthawidya, Jalu; Izzudin, Humam

    2018-02-01

    Household wastewater contains contaminants that harm the environment. One of the pollutants found COD. If being discharged into the environment directly, COD concentrations exceeding the existing quality standard will disrupt the ecosystem in the receiving water body. One of the technologies that can degrade COD is biofilm technology with honeycomb tube media. This research aims to analyze the decrease of COD concentration present in wastewater household with biofilm technology of honeycomb media. The reactor used in was made of glass with a thickness of 4 mm, a volume of 18 litres and operated continuously. The media used is made of a PVC pipe, cut to 3 cm in size and then glued to one another, forming a honey comb. The results showed that there has been a decrease in COD concentration of household wastewater.

  12. Association between nematode Hysterothylacium aduncum invasion of cod larvae and growth

    DEFF Research Database (Denmark)

    Mehrdana, Foojan; Bahlool, Qusay Z. M.; Kuhn, Jesper

    , lapillus otoliths were removed, polished and the number of growth zones in each otolith counted by light microscopy. Each growth zone indicates one day of the fish life span. Covariance analysis demonstrated highly significant differences (p≤ 0.001) between the growth rate of infected and uninfected cod...... invertebrates and fish species and for some species also higher vertebrate hosts. We have recently demonstrated that fry of North Sea cod has a high prevalence of infection with regard to the nematode Hysterothylacium aduncum and it was indicated that these infections could affect survival of cod and thereby...... affect the cod stock in the North Sea. The objective of the present study was to elucidate if infections are associated with a decrease or an increase of fish size when examining fish of the same age. We investigated effects of H. aduncum infections on the growth rate of cod larvae by using the otolith...

  13. Self-reported chemicals exposure, beliefs about disease causation, and risk of breast cancer in the Cape Cod Breast Cancer and Environment Study: a case-control study

    OpenAIRE

    Zota, Ami R; Aschengrau, Ann; Rudel, Ruthann A; Brody, Julia

    2010-01-01

    Abstract Background Household cleaning and pesticide products may contribute to breast cancer because many contain endocrine disrupting chemicals or mammary gland carcinogens. This population-based case-control study investigated whether use of household cleaners and pesticides increases breast cancer risk. Methods Participants were 787 Cape Cod, Massachusetts, women diagnosed with breast cancer between 1988 and 1995 and 721 controls. Telephone interviews asked about product use, beliefs abou...

  14. Structural and biophysical analysis of interactions between cod and human uracil-DNA N-glycosylase (UNG) and UNG inhibitor (Ugi)

    Energy Technology Data Exchange (ETDEWEB)

    Assefa, Netsanet Gizaw [UiT The Arctic University of Norway, 9037 Tromsø (Norway); Niiranen, Laila [UiT The Arctic University of Norway, 9037 Tromsø (Norway); University of Turku, FIN-20014 Turku (Finland); Johnson, Kenneth A.; Leiros, Hanna-Kirsti Schrøder; Smalås, Arne Oskar; Willassen, Nils Peder [UiT The Arctic University of Norway, 9037 Tromsø (Norway); Moe, Elin, E-mail: elin.moe@uit.no [UiT The Arctic University of Norway, 9037 Tromsø (Norway); Universidade Nova de Lisboa, Avenida da Republica (EAN), 2780-157 Oeiras (Portugal)

    2014-08-01

    A structural and biophysical study of the interactions between cod and human uracil-DNA N-glycosylase (UNG) and their inhibitor Ugi is presented. The stronger interaction between cod UNG and Ugi can be explained by a greater positive electrostatic surface potential. Uracil-DNA N-glycosylase from Atlantic cod (cUNG) shows cold-adapted features such as high catalytic efficiency, a low temperature optimum for activity and reduced thermal stability compared with its mesophilic homologue human UNG (hUNG). In order to understand the role of the enzyme–substrate interaction related to the cold-adapted properties, the structure of cUNG in complex with a bacteriophage encoded natural UNG inhibitor (Ugi) has been determined. The interaction has also been analyzed by isothermal titration calorimetry (ITC). The crystal structure of cUNG–Ugi was determined to a resolution of 1.9 Å with eight complexes in the asymmetric unit related through noncrystallographic symmetry. A comparison of the cUNG–Ugi complex with previously determined structures of UNG–Ugi shows that they are very similar, and confirmed the nucleotide-mimicking properties of Ugi. Biophysically, the interaction between cUNG and Ugi is very strong and shows a binding constant (K{sub b}) which is one order of magnitude larger than that for hUNG–Ugi. The binding of both cUNG and hUNG to Ugi was shown to be favoured by both enthalpic and entropic forces; however, the binding of cUNG to Ugi is mainly dominated by enthalpy, while the entropic term is dominant for hUNG. The observed differences in the binding properties may be explained by an overall greater positive electrostatic surface potential in the protein–Ugi interface of cUNG and the slightly more hydrophobic surface of hUNG.

  15. EPISODIC EOLIAN SAND DEPOSITION IN THE PAST 4000 YEARS IN CAPE COD NATIONAL SEASHORE, MASSACHUSETTS, USA IN RESPONSE TO POSSIBLE HURRICANE/STORM AND ANTHROPOGENIC DISTURBANCES

    Directory of Open Access Journals (Sweden)

    Steven L. Forman

    2015-02-01

    Full Text Available The eolian sand depositional record for a dune field within Cape Cod National Seashore, Massachusetts is posit as a sensitive indicator of environmental disturbances in the late Holocene from a combination of factors such as hurricane/storm and forest fire occurrence, and anthropogenic activity. Stratigraphic and sedimentologic observations, particularly the burial of spodosol-like soils, and associated 14C and OSL ages that are concordant indicate at least six eolian depositional events at ca. 3750, 2500, 1800, 960, 430 and <250 years ago. The two oldest events are documented at just one locality and thus, the pervasiveness of this eolian activity is unknown. However, the four younger events are identified in three or more sites and show evidence for dune migration and sand sheet accretion. The timing of eolian deposition, particularly the initiation age, corresponds to documented periods of increased storminess/hurricane activity in the North Atlantic Ocean at ca. 2.0 to 1.6, and 1.0 ka and also a wetter coastal climate, which suppressed the occurrence of forest fire. Thus, local droughts are not associated with periods of dune movement in this mesic environment. Latest eolian activity on outer Cape Cod commenced in the past 300 to 500 years and may reflect multiple factors including broad-scale landscape disturbance with European colonization, an increased incidence of forest fires and heightened storminess. Eolian systems of Cape Cod appear to be sensitive to landscape disturbance and prior to European settlement may reflect predominantly hurricane/storm disturbance, despite generally mesic conditions in past 4 ka.

  16. Forests and People in the Mid-Atlantic Region

    Science.gov (United States)

    Stephanie Fulton; Evan Mercer; M. Patricia Bradley

    2012-01-01

    Human populations in the Mid-Atlantic region over the last 250 years have increased nearly 100-fold, from an estimated few hundred thousand people to over 30 million people (Mercer and Murthy 2000). Increased population growth usually results in the conversion of forestland to nonforest uses, particularly agriculture, pastureland, and urban development. Not only is the...

  17. Slave to the rhythm: seasonal signals in otolith microchemistry reveal age of eastern Baltic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Hüssy, Karin; Gröger, J.; Heidemann, F.

    2016-01-01

    Annual growth zones in cod otoliths from the eastern Baltic stock are less discrete than in other cod stocks leading to biased age reading, which recently led to a failure of age-based assessment in the eastern Baltic cod stock. In this study, we explored the applicability of minor and trace elem...

  18. 75 FR 19561 - Fisheries of the Economic Exclusive Zone Off Alaska; Pacific Cod in the Bering Sea and Aleutian...

    Science.gov (United States)

    2010-04-15

    ... is opening directed fishing for Pacific cod by catcher vessels less than 60 feet (18.3 meters) length... meters) length overall using hook-and-line or pot gear in the BSAI under Sec. 679.20(d)(1)(iii) on March... 400 metric tons of Pacific cod remain in the 2010 Pacific cod apportionment for catcher vessels less...

  19. Thawed cod fillets spoil less rapidly than unfrozen fillets when stored under modified atmosphere at 2 C

    DEFF Research Database (Denmark)

    Guldager, H.S.; Bøknæs, Niels; Østerberg, Carsten

    1998-01-01

    The effect of two months of frozen storage at -20 degrees C on the spoilage characteristics and shelf life of thawed and modified atmosphere packed (MAP) cod fillets stored at 2 degrees C was studied. Thawed MAP cod fillets were compared with fresh cod fillets stored in CO2-containing modified at...

  20. Age, growth rate, and otolith growth of polar cod (Boreogadus saida in two fjords of Svalbard, Kongsfjorden and Rijpfjorden

    Directory of Open Access Journals (Sweden)

    Dariusz P. Fey

    2017-10-01

    Full Text Available This work presents biological information for polar cod (Boreogadus saida collected with a Campelen 1800 shrimp bottom trawl in Kongsfjorden (two stations located in the inner part of the fjord adjacent to the glacier and Rijpfjorden (one station at the entrance to the fjord in September and October 2013. The otolith-based ages of polar cod collected in Kongsfjorden (6.1–24 cm total length TL; n = 813 ranged from 0 to 4 years. The growth rate was relatively constant at approximately 4.7 cm year−1 between years 1 and 4, which indicates that growth was fast in the glacier area. The ages of polar cod collected in Rijpfjorden (8.6–15.9 cm TL; n = 64 ranged from 2 to 3 years. The fish from Rijpfjorden were smaller at age than those from Kongsfjorden, and their growth rate between years 2 and 3 (no other age classes were available was approximately 3.3 cm year−1. In both fjords, males and females were of the same size-at-age and the same weight-at-TL. The small sampling area means that the results on growth rate are not representative of the entire fjords. Instead, the results can be discussed as presenting the possible growth rates of some populations. A strong relationship was identified between otolith size (length and weight and fish size (TL and TW, with no differences between males and females or the fjords. A significant, strong relationship was also noted between fish and otolith growth rates.

  1. Inversion of CDOM and COD in water using HJ-1/CCD data

    International Nuclear Information System (INIS)

    Huang, Miaofen; Xing, Xufeng; Zhao, Zulong; Li, Zhanqiang; Wang, Xinxing

    2014-01-01

    With the in-situ measurement data including the absorption coefficient of the CDOM, apparent optical properties and the COD, a regression model was established for retrieving ag(440) based on the remote sensing reflectance of the first and the third band of the environment satellite HJ-1/CCD. The measurement data were obtained at the regions of Panjin, Liaoning province in May 2008 and August 2009. Secondly, the remote sensing regression model was created based on the correlation of the CDOM optical properties and the COD. Finally, using the HJ-1/CCD data from 2009 to 2011 in Liaodong bay, the thematic snapshots of water environmental parameters in coastal waters, such as the CDOM and the COD, were calculated and analyzed. The results showed that: (1) the distribution of the CDOM tends to decrease from offshore areas to distant sea with some zonated character; (2) Most of the retrieved CDOM values vary between 0.2–1.7m-1, which is consistent with the measured value in 2009 and 2010 years; (3) the spatial distribution of the COD has good consistency with the CDOM, also shows a certain zonated distribution in coastal-offshore areas; (4) in September 2009 and September 2011, the values of the COD was basically below 40 mg/L while the values of the COD in September 2010 are relatively higher, mostly above 55 mg/L; (5) in June 2011 and May 2010, the COD values are nearly all larger than 55 mg/L

  2. Multilocus Bayesian Estimates of Intra-Oceanic Genetic Differentiation, Connectivity, and Admixture in Atlantic Swordfish (Xiphias gladius L..

    Directory of Open Access Journals (Sweden)

    Brad L Smith

    Full Text Available Previous genetic studies of Atlantic swordfish (Xiphias gladius L. revealed significant differentiation among Mediterranean, North Atlantic and South Atlantic populations using both mitochondrial and nuclear DNA data. However, limitations in geographic sampling coverage, and the use of single loci, precluded an accurate placement of boundaries and of estimates of admixture. In this study, we present multilocus analyses of 26 single nucleotide polymorphisms (SNPs within 10 nuclear genes to estimate population differentiation and admixture based on the characterization of 774 individuals representing North Atlantic, South Atlantic, and Mediterranean swordfish populations. Pairwise FST values, AMOVA, PCoA, and Bayesian individual assignments support the differentiation of swordfish inhabiting these three basins, but not the current placement of the boundaries that separate them. Specifically, the range of the South Atlantic population extends beyond 5°N management boundary to 20°N-25°N from 45°W. Likewise the Mediterranean population extends beyond the current management boundary at the Strait of Gibraltar to approximately 10°W. Further, admixture zones, characterized by asymmetric contributions of adjacent populations within samples, are confined to the Northeast Atlantic. While South Atlantic and Mediterranean migrants were identified within these Northeast Atlantic admixture zones no North Atlantic migrants were identified respectively in these two neighboring basins. Owing to both, the characterization of larger number of loci and a more ample spatial sampling coverage, it was possible to provide a finer resolution of the boundaries separating Atlantic swordfish populations than previous studies. Finally, the patterns of population structure and admixture are discussed in the light of the reproductive biology, the known patterns of dispersal, and oceanographic features that may act as barriers to gene flow to Atlantic swordfish.

  3. Ribosomal RNA gene sequences confirm that protistan endoparasite of larval cod Gadus morhua is Ichthyodinium sp

    DEFF Research Database (Denmark)

    Skovgaard, Alf; Meyer, Stefan; Overton, Julia Lynne

    2010-01-01

    An enigmatic protistan endoparasite found in eggs and larvae of cod Gadus morhua and turbot Psetta maxima was isolated from Baltic cod larvae, and DNA was extracted for sequencing of the parasite's small Subunit ribosomal RNA (SSU rRNA) gene. The endoparasite has previously been suggested...... to be related to Ichthyodinium chabelardi, a dinoflagellate-like protist that parasitizes yolk sacs of embryos and larvae of a variety of fish species. Comparison of a 1535 bp long fragment of the SSU rRNA gene of the cod endoparasite showed absolute identify with I. chabelardi, demonstrating that the 2...

  4. Sensory characteristics of different cod products related to consumer preferences and attitudes

    DEFF Research Database (Denmark)

    Sveinsdottir, K.; Martinsdottir, E.; Green-Petersen, Ditte

    2009-01-01

    countries tasted and scored the cod products on a 9-point hedonic scale. In addition information on the consumers attitudes, motives/barriers and fish purchase behaviour was collected. The aim was to investigate how sensory quality corresponded to consumers liking of different cod products and to study...... to fish consumption, attitudes and preferences of the eight cod products. However, it was demonstrated that within each country, different segments of consumers existed with different preferences, motives/barriers and demographic background. The results indicated various potential to increase fish...

  5. Developing Baltic cod recruitment models II : Incorporation of environmental variability and species interaction

    DEFF Research Database (Denmark)

    Köster, Fritz; Hinrichsen, H.H.; St. John, Michael

    2001-01-01

    We investigate whether a process-oriented approach based on the results of field, laboratory, and modelling studies can be used to develop a stock-environment-recruitment model for Central Baltic cod (Gadus morhua). Based on exploratory statistical analysis, significant variables influencing...... cod in these areas, suggesting that key biotic and abiotic processes can be successfully incorporated into recruitment models....... survival of early life stages and varying systematically among spawning sites were incorporated into stock-recruitment models, first for major cod spawning sites and then combined for the entire Central Baltic. Variables identified included potential egg production by the spawning stock, abiotic conditions...

  6. Threshold-dependent climate effects and high mortality limit recruitment and recovery of the Kattegat cod

    DEFF Research Database (Denmark)

    Lindegren, Martin; Eero, Margit

    2013-01-01

    Cod in the Kattegat is one of the most dramatic examples of stock collapse, where despite large management efforts, almost no signs of recovery have been observed. We investigate how multiple physical and biological factors could potentially influence recruitment and recovery of Kattegat cod, using...... non-additive threshold models. In contrast to previous studies on recruitment dynamics of Kattegat cod Gadus morhua, we found that recruitment variability may be explained by a combination of the size of the spawning stock and external conditions (i.e. sea surface temperature and oxygen concentrations...

  7. Bioactivity of Cod and Chicken Protein Hydrolysates before and after in vitro Gastrointestinal Digestion

    DEFF Research Database (Denmark)

    Jamnik, Polona; Istenič, Katja; Wulff, Tune

    2017-01-01

    , where values of cod and chicken were (95.5±1.2) and (90.5±0.7) %, respectively. Neither species nor digestion had any effect on cellular metabolic energy. At proteome level, digested hydrolysates gave again significantly stronger responses than undigested counterparts; cod peptides here also gave...... somewhat stronger response than chicken peptides. The knowledge of the action of food protein hydrolysates and their digests within live cells, also at proteome level, is important for further validation of their activity in higher eukaryotes to develop new products, such as in this case chicken and cod...... muscle-derived peptides as functional ingredients....

  8. Significance of Charpy and COD tests in the determination of fracture toughness of welds

    International Nuclear Information System (INIS)

    Caminha Junior, H.M.; Bastian, F.L.

    1983-01-01

    A comparison is made between the Charpy and crack opening displacement (COD) tests used to acess the fracture toughness of metallic materials. The main problems inherent in these tests are discussed, such as scatter of results and their advantages and limitations. The chief experimental difficulties when they are applied to welds are indicated and the various methods available for calculating the COD from a test graph are described. Comments are made on the use of the Charpy test and the methods of calculating the COD in determing critical defect sizes in welded structures. (Author) [pt

  9. Specific inhibition of Photobacterium phosphoreum extends the shelf life of modified-atmosphere-packed cod fillets

    DEFF Research Database (Denmark)

    Dalgaard, Paw; Munoz, L.G.; Mejlholm, Ole

    1998-01-01

    rather than the development of a new product. In naturally contaminated modified-atmosphere-packed cod fillets, 500 ppm Na(2)CaEDTA reduced the growth rate of P. phosphoreum by 40% and shelf life was increased proportionally by 40%, from 15 to 17 days to 21 to 23 days at 0 degrees C. In aerobically...... stored cod fillets other microorganisms were responsible for spoilage and Na2CaEDTA had no effect on shelf Life. The extension of the shelf life of modified-atmosphere-packed cod therefore was a result of the reduced growth of P. phosphoreum and no other microbial or nonmicrobial spoilage reactions...

  10. Surface elevation dynamics in vegetated Spartina marshes versus unvegetated tidal ponds along the mid-Atlantic coast, USA, with implications to waterbirds

    Science.gov (United States)

    Erwin, R. Michael; Cahoon, Donald R.; Prosser, Diann J.; Sanders, Geoffrey; Hensel, Philippe

    2006-01-01

    Mid Atlantic coastal salt marshes contain a matrix of vegetation diversified by tidal pools, pannes, and creeks, providing habitats of varying importance to many species of breeding, migrating, and wintering waterbirds. We hypothesized that changes in marsh elevation were not sufficient to keep pace with those of sea level in both vegetated and unvegetated Spartina alterniflora sites at a number of mid lagoon marsh areas along the Atlantic coast. We also predicted that northern areas would suffer less of a deficit than would southern sites. Beginning in August 1998, we installed surface elevation tables at study sites on Cape Cod, Massachusetts, southern New Jersey, and two locations along Virginia's eastern shore. We compared these elevation changes over the 4-4.5 yr record with the long-term (> 50 yr) tidal records for each locale. We also collected data on waterbird use of these sites during all seasons of the year, based on ground surveys and replicated surveys from observation platforms. Three patterns of marsh elevation change were found. At Nauset Marsh, Cape Cod, the Spartina marsh surface tracked the pond surface, both keeping pace with regional sea-level rise rates. In New Jersey, the ponds are becoming deeper while marsh surface elevation remains unchanged from the initial reading. This may result in a submergence of the marsh in the future, assuming sea-level rise continues at current rates. Ponds at both Virginia sites are filling in, while marsh surface elevation rates do not seem to be keeping pace with local sea-level rise. An additional finding at all sites was that subsidence in the vegetated marsh surfaces was less than in unvegetated areas, reflecting the importance of the root mat in stabilizing sediments. The implications to migratory waterbirds are significant. Submergence of much of the lagoonal marsh area in Virginia and New Jersey over the next century could have major negative (i.e., flooding) effects on nesting populations of marsh

  11. Delineation of groundwater recharge areas, western Cape Cod, Massachusetts

    Science.gov (United States)

    Masterson, John P.; Walter, Donald A.

    2000-01-01

    The unconfined sand-and-gravel aquifer in western Cape Cod, Massachusetts, which is the sole source of water supply for the communities in the area, is recharged primarily from precipitation. The rate of recharge from precipitation is estimated to be about 26 inches per year (in/yr), or about 60 percent of the precipitation rate. This recharge rate yields a flow through the aquifer of about 180 million gallons per day (Mgal/d). Groundwater flows radially outward from the top of the water-table mound in the north-central part of the flow system toward the coast, as indicated by the water-table contours on the large map on this sheet. Recharge that reaches the water table near the top of the mound travels deeper through the aquifer than recharge that reaches the water table closer to the coast. All recharge to the aquifer ultimately discharges to pumping wells, streams, or coastal areas; however, some of this recharge may flow first through kettle ponds before eventually reaching these discharge points.

  12. A microsatellite baseline for genetic stock identification of European Atlantic salmon (Salmo salar L.)

    DEFF Research Database (Denmark)

    Gilbey, John; Coughlan, Jamie; Wennevik, Vidar

    2018-01-01

    Atlantic salmon (Salmo salar L.) populations from different river origins mix in the North Atlantic during the marine life stage. To facilitate marine stock identification, we developed a genetic baseline covering the European component of the species' range excluding the Baltic Sea, from the Rus...

  13. Atlantic Basin refining profitability

    International Nuclear Information System (INIS)

    Jones, R.J.

    1998-01-01

    A review of the profitability margins of oil refining in the Atlantic Basin was presented. Petroleum refiners face the continuous challenge of balancing supply with demand. It would appear that the profitability margins in the Atlantic Basin will increase significantly in the near future because of shrinking supply surpluses. Refinery capacity utilization has reached higher levels than ever before. The American Petroleum Institute reported that in August 1997, U.S. refineries used 99 per cent of their capacity for several weeks in a row. U.S. gasoline inventories have also declined as the industry has focused on reducing capital costs. This is further evidence that supply and demand are tightly balanced. Some of the reasons for tightening supplies were reviewed. It was predicted that U.S. gasoline demand will continue to grow in the near future. Gasoline demand has not declined as expected because new vehicles are not any more fuel efficient today than they were a decade ago. Although federally-mandated fuel efficiency standards were designed to lower gasoline consumption, they may actually have prevented consumption from falling. Atlantic margins were predicted to continue moving up because of the supply and demand evidence: high capacity utilization rates, low operating inventories, limited capacity addition resulting from lower capital spending, continued U.S. gasoline demand growth, and steady total oil demand growth. 11 figs

  14. The effect of temperature and body size on metabolic scope of activity in juvenile Atlantic cod Gadus morhua L

    DEFF Research Database (Denmark)

    Tirsgaard, Bjørn; Behrens, Jane; Steffensen, John Fleng

    2015-01-01

    Changes in ambient temperature affect the physiology and metabolism and thus the distribution of fish. In this study we used intermittent flow respirometry to determine the effect of temperature (2, 5, 10, 15 and 20 °C) and wet body mass (BM) (~30–460 g) on standard metabolic rate (SMR, mg O2 h−1...

  15. Influences of potential predictor variables on gastric evacuation in Atlantic cod Gadus morhua L. feeding on fish prey

    DEFF Research Database (Denmark)

    Andersen, Niels Gerner

    2012-01-01

    of photoperiod and pre-experimental treatment of prey were also tested. Freshly killed A. tobianus were evacuated from the stomach of G. morhua at a rate similar to the value estimated from conspecifics kept deep-frozen and subsequently thawed prior to the evacuation experiment. The evacuation rate in G. morhua...... exposed to continuous light did not differ from the rate obtained from fish maintained under a 12L:12D photoperiod. The evacuation rates estimated from the latter fish in the dark and light periods, respectively, were likewise similar. These results indicate that the resistance of prey to the digestive...

  16. An estrogen-responsive plasma protein expression signature in Atlantic cod (Gadus morhua) revealed by SELDI-TOF MS

    DEFF Research Database (Denmark)

    Nielsen, Mari Mæland; Meyer, Sonnich; Larsen, Bodil Katrine

    2011-01-01

    Compound-specific protein expression signatures( PESs) can be revealed by proteomic techniques. The SELDI-TOF MS approach is advantageous due to its simplicity and high-throughput capacity,however, there are concerns regarding the reproducibility of this method. The aim of this study was to define...

  17. THE EFFECT OF HYPOXIA ON THE MAXIMUM MATABOLIC RATE AND SPECIFIC DYNAMIC ACTION IN ATLANTIC COD Gadus morhua

    DEFF Research Database (Denmark)

    Steffensen, John Fleng

    2010-01-01

    John Fleng Steffensen' and Anders Drud Jordan Aquaculture 2010 - San Diego - Physiological Insights Towards Improving Fish Culture. Hypoxia is an increasing problem in coastal near areas and estuaries. Hypoxia can also be a problem in aquaculture systems with a high degree of recirculating water...... reduced the Scope for Activity by 55 % in nonnoxia. In hypoxia the effect was more pronounced with a 69 % reduction of the scope for activity. In conclusion hypoxia prolong the postabsorptive state of fi sh by limiting the peak metabolic rate, causing that less food is assimilated over a certain period...

  18. Reconstructing historical stock development of Atlantic cod (Gadus morhua) in the eastern Baltic Sea before the beginning of intensive exploitation

    DEFF Research Database (Denmark)

    Eero, Margit; Köster, Fritz; MacKenzie, Brian

    2008-01-01

    mortality before the 1940s was below 0.2, but reached moderate levels during the Second World War. The stock size before the war may be considered as a reference level of biomass at low fishing impact, providing important information for the management of fisheries and the Baltic ecosystem....

  19. Effect of fish length and nutritional condition on the fecundity of distressed Atlantic cod Gadus morhua from the Baltic Sea

    DEFF Research Database (Denmark)

    Mion, M.; Thorsen, A.; Vitale, F.

    2018-01-01

    for future fecundity studies on this stock. The results showed that FP was mainly positively related to fish length, but K and IH also contributed significantly to the variation in FP . The model predicted that fish with K = 1·2 have a FP 51% higher than fish of the same LT with K = 0·8. The prevalence...... of fecundity regulation by atresia was 5·8%, but it was found only in fish in the pre-spawning maturity stage and with low K. Temporal changes in biological features such as the length composition and individual body condition of eastern Baltic G. morhua, should be accounted for when estimating stock...

  20. Characterization of Francisella sp., GM2212, the first Francisella isolate from marine fish, Atlantic cod (Gadus morhua)

    DEFF Research Database (Denmark)

    Ottem, Karl F; Nylund, Are; Karlsbakk, Egil

    2007-01-01

    from F. tularensis and F. philomiragia. GM2212(T) is catalase-positive, indole positive, oxidase-negative, do not produce H(2)S in Triple Sugar Iron agar, and does not hydrolyze gelatin, is resistant to erythromycin and susceptible to ceftazidime, the latter five characteristics separating it from F...

  1. Between Localization and Delocalization: Ru(cod)2+ Units in the Zintl Clusters [Bi9 {Ru(cod)}2 ]3- and [Tl2 Bi6 {Ru(cod)}]2.

    Science.gov (United States)

    Lichtenberger, Niels; Spang, Nils; Eichhöfer, Andreas; Dehnen, Stefanie

    2017-10-16

    Reactions of [K(crypt-222)] 2 (TlBi 3 )⋅0.5 en (1 b) with [Ru(cod)(H 2 CC(Me)CH 2 ) 2 ] (A) in 1,2-diaminoethane (en) led to the formation of two compounds with new bismuth-rich cluster anions, [K(crypt-222)] 3 [Bi 9 {Ru(cod)} 2 ]⋅1.5 en (2) and [K(crypt-222)] 2 [Tl 2 Bi 6 {Ru(cod)}]⋅2 tol (3), alongside the salt of a binary nido cluster, [K(crypt-222)] 3 (Tl 4 Bi 5 )⋅2 en (4). The anions in 2 and 3 are two further examples of rare heterometallic clusters containing Ru atoms. As one cod ligand is retained on each Ru atom in both clusters, the anions may be viewed as intermediates on the way towards larger, ligand-free intermetalloid clusters. Quantum-chemical studies provided insight into the bonding situation in these clusters. According to these studies, the anion of 2 features both electron-precise and electron-deficient parts. Electrospray ionization mass spectrometry analysis indicated that the clusters undergo stepwise fragmentation. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Effect of the two-stage thermal disintegration and anaerobic digestion of sewage sludge on the COD fractions

    Directory of Open Access Journals (Sweden)

    Ciaciuch Anna

    2017-09-01

    Full Text Available The research presents the changes in chemical oxygen demand (COD fractions during the two-stage thermal disintegration and anaerobic digestion (AD of sewage sludge in municipal wastewater treatment plant (WWTP. Four COD fractions have been separated taking into account the solubility of substrates and their susceptibility to biodegradation: inert soluble organic matter SI, readily biodegradable substrate SS, slowly biodegradable substrates XS and inert particulate organic material XI. The results showed that readily biodegradable substrates SS (46.8% of total COD and slowly biodegradable substrates XS (36.1% of total COD were dominant in the raw sludge effluents. In sewage effluents after two-stage thermal disintegration, the percentage of SS fraction increased to 90% of total COD and percentage of XS fraction decreased to 8% of total COD. After AD, percentage of SS fraction in total COD decreased to 64%, whereas the percentage of other fractions in effluents increased.

  3. Long term operation of continuous-flow system with enhanced biological phosphorus removal granules at different COD loading.

    Science.gov (United States)

    Li, Dong; Lv, Yufeng; Zeng, Huiping; Zhang, Jie

    2016-09-01

    In this study, a continuous-flow system with enhanced biological phosphorus removal (EBPR) granules was operated at different COD concentrations (200, 300 and 400mgL(-)(1)) to investigate the effect of COD loading on this system. The results showed that when the COD concentration in influent was increased to 400mgL(-)(1), the anaerobic COD removal efficiency and total phosphorus removal efficiency reduced obviously and the settling ability of granules deteriorated due to the proliferation of filamentous bacteria. Moreover, high COD loading inhibited the EPS secretion and destroyed the stability of granules. Results of high-through pyrosequencing indicated that filamentous bacteria had a competitive advantage over polyphosphate-accumulating organisms (PAOs) at high COD loading. The performance of system, settling ability of granules and proportion of PAOs gradually recovered to the initial level after the COD concentration was reduced to 200mgL(-)(1) on day 81. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Atlantic Oceanographic and Meteorological Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Atlantic Oceanographic and Meteorological Laboratory conducts research to understand the physical, chemical, and biological characteristics and processes of the...

  5. Radiological assessment of the impact on human populations and the environment of the 1949 to 1982 dumping of low and intermediate level radioactive waste in the deep North-East Atlantic

    International Nuclear Information System (INIS)

    Chartier, M.; Menard, F.

    1990-12-01

    A thorough radiological assessment of the impact of the 1949 to 1982 dumping of low- and intermediate- level radioactive waste in the deep North-East Atlantic is performed with the numerical compartmental REJMAR model. The calculations include the assessment of the dose equivalent to the individuals of a theoretical critical group through a large set of pathways, and the collective dose to mankind through the ingestion pathways. The complete dumping performed in the deep North-East Atlantic is taken into account. The assumptions of biological short-circuit through marin food chains are tested. The order of magnitude of the dose delivered to marine organisms living near the dumping site is assessed [fr

  6. Research progress of on-line automatic monitoring of chemical oxygen demand (COD) of water

    Science.gov (United States)

    Cai, Youfa; Fu, Xing; Gao, Xiaolu; Li, Lianyin

    2018-02-01

    With the increasingly stricter control of pollutant emission in China, the on-line automatic monitoring of water quality is particularly urgent. The chemical oxygen demand (COD) is a comprehensive index to measure the contamination caused by organic matters, and thus it is taken as one important index of energy-saving and emission reduction in China’s “Twelve-Five” program. So far, the COD on-line automatic monitoring instrument has played an important role in the field of sewage monitoring. This paper reviews the existing methods to achieve on-line automatic monitoring of COD, and on the basis, points out the future trend of the COD on-line automatic monitoring instruments.

  7. 75 FR 64955 - Fisheries of the Northeastern United States; Northeast Multispecies Fishery; Correction to Cod...

    Science.gov (United States)

    2010-10-21

    ... GOM cod. By an administrative error, the inseason action published on September 27, 2010, reduced the... effectiveness would further disadvantage vessels subject to the lower trip limits implemented on September 27...

  8. AFSC/REFM: Pacific cod genetics in the Aleutian Islands 2004-2007

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Landscape genetics of Pacific cod Gadus macrocephalus within the Bering Sea and Aleutian Islands (BSAI) management area of Alaska was examined in samples from nine...

  9. AFSC/RACE/GAP/Nichol: Archival tag depth and temperature data from Pacific cod

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data from 250 recaptured (624 released) depth and temperature recording archival (data storage) tags attached to Pacific cod off Kodiak Island and in the eastern...

  10. Location of and post-mortem changes in some cytoskeletal proteins in pork and cod muscle

    DEFF Research Database (Denmark)

    Morrison, E.H.; Bremner, Allan; Purslow, P.P.

    2000-01-01

    The cytoskeletal proteins actin, nebulin, spectrin, desmin, vinculin and talin were labelled immunohistochemically in sections of muscle from commercially available pigs and cod (Gadus morhua) taken pre-rigor and from samples stored for several days. Actin, nebulin and spectrin gave similar...... labelling patterns in both pork and cod muscle which remained the same in stored samples. Desmin was intensely labelled at the cell boundaries and within the body of the cells in both pork and cod in the initial and the stored samples. Vinculin was readily labelled in pork muscle but showed only diffuse...... labelling in fish. Labelling for talin in pork muscle was intense at the sarcolemma but was not present in samples stored for 4 days. In contrast, the label for talin was concentrated at the myotendinous junction of the cod muscle throughout the storage period. These are the first reports of the detection...

  11. Effect of influent COD/SO4(2-) ratios on UASB treatment of a synthetic sulfate-containing wastewater.

    Science.gov (United States)

    Hu, Yong; Jing, Zhaoqian; Sudo, Yuta; Niu, Qigui; Du, Jingru; Wu, Jiang; Li, Yu-You

    2015-07-01

    The effect of the chemical oxygen demand/sulfate (COD/SO4(2-)) ratio on the anaerobic treatment of synthetic chemical wastewater containing acetate, ethanol, and sulfate, was investigated using a UASB reactor. The experimental results show that at a COD/SO4(2-) ratio of 20 and a COD loading rate of 25.2gCODL(-1)d(-1), a COD removal of as high as 87.8% was maintained. At a COD/SO4(2-) ratio of 0.5 (sulfate concentration 6000mgL(-1)), however, the COD removal was 79.2% and the methane yield was 0.20LCH4gCOD(-1). The conversion of influent COD to methane dropped from 80.5% to 54.4% as the COD/SO4(2-) ratio decreased from 20 to 0.5. At all the COD/SO4(2-) ratios applied, over 79.4% of the total electron flow was utilized by methane-producing archaea (MPA), indicating that methane fermentation was the predominant reaction. The majority of the methane was produced by acetoclastic MPA at high COD/SO4(2-) ratios and both acetoclastic and hydrogenthrophic MPA at low COD/SO4(2-) ratios. Only at low COD/SO4(2-) ratios were SRB species such as Desulfovibrio found to play a key role in ethanol degradation, whereas all the SRB species were found to be incomplete oxidizers at both high and low COD/SO4(2-) ratios. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Proxy measures of fitness suggest coastal fish farms can act as population sources and not ecological traps for wild gadoid fish.

    Directory of Open Access Journals (Sweden)

    Tim Dempster

    Full Text Available BACKGROUND: Ecological traps form when artificial structures are added to natural habitats and induce mismatches between habitat preferences and fitness consequences. Their existence in terrestrial systems has been documented, yet little evidence suggests they occur in marine environments. Coastal fish farms are widespread artificial structures in coastal ecosystems and are highly attractive to wild fish. METHODOLOGY/PRINCIPAL FINDINGS: To investigate if coastal salmon farms act as ecological traps for wild Atlantic cod (Gadus morhua and saithe (Pollachius virens, we compared proxy measures of fitness between farm-associated fish and control fish caught distant from farms in nine locations throughout coastal Norway, the largest coastal fish farming industry in the world. Farms modified wild fish diets in both quality and quantity, thereby providing farm-associated wild fish with a strong trophic subsidy. This translated to greater somatic (saithe: 1.06-1.12 times; cod: 1.06-1.11 times and liver condition indices (saithe: 1.4-1.8 times; cod: 2.0-2.8 times than control fish caught distant from farms. Parasite loads of farm-associated wild fish were modified from control fish, with increased external and decreased internal parasites, however the strong effect of the trophic subsidy overrode any effects of altered loads upon condition. CONCLUSIONS AND SIGNIFICANCE: Proxy measures of fitness provided no evidence that salmon farms function as ecological traps for wild fish. We suggest fish farms may act as population sources for wild fish, provided they are protected from fishing while resident at farms to allow their increased condition to manifest as greater reproductive output.

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

    Directory of Open Access Journals (Sweden)

    Matthew T Balazik

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

  14. Mercury Cycling in Salt Marsh Pond Ecosystems: Cape Cod, MA

    Science.gov (United States)

    Ganguli, P. M.; Gonneea, M. E.; Lamborg, C. H.; Kroeger, K. D.; Swarr, G.; Vadman, K. J.; Baldwin, S.; Brooks, T. W.; Green, A.

    2014-12-01

    We are measuring total mercury (HgT) and monomethylmercury (CH3Hg+ or MMHg) in pore water, surface water, and sediment cores from two salt marsh pond systems on the south shore of Cape Cod, MA to characterize the distribution of mercury species and to identify features that influence mercury speciation and transport. Sage Lot Pond is relatively undisturbed and has low nitrogen loading (12 kg ha-1 y-1). It is part of the Waquoit Bay National Estuarine Reserve and is surrounded by undeveloped wooded uplands. In contrast, Great Pond is highly impacted. Nitrogen loading to the site is elevated (600 kg ha-1 y-1) and the marsh is adjacent to a large residential area. In both systems, a 1 to 2 m organic-rich peat layer overlies the permeable sand aquifer. Groundwater in this region is typically oxic, where pore water within salt marsh peat is suboxic to anoxic. We hypothesize that redox gradients at the transition from the root zone to peat and at the peat-sand interface may provide habitat for MMHg-producing anaerobic bacteria. Preliminary results from a 2-m nearshore depth profile at Sage Lot Pond indicate HgT in groundwater within the sand aquifer occurred primarily in the > 0.2 μm fraction, with unfiltered concentrations exceeding 100 pM. Filtered (fraction of filtered HgT in peat pore water. Although MMHg in both groundwater and pore water remained around 1 pM throughout our depth profile, we observed an increase in sediment MMHg (0.3 to 1.6 μg/kg) at the peat-sand interface. MMHg comprised ~50% of the HgT concentration in pore water suggesting mercury in the salt marsh peat is biologically available.

  15. Impact of influent COD/N ratio on disintegration of aerobic granular sludge.

    Science.gov (United States)

    Luo, Jinghai; Hao, Tianwei; Wei, Li; Mackey, Hamish R; Lin, Ziqiao; Chen, Guang-Hao

    2014-10-01

    Disintegration of aerobic granular sludge (AGS) is a challenging issue in the long-term operation of an AGS system. Chemical oxygen demand (COD)-to-nitrogen (N) ratio (COD/N), often variable in industrial wastewaters, could be a destabilizing factor causing granule disintegration. This study investigates the impact of this ratio on AGS disintegration and identifies the key causes, through close monitoring of AGS changes in its physical and chemical characteristics, microbial community and treatment performance. For specific comparison, two lab-scale air-lift type sequencing batch reactors, one for aerobic granular and the other for flocculent sludge, were operated in parallel with three COD/N ratios (4, 2, 1) applied in the influent of each reactor. The decreased COD/N ratios of 2 and 1 strongly influenced the stability of AGS with regard to physical properties and nitrification efficiency, leading to AGS disintegration when the ratio was decreased to 1. Comparatively the flocculent sludge maintained relatively stable structure and nitrification efficiency under all tested COD/N ratios. The lowest COD/N ratio resulted in a large microbial community shift and extracellular polymeric substances (EPS) reduction in both flocculent and granular sludges. The disintegration of AGS was associated with two possible causes: 1) reduction in net tyrosine production in the EPS and 2) a major microbial community shift including reduction in filamentous bacteria leading to the collapse of granule structure. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Genetic factors have a major effect on growth, number of vertebrae and otolith shape in Atlantic herring (Clupea harengus).

    Science.gov (United States)

    Berg, Florian; Almeland, Oda W; Skadal, Julie; Slotte, Aril; Andersson, Leif; Folkvord, Arild

    2018-01-01

    Atlantic herring, Clupea harengus, have complex population structures. Mixing of populations is known, but the extent of connectivity is still unclear. Phenotypic plasticity results in divergent phenotypes in response to environmental factors. A marked salinity gradient occurs from Atlantic Ocean (salinity 35) into the Baltic Sea (salinity range 2-12). Herring from both habitats display phenotypic and genetic variability. To explore how genetic factors and salinity influence phenotypic traits like growth, number of vertebrae and otolith shape an experimental population consisting of Atlantic purebreds and Atlantic/Baltic F1 hybrids were incubated and co-reared at two different salinities, 16 and 35, for three years. The F1-generation was repeatedly sampled to evaluate temporal variation. A von Bertalanffy growth model indicated that reared Atlantic purebreds had a higher maximum length (26.2 cm) than Atlantic/Baltic hybrids (24.8 cm) at salinity 35, but not at salinity 16 (25.0 and 24.8 cm, respectively). In contrast, Atlantic/Baltic hybrids achieved larger size-at-age than the wild caught Baltic parental group. Mean vertebral counts and otolith aspect ratios were higher for reared Atlantic purebreds than Atlantic/Baltic hybrids, consistent with the differences between parental groups. There were no significant differences in vertebral counts and otolith aspect ratios between herring with the same genotype but raised in different salinities. A Canonical Analysis of Principal Coordinates was applied to analyze the variation in wavelet coefficients that described otolith shape. The first discriminating axis identified the differences between Atlantic purebreds and Atlantic/Baltic hybrids, while the second axis represented salinity differences. Assigning otoliths based on genetic groups (Atlantic purebreds vs. Atlantic/Baltic hybrids) yielded higher classification success (~90%) than based on salinities (16 vs. 35; ~60%). Our results demonstrate that otolith shape and

  17. Genetic factors have a major effect on growth, number of vertebrae and otolith shape in Atlantic herring (Clupea harengus.

    Directory of Open Access Journals (Sweden)

    Florian Berg

    Full Text Available Atlantic herring, Clupea harengus, have complex population structures. Mixing of populations is known, but the extent of connectivity is still unclear. Phenotypic plasticity results in divergent phenotypes in response to environmental factors. A marked salinity gradient occurs from Atlantic Ocean (salinity 35 into the Baltic Sea (salinity range 2-12. Herring from both habitats display phenotypic and genetic variability. To explore how genetic factors and salinity influence phenotypic traits like growth, number of vertebrae and otolith shape an experimental population consisting of Atlantic purebreds and Atlantic/Baltic F1 hybrids were incubated and co-reared at two different salinities, 16 and 35, for three years. The F1-generation was repeatedly sampled to evaluate temporal variation. A von Bertalanffy growth model indicated that reared Atlantic purebreds had a higher maximum length (26.2 cm than Atlantic/Baltic hybrids (24.8 cm at salinity 35, but not at salinity 16 (25.0 and 24.8 cm, respectively. In contrast, Atlantic/Baltic hybrids achieved larger size-at-age than the wild caught Baltic parental group. Mean vertebral counts and otolith aspect ratios were higher for reared Atlantic purebreds than Atlantic/Baltic hybrids, consistent with the differences between parental groups. There were no significant differences in vertebral counts and otolith aspect ratios between herring with the same genotype but raised in different salinities. A Canonical Analysis of Principal Coordinates was applied to analyze the variation in wavelet coefficients that described otolith shape. The first discriminating axis identified the differences between Atlantic purebreds and Atlantic/Baltic hybrids, while the second axis represented salinity differences. Assigning otoliths based on genetic groups (Atlantic purebreds vs. Atlantic/Baltic hybrids yielded higher classification success (~90% than based on salinities (16 vs. 35; ~60%. Our results demonstrate that

  18. Restoration practicesin Brazil's Atlantic rainforest.

    Science.gov (United States)

    Jorge Correa de Lima Palidon; Maisa dos Santos Guapyassu

    2005-01-01

    The atlantic Rain Forst (Mata Atlantica) extends along the southern coast of Brazil and inland into Argentina and Paraguay. Originally covering 15% of the land area of Brazil, it was a region of an estimated 1.3 million km2 (MMA 2000). Today, remnants of the Atlantic Forest represents about 8% of the original area, or some 94,000 km2...

  19. [Spatial distribution of COD and the correlations with other parameters in the northern region of Lake Taihu].

    Science.gov (United States)

    Zhang, Yun-lin; Yang, Long-yuan; Qin, Bo-qiang; Gao, Guang; Luo, Lian-cong; Zhu, Guang-wei; Liu, Ming-liang

    2008-06-01

    Spatial variation of chemical oxygen demand (COD) concentration was documented and significant correlations between COD concentration and chromophoric dissolved organic matter (CDOM) absorption, fluorescence, DOC concentration were found based on a cruise sampling in the northern region of Lake Taihu in summer including 42 samplings. The possible source of COD was also discussed using every two cruise samplings in summer and winter, respectively. The COD concentration ranged from 3.77 to 7.96 mg x L(-1) with a mean value of (5.90 +/- 1.54) mg x L(-1). The mean COD concentrations in Meiliang Bay and the central lake basin were (6.93 +/- 0.89) mg x L(-1) and (4.21 +/- 0.49) mg x L(-1) respectively. A significant spatial difference was found between Meiliang Bay and the central lake basin in COD concentration, CDOM absorption coefficient, fluorescence, DOC and phytoplankton pigment concentrations, decreasing from the river mouth to inner bay, outer bay and the central lake basin. Significant correlations between COD concentration and CDOM absorption, fluorescence, DOC concentration, suggested that COD concentration could be estimated and organic pollution could be assessed using CDOM absorption retrieved from remote sensing images. Significant and positive correlation was found between COD concentration and chlorophyll a concentration in summer. However, the correlation was weak or no correlation was found in winter. Furthermore, a significant higher COD concentration was found in summer than in winter (p summer, except for river terrestrial input.

  20. Biomarkers in natural fish populations indicate adverse biological effects of offshore oil production.

    Directory of Open Access Journals (Sweden)

    Lennart Balk

    Full Text Available Despite the growing awareness of the necessity of a sustainable development, the global economy continues to depend largely on the consumption of non-renewable energy resources. One such energy resource is fossil oil extracted from the seabed at offshore oil platforms. This type of oil production causes continuous environmental pollution from drilling waste, discharge of large amounts of produced water, and accidental spills.Samples from natural populations of haddock (Melanogrammus aeglefinus and Atlantic cod (Gadus morhua in two North Sea areas with extensive oil production were investigated. Exposure to and uptake of polycyclic aromatic hydrocarbons (PAHs were demonstrated, and biomarker analyses revealed adverse biological effects, including induction of biotransformation enzymes, oxidative stress, altered fatty acid composition, and genotoxicity. Genotoxicity was reflected by a hepatic DNA adduct pattern typical for exposure to a mixture of PAHs. Control material was collected from a North Sea area without oil production and from remote Icelandic waters. The difference between the two control areas indicates significant background pollution in the North Sea.It is most remarkable to obtain biomarker responses in natural fish populations in the open sea that are similar to the biomarker responses in fish from highly polluted areas close to a point source. Risk assessment of various threats to the marine fish populations in the North Sea, such as overfishing, global warming, and eutrophication, should also take into account the ecologically relevant impact of offshore oil production.

  1. 78 FR 27957 - Fisheries of the South Atlantic, Southeast Data, Assessment, and Review (SEDAR); Public Meetings

    Science.gov (United States)

    2013-05-13

    ..., describes the fisheries, evaluates the status of the stock, estimates biological benchmarks, projects future... to evaluate stock status, estimate population benchmarks and management criteria, and project future... South Atlantic stock of snowy [[Page 27958

  2. Hatchery tank enrichment affects cortisol levels and shelter-seeking in Atlantic salmon (Salmo salar)

    DEFF Research Database (Denmark)

    Näslund, Joacim; Rosengren, Malin; Del Villar, Diego

    2013-01-01

    Stocking programs using hatchery-reared salmon are often implemented for augmenting natural populations. However, survival of these fish is often low compared with wild conspecifics, possibly because of genetic, physiological, and behavioural deficiencies. Here, we compared presmolt Atlantic salm...

  3. Influence of phase separation on the anaerobic digestion of glucose: maximum COD turnover rate during continuous operation

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, A; Van Andel, J G; Breure, A M; Van Deursen, A

    1980-01-01

    A mineral medium containing 1% of glucose as the main carbon source was subjected to one-phase and two-phase anaerobic digestion processes under comparable conditions. The one-phase system combined acidogenic and methanogenic populations allowing a complete conversion of the carbon source into gaseous end products and biomass. The two-phase system consists of an acid reactor and a methane reactor connected in series allowing sequential acidogenesis and methanogenesis. Performance of the one-phase system is compared with that of the two-phase system. Maximum turnover of COD was determined for each system. Maximum specific sludge loading of the two-phase system was more than three times higher than that of the one-phase system. Effects of overloading each system were determined. The eco-physiological significance of phase separation is discussed briefly. (2 diagrams, 5 graphs, 41 references, 5 tables)

  4. Atlantic and indian oceans pollution in africa

    Science.gov (United States)

    Abubakar, Babagana

    Africa is the second largest and most populated continent after Asia. Geographically it is located between the Atlantic and Indian Oceans. Most of the Africa's most populated and industrialized cities are located along the coast of the continent facing the Atlantic and Indian Oceans, example of such cities include Casablanca, Dakar, Accra, Lagos, Luanda and Cape town all facing the Atlantic Ocean and cities like East London, Durban, Maputo, Dar-es-salaam and Mogadishu are all facing the Indian Ocean. As a result of the geographical locations of African Coastal Cities plus increase in their population, industries, sea port operations, petroleum exploration activities, trafficking of toxic wastes and improper waste management culture lead to the incessant increase in the pollution of the two oceans. NATURE OF POLLUTION OF THE ATLANTIC OCEAN i. The petroleum exploration activities going on along the coast of "Gulf of Guinea" region and Angola continuously causes oil spillages in the process of drilling, bunkering and discharging of petroleum products in the Atlantic Ocean. ii. The incessant degreasing of the Sea Ports "Quay Aprons" along the Coastal cities of Lagos, Luanda, Cape Town etc are continuously polluting the Atlantic Ocean with chemicals. iii. Local wastes generated from the houses located in the coastal cities are always finding their ways into the Atlantic Ocean. NATURE OF POLLUTION OF THE INDIAN OCEAN i. Unlike the Atlantic ocean where petroleum is the major pollutant, the Indian Ocean is polluted by Toxic / Radioactive waste suspected to have been coming from the developed nations as reported by the United Nations Environmental Programme after the Tsunami disaster in December 2004 especially along the coast of Somalia. ii. The degreasing of the Quay Aprons at Port Elizabeth, Maputo, Dar-es-Salaam and Mongolism Sea Ports are also another major source polluting the Indian Ocean. PROBLEMS GENERATED AS A RESULT OF THE OCEANS POLLUTION i. Recent report

  5. Spatio-temporal dynamics of cod nursery areas in the Baltic Sea

    Science.gov (United States)

    Hinrichsen, H.-H.; von Dewitz, B.; Lehmann, A.; Bergström, U.; Hüssy, K.

    2017-06-01

    In this study the drift of eastern Baltic cod larvae and juveniles spawned within the historical eastern Baltic cod spawning grounds was investigated by detailed drift model simulations for the years 1971-2010, to examine the spatio-temporal dynamics of environmental suitability in the nursery areas of juvenile cod settlement. The results of the long-term model scenario runs, where juvenile cod were treated as simulated passively drifting particles, enabled us to find strong indications for long-term variations of settlement and potentially the reproduction success of the historically important eastern Baltic cod nursery grounds. Only low proportions of juveniles hatched in the Arkona Basin and in the Gotland Basin were able to settle in their respective spawning ground. Ocean currents were either unfavorable for the juveniles to reach suitable habitats or transported the juveniles to nursery grounds of neighboring subdivisions. Juveniles which hatched in the Bornholm Basin were most widely dispersed and showed the highest settlement probability, while the second highest settlement probability and horizontal dispersal was observed for juveniles originating from the Gdansk Deep. In a long-term perspective, wind-driven transport of larvae/juveniles positively affected the settlement success predominately in the Bornholm Basin and in the Bay of Gdansk. The Bornholm Basin has the potential to contribute on average 54% and the Bay of Gdansk 11% to the production of juveniles in the Baltic Sea. Furthermore, transport of juveniles surviving to the age of settlement with origin in the Bornholm Basin contributed on average 13 and 11% to the total settlement in the Arkona Basin and in the Gdansk Deep, respectively. The time-series of the simulated occupied juvenile cod habitat in the Bornholm Basin and in the Gdansk Deep showed a similar declining trend as the Fulton's K condition factor of demersal 1-group cod, which may confirm the importance of oxygen-dependent habitat

  6. Potential of hydrolysis of particulate COD in extended anaerobic conditions to enhance biological phosphorous removal.

    Science.gov (United States)

    Jabari, P; Yuan, Q; Oleszkiewicz, J A

    2016-11-01

    The effect of anaerobic hydrolysis of particulate COD (pCOD) on biological phosphorous removal in extended anaerobic condition was investigated through (i) sequencing batch reactors (SBR)s with anaerobic hydraulic retention time (HRT) of 0.8, 2, and 4 h; (ii) batch tests using biomass from a full scale biological nutrient removal (BNR) plant; and (iii) activated sludge modeling (BioWin 4.1 simulation). The results from long-term SBRs operation showed that phosphorus removal was correlated to the ratio of filtered COD (FCOD) to total phosphorus (TP) in the influent. Under conditions with low FCOD/TP ratio (average of 20) in the influent, extending anaerobic HRT to 4 h in the presence of pCOD did not significantly improve overall phosphorous removal. During the period with high FCOD/TP ratio (average of 37) in the influent, all SBRs removed phosphorous completely, and the long anaerobic HRT did not have negative effect on overall phosphorous removal. The batch tests also showed that pCOD at different concentration during 4 h test did not affect the rate of anaerobic phosphorus release. The rate of anaerobic hydrolysis of pCOD was significantly low and extending the anaerobic HRT was ineffective. The simulation (BioWin 4.1) of SBRs with low influent FCOD/TP ratio showed that the default kinetics of anaerobic hydrolysis in ASM2d overestimated phosphorous removal in the SBRs (high anaerobic hydrolysis of pCOD). The default anaerobic hydrolysis rate in BioWin 4.1 (ten times lower) could produce similar phosphorous removal to that in the experiment. Results showed that the current kinetics of anaerobic hydrolysis in ASM2d could lead to considerable error in predicting phosphorus removal in processes with extended anaerobic HRT. Biotechnol. Bioeng. 2016;113: 2377-2385. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Unraveling biocomplexity of Northeast Atlantic herring stocks using SNP markers

    DEFF Research Database (Denmark)

    Bekkevold, Dorte; Limborg, Morten; Helyar, Sarah

    2012-01-01

    Atlantic herring (Clupea harengus) exhibit biocomplexity, with widespread, geographically explicit populations that perform long‐range migration to common feeding and wintering areas, where they are exploited by fisheries. This means that exploited stocks do not describe discrete units, thereby c...... and spatial dynamics applicable to stock assessment methods, as well as presenting a traceability tool for certification of herring and herring products...

  8. Growth changes in plaice, cod, haddock and saithe in the North Sea: a comparison of (post-)medieval and present-day growth rates based on otolith measurements

    Science.gov (United States)

    Bolle, Loes J.; Rijnsdorp, Adriaan D.; van Neer, Wim; Millner, Richard S.; van Leeuwen, Piet I.; Ervynck, Anton; Ayers, Richard; Ongenae, Ellen

    2004-05-01

    Fishing effort has strongly increased in the North Sea since the mid-19th century, causing a substantial reduction in the population size of exploited fish stocks. As fisheries research has developed simultaneously with the industrialisation of the fisheries, our knowledge of population dynamics at low levels of exploitations is limited. Otoliths retrieved from archaeological excavations offer a unique opportunity to study growth rates in the past. This study compares historical and present-day growth rates for four commercially important demersal fish species. A total of 2532 modern otoliths (AD 1984-1999) and 1286 historical otoliths (AD 1200-1925) obtained from archaeological excavations in Belgium and Scotland were analysed. Comparison of the growth patterns between eras revealed a major increase in growth rate of haddock, whereas growth changes were not observed in saithe and only in the smaller size classes of plaice and cod. Comparison of our results with literature data indicates that the observed growth rate changes in plaice and cod occurred within the 20th century. Apparently the onset of industrialised fisheries has not greatly affected the growth of plaice, cod and saithe populations in the North Sea. This result contradicts the expectation of density-dependent limitation of growth during the era of pre-industrialised fishing, but is in agreement with the concentration hypothesis of Beverton (Neth. J. Sea Res. 34 (1995) 1) stating that species which concentrate spatially into nursery grounds during their early life-history may 'saturate' the carrying capacity of the juvenile habitat even though the adult part of the population is not limited by the adult habitat.

  9. Comparative status and assessment of Limulus polyphemus with emphasis on the New England and Delaware Bay populations

    Science.gov (United States)

    Smith, David; Millard, Michael J.; Carmichael, Ruth H.

    2009-01-01

    Increases in harvest of the American horseshoe crab (Limulus polyphemus) during the 1990s, particularly for whelk bait, coupled with decreases in species that depend on their eggs has reduced horseshoe crab abundance, threatened their ecological relationships, and dictated precautionary management of the horseshoe crab resource. Accordingly, population assessments and monitoring programs have been developed throughout much of the horseshoe crab’s range. We review and discuss implications for several recent assessments of Delaware Bay and New England populations and a meta-analysis of region-specific trends. These assessments show that the western Atlantic distribution of the horseshoe crab is comprised of regional or estuarine-specific meta-populations, which exhibit distinct population dynamics and require management as separate units. Modeling of Delaware Bay and Cape Cod populations confirmed that overharvest caused declines, but indicated that some harvest levels are sustainable and consistent with population growth. Coast-wide harvest was reduced by 70% from 1998 to 2006, with the greatest reductions within Delaware Bay states. Harvest regulations in Delaware Bay starting in the late 1990s, such as harvest quotas, seasonal closures, male-only harvest, voluntary use of bait-saving devices, and establishment of the Carl N. Shuster Jr. Horseshoe Crab Reserve, were followed by stabilization and recent evidence of increase in abundance of horseshoe crabs in the region. However, decreased harvest of the Delaware Bay population has redirected harvest to outlying populations, particularly in New York and New England. While the recent Delaware Bay assessments indicate positive population growth, increased harvest elsewhere is believed to be unsustainable. Two important considerations for future assessments include (1) managing Delaware Bay horseshoe crab populations within a multi-species context, for example, to help support migratory shorebirds and (2

  10. CodY Promotes Sporulation and Enterotoxin Production by Clostridium perfringens Type A Strain SM101.

    Science.gov (United States)

    Li, Jihong; Freedman, John C; Evans, Daniel R; McClane, Bruce A

    2017-03-01

    Clostridium perfringens type D strains cause enterotoxemia and enteritis in livestock via epsilon toxin production. In type D strain CN3718, CodY was previously shown to increase the level of epsilon toxin production and repress sporulation. C. perfringens type A strains producing C. perfringens enterotoxin (CPE) cause human food poisoning and antibiotic-associated diarrhea. Sporulation is critical for C. perfringens type A food poisoning since spores contribute to transmission and resistance in the harsh food environment and sporulation is essential for CPE production. Therefore, the current study asked whether CodY also regulates sporulation and CPE production in SM101, a derivative of C. perfringens type A food-poisoning strain NCTC8798. An isogenic codY -null mutant of SM101 showed decreased levels of spore formation, along with lower levels of CPE production. A complemented strain recovered wild-type levels of both sporulation and CPE production. When this result was coupled with the earlier results obtained with CN3718, it became apparent that CodY regulation of sporulation varies among different C. perfringens strains. Results from quantitative reverse transcriptase PCR analysis clearly demonstrated that, during sporulation, codY transcript levels remained high in SM101 but rapidly declined in CN3718. In addition, abrB gene expression patterns varied significantly between codY -null mutants of SM101 and CN3718. Compared to the levels in their wild-type parents, the level of abrB gene expression decreased in the CN3718 codY -null mutant strain but significantly increased in the SM101 codY -null mutant strain, demonstrating CodY-dependent regulation differences in abrB expression between these two strains. This difference appears to be important since overexpression of the abrB gene in SM101 reduced the levels of sporulation and enterotoxin production, supporting the involvement of AbrB repression in regulating C. perfringens sporulation. Copyright © 2017

  11. The effect of pH and operation mode for COD removal of slaughterhouse wastewater with Anaerobic Batch Reactor (ABR

    Directory of Open Access Journals (Sweden)

    Maria Octoviane Dyan

    2015-01-01

    Full Text Available Disposal of industrial wastes in large quantities was not in accordance with today's standards of waste into environmental issues that must be overcome with proper treatment. Similarly, the abattoir wastewater that contains too high organic compounds and suspended solids. The amount of liquid waste disposal Slaughterhouse (SW with high volume also causes pollution. The research aim to resolve this problem by lowering the levels of BOD-COD to comply with effluent quality standard. Anaerobic process is the right process for slaughterhouse wastewater treatment because of high content of organic compounds that can be utilized by anaerobic bacteria as a growth medium. Some research has been conducted among abattoir wastewater treatment using anaerobic reactors such as ABR, UASB and ASBR. Our research focuses on the search for the optimum results decline effluent COD levels to match the quality standards limbah and cow rumen fluid with biodigester ABR (Anaerobic Batch Reactor. The variables used were PH of 6, 7, and 8, as well as the concentration ratio of COD: N is 400:7; 450:7, and 500:7. COD value is set by the addition of N derived from urea [CO(NH2 2]. COD levels will be measured daily by water displacement technique. The research’s result for 20 days seen that optimum PH for biogas production was PH 7,719 ml. The optimum PH for COD removal is PH 6, 72.39 %. The operation mode COD:N for biogas production and COD removal is 500:7, with the production value is 601 ml and COD removal value is 63.85 %. The research’s conclusion, the PH optimum for biogas production was PH 7, then the optimum PH for COD removal is PH 6. The optimum operation mode COD:N for biogas production and COD removal was 500:7

  12. Relationships between water quality parameters in rivers and lakes: BOD5, COD, NBOPs, and TOC.

    Science.gov (United States)

    Lee, Jaewoong; Lee, Seunghyun; Yu, Soonju; Rhew, Doughee

    2016-04-01

    Biological oxygen demand (BOD5) or chemical oxygen demand (COD) analysis is widely used to evaluate organic pollutants in water systems as well as the efficiency of wastewater treatment plants. However, both analysis methods have restrictions such as being insensitive, imprecise, time-consuming, and the production of chemical waste. Therefore, total organic carbon (TOC) analysis for organic pollutants has been considered for an alternative analysis instead of BOD5 or COD. Several studies have investigated the replacement of BOD5 or COD with TOC in wastewater samples; however, few studies have investigated the relationships between water quality parameters in rivers and lakes. Therefore, this study evaluated the relationships between BOD5, COD, or NBOPs and TOC by the analysis of national water quality monitoring data of rivers and lakes for 5 years. High correlation coefficients (r) of 0.87 and 0.66 between BOD5 and TOC (p TOC (p TOC was 0.93 for rivers and 0.72 for lakes. The coefficients of determination (R 2) were 0.75 and 0.44 between BOD5 and TOC for rivers and lakes as well as were 0.87 and 0.57 between COD and TOC for rivers and lakes, respectively. The coefficient of determination (R 2) between NBOPs and TOC was 0.73 for rivers and 0.52 for lakes.

  13. COD fractions of leachate from aerobic and anaerobic pilot scale landfill reactors

    International Nuclear Information System (INIS)

    Bilgili, M. Sinan; Demir, Ahmet; Akkaya, Ebru; Ozkaya, Bestamin

    2008-01-01

    One of the most important problems with designing and maintaining a landfill is managing leachate that generated when water passes through the waste. In this study, leachate samples taken from aerobic and anaerobic landfill reactors operated with and without leachate recirculation are investigated in terms of biodegradable and non-biodegradable fractions of COD. The operation time is 600 days for anaerobic reactors and 250 days for aerobic reactors. Results of this study show that while the values of soluble inert COD to total COD in the leachate of aerobic landfill with leachate recirculation and aerobic dry reactors are determined around 40%, this rate was found around 30% in the leachate of anaerobic landfill with leachate recirculation and traditional landfill reactors. The reason for this difference is that the aerobic reactors generated much more microbial products. Because of this condition, it can be concluded that total inert COD/total COD ratios of the aerobic reactors were 60%, whereas those of anaerobic reactors were 50%. This study is important for modeling, design, and operation of landfill leachate treatment systems and determination of discharge limits

  14. Stable isotope evidence for late medieval (14th-15th C origins of the eastern Baltic cod (Gadus morhua fishery.

    Directory of Open Access Journals (Sweden)

    David C Orton

    Full Text Available Although recent historical ecology studies have extended quantitative knowledge of eastern Baltic cod (Gadus morhua exploitation back as far as the 16th century, the historical origin of the modern fishery remains obscure. Widespread archaeological evidence for cod consumption around the eastern Baltic littoral emerges around the 13th century, three centuries before systematic documentation, but it is not clear whether this represents (1 development of a substantial eastern Baltic cod fishery, or (2 large-scale importation of preserved cod from elsewhere. To distinguish between these hypotheses we use stable carbon and nitrogen isotope analysis to determine likely catch regions of 74 cod vertebrae and cleithra from 19 Baltic archaeological sites dated from the 8th to the 16th centuries. δ(13C and δ(15N signatures for six possible catch regions were established using a larger sample of archaeological cod cranial bones (n = 249. The data strongly support the second hypothesis, revealing widespread importation of cod during the 13th to 14th centuries, most of it probably from Arctic Norway. By the 15th century, however, eastern Baltic cod dominate within our sample, indicating the development of a substantial late medieval fishery. Potential human impact on cod stocks in the eastern Baltic must thus be taken into account for at least the last 600 years.

  15. Rethinking Atlantic History

    Directory of Open Access Journals (Sweden)

    James Walvin

    2009-12-01

    Full Text Available [First paragraph] Shaping the Stuart World 1603-1714: The Atlantic Connection. Allan I. Macinnes & Arthur H. Williamson (eds.. Leiden: Brill Academic Publishers, 2006. xiv + 389 pp. (Cloth US$ 135.00 Slavery and the British Empire: From Africa to America. Kenneth Morgan. New York: Oxford University Press, 2007. x + 221 pp. (Paper US$ 32.00 Although an important debate continues about the concept itself, the use of “the Atlantic” has embedded itself in scholarly vernacular. The scholarly output directly spawned by an engagement with the concept continues apace. That ocean, and the peoples who lived and traded along its edges, and who finally moved across it, have provided an important geographical focus for some major reconsiderations of modern history. Prompted by the Macinnes/Williamson volume, I returned to my own undergraduate and graduate notes and essays from courses on Stuart Britain: the Atlantic was totally absent – not even present as a distant speck on our intellectual map. We studied, and debated, the formal histories of migrations to the Americas (i.e. European migrations but there was no mention of Africa or Africans. And no sense was conveyed that the European engagement with the Americas (in their totality – as opposed to North America was a two-way, mutual force: that the European world was influenced, indeed shaped in many critical regards, by the Americas: by the land, the products, the peoples, and by the markets of that hemisphere. At its most obvious in the ebb and flow of peoples, even that eluded the historians I encountered as a student. It was as if we were talking about a different cosmos; few moved beyond the conventions of European migrations westwards and little attention was paid to that most dominant of migrations – the enforced African migrations to the Americas.

  16. Correlation of COD and BOD of domestic wastewater with the power output of bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Khan, A M; Ataullah,; Shaheen, A; Ahmad, I; Malik, F; Shahid, H A [Federal Urdu University of Arts, Science and Technology, Gulshan-e-Iqbal Campus, University Road, Karachi-75300 (Pakistan). Research Laboratory of Bioenergy, Department of Chemistry

    2011-04-15

    This research article deals with the studies on the development of the correlation of COD, BOD, and BOD/sub 5/ of domestic wastewater (DWW), and fermented domestic wastewater (FDWW) with the power output of the microbial fuel cell (MFC). The fermentation of DWW was carried out with yeast (Saccharomyces cerevisiae), and yogurt bacteria (Streptococcus lactis) to produce biohydrogen which was converted to the electrical energy through the development of microbial fuel cell (MFC). The values of COD, BOD, and BOD/sub 5/ for yogurt fermented domestic wastewater (Yogurt-FDWW) were found to be greater than the values of yeast fermented domestic wastewater (Yeast-FDWW). The power output of DWW and FDWW was increased with the increase in COD, BOD and BOD/sub 5/ values. The main objective of this article is to develop the renewable alternative of fossil fuels which are the major cause of global warming and global pollution. (author)

  17. Correlation of COD and BOD of domestic wastewater with the power output of bioreactor

    International Nuclear Information System (INIS)

    Khan, A.M.; Ataullah; Shaheen, A.; Ahmad, I.; Malik, F.; Shahid, H.A.

    2011-01-01

    This research article deals with the studies on the development of the correlation of COD, BOD, and BOD/sub 5/ of domestic wastewater (DWW), and fermented domestic wastewater (FDWW) with the power output of the microbial fuel cell (MFC). The fermentation of DWW was carried out with yeast (Saccharomyces cerevisiae), and yogurt bacteria (Streptococcus lactis) to produce biohydrogen which was converted to the electrical energy through the development of microbial fuel cell (MFC). The values of COD, BOD, and BOD/sub 5/ for yogurt fermented domestic wastewater (Yogurt-FDWW) were found to be greater than the values of yeast fermented domestic wastewater (Yeast-FDWW). The power output of DWW and FDWW was increased with the increase in COD, BOD and BOD/sub 5/ values. The main objective of this article is to develop the renewable alternative of fossil fuels which are the major cause of global warming and global pollution. (author)

  18. Removal of COD and color loads in bleached kraft pulp effluents by bottom ashes from boilers.

    Science.gov (United States)

    Van Tran, A

    2008-07-01

    The effectiveness of the bottom ashes from biomass and coal-fired boilers in removing chemical oxygen demand (COD) and colorloads in effluents of a kraft pulp bleachery plant is investigated. The effluents tested are those of the sulfuric acid treatment (A stage) of a hardwood kraft pulp, and of the first acidic (chlorine or chlorine dioxide) and second alkaline (extraction) stages in the chlorine and elemental chlorine-free (ECF) bleaching lines of hardwood and softwood kraft pulps. The coal-fired boiler's bottom ashes are unable to remove either COD or color load in the bleached kraft pulp effluents. However, the bottom ashes of the biomass boiler are effective in removing COD and color loads of the acidic and alkaline effluents irrespective of the bleaching process or wood species. In particular, these ashes increase the pH of all the effluents examined.

  19. Escape windows to improve the size selectivity in the Baltic cod trawl fishery

    DEFF Research Database (Denmark)

    Madsen, Niels; Holst, René; Foldager, L.

    2002-01-01

    A rapid decrease of the stock of Baltic cod (Gadus morhua) has provided the incentive to improve the size selectivity in the trawl fishery. Use of escape windows is permitted in the legislation to give means of improving the size selectivity of cod as an alternative to a traditional standard codend....... The history of the use of escape windows in the Baltic Sea cod fishery is reviewed. The present escape windows do not function optimally. The objective of this new experiment was to compare an improved design of escape window, which is placed in the upper panel, with that of standard codend. Three standard...... of the codend selectivity was formulated to analyse the results and determine the effects of codend type, mesh size and other recorded variables. L50 and SR increased significantly with the mesh size. L50 was significantly increased and SR significantly reduced for a window codend with the same window mesh size...

  20. Evaluation of chemical markers for age validation of western Baltic cod (Gadus morhua otoliths

    Directory of Open Access Journals (Sweden)

    Sven Stötera

    2015-11-01

    Baltic cod were intraperitoneally injected with the different chemicals and kept for 47 days in netpens. The lowest mortality and best ring formation was observed at 100mg/kg cod wet weight compared to 50 and 25mg/kg wet weight (TET only. Preliminary analysis suggests that the simultaneous injection of TET and STR decreases the visibility of TET-rings. This is probably due to a binding interaction between both markers in the body of the fish, so that less TET is bound in the otolith. The use of tetracycline hydrochloride in the concentrations of 50 mg/kg and 100 mg/kg fish were considered the most appropriate to mark Baltic cod for age validation in large-scale mark-recapture experiments. TET and STR should not be injected together.

  1. Removal of COD and turbidity to improve wastewater quality using electrocoagulation technique

    International Nuclear Information System (INIS)

    Mohd Faiqun Niam; Fadil Othman; Johan Sohaili; Zulfa Fauzia

    2007-01-01

    Electrocoagulation (EC) is becoming a popular process to be used for wastewater treatment. The removal of COD and turbidity from wastewater by EC using iron (Fe) electrode material was investigated in this paper. Several working parameters, such as pH, current density, and operating time were studied in an attempt to achieve a higher removal capacity. Wastewater sample was made from milk powder with initial COD of 1140 mgL -1 and turbidity of 491 NTU. Current density was varied from 3.51 to 5.62 mA cm -2 , and operating time of between 30 and 50 minutes. The results show that the effluent wastewater was very clear and its quality exceeded the direct discharge standard. The removal efficiencies of COD and turbidity were high, being more than 65 % and 95 %. In addition, the experimental results also show that the electrocoagulation can neutralize pH of wastewater. (author)

  2. Optimizing removal of cod from water by catalytic ozonation of cephalexin using response surface methodology

    International Nuclear Information System (INIS)

    Akhtar, J.; Amin, N.S.; Zahoor, M.K.

    2013-01-01

    Response surface methodology (RSM) has been used to optimize the effect of circulation rates, ozone supply, cephalexin (CEX) concentration, and granular activated carbon (GAC) dose on removal of COD from solution. According to statistical analysis, all of the input variables exerted significant influence on COD removal, however, the effect of interaction variables was not found to be significant on comparative basis. Further, the developed quadratic regression model based on obtained results emphasized the significance of individual terms and little of interaction terms. The values of r/sup 2/ (0.959), adjusted r/sup 2/ (0.902) obtained by analysis of variance (ANOVA) indicates the significance of quadratic model in predicting desired response. The maximum of 70% of COD was removed in these experiments and optimized value according to main effect of variables was 60%. (author)

  3. Association between nematode Hysterothylacium aduncum invasion of cod larvae and growth

    DEFF Research Database (Denmark)

    Mehrdana, Foojan; Bahlool, Qusay Z. M.; Kuhn, Jesper

    Parasitic nematodes of the superfamily Ascaridoidea are distributed worldwide also with numerous representatives in fish. They have an important role to play in the aquatic environment and may affect survivability of fish. The life cycle of many of these fish infecting roundworm species includes...... invertebrates and fish species and for some species also higher vertebrate hosts. We have recently demonstrated that fry of North Sea cod has a high prevalence of infection with regard to the nematode Hysterothylacium aduncum and it was indicated that these infections could affect survival of cod and thereby......, lapillus otoliths were removed, polished and the number of growth zones in each otolith counted by light microscopy. Each growth zone indicates one day of the fish life span. Covariance analysis demonstrated highly significant differences (p≤ 0.001) between the growth rate of infected and uninfected cod...

  4. Virginia Atlantic Coast Recreational Use

    Data.gov (United States)

    Virginia Department of Environmental Quality — As a member of the Mid-Atlantic Regional Council on the Ocean (MARCO), Virginia, through its Coastal Zone Management (CZM) Program, collected information on how the...

  5. VA Atlantic Coast Recreational Use

    Data.gov (United States)

    Virginia Department of Environmental Quality — As a member of the Mid-Atlantic Regional Council on the Ocean (MARCO), Virginia, through its Coastal Zone Management (CZM) Program, collected information on how the...

  6. Spatio-temporal variability of the North Sea cod recruitment in relation to temperature and zooplankton.

    Directory of Open Access Journals (Sweden)

    Delphine Nicolas

    Full Text Available The North Sea cod (Gadus morhua, L. stock has continuously declined over the past four decades linked with overfishing and climate change. Changes in stock structure due to overfishing have made the stock largely dependent on its recruitment success, which greatly relies on environmental conditions. Here we focus on the spatio-temporal variability of cod recruitment in an effort to detect changes during the critical early life stages. Using International Bottom Trawl Survey (IBTS data from 1974 to 2011, a major spatio-temporal change in the distribution of cod recruits was identified in the late 1990s, characterized by a pronounced decrease in the central and southeastern North Sea stock. Other minor spatial changes were also recorded in the mid-1980s and early 1990s. We tested whether the observed changes in recruits distribution could be related with direct (i.e. temperature and/or indirect (i.e. changes in the quantity and quality of zooplankton prey effects of climate variability. The analyses were based on spatially-resolved time series, i.e. sea surface temperature (SST from the Hadley Center and zooplankton records from the Continuous Plankton Recorder Survey. We showed that spring SST increase was the main driver for the most recent decrease in cod recruitment. The late 1990s were also characterized by relatively low total zooplankton biomass, particularly of energy-rich zooplankton such as the copepod Calanus finmarchicus, which have further contributed to the decline of North Sea cod recruitment. Long-term spatially-resolved observations were used to produce regional distribution models that could further be used to predict the abundance of North Sea cod recruits based on temperature and zooplankton food availability.

  7. PEMANFAATAN SPUIT BEKAS SEBAGAI MEDIA BIOFILTRASI DALAM MENURUNKAN KADAR BOD DAN COD AIR LIMBAH LAUNDRY

    Directory of Open Access Journals (Sweden)

    Susilawati Susilawati

    2016-07-01

    Full Text Available Abstract: Utilization Spuit Used As Media biofilters on Reducing levels of BOD and COD Wastewater Laundry. The aim of this study was to test the ability of the media syringe biofiltration method used in lowering levels of BOD and COD in waste water laundry Hospital Dr. Soedarso Pontianak. This research is a quasi-experimental research design with one group pretest-posttest. Laboratory results mean BOD levels before processing is 103.63 mg/L and the average after processing into 46.41 mg/ L, with a value of 55.21 % effectiveness. While the average COD level before processing is 413.70 mg / L and the average after processing into a 195.88 mg/L with a value of 45.92% effectiveness. Expected to other researchers to control the pH and blowers before treatment and during treatment, as it will affect the final result. Abstrak : Pemanfaatan Spuit Bekas Sebagai Media Biofiltrasi Dalam Menurunkan Kadar BOD dan COD Air Limbah Laundry. Tujuan dari penelitian ini untuk menguji kemampuan metode biofiltrasi dengan media spuit bekas pakai dalam menurunkan kadar BOD dan COD pada air limbah laundry RSUD Dr. Soedarso Pontianak. Penelitian ini merupakan penelitian eksperimen semu dengan rancangan penelitian one group pre test post test. Hasil laboratorium rata-rata kadar BOD sebelum pengolahan yaitu 103.63 mg/L dan rata-rata setelah pengolahan menjadi 46.41 mg/L, dengan nilai efektivitas 55,21 %. Sedangkan rata-rata kadar COD sebelum pengolahan yaitu 413.70 mg/L dan rata-rata setelah pengolahan menjadi 195.88 mg/L dengan nilai efektivitas 45,92 %. Diharapkan kepada peneliti lain untuk mengontrol pH dan blower sebelum perlakuan dan pada saat perlakuan, jika melakukan penelitian sejenis karena akan mempengaruhi hasil akhir.

  8. Degradation of ATP and glycogen in cod ( Gadus morhua ) muscle during freezing

    DEFF Research Database (Denmark)

    Cappeln, Gertrud; Jessen, Flemming

    2001-01-01

    Changes in ATP, IMP, lactate and glycogen contents in the muscle of cod were followed during freezing at temperatures of -20C and -45C. ATP degradation was accompanied by a corresponding increase in IMP content. Simultaneous measurement of temperature showed that at both freezing rates......, the greatest decrease in ATP content was observed when the temperature reached -0.8C. Glycolysis occurred during freezing of cod as indicated by an increase in lactate content. The changes found in all measured metabolites were more pronounced when freezing was performed at a slow rate compared to a fast rate...

  9. Otolith microstructure analysis to resolve seasonal patterns of hatching and settlement in western Baltic cod

    DEFF Research Database (Denmark)

    Rehberg-Haas, Sabine; Hammer, Cornelius; Hillgruber, Nicola

    2012-01-01

    Previous studies showed that Baltic cod (Gadus morhua) settle to demersal life at a given size, while the annulus is formed seasonally, irrespective of size. The goal of this study was to examine the timing of check formation in juvenile Baltic cod otoliths to validate macrostructural ageing...... and to differentiate between true annuli and secondary structures such as settlement checks. Otoliths were collected from fish off Fehmarn Island in 2008 and 2009, and were examined for macrostructural and microstructural patterns using light and scanning electron microscopy. All fish examined were age-0. Back...

  10. Modelling and simulation of size selectivity in diamond mesh trawl cod-ends

    DEFF Research Database (Denmark)

    Herrmann, Bent

    of the fishing gear. The cod-end is the rearmost part of a trawl where catch accumulates and in which most of the size selection is known to take place. To date, the main method used to assess the selectivity of trawl cod-ends has been to run sea trials followed by statistical analysis of the obtained......Within many fisheries there is a widespread discard of fish. Furthermore, there are several fisheries where fish are caught before reaching the optimal size, leading to an adverse exploitation of the resources. One way to achieve a more optimal exploitation is to improve the size selectivity...

  11. Improvement of COD and color removal from UASB treated poultry manure wastewater using Fenton's oxidation

    International Nuclear Information System (INIS)

    Yetilmezsoy, Kaan; Sakar, Suleyman

    2008-01-01

    The applicability of Fenton's oxidation as an advanced treatment for chemical oxygen demand (COD) and color removal from anaerobically treated poultry manure wastewater was investigated. The raw poultry manure wastewater, having a pH of 7.30 (±0.2) and a total COD of 12,100 (±910) mg/L was first treated in a 15.7 L of pilot-scale up-flow anaerobic sludge blanket (UASB) reactor. The UASB reactor was operated for 72 days at mesophilic conditions (32 ± 2 deg. C) in a temperature-controlled environment with three different hydraulic retention times (HRT) of 15.7, 12 and 8.0 days, and with organic loading rates (OLR) between 0.650 and 1.783 kg COD/(m 3 day). Under 8.0 days of HRT, the UASB process showed a remarkable performance on total COD removal with a treatment efficiency of 90.7% at the day of 63. The anaerobically treated poultry manure wastewater was further treated by Fenton's oxidation process using Fe 2+ and H 2 O 2 solutions. Batch tests were conducted on the UASB effluent samples to determine the optimum operating conditions including initial pH, effects of H 2 O 2 and Fe 2+ dosages, and the ratio of H 2 O 2 /Fe 2+ . Preliminary tests conducted with the dosages of 100 mg Fe 2+ /L and 200 mg H 2 O 2 /L showed that optimal initial pH was 3.0 for both COD and color removal from the UASB effluent. On the basis of preliminary test results, effects of increasing dosages of Fe 2+ and H 2 O 2 were investigated. Under the condition of 400 mg Fe 2+ /L and 200 mg H 2 O 2 /L, removal efficiencies of residual COD and color were 88.7% and 80.9%, respectively. Under the subsequent condition of 100 mg Fe 2+ /L and 1200 mg H 2 O 2 /L, 95% of residual COD and 95.7% of residual color were removed from the UASB effluent. Results of this experimental study obviously indicated that nearly 99.3% of COD of raw poultry manure wastewater could be effectively removed by a UASB process followed by Fenton's oxidation technology used as a post-treatment unit

  12. Improvement of COD and color removal from UASB treated poultry manure wastewater using Fenton's oxidation.

    Science.gov (United States)

    Yetilmezsoy, Kaan; Sakar, Suleyman

    2008-03-01

    The applicability of Fenton's oxidation as an advanced treatment for chemical oxygen demand (COD) and color removal from anaerobically treated poultry manure wastewater was investigated. The raw poultry manure wastewater, having a pH of 7.30 (+/-0.2) and a total COD of 12,100 (+/-910) mg/L was first treated in a 15.7 L of pilot-scale up-flow anaerobic sludge blanket (UASB) reactor. The UASB reactor was operated for 72 days at mesophilic conditions (32+/-2 degrees C) in a temperature-controlled environment with three different hydraulic retention times (HRT) of 15.7, 12 and 8.0 days, and with organic loading rates (OLR) between 0.650 and 1.783 kg COD/(m3day). Under 8.0 days of HRT, the UASB process showed a remarkable performance on total COD removal with a treatment efficiency of 90.7% at the day of 63. The anaerobically treated poultry manure wastewater was further treated by Fenton's oxidation process using Fe2+ and H2O2 solutions. Batch tests were conducted on the UASB effluent samples to determine the optimum operating conditions including initial pH, effects of H2O2 and Fe2+ dosages, and the ratio of H2O2/Fe2+. Preliminary tests conducted with the dosages of 100 mg Fe2+/L and 200 mg H2O2/L showed that optimal initial pH was 3.0 for both COD and color removal from the UASB effluent. On the basis of preliminary test results, effects of increasing dosages of Fe2+ and H2O2 were investigated. Under the condition of 400 mg Fe2+/L and 200 mg H2O2/L, removal efficiencies of residual COD and color were 88.7% and 80.9%, respectively. Under the subsequent condition of 100 mg Fe2+/L and 1200 mg H2O2/L, 95% of residual COD and 95.7% of residual color were removed from the UASB effluent. Results of this experimental study obviously indicated that nearly 99.3% of COD of raw poultry manure wastewater could be effectively removed by a UASB process followed by Fenton's oxidation technology used as a post-treatment unit.

  13. Linking lipid dynamics with the reproductive cycle in Baltic cod Gadus morhua

    DEFF Research Database (Denmark)

    Røjbek, Maria; Jacobsen, Charlotte; Tomkiewicz, Jonna

    2012-01-01

    ovaries and decreased in late maturing and spawning fish, most likely due to their antioxidant protection activity. The fatty acid composition of cod liver reflected its clupeid prey. The ratio of 18:1n-9 to DHA was almost twice as high in sprat as in herring and indicated the ratio of sprat and herring...... with cod ovarian development in the central Baltic Sea, and may be associated with the delay in spawning and affect egg and larval survival; however, this needs further verification in experimental studies....

  14. Fishing gear-induced skin ulcerations in Baltic cod, Gadus morhua L

    DEFF Research Database (Denmark)

    Mellergaard, Stig; Bagge, O.

    1998-01-01

    In 1982 a high prevalence of skin ulcerations was observed in Baltic cod in the vicinity of the Danish island of Bornholm. In March the prevalence varied from G to 13%, and in May it had increased to between 26 and 48%. The ulcerations had a sequential development. The initial stage appeared...... from the nets, combined with bilateral occurrence of the ulcers, strongly indicates that the skin ulcers were induced by the fishing gear. Features of the pathology could be linked to the temporary retention of cod in trawl meshes....

  15. Eastern Baltic cod in distress: biological changes and challenges for stock assessment

    DEFF Research Database (Denmark)

    Eero, Margit; Hjelm, Joakim; Behrens, Jane

    2015-01-01

    The eastern Baltic (EB) cod (Gadus morhua) stock was depleted and overexploited for decades until the mid-2000s, when fishing mortality rapidly declined and biomass started to increase, as shown by stock assessments. These positive developments were partly assigned to effective management measures...... that the stock is in distress. In this study, we (i) summarize the knowledge of recent changes in cod biology and ecosystem conditions, (ii) describe the subsequent challenges for stock assessment, and (iii) highlight the key questions where answers are urgently needed to understand the present stock status...

  16. Effects of mixtures of persistent organic pollutants (POPs) derived from cod liver oil on H295R steroidogenesis

    NARCIS (Netherlands)

    Montano, M.; Zimmer, K.E.; Dahl, E.; Berge, V.; Olsaker, I.; Skaare, J.U.; Murk, A.J.; Ropstad, E.; Verhaegen, S.

    2011-01-01

    Crude cod liver oil and liver oil supplements are consumed as a source of vitamin A, D and polyunsaturated fatty acids; during winter and early pregnancy. Crude cod liver oil however constitutes a considerable source of persistent organic pollutants (POPs). This paper aimed at characterizing and

  17. Lipid biomarkers : Linking the utilization of frontal plankton biomass to enhanced condition of juvenile North Sea cod

    DEFF Research Database (Denmark)

    St. John, Michael; Lund, T.

    1996-01-01

    , hatched and the N1 nauplii from these different feeding regimes fed to post yolk-sac larval North Sea cod. Post yolk-sac larval cod required 8 d on either a Heterocapsa- or Skeletonema-based food chain before tracer Lipid signals (the ratio of the lipids 16:1 omega 7 to 16:0) in the larvae began to change...

  18. 75 FR 52478 - Fisheries of the Exclusive Economic Zone Off Alaska; Reallocation of Pacific Cod in the Bering...

    Science.gov (United States)

    2010-08-26

    ... a timely fashion and would delay the reallocation of Pacific cod specified from trawl catcher... catcher vessel Pacific cod fishery is currently open, it is important to immediately inform the industry... and efficient operation of this fishery, to allow the industry to plan for the fishing season, and to...

  19. Freshness assessment of thawed and chilled cod fillets packed in modified atmosphere using near-infrared spectroscopy

    DEFF Research Database (Denmark)

    Bøknæs, Niels; Jensen, K.N.; Andersen, Charlotte Møller

    2002-01-01

    Near-infrared reflectance (NIR) spectra was recorded of 105 samples of cod mince prepared from chill stored thawed cod fillets of varying quality in modified atmosphere packaging (MAP). Traditional chemical, physical, microbiological and sensory quality methods developed for assessing fresh fish...

  20. The Evaluation of Removal Efficiency of COD Due to Water Contaminated by Gasoline by Granular Active Carbon

    Directory of Open Access Journals (Sweden)

    MH Salmani

    2014-11-01

    Conclusion: We can conclude from this study that the activated carbon is an appropriate adsorbent for decreasing of COD due to gasoline contamination in water. The use of this adsorbent can well decrease COD of water contamination due to gasoline at times of 30 min.

  1. 76 FR 73513 - Fisheries of the Exclusive Economic Zone Off Alaska; Revisions to Pacific Cod Fishing in the...

    Science.gov (United States)

    2011-11-29

    ... term of the permit. Third, it requires an operator of any Federally permitted pot or hook-and-line C/P... catching a greater amount of Pacific cod in the parallel fishery than has been allocated to their sector from the BSAI total allowable catch. Maintaining Pacific cod catch amounts within BSAI sector...

  2. 77 FR 8177 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the...

    Science.gov (United States)

    2012-02-14

    ... Using Pot Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National Marine Fisheries...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels using pot gear in the... season allowance of the 2012 Pacific cod total allowable catch apportioned to vessels using pot gear in...

  3. 77 FR 14305 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Using Jig Gear in the...

    Science.gov (United States)

    2012-03-09

    ... Using Jig Gear in the Central Regulatory Area of the Gulf of Alaska AGENCY: National Marine Fisheries...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels using jig gear in the... season allowance of the 2012 Pacific cod total allowable catch apportioned to vessels using jig gear in...

  4. 77 FR 6683 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod by Vessels Using Pot Gear in the...

    Science.gov (United States)

    2012-02-09

    ... Using Pot Gear in the Western Regulatory Area of the Gulf of Alaska AGENCY: National Marine Fisheries...; closure. SUMMARY: NMFS is prohibiting directed fishing for Pacific cod by vessels using pot gear in the... season allowance of the 2012 Pacific cod total allowable catch apportioned to vessels using pot gear in...

  5. 76 FR 44699 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod Allocations in the Gulf of...

    Science.gov (United States)

    2011-07-26

    ... Atmospheric Administration 50 CFR Parts 679 and 680 Fisheries of the Exclusive Economic Zone Off Alaska... 0648-AY53 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod Allocations in the Gulf of... competition among sectors and support stability in the Pacific cod fishery. This rule would also limit access...

  6. 76 FR 37763 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod Allocations in the Gulf of...

    Science.gov (United States)

    2011-06-28

    ...-AY53 Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Cod Allocations in the Gulf of Alaska... the uncertainty regarding the distribution of Pacific cod catch, enhance stability among the sectors... available for public review and comment. The groundfish fisheries in the exclusive economic zone of the Gulf...

  7. Thawed cod fillets spoil less rapidly than unfrozen fillets when stored under modified atmosphere at 2 degrees C.

    Science.gov (United States)

    Guldager, H S; Bøknaes, N; Osterberg, C; Nielsen, J; Dalgaard, P

    1998-09-01

    The effect of two months of frozen storage at -20 degrees C on the spoilage characteristics and shelf life of thawed and modified atmosphere packed (MAP) cod fillets stored at 2 degrees C was studied. Thawed MAP cod fillets were compared with fresh cod fillets stored in CO2-containing modified atmospheres with and without added oxygen. The shelf life of 11 to 12 days in the fresh MAP cod was extended to more than 20 days in the thawed MAP cod at 2 degrees C. This shelf life extension was most likely due to the inactivation of the spoilage bacterium Photobacterium phosphoreum during frozen storage as reflected both in chemical analyses and sensory evaluation. In contrast to fresh MAP cod fillets no significant production of trimethylamine occurred and almost no amine odor and taste were detected during 20 days of chill storage of thawed MAP cod fillets. The use of frozen fillets as raw material not only provides a more stable product in MAP but also allows much greater flexibility for production and distribution. However, a slightly increased concentration of dimethylamine, a larger drip loss, and detection of weak frozen storage flavor were observed in the thawed MAP cod fillets.

  8. Co-distribution of seabirds and their polar cod prey near the ice edge in southern Baffin Bay

    DEFF Research Database (Denmark)

    LeBlanc, Mathieu; Gauthier, S; Mosbech, Anders

    species, and age-1 polar cod found in bird stomachs were likely individuals associated to ice. At a large scale of hundreds of kilometers, seabirds and age-0 polar cod were more abundant in ice-covered habitats (30 to 100% ice concentration). At medium and small scale of 12.5 and 1 km respectively...

  9. Theoretical study of the influence of twine thickness on haddock selectivity in diamond mesh cod-ends

    DEFF Research Database (Denmark)

    Herrmann, Bent; O'Neill, F.G.

    2006-01-01

    Using the cod-end simulation model PRESEMO, the influence of twine thickness on cod-end selectivity is investigated. The reduction of lateral mesh opening that arises as a result of both twine bending stiffness and the physical presence of the twine is considered. While it is shown that this lead...

  10. North Atlantic Energy Structures

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, S. [North Atlantic Energy Structures Inc., St. John' s, NL (Canada); Derradji, A. [National Research Council of Canada, St. John' s, NL (Canada). Inst. for Ocean Technology

    2005-07-01

    North Atlantic Energy Structures Inc. is in the process of designing a tidal fence for a site near the Straits of Belle Isle. This presentation provided details of both the design and the location in which the wave energy plant will be installed. Design constraints included a short seasonal work window, and a harsh but pristine environment. Design specifications of the paddlewheels and caissons were presented. The paddlewheel is iceberg and slab ice resistant, and has portals below the wheel axis, a water-free upper chamber, and bi-directional power generation. The planned installation sequence was presented, as well as details of a hydrodynamic simulation examining torque on the turbines in the tidal energy chamber. Results of the study indicated that 20 paddlewheels per caisson provided the equivalent of 12 MW of energy. A tidal fence of 70 to 80 caissons provided the equivalent of 1.2 GW of energy. A slab ice simulation study was outlined, and details of the pumping station, inlet and hydro-generation station were provided. A map of the proposed siting of the tidal fence was presented. It was concluded that financing for the pilot project has been granted. However, further financing for research and development is required. refs., tabs., figs.

  11. APPLICATION OF ELECTROCHEMICAL METHODS FOR DECREASING OF CHEMICAL OXYGEN DEMAND (COD AND TOTAL SUSPENDED SOLID (TSS OF TOFU INDUSTRIAL WASTEWATER

    Directory of Open Access Journals (Sweden)

    Suyata

    2015-05-01

    Full Text Available Tofu industrial wastewater has high COD and TSS level, which it cause an environmental pollution. Therefore, it is necessary to decrease the value of COD and TSS of tofu industrial wastewater before discharge into the water body. Decreasing of COD and TSS values can be carried out using an electrochemical method. The purpose of this research was to determine the effect of potential, electrode distance, pH, and time to decrease of COD and TSS value of the tofu industrial wastewater. The experiment has been performed by electrolysis tofu industrial wastewater using PbO2 as anode and Pb as cathode. The result of the research showed that under the optimum conditions of 12 V voltage, 1 cm electrode distance, pH 1, and electrolysis time of 120 minutes, decreasing COD and TSS of 96.33% and 87.87% respectively

  12. The effect of COD loading on the granule-based enhanced biological phosphorus removal system and the recoverability.

    Science.gov (United States)

    Yu, Shenjing; Sun, Peide; Zheng, Wei; Chen, Lujun; Zheng, Xiongliu; Han, Jingyi; Yan, Tao

    2014-11-01

    In this study, the effect of varied COD loading (200, 400, 500, 600 and 800 mg L(-1)) on stability and recoverability of granule-based enhanced biological phosphorus removal (EBPR) system was investigated during continuously 53-d operation. Results showed that COD loading higher than 500 mg L(-1) could obviously deteriorate the granular EBPR system and result in sludge bulking with filamentous bacteria. High COD loading also changed the transformation patterns of poly-β-hydroxyalkanoates (PHAs) and glycogen in metabolism process of polyphosphate-accumulating organisms (PAOs) and inhibited the EPS secretion, which completely destroyed the stability and integrality of granules. Results of FISH indicated that glycogen-accumulating organisms (GAOs) and other microorganisms had a competitive advantage over PAOs with higher COD loading. The community composition and EBPR performance were recovered irreversibly in long time operation when COD loading was higher than 500 mg L(-1). Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Effects of Technological Parameters and Fishing Ground on Quality Attributes of Thawed, Chilled Cod Fillets Stored in Modified Atmosphere Packaging

    DEFF Research Database (Denmark)

    Bøknæs, Niels; Østerberg, Carsten; Sørensen, Rie

    2001-01-01

    . The parameters investigated were: (1) packaging in modified atmosphere during frozen storage, (2)frozen storage period and temperature, (3),fishing ground and chill storage temperature, together with (4) the addition of trimethylamine oxide (TMAO) and sodium chloride (NaCl) to cod fillets before freezing......Effects were studied of various technological parameters and fishing ground on quality attributes of thawed, chilled cod fillets stored in modified atmosphere packaging Frozen fillets of Baltic Sea and Barents Sea cod, representing two commercial fishing grounds, were used as raw material...... of Baltic Sea cod. Therefore, addition of trimethylamine oxide and NaCl to Baltic Sea cod fillets was evaluated and shown to protect P, phosphoreum against fro::en storage inactivation and this explained the observed differences in growth of the spoilage bacteria and trimethylamine production between thawed...

  14. Oceanographic influences on the distribution of Baltic cod, Gadus morhua , during spawning in the Bornholm Basin of the Baltic Sea

    DEFF Research Database (Denmark)

    Tomkiewicz, Jonna; Lehmann, K.M.; St. John, Michael

    1998-01-01

    proportion of males to females. On the basin slopes, aggregations of cod were found near the bottom. These individuals were mainly immature and maturing stages with an increasing proportion of females to males with size. Salinity and oxygen conditions were found to be the major factors influencing...... the vertical and horizontal distribution of adult cod. Abundance of immature cod was also positively related to decreasing bottom depths. The effect of temperature was minor. The observed size- and sex-dependent spawning aggregation patterns, in association with habitat volume and stock size, may influence cod......The Baltic Sea is a stratified, semi-enclosed sea typified by a low-salinity surface layer and a deep saline layer of varying volume, salinity, temperature and oxygen concentration. The relationships between these oceanographic factors and the distribution of Baltic cod are presented, utilizing...

  15. Factors determining variations in otolith microincrement width of demersal juvenile Baltic cod Gadus morhua

    DEFF Research Database (Denmark)

    Hüssy, Karin; Mosegaard, Henrik; Hinrichsen, H.H.

    2003-01-01

    by comparison with laboratory-reared individuals, and to investigate the factors determining variation in these increments. The different increment-width patterns were identified with a method based on the widths of consecutive increments. Otolith increment widths of juvenile cod were found to be highly...

  16. Sensory characteristics of different cod products related to consumer preferences and attitudes

    NARCIS (Netherlands)

    Sveinsdottir, K.; Martinsdottir, E.; Green-Petersen, D.; Hyldig, G.; Schelvis-Smit, A.A.M.

    2009-01-01

    Quantitative descriptive analysis (QDA) was used to analyse the sensory quality of eight cod products, different with regard to origin (wild/farmed), storage time (short/extended) and storage method (fresh/frozen/packed in modified atmosphere). At the same time, 378 consumers in four European

  17. The membrane action mechanism of novel antimicrobial peptide COD isolated from the venom of bee

    Czech Academy of Sciences Publication Activity Database

    Čujová, Sabína; Slaninová, Jiřina; Fučík, Vladimír; Monincová, Lenka; Voburka, Zdeněk; Čeřovský, Václav

    2013-01-01

    Roč. 42, Suppl. 1 (2013), S164-S164 ISSN 0175-7571. [European Biophysics Congress EBSA /9./. 13.07.2013-17.07.2013, Lisbon] Institutional support: RVO:61388963 Keywords : antimicrobial peptides * COD Subject RIV: CC - Organic Chemistry

  18. The invasive ctenophore Mnemiopsis leidyi poses no direct threat to Baltic cod eggs and larvae

    DEFF Research Database (Denmark)

    Jaspers, Cornelia; Titelman, Josefin; Hansson, Lars Johan

    2011-01-01

    conducted laboratory incubation experimentsand video observations to quantify feeding rates on Baltic cod eggs and larvae. Ingestion rates increased with codlarvae concentrations up to 8 prey L21, beyond which ingestion remained constant. Neither Mnemiopsis size noregg concentration (1–16 prey L21) affected...... feeding rates on cod eggs. Observed feeding rates pooled from allexperiments conducted at nonsaturating prey concentrations were low, with the highest volume-specific clearanceon , 4.5-d-old yolk-sac larvae (0.05 6 0.02 L (mL Mnemiopsis)21 h21), and lower rates on 4.5–8-d-old larvae(0.02 6 0.02 L (m......L Mnemiopsis)21 h21) and eggs (0.02 6 0.03 L (mL Mnemiopsis)21 h21). When offered Artemiasalina and cod eggs simultaneously, Mnemiopsis passively selected against cod eggs. Video recordings showed thateggs did not trigger the capture response that Mnemiopsis shows toward motile prey, and ingested eggs were...

  19. 76 FR 15888 - Special Regulations; Areas of the National Park System, Cape Cod National Seashore

    Science.gov (United States)

    2011-03-22

    ... flora and fauna, the physiographic conditions and the historic sites and structures be permanently... wild cranberry bogs provide a glimpse into Cape Cod's past and continuing life ways. The Seashore... Military Reservation, have their own special regulations that have different dates than the standard dates...

  20. Glycolysis and ATP degradation in cod ( Gadus morhua ) at subzero temperatures in relation to thaw rigor

    DEFF Research Database (Denmark)

    Cappeln, Gertrud; Jessen, Flemming

    2001-01-01

    Glycolysis was shown to occur during freezing of cod of decrease in glycogen and an increase in lactate. In addition, the ATP content decreased during freezing. Synthesis of ATP was measured as degradation of glycogen. During storage at -9 and - 12 degreesC it was found that degradation of ATP...

  1. Eel, cod and seatrout harvest in Danish recreational fishing during 2011

    DEFF Research Database (Denmark)

    Sparrevohn, Claus Reedtz; Storr-Paulsen, Marie

    , it was estimated that 80 t [Relative standard error (RSE)=6%] eel, close to 1,300 t (RSE=5 %) cod and 400 t (RSE=5 %) seatrout (including freshwater catches) was harvested in the recreational fishery. Eel is almost exclusively taken in the passive gear fykenet fishery and seatrout was mainly caught by anglers...

  2. Nitrogen and COD removal from domestic and synthetic wastewater in subsurface-flow constructed wetlands.

    Science.gov (United States)

    Collison, R S; Grismer, M E

    2013-09-01

    Comparisons of the performance of constructed-wetland systems (CWs) for treating domestic wastewater in the laboratory and field may use pathogen-free synthetic wastewater to avoid regulatory health concerns. However, little to no data are available describing the relative treatment efficiencies of CWs to both actual and synthetic domestic wastewaters so as to enable such comparison. To fill this gap, treatment performances with respect to organics (chemical organic demand; COD) and nitrogen (ammonium and nitrate) removal from domestic (septic tank) and a similar-strength synthetic wastewater under planted and non-planted subsurface-flow CWs are determined. One pair of CWs was planted with cattails in May 2008, whereas the adjacent system was non-planted. Collected septic tank or synthesized wastewater was allowed to gravity feed each CWs, and effluent samples were collected and tested for COD and nitrogen species regularly during four different periods over six months. Overall, statistically significant greater removal of COD (-12%) and nitrogen (-5%) occurred from the synthetic as compared with the domestic wastewater from the planted and non-planted CWs. Effluent BOD5/COD ratios from the synthetic wastewater CWs averaged nearly twice that from the domestic wastewater CWs (0.17 vs 0.10), reflecting greater concentrations of readily degraded compounds. That removal fractions were consistent across the mid-range loading rates to the CWs suggests that the synthetic wastewater can be used in testing laboratory CWs with reasonable success in application of their results to the field.

  3. Influence of the COD to sulphate ratio on the anaerobic organic ...

    African Journals Online (AJOL)

    Experiments were carried out with synthetic substrate containing glucose, ammonium acetate and methanol, besides sodium bicarbonate. Micronutrients were provided by adding salts and trace metals from a stock solution. The influent chemical oxygen demand (COD) was maintained as constant as possible around 2 000 ...

  4. Dose of Biocoagulant-Mixing Rate Combinations for Optimum Reduction of COD in Wastewater

    Science.gov (United States)

    Patricia, Maria Faustina; Purwono; Budihardjo, Mochamad Arief

    2018-02-01

    Chemical oxygen demand (COD) in domestic wastewater can be treated using flocculation-coagulation process with addition of Oyster mushroom (Pleurotus ostreatus) in powder form as biocoagulant. The fungal cell wall of Oyster mushroom comprises of chitin that is high polyelectrolyte and can be function as an absorbent of heavy metals in wastewater. The effectiveness of flocculation-coagulation process in treating wastewater depends on dose of coagulant and mixing rate. Therefore, this study aims to determine the best combination of three variation of dose of biocoagulant which are 600 mg/l, 1000 mg/l, and 2000 mg/l and mixing rate which are 100 rpm, 125 rpm, and 150 rpm that give the most reduction of COD in the wastewater. The result indicates that the combination of 1000 mg/l of biocoagulant and 100 rpm of mixing rate were found to be the most optimum combination to treat COD in the wastewater with COD reduction of 47.7%.

  5. Dose of Biocoagulant-Mixing Rate Combinations for Optimum Reduction of COD in Wastewater

    Directory of Open Access Journals (Sweden)

    Faustina Patricia Maria

    2018-01-01

    Full Text Available Chemical oxygen demand (COD in domestic wastewater can be treated using flocculation-coagulation process with addition of Oyster mushroom (Pleurotus ostreatus in powder form as biocoagulant. The fungal cell wall of Oyster mushroom comprises of chitin that is high polyelectrolyte and can be function as an absorbent of heavy metals in wastewater. The effectiveness of flocculation-coagulation process in treating wastewater depends on dose of coagulant and mixing rate. Therefore, this study aims to determine the best combination of three variation of dose of biocoagulant which are 600 mg/l, 1000 mg/l, and 2000 mg/l and mixing rate which are 100 rpm, 125 rpm, and 150 rpm that give the most reduction of COD in the wastewater. The result indicates that the combination of 1000 mg/l of biocoagulant and 100 rpm of mixing rate were found to be the most optimum combination to treat COD in the wastewater with COD reduction of 47.7%.

  6. Impact of hypoxia on consumption of Baltic cod in a multispecies stock assessment context

    DEFF Research Database (Denmark)

    Teschner, E.C.; Kraus, G.; Neuenfeldt, Stefan

    2010-01-01

    The Baltic Sea is characterised by a heterogeneous oceanographic environment. The deep water layers forming the habitat of Baltic cod (Gadus morhua callarias L.) are subjected to frequently occurring pronounced anoxic conditions. Adverse oxygen conditions result in physiological stress for organi......The Baltic Sea is characterised by a heterogeneous oceanographic environment. The deep water layers forming the habitat of Baltic cod (Gadus morhua callarias L.) are subjected to frequently occurring pronounced anoxic conditions. Adverse oxygen conditions result in physiological stress...... for organisms living under these conditions. For cod e.g. a direct relationship between oxygen availability and food intake with a decreasing ingestion rate at hypoxia could be revealed. In the present study, the effects of oxygen deficiency on consumption rates were investigated and how these translate...... to stock size estimates in multi-species models. Based on results from laboratory experiments, a model was fitted to evacuation rates at different oxygen levels and integrated into the existing consumption model for Baltic cod. Individual mean oxygen corrected consumption rates were 0.1–10.9% lower than...

  7. Improvement of COD and TOC reactive dyes in textile wastewater by ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-07-06

    Jul 6, 2009 ... This study was designed to investigate the removal of reactive dyes, Samofix Red V-RBL and Samofix. Green V-G from wastewater using a two step Al (III) coagulation/activated carbon adsorption method. ... (90%) of chemical oxygen demand (COD), total organic carbon (TOC) ..... a liquid to a solid surface.

  8. Characterization of the Escherichia coli codBA operon encoding cytosine permease and cytosine deaminase

    DEFF Research Database (Denmark)

    Danielsen, S; Kilstrup, M; Barilla, K

    1992-01-01

    . A two-codon overlap between the two reading frames indicates that they constitute an operon. Transcription of the operon was found to be regulated by exogenous purines. Polypeptides specified by each of the two reading frames were expressed in minicells, and the codB gene product was found to be highly...

  9. Simultaneous removal of AOX and COD from real recycled paper wastewater using GAC-SBBR.

    Science.gov (United States)

    Osman, Wan Hasnidah Wan; Abdullah, Siti Rozaimah Sheikh; Mohamad, Abu Bakar; Kadhum, Abdul Amir H; Rahman, Rakmi Abd

    2013-05-30

    A lab-scale granular activated carbon sequencing batch biofilm reactor (GAC-SBBR), a combined adsorption and biological process, was developed to treat real wastewater from a recycled paper mill. In this study, one-consortia of mixed culture (4000-5000 mg/L) originating from recycled paper mill activated sludge from Kajang, Malaysia was acclimatized. The GAC-SBBR was fed with real wastewater taken from the same recycled paper mill, which had a high concentration of chemical oxygen demand (COD) and adsorbable organic halides (AOX). The operational duration of the GAC-SBBR was adjusted from 48 h to 24, 12 and finally 8 h to evaluate the effect of the hydraulic retention time (HRT) on the simultaneous removal of COD and AOX. The COD and AOX removals were in the range of 53-92% and 26-99%, respectively. From this study, it was observed that the longest HRT (48 h) yielded a high removal of COD and AOX, at 92% and 99%, respectively. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Challenging ICES age estimation protocols: lessons learned from the eastern Baltic cod stock

    DEFF Research Database (Denmark)

    Hüssy, Karin; Radtke, Krzysztof; Plikshs, Maris

    2016-01-01

    Over the recent decades, the International Council for the Exploration of the Sea (ICES) has set guidelines for best practise quality control of age estimation procedures. The applicability of these guidelines is assessed by reviewing the ageing issues of eastern Baltic cod (EBC) as a case study....

  11. Eastern Baltic cod in distress: biological changes and challenges for stock assessment

    DEFF Research Database (Denmark)

    Eero, Margit; Hjelm, Joakim; Behrens, Jane

    2015-01-01

    The eastern Baltic (EB) cod (Gadus morhua) stock was depleted and overexploited for decades until the mid-2000s, when fishing mortality rapidly declined and biomass started to increase, as shown by stock assessments. These positive developments were partly assigned to effective management measure...

  12. Application of a structured decision making process for nitrogen pollution management on Cape Cod

    Science.gov (United States)

    Significant release of reactive nitrogen into coastal water bodies has resulted in declining water quality in Southern New England. The Three Bays Preservation Association, in collaboration with the Cape Cod Commission, U.S. Environmental Protection Agency, and local water resou...

  13. 50 CFR Table 5 to Part 679 - Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Steller Sea Lion Protection Areas Pacific Cod Fisheries Restrictions 5 Table 5 to Part 679 Wildlife and Fisheries FISHERY CONSERVATION AND... THE EXCLUSIVE ECONOMIC ZONE OFF ALASKA Pt. 679, Table 5 Table 5 to Part 679—Steller Sea Lion...

  14. Mapping the spawning grounds of North Sea cod ( Gadus morhua ) by direct and indirect means

    DEFF Research Database (Denmark)

    Fox, C.J.; Taylor, M.; Dickey-Collas, M.

    2008-01-01

    Despite recent evidence for sub-stock structuring, North Sea cod are assessed as a single unit. As a consequence, knowledge of sub-stock trends is poor. In particular, there are no recent evaluations of which spawning grounds are active. Here we report results from the first ichthyoplankton survey...

  15. Mapping the spawning grounds of North Sea cod (Gadus morhua) by direct and indirect means

    NARCIS (Netherlands)

    Fox, C.J.; Taylor, M.; Dickey-Collas, M.; Fossum, P.; Kraus, G.; Rohlf, N.; Damme, van C.J.G.; Bolle, L.J.

    2008-01-01

    Despite recent evidence for sub-stock structuring, North Sea cod are assessed as a single unit. As a consequence, knowledge of sub-stock trends is poor. In particular, there are no recent evaluations of which spawning grounds are active. Here we report results from the first ichthyoplankton survey

  16. Evaluation of farmed cod products by a trained sensory panel and consumers in different test settings

    NARCIS (Netherlands)

    Sveinsdottir, K.; Martinsdottir, E.; Thorsdottir, F.; Schelvis-Smit, A.A.M.; Kole, A.; Thorsdottir, I.

    2010-01-01

    Sensory characteristics of farmed cod exposed to low or conventional stress levels prior to slaughter were evaluated by a trained sensory panel. Consumers in two different settings, central location test (CLT) and home-use test (HUT), also tasted the products and rated them according to overall

  17. Three-way modelling of NMR relaxation profiles from thawed cod muscle

    DEFF Research Database (Denmark)

    Jensen, Kristina Nedenskov; Guldager, Helle Skov; Jørgensen, Bo Munk

    2002-01-01

    Low-field 1H nuclear magnetic resonance transverse relaxation was used to measure water mobility and distribution in cod stored at -20°C or -30°C for up to 12 months and subsequently from 0 to 21 days in modified atmosphere at +2°C. The relaxation profiles were decomposed by parallel factor analy...

  18. Why is age determination of Baltic cod (Gadus morhua) so difficult?

    DEFF Research Database (Denmark)

    Hüssy, Karin

    2010-01-01

    to a consistent pattern the following year, and overlap was not influenced by sex or fish size. The results suggest that otolith opacity in Baltic cod is not associated with seasonal patterns in daily increment structure and that traditional age determination based on otolith opacity yields highly uncertain...

  19. Degradation of ATP and glycogen in cod ( Gadus morhua ) muscle during freezing

    DEFF Research Database (Denmark)

    Cappeln, Gertrud; Jessen, Flemming

    2001-01-01

    , the greatest decrease in ATP content was observed when the temperature reached -0.8C. Glycolysis occurred during freezing of cod as indicated by an increase in lactate content. The changes found in all measured metabolites were more pronounced when freezing was performed at a slow rate compared to a fast rate...

  20. Do North Sea cod (Gadus morhua) fisheries maintain high catch rates at low stock size?

    DEFF Research Database (Denmark)

    Rindorf, Anna; Andersen, Bo Sølgaard

    2008-01-01

    This study presents all investigation of the relationship between stock size of North Sea cod (Gadus morhua) and catch rates in seven commercial fishing fleets. The shape of the relationship was estimated using a model allowing both density-dependent changes in catchability and bias...