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Sample records for pacific salmon populations

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

    USGS Publications Warehouse

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

    1999-01-01

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

  2. Can intense predation by bears exert a depensatory effect on recruitment in a Pacific salmon population?

    PubMed

    Quinn, Thomas P; Cunningham, Curry J; Randall, Jessica; Hilborn, Ray

    2014-10-01

    It has long been recognized that, as populations increase in density, ecological processes affecting growth and survival reduce per capita recruitment in the next generation. In contrast to the evidence for such "compensatory" density dependence, the alternative "depensatory" process (reduced per capita recruitment at low density) has proven more difficult to demonstrate in the field. To test for such depensation, we measured the spawner-recruit relationship over five decades for a sockeye salmon (Oncorhynchus nerka) population in Alaska breeding in high-quality, unaltered habitat. Twenty-five years of detailed estimates of predation by brown bears, Ursus arctos, revealed strong density dependence in predation rate; the bears killed ca. 80% of the salmon in years of low salmon spawning abundance. Nevertheless, the reconstructed spawner-recruit relationship, adjusted to include salmon intercepted in the commercial fishery, provided no evidence of demographic depensation. That is, in years when few salmon returned and the great majority were killed by bears, the few that spawned were successful enough that the population remained highly productive, even when those killed by bears were included as potential spawners. We conclude that the high quality of breeding habitat at this site and the productive nature of semelparous Pacific salmon allowed this population to avoid the hypothesized depressed recruitment from depensatory processes expected at low density. The observed lack of demographic depensation is encouraging from a conservation standpoint because it implies that depleted populations may have the potential to rebound successfully given suitable spawning and rearing habitat, even in the presence of strong predation pressure.

  3. Can intense predation by bears exert a depensatory effect on recruitment in a Pacific salmon population?

    PubMed

    Quinn, Thomas P; Cunningham, Curry J; Randall, Jessica; Hilborn, Ray

    2014-10-01

    It has long been recognized that, as populations increase in density, ecological processes affecting growth and survival reduce per capita recruitment in the next generation. In contrast to the evidence for such "compensatory" density dependence, the alternative "depensatory" process (reduced per capita recruitment at low density) has proven more difficult to demonstrate in the field. To test for such depensation, we measured the spawner-recruit relationship over five decades for a sockeye salmon (Oncorhynchus nerka) population in Alaska breeding in high-quality, unaltered habitat. Twenty-five years of detailed estimates of predation by brown bears, Ursus arctos, revealed strong density dependence in predation rate; the bears killed ca. 80% of the salmon in years of low salmon spawning abundance. Nevertheless, the reconstructed spawner-recruit relationship, adjusted to include salmon intercepted in the commercial fishery, provided no evidence of demographic depensation. That is, in years when few salmon returned and the great majority were killed by bears, the few that spawned were successful enough that the population remained highly productive, even when those killed by bears were included as potential spawners. We conclude that the high quality of breeding habitat at this site and the productive nature of semelparous Pacific salmon allowed this population to avoid the hypothesized depressed recruitment from depensatory processes expected at low density. The observed lack of demographic depensation is encouraging from a conservation standpoint because it implies that depleted populations may have the potential to rebound successfully given suitable spawning and rearing habitat, even in the presence of strong predation pressure. PMID:25154755

  4. Sustainable Fisheries Management: Pacific Salmon

    USGS Publications Warehouse

    Knudsen, E. Eric; Steward, C.R.; MacDonald, Donald; Williams, J.E.

    2000-01-01

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

  5. Population differentiation in Pacific salmon: local adaptation, genetic drift, or the environment?

    USGS Publications Warehouse

    Adkison, M.D.

    1995-01-01

    Morphological, behavioral, and life-history differences between Pacific salmon (Oncorhynchus spp.) populations are commonly thought to reflect local adaptation, and it is likewise common to assume that salmon populations separated by small distances are locally adapted. Two alternatives to local adaptation exist: random genetic differentiation owing to genetic drift and founder events, and genetic homogeneity among populations, in which differences reflect differential trait expression in differing environments. Population genetics theory and simulations suggest that both alternatives are possible. With selectively neutral alleles, genetic drift can result in random differentiation despite many strays per generation. Even weak selection can prevent genetic drift in stable populations; however, founder effects can result in random differentiation despite selective pressures. Overlapping generations reduce the potential for random differentiation. Genetic homogeneity can occur despite differences in selective regimes when straying rates are high. In sum, localized differences in selection should not always result in local adaptation. Local adaptation is favored when population sizes are large and stable, selection is consistent over large areas, selective diffeentials are large, and straying rates are neither too high nor too low. Consideration of alternatives to local adaptation would improve both biological research and salmon conservation efforts.

  6. POLICY OPTIONS TO REVERSE THE DECLINE OF WILD PACIFIC SALMON

    EPA Science Inventory

    The primary goal of the Salmon 2100 Project was to identify practical options that have a high probability of maintaining biologically significant, sustainable populations of wild salmon in the Pacific Northwest and California. Wild salmon recovery efforts in western North Americ...

  7. THE SALMON 2100 PROJECT -- AN ALTERNATIVES FUTURES PERSPECTIVE ON PACIFIC NORTHWEST SALMON RECOVERY

    EPA Science Inventory

    The primary goal of the Salmon 2100 Project is to identify practical options that have a high probability of maintaining biologically significant, sustainable populations of wild salmon in the Pacific Northwest and California. Wild salmon recovery efforts in western North Americ...

  8. PACIFIC SALMON: LESSONS LEARNED FOR RECOVERING ATLANTIC SALMON

    EPA Science Inventory

    n evaluation of the history of efforts to reverse the long-term decline of Pacific Salmon provides instructive policy lessons for recovering Atlantic Salmon. From California to southern British Columbia, wild runs of Pacific salmon have universally declined and many have disappe...

  9. A TWO CENTURY HISTORY OF PACIFIC NORTHWEST SALMON: LESSONS LEARNED FOR ACHIEVING A SUSTAINABLE FUTURE

    EPA Science Inventory

    Achieving ecological sustainability is a daunting challenge. In the Pacific Northwest one of the most highly visible public policy debates concerns the future of salmon populations. Throughout the Pacific Northwest, many wild salmon stocks have declined and some have disappeare...

  10. RESTORING WILD SALMON TO THE PACIFIC NORTHWEST: CHASING AN ILLUSION

    EPA Science Inventory

    Throughout the Pacific Northwest (northern California, Oregon, Idaho, Washington, and the Columbia Basin portion of British Columbia), many wild salmon "stocks" (a group of interbreeding individuals that is roughly equivalent to a "population") have declined and some have been ...

  11. FUTURE OF PACIFIC NORTHWEST SALMON: SCIENCE AND POLICY IN ACTION

    EPA Science Inventory

    Throughout the Pacific Northwest (northern California, Oregon, Idaho, Washington, and the Columbia Basin portion of British Columbia), many wild salmon stocks (a group of interbreeding individuals that is roughly equivalent to a "population") have declined and some have disappear...

  12. PACIFIC NORTHWEST SALMON: FORECASTING THEIR STATUS IN 2100

    EPA Science Inventory

    Throughout the Pacific Northwest (northern California, Oregon, Idaho, Washington, and the Columbia Basin portion of British Columbia), many wild salmon stocks (a group of interbreeding individuals that is roughly equivalent to a "population") have declined and some have disappear...

  13. RESTORING WILD SALMON TO THE PACIFIC NORTHWEST: CHASING AN ILLUSION?

    EPA Science Inventory

    Throughout the Pacific Northwest (northern California, Oregon, Idaho, Washington, and the Columbia Basin portion of British Columbia), many wild salmon "stocks" (a group of interbreeding individuals that is roughly equivalent to a "population) have declined and some have been e...

  14. Diphyllobothriasis associated with eating raw pacific salmon.

    PubMed

    Arizono, Naoki; Yamada, Minoru; Nakamura-Uchiyama, Fukumi; Ohnishi, Kenji

    2009-06-01

    The incidence of human infection with the broad tapeworm Diphyllobothrium nihonkaiense has been increasing in urban areas of Japan and in European countries. D. nihonkaiense is morphologically similar to but genetically distinct from D. latum and exploits anadromous wild Pacific salmon as its second intermediate host. Clinical signs in humans include diarrhea and discharge of the strobila, which can be as long as 12 m. The natural life history and the geographic range of the tapeworm remain to be elucidated, but recent studies have indicated that the brown bear in the northern territories of the Pacific coast region is its natural final host. A recent surge of clinical cases highlights a change in the epidemiologic trend of this tapeworm disease from one of rural populations to a disease of urban populations worldwide who eat seafood as part of a healthy diet.

  15. THE FUTURE OF PACIFIC NORTHWEST SALMON: ANATOMY OF A CRISIS

    EPA Science Inventory

    Salmon are categorized biologically into two groups: Pacific salmon or Atlantic salmon. All seven species of Pacific salmon on both sides of the North Pacific Ocean have declined substantially from historic levels, but large runs still occur in northern British Columbia, Yukon,...

  16. Relative resistance of Pacific salmon to infectious salmon anaemia virus

    USGS Publications Warehouse

    Rolland, J.B.; Winton, J.R.

    2003-01-01

    Infectious salmon anaemia (ISA) is a major disease of Atlantic salmon, Salmo salar, caused by an orthomyxovirus (ISAV). Increases in global aqua culture and the international movement of fish made it important to determine if Pacific salmon are at risk. Steelhead trout, Oncorhynchus mykiss, and chum, O. keta, Chinook, O. tshawytscha, coho, O. kisutch, and Atlantic salmon were injected intraperitoneally with a high, medium, or low dose of a Norwegian strain of ISAV. In a second challenge, the same species, except chum salmon, were injected with a high dose of either a Canadian or the Norwegian strain. Average cumulative mortality of Atlantic salmon in trial 1 was 12% in the high dose group, 20% in the medium dose group and 16% in the low dose group. The average cumulative mortality of Atlantic salmon in trial 2 was 98%. No signs typical of ISA and no ISAV-related mortality occurred among any of the groups of Oncorhynchus spp. in either experiment, although ISAV was reisolated from some fish sampled at intervals post-challenge. The results indicate that while Oncorhynchus spp. are quite resistant to ISAV relative to Atlantic salmon, the potential for ISAV to adapt to Oncorhynchus spp. should not be ignored.

  17. Homing in Pacific salmon: mechanisms and ecological basis

    PubMed

    Dittman; Quinn

    1996-01-01

    Pacific salmon (Oncorhynchus spp.) are famous for their homing migrations from oceanic feeding grounds to their natal river to spawn. During these migrations, salmon travel through diverse habitats (e.g. oceans, lakes, rivers), each offering distinct orientation clues and, perhaps, requiring distinct sensory capabilities for navigation. Despite these challenges, homing is generally precise and this philopatry has resulted in reproductively isolated spawning populations with specialized adaptations for their natal habitat. This paper reviews the mechanisms underlying all aspects of salmon homing but emphasizes the final, freshwater phase governed by olfactory recognition of homestream water. Prior to their seaward migration, juvenile salmon learn (imprint on) odors associated with their natal site and later, as adults, use these odor memories for homing. Our understanding of this imprinting process is derived primarily from studies using artificial odorants and hatchery-reared salmon. Recent findings suggest, however, that such studies may underestimate the complexity of the imprinting process in nature.

  18. Centennial-scale fluctuations and regional complexity characterize Pacific salmon population dynamics over the past five centuries.

    PubMed

    Rogers, Lauren A; Schindler, Daniel E; Lisi, Peter J; Holtgrieve, Gordon W; Leavitt, Peter R; Bunting, Lynda; Finney, Bruce P; Selbie, Daniel T; Chen, Guangjie; Gregory-Eaves, Irene; Lisac, Mark J; Walsh, Patrick B

    2013-01-29

    Observational data from the past century have highlighted the importance of interdecadal modes of variability in fish population dynamics, but how these patterns of variation fit into a broader temporal and spatial context remains largely unknown. We analyzed time series of stable nitrogen isotopes from the sediments of 20 sockeye salmon nursery lakes across western Alaska to characterize temporal and spatial patterns in salmon abundance over the past ∼500 y. Although some stocks varied on interdecadal time scales (30- to 80-y cycles), centennial-scale variation, undetectable in modern-day catch records and survey data, has dominated salmon population dynamics over the past 500 y. Before 1900, variation in abundance was clearly not synchronous among stocks, and the only temporal signal common to lake sediment records from this region was the onset of commercial fishing in the late 1800s. Thus, historical changes in climate did not synchronize stock dynamics over centennial time scales, emphasizing that ecosystem complexity can produce a diversity of ecological responses to regional climate forcing. Our results show that marine fish populations may alternate between naturally driven periods of high and low abundance over time scales of decades to centuries and suggest that management models that assume time-invariant productivity or carrying capacity parameters may be poor representations of the biological reality in these systems. PMID:23322737

  19. Centennial-scale fluctuations and regional complexity characterize Pacific salmon population dynamics over the past five centuries

    PubMed Central

    Rogers, Lauren A.; Schindler, Daniel E.; Lisi, Peter J.; Holtgrieve, Gordon W.; Leavitt, Peter R.; Bunting, Lynda; Finney, Bruce P.; Selbie, Daniel T.; Chen, Guangjie; Gregory-Eaves, Irene; Lisac, Mark J.; Walsh, Patrick B.

    2013-01-01

    Observational data from the past century have highlighted the importance of interdecadal modes of variability in fish population dynamics, but how these patterns of variation fit into a broader temporal and spatial context remains largely unknown. We analyzed time series of stable nitrogen isotopes from the sediments of 20 sockeye salmon nursery lakes across western Alaska to characterize temporal and spatial patterns in salmon abundance over the past ∼500 y. Although some stocks varied on interdecadal time scales (30- to 80-y cycles), centennial-scale variation, undetectable in modern-day catch records and survey data, has dominated salmon population dynamics over the past 500 y. Before 1900, variation in abundance was clearly not synchronous among stocks, and the only temporal signal common to lake sediment records from this region was the onset of commercial fishing in the late 1800s. Thus, historical changes in climate did not synchronize stock dynamics over centennial time scales, emphasizing that ecosystem complexity can produce a diversity of ecological responses to regional climate forcing. Our results show that marine fish populations may alternate between naturally driven periods of high and low abundance over time scales of decades to centuries and suggest that management models that assume time-invariant productivity or carrying capacity parameters may be poor representations of the biological reality in these systems. PMID:23322737

  20. Centennial-scale fluctuations and regional complexity characterize Pacific salmon population dynamics over the past five centuries.

    PubMed

    Rogers, Lauren A; Schindler, Daniel E; Lisi, Peter J; Holtgrieve, Gordon W; Leavitt, Peter R; Bunting, Lynda; Finney, Bruce P; Selbie, Daniel T; Chen, Guangjie; Gregory-Eaves, Irene; Lisac, Mark J; Walsh, Patrick B

    2013-01-29

    Observational data from the past century have highlighted the importance of interdecadal modes of variability in fish population dynamics, but how these patterns of variation fit into a broader temporal and spatial context remains largely unknown. We analyzed time series of stable nitrogen isotopes from the sediments of 20 sockeye salmon nursery lakes across western Alaska to characterize temporal and spatial patterns in salmon abundance over the past ∼500 y. Although some stocks varied on interdecadal time scales (30- to 80-y cycles), centennial-scale variation, undetectable in modern-day catch records and survey data, has dominated salmon population dynamics over the past 500 y. Before 1900, variation in abundance was clearly not synchronous among stocks, and the only temporal signal common to lake sediment records from this region was the onset of commercial fishing in the late 1800s. Thus, historical changes in climate did not synchronize stock dynamics over centennial time scales, emphasizing that ecosystem complexity can produce a diversity of ecological responses to regional climate forcing. Our results show that marine fish populations may alternate between naturally driven periods of high and low abundance over time scales of decades to centuries and suggest that management models that assume time-invariant productivity or carrying capacity parameters may be poor representations of the biological reality in these systems.

  1. Multivariate Models of Adult Pacific Salmon Returns

    PubMed Central

    Burke, Brian J.; Peterson, William T.; Beckman, Brian R.; Morgan, Cheryl; Daly, Elizabeth A.; Litz, Marisa

    2013-01-01

    Most modeling and statistical approaches encourage simplicity, yet ecological processes are often complex, as they are influenced by numerous dynamic environmental and biological factors. Pacific salmon abundance has been highly variable over the last few decades and most forecasting models have proven inadequate, primarily because of a lack of understanding of the processes affecting variability in survival. Better methods and data for predicting the abundance of returning adults are therefore required to effectively manage the species. We combined 31 distinct indicators of the marine environment collected over an 11-year period into a multivariate analysis to summarize and predict adult spring Chinook salmon returns to the Columbia River in 2012. In addition to forecasts, this tool quantifies the strength of the relationship between various ecological indicators and salmon returns, allowing interpretation of ecosystem processes. The relative importance of indicators varied, but a few trends emerged. Adult returns of spring Chinook salmon were best described using indicators of bottom-up ecological processes such as composition and abundance of zooplankton and fish prey as well as measures of individual fish, such as growth and condition. Local indicators of temperature or coastal upwelling did not contribute as much as large-scale indicators of temperature variability, matching the spatial scale over which salmon spend the majority of their ocean residence. Results suggest that effective management of Pacific salmon requires multiple types of data and that no single indicator can represent the complex early-ocean ecology of salmon. PMID:23326586

  2. Infectious diseases of Pacific salmon

    USGS Publications Warehouse

    1954-01-01

    A variety of bacteria has been found responsible for outbreaks of disease in salmon in sea water. The most important of these is a species of Vibrio. Tuberculosis has been found in adult chinook salmon and the evidence indicates that the disease was contracted at sea.

  3. Adaptive potential of a Pacific salmon challenged by climate change

    NASA Astrophysics Data System (ADS)

    Muñoz, Nicolas J.; Farrell, Anthony P.; Heath, John W.; Neff, Bryan D.

    2015-02-01

    Pacific salmon provide critical sustenance for millions of people worldwide and have far-reaching impacts on the productivity of ecosystems. Rising temperatures now threaten the persistence of these important fishes, yet it remains unknown whether populations can adapt. Here, we provide the first evidence that a Pacific salmon has both physiological and genetic capacities to increase its thermal tolerance in response to rising temperatures. In juvenile chinook salmon (Oncorhynchus tshawytscha), a 4 °C increase in developmental temperature was associated with a 2 °C increase in key measures of the thermal performance of cardiac function. Moreover, additive genetic effects significantly influenced several measures of cardiac capacity, indicative of heritable variation on which selection can act. However, a lack of both plasticity and genetic variation was found for the arrhythmic temperature of the heart, constraining this upper thermal limit to a maximum of 24.5 +/- 2.2 °C. Linking this constraint on thermal tolerance with present-day river temperatures and projected warming scenarios, we predict a 17% chance of catastrophic loss in the population by 2100 based on the average warming projection, with this chance increasing to 98% in the maximum warming scenario. Climate change mitigation is thus necessary to ensure the future viability of Pacific salmon populations.

  4. SCIENCE, POLICY, AND PACIFIC NORTHWEST SALMON RECOVERY

    EPA Science Inventory

    Throughout the Pacific Northwest, since 1850, all wild salmon runs have declined and some have disappeared. Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline. Each year, hundreds of millions of dollars continue to be spent in variou...

  5. SCIENCE, POLITICS, AND PACIFIC NORTHWEST SALMON RECOVERY

    EPA Science Inventory

    Throughout the Pacific Northwest, since 1850, all wild salmon runs have declined and some have disappeared. Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline. Each year, hundreds of millions of dollars continue to be spent in variou...

  6. POLICY CONUNDRUM: RESTORING WILD SALMON TO THE PACIFIC NORTHWEST

    EPA Science Inventory

    Restoring wild salmon runs to the Pacific Northwest is technically challenging, politically nasty, and socially divisive. Past restoration efforts have been largely unsuccessful. Society's failure to reverse the continuing decline of wild salmon has the characteristics of a pol...

  7. Time-Delayed Subsidies: Interspecies Population Effects in Salmon

    PubMed Central

    Nelson, Michelle C.; Reynolds, John D.

    2014-01-01

    Cross-boundary nutrient inputs can enhance and sustain populations of organisms in nutrient-poor recipient ecosystems. For example, Pacific salmon (Oncorhynchus spp.) can deliver large amounts of marine-derived nutrients to freshwater ecosystems through their eggs, excretion, or carcasses. This has led to the question of whether nutrients from one generation of salmon can benefit juvenile salmon from subsequent generations. In a study of 12 streams on the central coast of British Columbia, we found that the abundance of juvenile coho salmon was most closely correlated with the abundance of adult pink salmon from previous years. There was a secondary role for adult chum salmon and watershed size, followed by other physical characteristics of streams. Most of the coho sampled emerged in the spring, and had little to no direct contact with spawning salmon nutrients at the time of sampling in the summer and fall. A combination of techniques suggest that subsidies from spawning salmon can have a strong, positive, time-delayed influence on the productivity of salmon-bearing streams through indirect effects from previous spawning events. This is the first study on the impacts of nutrients from naturally-occurring spawning salmon on juvenile population abundance of other salmon species. PMID:24911974

  8. Competition between Asian pink salmon (Oncorhynchus gorbuscha) and Alaskan sockeye salmon (O. nerka) in the North Pacific Ocean

    USGS Publications Warehouse

    Ruggerone, G.T.; Zimmermann, M.; Myers, K.W.; Nielsen, J.L.; Rogers, D.E.

    2003-01-01

    The importance of interspecific competition as a mechanism regulating population abundance in offshore marine communities is largely unknown. We evaluated offshore competition between Asian pink salmon and Bristol Bay (Alaska) sockeye salmon, which intermingle in the North Pacific Ocean and Bering Sea, using the unique biennial abundance cycle of Asian pink salmon from 1955 to 2000. Sockeye salmon growth during the second and third growing seasons at sea, as determined by scale measurements, declined significantly in odd-numbered years, corresponding to years when Asian pink salmon are most abundant. Bristol Bay sockeye salmon do not interact with Asian pink salmon during their first summer and fall seasons and no difference in first year scale growth was detected. The interaction with odd-year pink salmon led to significantly smaller size at age of adult sockeye salmon, especially among younger female salmon. Examination of sockeye salmon smolt to adult survival rates during 1977-97 indicated that smolts entering the ocean during even-numbered years and interacting with abundant odd-year pink salmon during the following year experienced 26% (age-2 smolt) to 45% (age-1 smolt) lower survival compared with smolts migrating during odd-numbered years. Adult sockeye salmon returning to Bristol Bay from even-year smolt migrations were 22% less abundant (reduced by 5.9 million fish per year) compared with returns from odd-year migrations. The greatest reduction in adult returns occurred among adults spending 2 compared with 3 years at sea. Our new evidence for interspecific competition highlights the need for multispecies, international management of salmon production, including salmon released from hatcheries into the ocean.

  9. Relationship of farm salmon, sea lice, and wild salmon populations.

    PubMed

    Marty, Gary D; Saksida, Sonja M; Quinn, Terrance J

    2010-12-28

    Increased farm salmon production has heightened concerns about the association between disease on farm and wild fish. The controversy is particularly evident in the Broughton Archipelago of Western Canada, where a high prevalence of sea lice (ectoparasitic copepods) was first reported on juvenile wild pink salmon (Oncorhynchus gorbuscha) in 2001. Exposure to sea lice from farmed Atlantic salmon (Salmo salar) was thought to be the cause of the 97% population decline before these fish returned to spawn in 2002, although no diagnostic investigation was done to rule out other causes of mortality. To address the concern that sea lice from fish farms would cause population extinction of wild salmon, we analyzed 10-20 y of fish farm data and 60 y of pink salmon data. We show that the number of pink salmon returning to spawn in the fall predicts the number of female sea lice on farm fish the next spring, which, in turn, accounts for 98% of the annual variability in the prevalence of sea lice on outmigrating wild juvenile salmon. However, productivity of wild salmon is not negatively associated with either farm lice numbers or farm fish production, and all published field and laboratory data support the conclusion that something other than sea lice caused the population decline in 2002. We conclude that separating farm salmon from wild salmon--proposed through coordinated fallowing or closed containment--will not increase wild salmon productivity and that medical analysis can improve our understanding of complex issues related to aquaculture sustainability.

  10. Changing central Pacific El Niños reduce stability of North American salmon survival rates

    PubMed Central

    Kilduff, D. Patrick; Di Lorenzo, Emanuele; Botsford, Louis W.; Teo, Steven L. H.

    2015-01-01

    Pacific salmon are a dominant component of the northeast Pacific ecosystem. Their status is of concern because salmon abundance is highly variable—including protected stocks, a recently closed fishery, and actively managed fisheries that provide substantial ecosystem services. Variable ocean conditions, such as the Pacific Decadal Oscillation (PDO), have influenced these fisheries, while diminished diversity of freshwater habitats have increased variability via the portfolio effect. We address the question of how recent changes in ocean conditions will affect populations of two salmon species. Since the 1980s, El Niño Southern Oscillation (ENSO) events have been more frequently associated with central tropical Pacific warming (CPW) rather than the canonical eastern Pacific warming ENSO (EPW). CPW is linked to the North Pacific Gyre Oscillation (NPGO), whereas EPW is linked to the PDO, different indicators of northeast Pacific Ocean ecosystem productivity. Here we show that both coho and Chinook salmon survival rates along western North America indicate that the NPGO, rather than the PDO, explains salmon survival since the 1980s. The observed increase in NPGO variance in recent decades was accompanied by an increase in coherence of local survival rates of these two species, increasing salmon variability via the portfolio effect. Such increases in coherence among salmon stocks are usually attributed to controllable freshwater influences such as hatcheries and habitat degradation, but the unknown mechanism underlying the ocean climate effect identified here is not directly subject to management actions. PMID:26240365

  11. Changing central Pacific El Niños reduce stability of North American salmon survival rates.

    PubMed

    Kilduff, D Patrick; Di Lorenzo, Emanuele; Botsford, Louis W; Teo, Steven L H

    2015-09-01

    Pacific salmon are a dominant component of the northeast Pacific ecosystem. Their status is of concern because salmon abundance is highly variable--including protected stocks, a recently closed fishery, and actively managed fisheries that provide substantial ecosystem services. Variable ocean conditions, such as the Pacific Decadal Oscillation (PDO), have influenced these fisheries, while diminished diversity of freshwater habitats have increased variability via the portfolio effect. We address the question of how recent changes in ocean conditions will affect populations of two salmon species. Since the 1980s, El Niño Southern Oscillation (ENSO) events have been more frequently associated with central tropical Pacific warming (CPW) rather than the canonical eastern Pacific warming ENSO (EPW). CPW is linked to the North Pacific Gyre Oscillation (NPGO), whereas EPW is linked to the PDO, different indicators of northeast Pacific Ocean ecosystem productivity. Here we show that both coho and Chinook salmon survival rates along western North America indicate that the NPGO, rather than the PDO, explains salmon survival since the 1980s. The observed increase in NPGO variance in recent decades was accompanied by an increase in coherence of local survival rates of these two species, increasing salmon variability via the portfolio effect. Such increases in coherence among salmon stocks are usually attributed to controllable freshwater influences such as hatcheries and habitat degradation, but the unknown mechanism underlying the ocean climate effect identified here is not directly subject to management actions. PMID:26240365

  12. Evolutionary history of Pacific salmon in dynamic environments

    PubMed Central

    Waples, Robin S; Pess, George R; Beechie, Tim

    2008-01-01

    Contemporary evolution of Pacific salmon (Oncorhynchus spp.) is best viewed in the context of the evolutionary history of the species and the dynamic ecosystems they inhabit. Speciation was complete by the late Miocene, leaving c. six million years for intraspecific diversification. Following the most recent glacial maximum, large areas became available for recolonization. Current intraspecific diversity is thus the product of recent evolution overlaid onto divergent historical lineages forged during recurrent episodes of Pleistocene glaciation. In northwestern North America, dominant habitat features have been relatively stable for the past 5000 years, but salmon ecosystems remain dynamic because of disturbance regimes (volcanic eruptions, landslides, wildfires, floods, variations in marine and freshwater productivity) that occur on a variety of temporal and spatial scales. These disturbances both create selective pressures for adaptive responses by salmon and inhibit long-term divergence by periodically extirpating local populations and creating episodic dispersal events that erode emerging differences. Recent anthropogenic changes are replicated pervasively across the landscape and interrupt processes that allow natural habitat recovery. If anthropogenic changes can be shaped to produce disturbance regimes that more closely mimic (in both space and time) those under which the species evolved, Pacific salmon should be well-equipped to deal with future challenges, just as they have throughout their evolutionary history. PMID:25567626

  13. Evolutionary history of Pacific salmon in dynamic environments.

    PubMed

    Waples, Robin S; Pess, George R; Beechie, Tim

    2008-05-01

    Contemporary evolution of Pacific salmon (Oncorhynchus spp.) is best viewed in the context of the evolutionary history of the species and the dynamic ecosystems they inhabit. Speciation was complete by the late Miocene, leaving c. six million years for intraspecific diversification. Following the most recent glacial maximum, large areas became available for recolonization. Current intraspecific diversity is thus the product of recent evolution overlaid onto divergent historical lineages forged during recurrent episodes of Pleistocene glaciation. In northwestern North America, dominant habitat features have been relatively stable for the past 5000 years, but salmon ecosystems remain dynamic because of disturbance regimes (volcanic eruptions, landslides, wildfires, floods, variations in marine and freshwater productivity) that occur on a variety of temporal and spatial scales. These disturbances both create selective pressures for adaptive responses by salmon and inhibit long-term divergence by periodically extirpating local populations and creating episodic dispersal events that erode emerging differences. Recent anthropogenic changes are replicated pervasively across the landscape and interrupt processes that allow natural habitat recovery. If anthropogenic changes can be shaped to produce disturbance regimes that more closely mimic (in both space and time) those under which the species evolved, Pacific salmon should be well-equipped to deal with future challenges, just as they have throughout their evolutionary history. PMID:25567626

  14. PACIFIC SALMON FISHERIES OF THE WORLD: STATUS, PROSPECTS, AND CHALLENGES

    EPA Science Inventory

    All seven species of Pacific salmon on both sides of the North Pacific have declined significantly from historic levels, but not as dramatically as have Atlantic salmon. Hatchery production has been used to maintain some runs in the southern region of the range (e.g., Japan, Kor...

  15. POLICY CONUNDRUM: RESTORING WILD SALMON TO THE PACIFIC NORTHWEST

    EPA Science Inventory

    Across the Pacific Northwest region of North America, many runs of wild (in contrast to hatchery-bred) salmon have declined and some have been extirpated. Restoring wild salmon runs to the Pacific Northwest is technically challenging, politically nasty, socially divisive, and ...

  16. NORTH PACIFIC SALMON MONITORING WORKSHOP I - SUMMARY REPORT

    EPA Science Inventory

    The intent of the first North Pacific Salmon Monitoring Workshop was to initiate development of an economically feasible monitoring strategy that could serve as a warning system for detecting changes in the status of Pacific Rim salmon. This is a summary of the workshop held Fe...

  17. Impacts of Climatic Change and Fishing on Pacific Salmon Abundance Over the Past 300 Years

    NASA Astrophysics Data System (ADS)

    Finney, Bruce P.; Gregory-Eaves, Irene; Sweetman, Jon; Douglas, Marianne S. V.; Smol, John P.

    2000-10-01

    The effects of climate variability on Pacific salmon abundance are uncertain because historical records are short and are complicated by commercial harvesting and habitat alteration. We use lake sediment records of δ15N and biological indicators to reconstruct sockeye salmon abundance in the Bristol Bay and Kodiak Island regions of Alaska over the past 300 years. Marked shifts in populations occurred over decades during this period, and some pronounced changes appear to be related to climatic change. Variations in salmon returns due to climate or harvesting can have strong impacts on sockeye nursery lake productivity in systems where adult salmon carcasses are important nutrient sources.

  18. Range-wide selection of catchments for Pacific salmon conservation.

    PubMed

    Pinsky, Malin L; Springmeyer, Dane B; Goslin, Matthew N; Augerot, Xanthippe

    2009-06-01

    Freshwater ecosystems are declining in quality globally, but a lack of data inhibits identification of areas valuable for conservation across national borders. We developed a biological measure of conservation value for six species of Pacific salmon (Oncorhynchus spp.) in catchments of the northern Pacific across Canada, China, Japan, Russia, and the United States. We based the measure on abundance and life-history richness and a model-based method that filled data gaps. Catchments with high conservation value ranged from California to northern Russia and included catchments in regions that are strongly affected by human development (e.g., Puget Sound). Catchments with high conservation value were less affected by agriculture and dams than other catchments, although only 1% were within biodiversity reserves. Our set of high-value areas was largely insensitive to simulated error, although classification remained uncertain for 3% of catchments. Although salmon face many threats, we propose they will be most likely to exhibit resilience into the future if a complementary mosaic of conservation strategies can be proactively adopted in catchments with healthy salmon populations. Our analysis provides an initial map of where these catchments are likely to be located. PMID:19220368

  19. Ecology. Pacific salmon run hot and cold.

    PubMed

    Brown, K

    2000-10-27

    Using a novel technique, described on page 795, paleoceanographers have been able to chart the abundance of sockeye salmon in the Bristol Bay and Kodiak Island regions of Alaska over the past 300 years--by far the most complete record yet. Through time, they found, sockeye populations have alternately soared and slipped, following natural climate variations--well before commercial fishers began throwing nets over the sides of boats.

  20. Effects of introduced fishes on wild juvenile coho salmon in three shallow pacific northwest lakes

    USGS Publications Warehouse

    Bonar, Scott A.; Bolding, B.D.; Divens, M.; Meyer, W.

    2005-01-01

    Declines in Pacific salmon Oncorhynchus spp. have been blamed on hydropower, overfishing, ocean conditions, and land use practices; however, less is known about the impacts of introduced fish. Most of the hundreds of lakes and ponds in the Pacific Northwest contain introduced fishes, and many of these water bodies are also important for salmon production, especially of coho salmon O. kisutch. Over 2 years, we examined the predation impacts of 10 common introduced fishes (brown bullhead Ameiurus nebulosus, black crappie Pomoxis nigro-maculatus, bluegill Lepomis macrochirus, golden shiner Notemigonus crysoleucas, green sunfish L. cyanellus, largemouth bass Micropterus salmoides, pumpkinseed L. gibbosus, rainbow trout O. mykiss, warmouth L. gulosus, and yellow perch Perca flavescens) and two native fishes (cutthroat trout O. clarkii and prickly sculpin Cottus asper) on wild juvenile coho salmon in three shallow Pacific Northwest lakes, all located in different watersheds. Of these species, largemouth bass were responsible for an average of 98% of the predation on coho salmon in all lakes, but the total impact to each run varied among lakes and years. Very few coho salmon were eaten by black crappies, brown bullheads, cutthroat trout, prickly sculpin, or yellow perch, whereas other species were not observed to eat coho salmon. Juvenile coho salmon growth in all lakes was higher than in nearby streams. Therefore, food competition between coho salmon and introduced fishes in lakes was probably not limiting coho salmon populations. Largemouth bass are widespread and are present in 85% of lowland warmwater public-access lakes in Washington (n = 421), 84% of those in Oregon (n = 179), and 74% of those in the eight northwesternmost counties in California (n = 19). Future research would help to identify the impact of largemouth bass predation across the region and prioritize lakes where impacts are most severe. Nevertheless, attempts to transplant or increase largemouth bass

  1. RESTORING SALMON TO THE PACIFIC NORTHWEST: LEGACIES, CHOICES, AND TRAJECTORIES

    EPA Science Inventory

    The general policy goal of protecting and restoring runs of wild Pacific salmon enjoys wide public support. Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline of wild salmon in the western contiguous United States. Of the Earth's fou...

  2. PACIFIC NORTHWEST SALMON: IN SEARCH OF A SUSTAINABLE FUTURE

    EPA Science Inventory

    Throughout the Pacific Northwest, all wild salmon runs have declined since 1850 and some have disappeared. A sustainable future for wild salmon remains elusive. Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline. Each year, hundreds...

  3. PACIFIC NORTHWEST SALMON: THE MOST LIKELY FUTURE AND SOME ALTERNATIVES

    EPA Science Inventory

    Throughout the Pacific Northwest, all wild salmon runs have declined since 1850 and some have disappeared. A sustainable future for wild salmon remains elusive. Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline. Each year, hundreds of...

  4. Predation by fallfish (Semotilus corporalis) on Pacific salmon eggs in the Salmon River, New York

    USGS Publications Warehouse

    Johnson, J.H.; Nack, C.C.; Chalupnicki, M.A.

    2009-01-01

    Fallfish (Semotilus corporalis) are the largest native cyprinid in the northeastern United States and are the most abundant native species in the Salmon River, New York. The Salmon River is a high-quality spawning and nursery river for Pacific salmon (Oncorhynchus spp.) migrating from Lake Ontario. Because of the large number of Pacific salmon spawning in the river in the fall extensive redd superimposition occurs resulting in salmonid eggs being available on the substrate. We examined the fall diet of 647 fallfish in 2007 and 2008 to determine the extent of predation on Pacific salmon eggs. The contribution of eggs in the diet significantly increased once fallfish attained a size of 100 mm total length. The largest size category of fallfish examined (≥150 mm) had the highest proportion (86.1%) of salmon eggs in their diet. The contribution of Zooplankton and chironomids in the diet of fallfish decreased with fish size. Except for the two largest groups of fallfish examined (i.e., 100–149 mm and ≥150 mm) diet overlap among size groups was low. The high contribution in the diet during the fall and high caloric value of Pacific salmon eggs could increase growth and survival of this species in the Salmon River.

  5. On signals of phase transitions in salmon population dynamics.

    PubMed

    Krkošek, Martin; Drake, John M

    2014-06-01

    Critical slowing down (CSD) reflects the decline in resilience of equilibria near a bifurcation and may reveal early warning signals (EWS) of ecological phase transitions. We studied CSD in the recruitment dynamics of 120 stocks of three Pacific salmon (Oncorhynchus spp.) species in relation to critical transitions in fishery models. Pink salmon (Oncorhynchus gorbuscha) exhibited increased variability and autocorrelation in populations that had a growth parameter, r, close to zero, consistent with EWS of extinction. However, models and data for sockeye salmon (Oncorhynchus nerka) indicate that portfolio effects from heterogeneity in age-at-maturity may obscure EWS. Chum salmon (Oncorhynchus keta) show intermediate results. The data do not reveal EWS of Ricker-type bifurcations that cause oscillations and chaos at high r. These results not only provide empirical support for CSD in some ecological systems, but also indicate that portfolio effects of age structure may conceal EWS of some critical transitions. PMID:24759855

  6. Concentrations of trace elements in Pacific and Atlantic salmon

    NASA Astrophysics Data System (ADS)

    Khristoforova, N. K.; Tsygankov, V. Yu.; Boyarova, M. D.; Lukyanova, O. N.

    2015-09-01

    Concentrations of Hg, As, Cd, Pb, Zn, and Cu were analyzed in the two most abundant species of Pacific salmon, chum and pink salmon, caught in the Kuril Islands at the end of July, 2013. The concentrations of toxic elements (Hg, As, Pb, Cd) in males and females of these species are below the maximum permissible concentrations for seafood. It was found that farmed filleted Atlantic salmon are dominated by Zn and Cu, while muscles of wild salmon are dominated by Pb. Observed differences are obviously related to peculiar environmental geochemical conditions: anthropogenic impact for Atlantic salmon grown in coastal waters and the influence of the natural factors volcanism and upwelling for wild salmon from the Kuril waters.

  7. 76 FR 54216 - Pacific Fishery Management Council (Council); Work Session To Review Proposed Salmon Methodology...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-31

    ...); Work Session To Review Proposed Salmon Methodology Changes AGENCY: National Marine Fisheries Service... meeting. SUMMARY: The Pacific Fishery Management Council's Salmon Technical Team (STT), Scientific and Statistical Committee (SSC) Salmon Subcommittee, and Model Evaluation Workgroup (MEW) will review...

  8. 77 FR 58526 - Pacific Fishery Management Council; Public Meeting; Work Session To Review Proposed Salmon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-21

    ... Meeting; Work Session To Review Proposed Salmon Methodology Changes AGENCY: National Marine Fisheries... public meeting. SUMMARY: The Pacific Fishery Management Council's Salmon Technical Team (STT), Scientific and Statistical Committee (SSC) Salmon Subcommittee, and Model Evaluation Workgroup (MEW) will...

  9. SALMON 2100: THE FUTURE OF WILD PACIFIC SALMON

    EPA Science Inventory

    Many experts have concluded that wild salmon recovery efforts in western North America (especially California, Oregon, Washington, Idaho, and southern British Columbia), as earnest, expensive, and socially disruptive as they currently are, do not appear likely to sustain biologic...

  10. Research on Captive Broodstock Technology for Pacific Salmon, 1995 Annual Report.

    SciTech Connect

    Swanson, Penny; Pascho, Ronald; Hershberger, William K.

    1996-01-01

    This report summarizes research on captive broodstock technologies conducted during 1995 under Bonneville Power Administration Project 93-56. Investigations were conducted by the National Marine Fisheries Service (NMFS) in cooperation with the US Fish and Wildlife Service, University of Washington, and Northwest Biological Science Center (US Geological Survey). Studies encompassed several categories of research, including fish husbandry, reproductive physiology, immunology, pathology, nutrition, and genetics. Captive broodstock programs are being developed and implemented to aid recovery of endangered Pacific salmon stocks. Like salmon hatchery programs, however, captive broodstock programs are not without problems and risks to natural salmon populations. The research projects described in this report were developed in part based on a literature review, Assessment of the Status of Captive Broodstock Technology for Pacific Salmon. The work was divided into three major research areas: (1) research on sockeye salmon; (2) research on spring chinook salmon; and (3) research on quantitative genetic problems associated with captive broodstock programs. Investigations of nutrition, reproductive physiology, fish husbandry, and fish health were integrated into the research on sockeye and spring chinook salmon. A description of each investigation and its major findings and conclusions is presented.

  11. Salmon blood plasma: effective inhibitor of protease-laden Pacific whiting surimi and salmon mince.

    PubMed

    Fowler, Matthew R; Park, Jae W

    2015-06-01

    The effect of salmon plasma (SP) from Chinook salmon on proteolytic inhibition was investigated. SP was found to inhibit both cysteine and serine proteases as well as protease extracted from Pacific whiting muscle. SP was found to contain a 55kDa cysteine protease inhibitor through SDS-PAGE inhibitor staining. Freeze dried salmon plasma (FSP) and salmon plasma concentrated by ultrafiltration (CSP) were tested for their ability to inhibit autolysis in Pacific whiting surimi and salmon mince at concentrations of 0.25%, 0.5%, 1%, and 2%. Pacific whiting surimi autolysis was inhibited by an average of 89% regardless of concentration while inhibition of salmon mince autolysis increased with concentration (p<0.05). CSP performed slightly better than FSP at inhibiting salmon mince autolysis (p<0.05). Serine protease inhibition decreased when SP heated above 40°C but was stable across a broad NaCl and pH range. Cysteine protease inhibitors exhibited good temperature, NaCl, and pH stability. PMID:25624255

  12. Incorporating catastrophic risk assessments into setting conservation goals for threatened Pacific salmon.

    PubMed

    Good, Thomas P; Davies, Jeremy; Burke, Brian J; Ruckelshaus, Mary H

    2008-01-01

    Catastrophic die-offs can have important consequences for vertebrate population growth and biodiversity, but catastrophic risks are not commonly incorporated into endangered-species recovery planning. Natural (e.g., landslides, floods) and anthropogenic (e.g., toxic leaks and spills) catastrophes pose a challenge for evolutionarily significant units (ESUs) of Pacific salmon listed under the Endangered Species Act and teetering at precariously low population levels. To spread risks among Puget Sound chinook salmon populations, recovery strategies for ESU-wide viability recommend at least two viable populations of historical life-history types in each of five geographic regions. We explored the likelihood of Puget Sound chinook salmon ESU persistence by examining spatial patterns of catastrophic risk and testing ESU viability recommendations for 22 populations of the threatened Puget Sound chinook salmon ESU. We combined geospatial information about catastrophic risks and chinook salmon distribution in Puget Sound watersheds to categorize relative catastrophic risks for each population. We then analyzed similarities in risk scores among regions and compared risk distributions among strategies: (1) population groups selected using the ESU viability recommendations of having populations spread out geographically and including historical life-history diversity, and (2) population groups selected at random. Risks from individual catastrophes varied among populations, but overall risk from catastrophes was similar within geographic regions. Recovery strategies that called for two viable populations in each of five geographic regions had lower risk than random strategies; strategies that included life-history diversity had even lower risks. Geographically distributed populations have varying catastrophic-risks profiles, thus identifying and reinforcing the spatial and life-history diversity critical for populations to respond to environmental change or needed to rescue

  13. Techno-Arrogance and Halfway Technologies: Salmon Hatcheries on the Pacific Coast of North America.

    ERIC Educational Resources Information Center

    Meffe, Gary K.

    1993-01-01

    Discusses an attempt to recover Pacific salmonid fisheries with hatcheries as an example of a human attitude toward nature that places technological mastery over nature at the forefront of our approach to many environmental problems. Points out how this approach addresses the symptoms but not the causes of the salmon population decline. Suggests…

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

    PubMed

    Drake, D C; Naiman, Robert J

    2007-07-01

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

  15. Comment on "Declining wild salmon populations in relation to parasites from farm salmon".

    PubMed

    Riddell, Brian E; Beamish, Richard J; Richards, Laura J; Candy, John R

    2008-12-19

    Krkosek et al. (Reports, 14 December 2007, p. 1772) claimed that sea lice spread from salmon farms placed wild pink salmon populations "on a trajectory toward rapid local extinction." Their prediction is inconsistent with observed pink salmon returns and overstates the risks from sea lice and salmon farming.

  16. Declining wild salmon populations in relation to parasites from farm salmon.

    PubMed

    Krkosek, Martin; Ford, Jennifer S; Morton, Alexandra; Lele, Subhash; Myers, Ransom A; Lewis, Mark A

    2007-12-14

    Rather than benefiting wild fish, industrial aquaculture may contribute to declines in ocean fisheries and ecosystems. Farm salmon are commonly infected with salmon lice (Lepeophtheirus salmonis), which are native ectoparasitic copepods. We show that recurrent louse infestations of wild juvenile pink salmon (Oncorhynchus gorbuscha), all associated with salmon farms, have depressed wild pink salmon populations and placed them on a trajectory toward rapid local extinction. The louse-induced mortality of pink salmon is commonly over 80% and exceeds previous fishing mortality. If outbreaks continue, then local extinction is certain, and a 99% collapse in pink salmon population abundance is expected in four salmon generations. These results suggest that salmon farms can cause parasite outbreaks that erode the capacity of a coastal ecosystem to support wild salmon populations.

  17. Analyzing variations in life-history traits of Pacific salmon in the context of Dynamic Energy Budget (DEB) theory

    NASA Astrophysics Data System (ADS)

    Pecquerie, Laure; Johnson, Leah R.; Kooijman, Sebastiaan A. L. M.; Nisbet, Roger M.

    2011-11-01

    To determine the response of Pacific salmon ( Oncorhynchus spp.) populations to environmental change, we need to understand impacts on all life stages. However, an integrative and mechanistic approach is particularly challenging for Pacific salmon as they use multiple habitats (river, estuarine and marine) during their life cycle. Here we develop a bioenergetic model that predicts development, growth and reproduction of a Pacific salmon in a dynamic environment, from an egg to a reproducing female, and that links female state to egg traits. This model uses Dynamic Energy Budget (DEB) theory to predict how life history traits vary among five species of Pacific salmon: Pink, Sockeye, Coho, Chum and Chinook. Supplemented with a limited number of assumptions on anadromy and semelparity and external signals for migrations, the model reproduces the qualitative patterns in egg size, fry size and fecundity both at the inter- and intra-species levels. Our results highlight how modeling all life stages within a single framework enables us to better understand complex life-history patterns. Additionally we show that body size scaling relationships implied by DEB theory provide a simple way to transfer model parameters among Pacific salmon species, thus providing a generic approach to study the impact of environmental conditions on the life cycle of Pacific salmon.

  18. 21 CFR 161.170 - Canned Pacific salmon.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... sealed containers and so processed by heat as to prevent spoilage and soften bones. The food is labeled... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Canned Pacific salmon. 161.170 Section 161.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  19. 21 CFR 161.170 - Canned Pacific salmon.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... sealed containers and so processed by heat as to prevent spoilage and soften bones. The food is labeled... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Canned Pacific salmon. 161.170 Section 161.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  20. 21 CFR 161.170 - Canned Pacific salmon.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... sealed containers and so processed by heat as to prevent spoilage and soften bones. The food is labeled... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Canned Pacific salmon. 161.170 Section 161.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  1. 21 CFR 161.170 - Canned Pacific salmon.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... sealed containers and so processed by heat as to prevent spoilage and soften bones. The food is labeled... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Canned Pacific salmon. 161.170 Section 161.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  2. 21 CFR 161.170 - Canned Pacific salmon.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... sealed containers and so processed by heat as to prevent spoilage and soften bones. The food is labeled... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Canned Pacific salmon. 161.170 Section 161.170 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  3. Freshwater ecosystems and resilience of Pacific salmon: Habitat Management based on natural variability

    USGS Publications Warehouse

    Bisson, P.A.; Dunham, J.B.; Reeves, G.H.

    2009-01-01

    In spite of numerous habitat restoration programs in fresh waters with an aggregate annual funding of millions of dollars, many populations of Pacific salmon remain significantly imperiled. Habitat restoration strategies that address limited environmental attributes and partial salmon life-history requirements or approaches that attempt to force aquatic habitat to conform to idealized but ecologically unsustainable conditions may partly explain this lack of response. Natural watershed processes generate highly variable environmental conditions and population responses, i.e., multiple life histories, that are often not considered in restoration. Examples from several locations underscore the importance of natural variability to the resilience of Pacific salmon. The implication is that habitat restoration efforts will be more likely to foster salmon resilience if they consider processes that generate and maintain natural variability in fresh water. We identify three specific criteria for management based on natural variability: the capacity of aquatic habitat to recover from disturbance, a range of habitats distributed across stream networks through time sufficient to fulfill the requirements of diverse salmon life histories, and ecological connectivity. In light of these considerations, we discuss current threats to habitat resilience and describe how regulatory and restoration approaches can be modified to better incorporate natural variability. ?? 2009 by the author(s).

  4. Are inland wolf-ungulate systems influenced by marine subsidies of Pacific salmon?

    USGS Publications Warehouse

    Adams, L.G.; Farley, Sean D.; Stricker, C.A.; Demma, D.J.; Roffler, G.H.; Miller, D.C.; Rye, R.O.

    2010-01-01

    Wolves (Canis lupus) in North America are considered obligate predators of ungulates with other food resources playing little role in wolf population dynamics or wolf-prey relations. However, spawning Pacific salmon (Oncorhyncus spp.) are common throughout wolf range in northwestern North America and may provide a marine subsidy affecting inland wolf-ungulate food webs far from the coast. We conducted stable-isotope analyses for nitrogen and carbon to evaluate the contribution of salmon to diets of wolves in Denali National Park and Preserve, 1200 river-km from tidewater in interior Alaska, USA. We analyzed bone collagen from 73 wolves equipped with radio collars during 1986-2002 and evaluated estimates of salmon in their diets relative to the availability of salmon and ungulates within their home ranges. We compared wolf densities and ungulate : wolf ratios among regions with differing salmon and ungulate availability to assess subsidizing effects of salmon on these wolf-ungulate systems. Wolves in the northwestern flats of the study area had access to spawning salmon but low ungulate availability and consumed more salmon (17% ?? 7% [mean ?? SD]) than in upland regions, where ungulates were sixfold more abundant and wolves did or did not have salmon spawning areas within their home ranges (8% ?? 6% and 3% ?? 3%, respectively). Wolves were only 17% less abundant on the northwestern flats compared to the remainder of the study area, even though ungulate densities were 78% lower. We estimated that biomass from fall runs of chum (O. keta) and coho (O. kisutch) salmon on the northwestern flats was comparable to the ungulate biomass there, and the contribution of salmon to wolf diets was similar to estimates reported for coastal wolves in southeast Alaska. Given the ubiquitous consumption of salmon by wolves on the northwestern flats and the abundance of salmon there, we conclude that wolf numbers in this region were enhanced by the allochthonous subsidy provided by

  5. WILD SALMON RESTORATION IN THE PACIFIC NORTHWEST: FORECASTING THE TWENTY-FIRST CENTURY

    EPA Science Inventory

    Restoring wild salmon runs to the Pacific Northwest is technically challenging, politically nasty, and socially divisive. Past restoration efforst have been largely unsuccessful. Society's failure to reverse the continuing decline of wild salmon has the characteristics of a pol...

  6. Evidence for competitive dominance of Pink salmon (Oncorhynchus gorbuscha) over other Salmonids in the North Pacific Ocean

    USGS Publications Warehouse

    Ruggerone, G.T.; Nielsen, J.L.

    2004-01-01

    Relatively little is known about fish species interactions in offshore areas of the world's oceans because adequate experimental controls are typically unavailable in such vast areas. However, pink salmon (Oncorhynchus gorbuscha) are numerous and have an alternating-year pattern of abundance that provides a natural experimental control to test for interspecific competition in the North Pacific Ocean and Bering Sea. Since a number of studies have recently examined pink salmon interactions with other salmon, we reviewed them in an effort to describe patterns of interaction over broad regions of the ocean. Research consistently indicated that pink salmon significantly altered prey abundance of other salmon species (e.g., zooplankton, squid), leading to altered diet, reduced total prey consumption and growth, delayed maturation, and reduced survival, depending on species and locale. Reduced survival was observed in chum salmon (O. keta) and Chinook salmon (O. tshawytscha) originating from Puget Sound and in Bristol Bay sockeye salmon (O. nerka). Growth of pink salmon was not measurably affected by other salmon species, but their growth was sometimes inversely related to their own abundance. In all marine studies, pink salmon affected other species through exploitation of prey resources rather than interference. Interspecific competition was observed in nearshore and offshore waters of the North Pacific Ocean and Bering Sea, and one study documented competition between species originating from different continents. Climate change had variable effects on competition. In the North Pacific Ocean, competition was observed before and after the ocean regime shift in 1977 that significantly altered abundances of many marine species, whereas a study in the Pacific Northwest reported a shift from predation- to competition-based mortality in response to the 1982/1983 El Nino. Key traits of pink salmon that influenced competition with other salmonids included great abundance, high

  7. Evaluations of alternative methods for monitoring and estimating responses of salmon productivity in the North Pacific to future climatic change and other processes: A simulation study

    EPA Science Inventory

    Estimation of the relative influence of climate change, compared to other human activities, on dynamics of Pacific salmon (Oncorhynchus spp.) populations can help management agencies take appropriate management actions. We used empirically based simulation modelling of 48 sockeye...

  8. Magnification and toxicity of PCBs, PCDDs, and PCDFs in upriver-migrating Pacific salmon.

    PubMed

    Debruyn, Adrian M H; Ikonomou, Michael G; Gobas, Frank A P C

    2004-12-01

    The depletion of lipids associated with pre-spawning migration of Pacific salmon has the potential to magnify concentrations of hydrophobic organic contaminants (HOCs), which elevates risk of toxic effects. We present data from a field study of sockeye salmon (Oncorhynchus nerka) migrating to spawn in Great Central Lake, BC, which demonstrate that pre-spawning migration causes a magnification of PCB, PCDD, and PCDF concentrations in female gonads (1.9-2.5-fold), female soma (3.4-5.6-fold), and male soma (5.6-9.7-fold). We further develop a model of prespawning migration chemical magnification for sockeye salmon stocks as a function of migration distance. This model is shown to be consistent with available empirical data on pre-spawning magnification and predicts magnification factors ranging between 1.4 and 7.9 in gonad and between 1.6 and 10.4 in soma in seven Pacific salmon stocks in British Columbia. Post-migration (prespawning) toxic equivalent dioxin concentrations in roe were measured to be approximately 3 pg/g lipid in salmon from the Great Central Lake sockeye stock and estimated to range between 1.5 pg/g lipid for the shortest-migrating stocks and 7 pg/g lipid for the longest-migrating stocks. Concentrations in certain stocks approach or exceed the concentration of 3 pg/g lipid associated with 30% egg mortality in Oncorhynchus mykiss. This indicates the potential for population-level effects of current contaminant levels. It also suggests that historic contaminant concentrations, which were greater than current concentrations, may have contributed significantly to the decline of certain Pacific salmon stocks in British Columbia.

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

    PubMed

    Swain, Noel R; Reynolds, John D

    2015-01-01

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

  10. Effects of Salmon-Derived Nutrients and Habitat Characteristics on Population Densities of Stream-Resident Sculpins

    PubMed Central

    Swain, Noel R.; Reynolds, John D.

    2015-01-01

    Movement of nutrients across ecosystem boundaries can have important effects on food webs and population dynamics. An example from the North Pacific Rim is the connection between productive marine ecosystems and freshwaters driven by annual spawning migrations of Pacific salmon (Oncorhynchus spp). While a growing body of research has highlighted the importance of both pulsed nutrient subsidies and disturbance by spawning salmon, their effects on population densities of vertebrate consumers have rarely been tested, especially across streams spanning a wide range of natural variation in salmon densities and habitat characteristics. We studied resident freshwater prickly (Cottus asper), and coastrange sculpins (C. aleuticus) in coastal salmon spawning streams to test whether their population densities are affected by spawning densities of pink and chum salmon (O. gorbuscha and O. keta), as well as habitat characteristics. Coastrange sculpins occurred in the highest densities in streams with high densities of spawning pink and chum salmon. They also were more dense in streams with high pH, large watersheds, less area covered by pools, and lower gradients. In contrast, prickly sculpin densities were higher in streams with more large wood and pools, and less canopy cover, but their densities were not correlated with salmon. These results for coastrange sculpins provide evidence of a numerical population response by freshwater fish to increased availability of salmon subsidies in streams. These results demonstrate complex and context-dependent relationships between spawning Pacific salmon and coastal ecosystems and can inform an ecosystem-based approach to their management and conservation. PMID:26030145

  11. Compendium of Low-Cost Pacific Salmon and Steelhead Trout Production Facilities and Practices in the Pacific Northwest.

    SciTech Connect

    Senn, Harry G.

    1984-09-01

    The purpose was to research low capital cost salmon and steelhead trout production facilities and identify those that conform with management goals for the Columbia Basin. The species considered were chinook salmon (Oncorhynchus tshawytscha), coho salmon (O. kisutch), sockeye salmon (O. nerka), and steelhead trout (Salmo gairdneri). This report provides a comprehensive listing of the facilities, techniques, and equipment used in artificial production in the Pacific Northwest. (ACR)

  12. 77 FR 19605 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Salmon

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-04-02

    ... Economic Zone Off Alaska; Pacific Salmon AGENCY: National Marine Fisheries Service (NMFS), National Oceanic...) submitted Amendments 10, 11, and 12 to the Fishery Management Plan for the Salmon Fisheries in the EEZ off... comprehensively revise and update the FMP to reflect the Council's salmon management policy and Federal...

  13. The Lummi Indians and the Canadian/American Pacific Salmon Treaty.

    ERIC Educational Resources Information Center

    Boxberger, Daniel L.

    1988-01-01

    Explores the probable impact of the 1985 international Pacific Salmon Treaty on the Lummi tribe's catch of Fraser River salmon and economic well-being. Discusses the 1974 Boldt Decision, which allocated half of Washington State's salmon catch to treaty tribes, and contradictions in the federal government's conception of international treaties. (SV)

  14. REALITY, DELUSIONS, AND OTHER ASSORTED TRUTHS: THE FUTURE OF SALMON IN THE PACIFIC NORTHWEST

    EPA Science Inventory

    Are professional fisheries scientists collectively guilty of encouraging delusions about the possibilities for restoring wild salmon to the Pacific Northwest? Do they perpetuate the fantasy that the Pacific Northwest will (or could, absent pervasive life-style changes) support w...

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

    SciTech Connect

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

    2002-08-01

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

  16. Clock polymorphism in Pacific salmon: evidence for variable selection along a latitudinal gradient.

    PubMed

    O'Malley, Kathleen G; Ford, Michael J; Hard, Jeffrey J

    2010-12-22

    Seasonal timing of life-history events is often under strong natural selection. The Clock gene is a central component of an endogenous circadian clock that senses changes in photoperiod (day length) and mediates seasonal behaviours. Among Pacific salmonids (Oncorhynchus spp.), seasonal timing of migration and breeding is influenced by photoperiod. To expand a study of 42 North American Chinook salmon (Oncorhynchus tshawytscha) populations, we tested whether duplicated Clock genes contribute to population differences in reproductive timing. Specifically, we examined geographical variation along a similar latitudinal gradient in the polyglutamine domain (PolyQ) of OtsClock1a and OtsClock1b among 53 populations of three species: chum (Oncorhynchus keta), coho (Oncorhynchus kisutch) and pink salmon (Oncorhynchus gorbuscha). We found evidence for variable selection on OtsClock1b that corresponds to latitudinal variation in reproductive timing among these species. We evaluated the contribution of day length and a freshwater migration index to OtsClock1b PolyQ domain variation using regression trees and found that day length at spawning explains much of the variation in OtsClock1b allele frequency among chum and Chinook, but not coho and pink salmon populations. Our findings suggest that OtsClock1b mediates seasonal adaptation and influences geographical variation in reproductive timing in some of these highly migratory species.

  17. Transcriptomic responses to high water temperature in two species of Pacific salmon

    PubMed Central

    Jeffries, Ken M; Hinch, Scott G; Sierocinski, Thomas; Pavlidis, Paul; Miller, Kristi M

    2014-01-01

    Characterizing the cellular stress response (CSR) of species at ecologically relevant temperatures is useful for determining whether populations and species can successfully respond to current climatic extremes and future warming. In this study, populations of wild-caught adult pink (Oncorhynchus gorbuscha) and sockeye (Oncorhynchus nerka) salmon from the Fraser River, British Columbia, Canada, were experimentally treated to ecologically relevant ‘cool’ or ‘warm’ water temperatures to uncover common transcriptomic responses to elevated water temperature in non-lethally sampled gill tissue. We detected the differential expression of 49 microarray features (29 unique annotated genes and one gene with unknown function) associated with protein folding, protein synthesis, metabolism, oxidative stress and ion transport that were common between populations and species of Pacific salmon held at 19°C compared with fish held at a cooler temperature (13 or 14°C). There was higher mortality in fish held at 19°C, which suggests a possible relationship between a temperature-induced CSR and mortality in these species. Our results suggest that frequently encountered water temperatures ≥19°C, which are capable of inducing a common CSR across species and populations, may increase risk of upstream spawning migration failure for pink and sockeye salmon. PMID:24567748

  18. Transcriptomic responses to high water temperature in two species of Pacific salmon.

    PubMed

    Jeffries, Ken M; Hinch, Scott G; Sierocinski, Thomas; Pavlidis, Paul; Miller, Kristi M

    2014-02-01

    Characterizing the cellular stress response (CSR) of species at ecologically relevant temperatures is useful for determining whether populations and species can successfully respond to current climatic extremes and future warming. In this study, populations of wild-caught adult pink (Oncorhynchus gorbuscha) and sockeye (Oncorhynchus nerka) salmon from the Fraser River, British Columbia, Canada, were experimentally treated to ecologically relevant 'cool' or 'warm' water temperatures to uncover common transcriptomic responses to elevated water temperature in non-lethally sampled gill tissue. We detected the differential expression of 49 microarray features (29 unique annotated genes and one gene with unknown function) associated with protein folding, protein synthesis, metabolism, oxidative stress and ion transport that were common between populations and species of Pacific salmon held at 19°C compared with fish held at a cooler temperature (13 or 14°C). There was higher mortality in fish held at 19°C, which suggests a possible relationship between a temperature-induced CSR and mortality in these species. Our results suggest that frequently encountered water temperatures ≥19°C, which are capable of inducing a common CSR across species and populations, may increase risk of upstream spawning migration failure for pink and sockeye salmon. PMID:24567748

  19. Trends in spawning populations of Pacific anadromous salmonids

    USGS Publications Warehouse

    Konkel, G.W.; McIntyre, J.D.

    1987-01-01

    Annual escapement records for 1968-1984 for five species of Pacific salmon-chinook (Oncorhynchus tshawytscha), coho (O. kisutch), sockeye (O. nerka), pink (O. gorbuscha), and chum (O. keta)—and steelhead (Salmo gairdneri) were obtained from published and unpublished sources and organized in a computer database. More than 25,500 escapement records were obtained for more than 1,100 locations throughout Alaska, Washington, Idaho, Oregon, and California. Escapement trends for naturally reproducing populations for which data were available for at least 7 years from 1968 to 1984 and at least 4 years from 1975 to 1984 were analyzed by linear regression. Significant trends were observed in about 30% of the 886 populations examined. Trends were summarized by species for three geographic regions in Alaska and four in the Pacific Northwest (including California). For chinook, sockeye, and pink salmon, trends were predominantly increasing in the Alaska regions and either lacking or predominantly decreasing in most of the Pacific Northwest regions; for coho and chum salmon, trends were predominantly decreasing in one or more Alaska regions as well as in most of the Pacific Northwest regions. For steelhead, too few populations were examined to enable us to characterize trends throughout their range. Among the 657 salmonid populations excluded from the trend analysis because the data sets were incomplete, 13 (of which 2 were in Alaska) declined to zero during the period of analysis. For coho, sockeye, pink, and chum salmon and steelhead, major data gaps were revealed by a comparison of the geographic distribution of escapement records with the spawning distribution of the species. For chinook salmon, escapement records were more geographically representative of the spawning distribution.

  20. THE PACIFIC NORTHWEST IN 2100: AN ALTERNATIVE FUTURES PERSPECTIVE ON SALMON RECOVERY

    EPA Science Inventory

    The primary goal of the Salmon 2100 Project is to identify practical options that have a high probability of maintaining biologically significant, sustainable populations of wild salmon in California, Oregon, Washington, Idaho, and southern British Columbia. The Project does not ...

  1. Contaminant exposure in outmigrant juvenile salmon from Pacific Northwest estuaries of the United States.

    PubMed

    Johnson, Lyndal L; Ylitalo, Gina M; Arkoosh, Mary R; Kagley, Anna N; Stafford, Coral; Bolton, Jennie L; Buzitis, Jon; Anulacion, Bernadita F; Collier, Tracy K

    2007-01-01

    To better understand the dynamics of contaminant uptake in outmigrant juvenile salmon in the Pacific Northwest, concentrations of polychlorinated biphenyls (PCBs), DDTs, polycylic aromatic hydrocarbons (PAHs) and organochlorine pesticides were measured in tissues and prey of juvenile chinook and coho salmon from several estuaries and hatcheries in the US Pacific Northwest. PCBs, DDTs, and PAHs were found in tissues (whole bodies or bile) and stomach contents of chinook and coho salmon sampled from all estuaries, as well as in chinook salmon from hatcheries. Organochlorine pesticides were detected less frequently. Of the two species sampled, chinook salmon had the highest whole body contaminant concentrations, typically 2--5 times higher than coho salmon from the same sites. In comparison to estuarine chinook salmon, body burdens of PCBs and DDTs in hatchery chinook were relatively high, in part because of the high lipid content of the hatchery fish. Concentrations of PCBs were highest in chinook salmon from the Duwamish Estuary, the Columbia River and Yaquina Bay, exceeding the NOAA Fisheries' estimated threshold for adverse health effects of 2400 ng/g lipid. Concentrations of DDTs were especially high in juvenile chinook salmon from the Columbia River and Nisqually Estuary; concentrations of PAH metabolites in bile were highest in chinook salmon from the Duwamish Estuary and Grays Harbor. Juvenile chinook salmon are likely absorbing some contaminants during estuarine residence through their prey, as PCBs, PAHs, and DDTs were consistently present in stomach contents, at concentrations significantly correlated with contaminant body burdens in fish from the same sites.

  2. Global Assessment of Extinction Risk to Populations of Sockeye Salmon Oncorhynchus nerka

    PubMed Central

    Rand, Peter S.; Goslin, Matthew; Gross, Mart R.; Irvine, James R.; Augerot, Xanthippe; McHugh, Peter A.; Bugaev, Victor F.

    2012-01-01

    Background Concern about the decline of wild salmon has attracted the attention of the International Union for the Conservation of Nature (IUCN). The IUCN applies quantitative criteria to assess risk of extinction and publishes its results on the Red List of Threatened Species. However, the focus is on the species level and thus may fail to show the risk to populations. The IUCN has adapted their criteria to apply to populations but there exist few examples of this type of assessment. We assessed the status of sockeye salmon Oncorhynchus nerka as a model for application of the IUCN population-level assessments and to provide the first global assessment of the status of an anadromous Pacific salmon. Methods/Principal Findings We found from demographic data that the sockeye salmon species is not presently at risk of extinction. We identified 98 independent populations with varying levels of risk within the species' range. Of these, 5 (5%) are already extinct. We analyzed the risk for 62 out of 93 extant populations (67%) and found that 17 of these (27%) are at risk of extinction. The greatest number and concentration of extinct and threatened populations is in the southern part of the North American range, primarily due to overfishing, freshwater habitat loss, dams, hatcheries, and changing ocean conditions. Conclusions/Significance Although sockeye salmon are not at risk at the species-level, about one-third of the populations that we analyzed are at risk or already extinct. Without an understanding of risk to biodiversity at the level of populations, the biodiversity loss in salmon would be greatly underrepresented on the Red List. We urge government, conservation organizations, scientists and the public to recognize this limitation of the Red List. We also urge recognition that about one-third of sockeye salmon global population diversity is at risk of extinction or already extinct. PMID:22511930

  3. Evaluation of the Contribution of Fall Chinook Salmon Reared at Columbia River Hatcheries to the Pacific Salmon Fisheries, Appendix, 1989 Final Report.

    SciTech Connect

    Vreeland, Robert R.

    1989-10-01

    This document contains 43 appendices for the Evaluation of the Contribution of Fall Chinook Salmon Reared at Columbia River Hatcheries to the Pacific Salmon Fisheries'' report. This study was initiated to determine the distribution, contribution, and value of artificially propagated fall Chinook Salmon from the Columbia River.

  4. RESTORING WILD SALMON TO THE PACIFIC NORTHWEST: FRAMING THE RISK QUESTION

    EPA Science Inventory

    In the Pacific Northwest of the United States, it is urgent to assess accurately the various options proposed to restore wild salmon. For the past 125 years, a variety of analytic approaches have been employed to assess the ecological consequences of salmon management options. ...

  5. [Single-nucleotide polymorphism in populations of sockeye salmon Oncorhynchus nerka from Kamchatka Peninsula].

    PubMed

    Khrustaleva, A M; Gritsenko, O F; Klovach, N V

    2013-11-01

    The genetic polymorphism of 45 single-nucleotide polymorphism loci was examined in the four largest wild populations of sockeye salmon Oncorhynchusnerka from drainages of the Asian coast of the Pacific Ocean (Eastern and Western Kamchatka). It was demonstrated that sockeye salmon from the Palana River were considerably different from all other populations examined. The most probable explanation of the observed differences is the suggestion on possible demographic events in the history of this population associated with the decrease in its effective number. To study the origin, colonization patterns, and evolution of Asian sockeye salmon, as well as to resolve some of the applied tasks, like population assignment and genetic identification, a differentiation approach to SNP-marker selection was suggested. Adaptively important loci that evolve under the pressure of balancing (stabilizing) selection were identified, thanks to which the number of loci that provide the baseline classification error rates in the population assignment tests was reduced to 30. It was demonstrated that SNPs located in the MHC2 and GPH genes were affected by diversifying selection. Procedures for selecting single-nucleotide polymorphisms for phylogenetic studies of Asian sockeye salmon were suggested. Using principal-component analysis, 17 loci that adequately reproduce genetic differentiation within arid among the regions of the origin of Kamchatka sockeye salmon, were selected. PMID:25470934

  6. [Single-nucleotide polymorphism in populations of sockeye salmon Oncorhynchus nerka from Kamchatka Peninsula].

    PubMed

    2013-11-01

    The genetic polymorphism of 45 single-nucleotide polymorphism loci was examined in the four largest wild populations of sockeye salmon Oncorhynchusnerka from drainages of the Asian coast of the Pacific Ocean (Eastern and Western Kamchatka). It was demonstrated that sockeye salmon from the Palana River were considerably different from all other populations examined. The most probable explanation of the observed differences is the suggestion on possible demographic events in the history of this population associated with the decrease in its effective number. To study the origin, colonization patterns, and evolution of Asian sockeye salmon, as well as to resolve some of the applied tasks, like population assignment and genetic identification, a differentiation approach to SNP-marker selection was suggested. Adaptively important loci that evolve under the pressure of balancing (stabilizing) selection were identified, thanks to which the number of loci that provide the baseline classification error rates in the population assignment tests was reduced to 30. It was demonstrated that SNPs located in the MHC2 and GPH genes were affected by diversifying selection. Procedures for selecting single-nucleotide polymorphisms for phylogenetic studies of Asian sockeye salmon were suggested. Using principal-component analysis, 17 loci that adequately reproduce genetic differentiation within arid among the regions of the origin of Kamchatka sockeye salmon, were selected. PMID:25508561

  7. Long-term Records of Pacific Salmon Abundance From Sediment Core Analysis: Relationships to Past Climatic Change, and Implications for the Future

    NASA Astrophysics Data System (ADS)

    Finney, B.

    2002-12-01

    The response of Pacific salmon to future climatic change is uncertain, but will have large impacts on the economy, culture and ecology of the North Pacific Rim. Relationships between sockeye salmon populations and climatic change can be determined by analyzing sediment cores from lakes where sockeye return to spawn. Sockeye salmon return to their natal lake system to spawn and subsequently die following 2 - 3 years of feeding in the North Pacific Ocean. Sockeye salmon abundance can be reconstructed from stable nitrogen isotope analysis of lake sediment cores as returning sockeye transport significant quantities of N, relatively enriched in N-15, from the ocean to freshwater systems. Temporal changes in the input of salmon-derived N, and hence salmon abundance, can be quantified through downcore analysis of N isotopes. Reconstructions of sockeye salmon abundance from lakes in several regions of Alaska show similar temporal patterns, with variability occurring on decadal to millennial timescales. Over the past 2000 years, shifts in sockeye salmon abundance far exceed the historical decadal-scale variability. A decline occurred from about 100 BC - 800 AD, but salmon were consistently more abundant 1200 - 1900 AD. Declines since 1900 AD coincide with the period of extensive commercial fishing. Correspondence between these records and paleoclimatic data suggest that changes in salmon abundance are related to large scale climatic changes over the North Pacific. For example, the increase in salmon abundance c.a. 1200 AD corresponds to a period of glacial advance in southern Alaska, and a shift to drier conditions in western North America. Although the regionally coherent patterns in reconstructed salmon abundance are consistent with the hypothesis that climate is an important driver, the relationships do not always follow patterns observed in the 20th century. A main feature of recorded climate variability in this region is the alternation between multi-decade periods of

  8. Transcriptomic responses to emamectin benzoate in Pacific and Atlantic Canada salmon lice Lepeophtheirus salmonis with differing levels of drug resistance

    PubMed Central

    Sutherland, Ben J G; Poley, Jordan D; Igboeli, Okechukwu O; Jantzen, Johanna R; Fast, Mark D; Koop, Ben F; Jones, Simon R M

    2015-01-01

    Salmon lice Lepeophtheirus salmonis are an ecologically and economically important parasite of wild and farmed salmon. In Scotland, Norway, and Eastern Canada, L. salmonis have developed resistance to emamectin benzoate (EMB), one of the few parasiticides available for salmon lice. Drug resistance mechanisms can be complex, potentially differing among populations and involving multiple genes with additive effects (i.e., polygenic resistance). Indicators of resistance development may enable early detection and countermeasures to avoid the spread of resistance. Here, we collect sensitive Pacific L. salmonis and sensitive and resistant Atlantic L. salmonis from salmon farms, propagate in laboratory (F1), expose to EMB in bioassays, and evaluate either baseline (Atlantic only) or induced transcriptomic differences between populations. In all populations, induced responses were minor and a cellular stress response was not identified. Pacific lice did not upregulate any genes in response to EMB, but downregulated degradative enzymes and transport proteins at 50 ppb EMB. Baseline differences between sensitive and now resistant Atlantic lice were much greater than responses to exposures. All resistant lice overexpressed degradative enzymes, and resistant males, the most resistant group, overexpressed collagenases to the greatest extent. These results indicate an accumulation of baseline expression differences related to resistance. PMID:25685190

  9. Transcriptomic responses to emamectin benzoate in Pacific and Atlantic Canada salmon lice Lepeophtheirus salmonis with differing levels of drug resistance.

    PubMed

    Sutherland, Ben J G; Poley, Jordan D; Igboeli, Okechukwu O; Jantzen, Johanna R; Fast, Mark D; Koop, Ben F; Jones, Simon R M

    2015-02-01

    Salmon lice Lepeophtheirus salmonis are an ecologically and economically important parasite of wild and farmed salmon. In Scotland, Norway, and Eastern Canada, L. salmonis have developed resistance to emamectin benzoate (EMB), one of the few parasiticides available for salmon lice. Drug resistance mechanisms can be complex, potentially differing among populations and involving multiple genes with additive effects (i.e., polygenic resistance). Indicators of resistance development may enable early detection and countermeasures to avoid the spread of resistance. Here, we collect sensitive Pacific L. salmonis and sensitive and resistant Atlantic L. salmonis from salmon farms, propagate in laboratory (F1), expose to EMB in bioassays, and evaluate either baseline (Atlantic only) or induced transcriptomic differences between populations. In all populations, induced responses were minor and a cellular stress response was not identified. Pacific lice did not upregulate any genes in response to EMB, but downregulated degradative enzymes and transport proteins at 50 ppb EMB. Baseline differences between sensitive and now resistant Atlantic lice were much greater than responses to exposures. All resistant lice overexpressed degradative enzymes, and resistant males, the most resistant group, overexpressed collagenases to the greatest extent. These results indicate an accumulation of baseline expression differences related to resistance.

  10. Non-indigenous brook trout and the demise of Pacific salmon: a forgotten threat?

    PubMed Central

    Levin, Phillip S; Achord, Stephen; Feist, Blake E; Zabel, Richard W

    2002-01-01

    Non-indigenous species may be the most severe environmental threat the world now faces. Fishes, in particular, have been intentionally introduced worldwide and have commonly caused the local extinction of native fish. Despite their importance, the impact of introduced fishes on threatened populations of Pacific salmon has never been systemically examined. Here, we take advantage of several unique datasets from the Columbia River Basin to address the impact of non-indigenous brook trout, Salvelinus fontinalis, on threatened spring/summer-run chinook salmon, Oncorhynchus tshawytscha. More than 41 000 juvenile chinook were individually marked, and their survival in streams without brook trout was nearly double the survival in streams with brook trout. Furthermore, when brook trout were absent, habitat quality was positively associated with chinook survival, but when brook trout were present no relationship between chinook survival and habitat quality was evident. The difference in juvenile chinook survival between sites with, and without, brook trout would increase population growth rate (lambda) by ca. 2.5%. This increase in lambda would be sufficient to reverse the negative population growth observed in many chinook populations. Because many of the populations we investigated occur in wilderness areas, their habitat has been considered pristine; however, our results emphasize that non-indigenous species are present and may have a dramatic impact, even in remote regions that otherwise appear pristine. PMID:12204126

  11. Evaluating tributary restoration potential for Pacific salmon recovery.

    PubMed

    Budy, Phaedra; Schaller, Howard

    2007-06-01

    Although habitat restoration can play a key role in the conservation of imperiled species, for animals that demonstrate long migrations and complex life histories, reliance on physical restoration of isolated habitat patches comes with considerable uncertainty. Nevertheless, within freshwater ecosystems, stream restoration has become a major conservation focus, with millions of dollars spent annually on efforts aimed at recovering degraded habitat and imperiled riverine species. Within this context, we addressed fundamental uncertainties of the focus on tributary restoration for recovery of salmon: (1) Is there potential for improving habitat in tributaries? (2) What magnitude of early survival improvement can be expected based on stream restoration? and (3) Will incremental increases in early survival be sufficient to ensure viability overall? We combined simple mechanistic habitat models, population viability measures, and categorical filters to quantify "restoration potential," expressed as increased total life-cycle survival in response to restored tributary condition, across 32 populations composing five major population groups (MPG). A wide gap remains between how much survival improvement is needed vs. what is likely to occur; restoration potential meets the necessary minimum increase needed for only four populations within one MPG. The remaining populations (84%, 4 MPG) still fall far below the survival increase needed for future viability. In addition, across all populations and groups, a 171% increase (on average) in total life-cycle survival is needed; only approximately 106% appears possible. A recovery strategy for these salmon that relies largely on tributary restoration to mitigate for known mortality imposed at other life stages (e.g., migration through hydropower dams) is risky with a low probability of success. We demonstrate an approach for completing an a priori evaluation of restoration potential linked to population viability, such that

  12. Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (Pacific Northwest): Pink salmon

    SciTech Connect

    Bonar, S.A.; Pauley, G.B.; Thomas, G.L.

    1989-01-01

    Species profiles are literature summaries of the taxonomy, morphology, range, life history, and environmental requirements of coastal aquatic species. They are designed to assist in environmental impact assessment. The pink salmon, often called humpback salmon or humpy, is easily identified by its extremely small scales (150 to 205) on the lateral line. They are the most abundant of the Pacific salmon species and spawn in North American and Asian streams bordering the Pacific and Arctic Oceans. They have a very simple two-year life cycle, which is so invariable that fish running in odd-numbered years are isolated from fish running in even-numbered years so that no gene flow occurs between them. Adults spawn in the fall and the young fry emerge in the spring. The pink salmon is less desirable in commercial and sport catches than most other salmon because of its small size and its soft pale flesh. The Puget Sound region of Washington State is the southern geographic limit of streams supporting major pink salmon runs in the eastern North Pacific. Pink salmon runs are presently only in odd-numbered years in this region. Optimum water temperatures for spawning range from 7.2 to 12.8/degree/C. Productive pink salmon streams have less than 5.0% by volume of fine sediments (less than or equal to0.8 mm). 87 refs., 5 figs., 1 tab.

  13. Influence of breeding habitat on bear predation and age at maturity and sexual dimorphism of sockeye salmon populations

    USGS Publications Warehouse

    Quinn, Thomas P; Wetzel, Lisa A.; Bishop, Susan; Overberg, Kristi; Rogers, Donald E.

    2001-01-01

    Age structure and morphology differ among Pacific salmon (Oncorhynchus spp.) populations. Sexual selection and reproductive capacity (fecundity and egg size) generally favor large (old), deep-bodied fish. We hypothesized that natural selection from physical access to spawning grounds and size-biased predation by bears, Ursus spp., opposes such large, deep-bodied salmon. Accordingly, size and shape of salmon should vary predictably among spawning habitats. We tested this hypothesis by measuring the age composition and body depth of sockeye salmon, Oncorhynchus nerka, and the intensity of predation in a range of breeding habitats in southwestern Alaska. Stream width was positively correlated with age at maturity and negatively correlated with predation level. However, salmon spawning on lake beaches were not consistently old, indicating that different factors affect age in riverine- and beach-spawning populations. Body depths of male and female salmon were positively correlated with water depth across all sites, as predicted. However, the mouths of some streams were so shallow that they might select against large or deep-bodied salmon, even in the absence of bear predation. Taken together, the results indicated that habitat has direct and indirect effects (via predation) on life history and morphology of mature salmon.

  14. Genetic analysis of paramyxovirus isolates from pacific salmon reveals two independently co-circulating lineages

    USGS Publications Warehouse

    Batts, W.N.; Falk, K.; Winton, J.R.

    2008-01-01

    Viruses with the morphological and biochemical characteristics of the family Paramyxoviridae (paramyxoviruses) have been isolated from adult salmon returning to rivers along the Pacific coast of North America since 1982. These Pacific salmon paramyxoviruses (PSPV), which have mainly been isolated from Chinook salmon Oncorhynchus tshawytscha, grow slowly in established fish cell lines and have not been associated with disease. Genetic analysis of a 505-base-pair region of the polymerase gene from 47 PsPV isolates produced 17 nucleotide sequence types that could be grouped into two major sublineages, designated A and B. The two independently co-circulating sublineages differed by 12.1-13.9% at the nucleotide level but by only 1.2% at the amino acid level. Isolates of PSPV from adult Pacific salmon returning to rivers from Alaska to California over a 25-year period showed little evidence of geographic or temporal grouping. Phylogenetic analyses revealed that these paramyxoviruses of Pacific salmon were most closely related to the Atlantic salmon paramyxovirus (ASPV) from Norway, having a maximum nucleotide diversity of 26.1 % and an amino acid diversity of 19.0%. When compared with homologous sequences of other paramyxoviruses, PSPV and ASPV were sufficiently distinct to suggest that they are not clearly members of any of the established genera in the family Paramyxoviridae. in the course of this study, a polymerase chain reaction assay was developed that can be used for confirmatory identification of PSPV. ?? Copyright by the American Fisheries Society 2008.

  15. EST and mitochondrial DNA sequences support a distinct Pacific form of salmon louse, Lepeophtheirus salmonis.

    PubMed

    Yazawa, Ryosuke; Yasuike, Motoshige; Leong, Jong; von Schalburg, Kristian R; Cooper, Glenn A; Beetz-Sargent, Marianne; Robb, Adrienne; Davidson, William S; Jones, Simon R M; Koop, Ben F

    2008-01-01

    Nuclear deoxyribonucleic acid sequences from approximately 15,000 salmon louse expressed sequence tags (ESTs), the complete mitochondrial genome (16,148bp) of salmon louse, and 16S ribosomal ribonucleic acid (rRNA) and cytochrome oxidase subunit I (COI) genes from 68 salmon lice collected from Japan, Alaska, and western Canada support a Pacific lineage of Lepeophtheirus salmonis that is distinct from that occurring in the Atlantic Ocean. On average, nuclear genes are 3.2% different, the complete mitochondrial genome is 7.1% different, and 16S rRNA and COI genes are 4.2% and 6.1% different, respectively. Reduced genetic diversity within the Pacific form of L. salmonis is consistent with an introduction into the Pacific from the Atlantic Ocean. The level of divergence is consistent with the hypothesis that the Pacific form of L. salmonis coevolved with Pacific salmon (Onchorhynchus spp.) and the Atlantic form coevolved with Atlantic salmonids (Salmo spp.) independently for the last 2.5-11 million years. The level of genetic divergence coincides with the opportunity for migration of fish between the Atlantic and Pacific Ocean basins via the Arctic Ocean with the opening of the Bering Strait, approximately 5 million years ago. The genetic differences may help explain apparent differences in pathogenicity and environmental sensitivity documented for the Atlantic and Pacific forms of L. salmonis. PMID:18574633

  16. An Assessment of the Status of Captive Broodstock Technology of Pacific Salmon, 1995 Final Report.

    SciTech Connect

    Flagg, Thomas A.; Mahnaken, Conrad V.W.; Hard, Jeffrey J.

    1995-06-01

    This report provides guidance for the refinement and use of captive broodstock technology for Pacific salmon (Oncorhynchus spp.) by bringing together information on the husbandry techniques, genetic risks, physiology, nutrition, and pathology affecting captive broodstocks. Captive broodstock rearing of Pacific salmon is an evolving technology, as yet without well defined standards. At present, we regard captive rearing of Pacific salmon as problematic: high mortality rates and low egg viability were common in the programs we reviewed for this report. One of the most important elements in fish husbandry is the culture environment itself. Many captive broodstock programs for Pacific salmon have reared fish from smolt-to-adult in seawater net-pens, and most have shown success in providing gametes for recovery efforts. However, some programs have lost entire brood years to diseases that transmitted rapidly in this medium. Current programs for endangered species of Pacific salmon rear most fish full-term to maturity in fresh well-water, since ground water is low in pathogens and thus helps ensure survival to adulthood. Our review suggested that captive rearing of fish in either freshwater, well-water, or filtered and sterilized seawater supplied to land-based tanks should produce higher survival than culture in seawater net-pens.

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

    SciTech Connect

    United States. Bonneville Power Administration.

    1994-06-01

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

  18. IBSEM: An Individual-Based Atlantic Salmon Population Model.

    PubMed

    Castellani, Marco; Heino, Mikko; Gilbey, John; Araki, Hitoshi; Svåsand, Terje; Glover, Kevin A

    2015-01-01

    Ecology and genetics can influence the fate of individuals and populations in multiple ways. However, to date, few studies consider them when modelling the evolutionary trajectory of populations faced with admixture with non-local populations. For the Atlantic salmon, a model incorporating these elements is urgently needed because many populations are challenged with gene-flow from non-local and domesticated conspecifics. We developed an Individual-Based Salmon Eco-genetic Model (IBSEM) to simulate the demographic and population genetic change of an Atlantic salmon population through its entire life-cycle. Processes such as growth, mortality, and maturation are simulated through stochastic procedures, which take into account environmental variables as well as the genotype of the individuals. IBSEM is based upon detailed empirical data from salmon biology, and parameterized to reproduce the environmental conditions and the characteristics of a wild population inhabiting a Norwegian river. Simulations demonstrated that the model consistently and reliably reproduces the characteristics of the population. Moreover, in absence of farmed escapees, the modelled populations reach an evolutionary equilibrium that is similar to our definition of a 'wild' genotype. We assessed the sensitivity of the model in the face of assumptions made on the fitness differences between farm and wild salmon, and evaluated the role of straying as a buffering mechanism against the intrusion of farm genes into wild populations. These results demonstrate that IBSEM is able to capture the evolutionary forces shaping the life history of wild salmon and is therefore able to model the response of populations under environmental and genetic stressors. PMID:26383256

  19. IBSEM: An Individual-Based Atlantic Salmon Population Model

    PubMed Central

    Castellani, Marco; Heino, Mikko; Gilbey, John; Araki, Hitoshi; Svåsand, Terje; Glover, Kevin A.

    2015-01-01

    Ecology and genetics can influence the fate of individuals and populations in multiple ways. However, to date, few studies consider them when modelling the evolutionary trajectory of populations faced with admixture with non-local populations. For the Atlantic salmon, a model incorporating these elements is urgently needed because many populations are challenged with gene-flow from non-local and domesticated conspecifics. We developed an Individual-Based Salmon Eco-genetic Model (IBSEM) to simulate the demographic and population genetic change of an Atlantic salmon population through its entire life-cycle. Processes such as growth, mortality, and maturation are simulated through stochastic procedures, which take into account environmental variables as well as the genotype of the individuals. IBSEM is based upon detailed empirical data from salmon biology, and parameterized to reproduce the environmental conditions and the characteristics of a wild population inhabiting a Norwegian river. Simulations demonstrated that the model consistently and reliably reproduces the characteristics of the population. Moreover, in absence of farmed escapees, the modelled populations reach an evolutionary equilibrium that is similar to our definition of a ‘wild’ genotype. We assessed the sensitivity of the model in the face of assumptions made on the fitness differences between farm and wild salmon, and evaluated the role of straying as a buffering mechanism against the intrusion of farm genes into wild populations. These results demonstrate that IBSEM is able to capture the evolutionary forces shaping the life history of wild salmon and is therefore able to model the response of populations under environmental and genetic stressors. PMID:26383256

  20. Early marine life history of juvenile Pacific salmon in two regions of Puget Sound

    USGS Publications Warehouse

    Duffy, E.J.; Beauchamp, D.A.; Buckley, R.M.

    2005-01-01

    Puget Sound could differentially represent either a simple migration corridor or an important rearing environment during the potentially critical early marine residence period for different species of Pacific salmon. Recent declines in various stocks of Puget Sound salmon could reflect degraded rearing conditions or changes in temporal-spatial utilization patterns by juvenile salmon in Puget Sound, and these patterns could vary between habitats and regions of Puget Sound in response to different environmental conditions or hatchery practices. In April-September 2001 and 2002, we evaluated spatial and temporal differences in distribution and size structure among juvenile chum, pink, coho, and chinook salmon at delta and nearshore habitats in a northern and southern region of Puget Sound, Washington. Water was consistently warmer (8-18.8??C) and less saline (0.0-27.7) in the northern (N) than in the southern region (S: 9.5-14.6??C, 13.0-30.4). Salinities were lower and water temperatures more variable in delta sites than exposed nearshore marine sites. Peak densities of juvenile salmon coincided at delta and nearshore sites within sampling regions but differed between regions. Nearshore densities were highest during April-June with pink and chum salmon generally preceding chinook and coho salmon, and peak catch rates of most species occurred in May. A second, late pulse of chinook salmon also occurred during July at northern sites. Juvenile chinook salmon were predominantly of hatchery origin in the southern region (98%), and of mixed origin in the northern region (44% marked hatchery fish) during 2002. The lengths of chinook and chum salmon in nearshore regions increased steadily through time, whereas pink and coho salmon varied inconsistently. Mean sizes of juvenile salmon were slightly but consistently smaller at delta than nearshore sites and at northern versus southern sites. Hatchery chinook salmon were slightly larger than their unmarked counterparts. Extended

  1. DETECTING PERSISTENT CHANGE IN THE HABITAT OF SALMON-BEARING STREAMS IN THE PACIFIC NORTHWEST

    EPA Science Inventory

    In the northwestern United States, there is considerable interest in the recovery of salmon populations listed as threatened or endangered under the Endangered Species Act. A critical component of any salmon recovery effort is the improvement of stream habitat that supports vario...

  2. THe Pacific Northwest in 2010: An alternative futures perspective on salmon recovery

    EPA Science Inventory

    The primary goal of the Salmon 2100 Project is to identify practical options that have a high probability of maintaining biologically significant, sustainable populations of wild salmon in California, Oregon, Washington, Idaho, and British Columbia. The Project does not support o...

  3. Eco-evolutionary dynamics: fluctuations in population growth rate reduce effective population size in chinook salmon.

    PubMed

    Waples, Robin S; Jensen, David W; McClure, Michelle

    2010-03-01

    We empirically assess the relationship between population growth rate (lambda, a parameter central to ecology) and effective population size (N(e), a key parameter in evolutionary biology). Recent theoretical and numerical studies indicate that in semelparous species with variable age at maturity (such as Pacific salmon, many monocarpic plants, and various other species), differences in mean reproductive success among individuals reproducing in different years leads to variation in lambda, and this in turn can reduce N(e). However, this phenomenon has received little empirical evaluation. We examined time series of abundance data for 56 populations of chinook salmon (Onchorhynchus tshawytscha) from the northwestern United States and compared N(e) (calculated from demographic data) with the total number of spawners each generation (NT). Important results include: (1) The mean multigenerational ratio N(e)/N(T) was 0.64 (median = 0.67), indicating that annual variation in lambda reduces effective population size in chinook salmon by an average of approximately 35%. These reductions are independent of, and in addition to, factors that reduce N(e) within individual cohorts (uneven sex ratio and greater-than-random variance in reproductive success). (2) The coefficient of variation of lambda was the most important factor associated with reductions in N(e), explaining up to two-thirds of the variance in N(e)/N(T). (3) Within individual generations, N(e) was lower when there was a negative correlation between annual N(i) and lambda, i.e., when relatively few breeders produced relatively high numbers of offspring. Our results thus highlight an important and little-studied eco-evolutionary trade-off: density-dependent compensation has generally favorable ecological consequences (promoting stability and long-term viability) but incurs an evolutionary cost (reducing N(e) because a few individuals make a disproportionate genetic contribution). (4) For chinook salmon, N(eH) (an

  4. Are there intergenerational and population-specific effects of oxidative stress in sockeye salmon (Oncorhynchus nerka)?

    PubMed

    Taylor, Jessica J; Wilson, Samantha M; Sopinka, Natalie M; Hinch, Scott G; Patterson, David A; Cooke, Steven J; Willmore, William G

    2015-06-01

    Intergenerational effects of stress have been reported in a wide range of taxa; however, few researchers have examined the intergenerational consequences of oxidative stress. Oxidative stress occurs in living organisms when reactive oxygen species remain unquenched by antioxidant defense systems and become detrimental to cells. In fish, it is unknown how maternal oxidative stress and antioxidant capacity influence offspring quality. The semelparous, migratory life history of Pacific salmon (Oncorhynchus spp.) provides a unique opportunity to explore intergenerational effects of oxidative stress. This study examined the effects of population origin on maternal and developing offspring oxidative stress and antioxidant capacity, and elucidated intergenerational relationships among populations of sockeye salmon (Oncorhynchus nerka) with varying migration effort. For three geographically distinct populations of Fraser River sockeye salmon (British Columbia, Canada), antioxidant capacity and oxidative stress were measured in adult female plasma, heart, brain, and liver, as well as in developing offspring until time of emergence. Maternal and offspring oxidative stress and antioxidant capacity varied among populations but patterns were not consistent across tissue/developmental stage. Furthermore, maternal oxidative stress and antioxidant capacity did not affect offspring oxidative stress and antioxidant capacity across any of the developmental stages or populations sampled. Our results revealed that offspring develop their endogenous antioxidant systems at varying rates across populations; however, this variability is overcome by the time of emergence. While offspring may be relying on maternally derived antioxidants in the initial stages of development, they rapidly develop their own antioxidant systems (mainly glutathione) during later stages of development. PMID:25660296

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

    SciTech Connect

    Berejikian, Barry A.; Athos, Jaime I.; Dittman, Andrew H.

    2004-07-01

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

  6. 50 CFR 660.412 - EFH identifications and descriptions for Pacific salmon.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 13 2014-10-01 2014-10-01 false EFH identifications and descriptions for Pacific salmon. 660.412 Section 660.412 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION, DEPARTMENT OF COMMERCE (CONTINUED) FISHERIES OFF...

  7. SALMON IN CRISIS: IN SEARCH OF A SOLUTION FOR THE PACIFIC NORTHWEST

    EPA Science Inventory

    Throughout the Pacific Northwest, since 1850, all wild salmon runs have declined and some have disappeared. Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline. Each year, hundreds of millions of dollars continue to be spent in variou...

  8. Oxygen uptake in Pacific salmon Oncorhynchus spp.: when ecology and physiology meet.

    PubMed

    Eliason, E J; Farrell, A P

    2016-01-01

    Over the past several decades, a substantial amount of research has examined how cardiorespiratory physiology supports the diverse activities performed throughout the life cycle of Pacific salmon, genus Oncorhynchus. Pioneering experiments emphasized the importance of aerobic scope in setting the functional thermal tolerance for activity in fishes. Variation in routine metabolism can have important performance and fitness consequences as it is related to dominance, aggression, boldness, territoriality, growth rate, postprandial oxygen consumption, life history, season, time of day, availability of shelter and social interactions. Wild fishes must perform many activities simultaneously (e.g. swim, obtain prey, avoid predators, compete, digest and reproduce) and oxygen delivery is allocated among competing organ systems according to the capacity of the heart to deliver blood. For example, salmonids that are simultaneously swimming and digesting trade-off maximum swimming performance in order to support the oxygen demands of digestion. As adult Pacific salmonids cease feeding in the ocean prior to their home migration, endogenous energy reserves and cardiac capacity are primarily partitioned among the demands for swimming upriver, sexual maturation and spawning behaviours. Furthermore, the upriver spawning migration is under strong selection pressure, given that Pacific salmonids are semelparous (single opportunity to spawn). Consequently, these fishes optimize energy expenditures in a number of ways: strong homing, precise migration timing, choosing forward-assist current paths and exploiting the boundary layer to avoid the strong currents in the middle of the river, using energetically efficient swimming speeds, and recovering rapidly from anaerobic swimming. Upon arrival at the spawning ground, remaining energy can be strategically allocated to the various spawning behaviours. Strong fidelity to natal streams has resulted in reproductively isolated populations that

  9. Oxygen uptake in Pacific salmon Oncorhynchus spp.: when ecology and physiology meet.

    PubMed

    Eliason, E J; Farrell, A P

    2016-01-01

    Over the past several decades, a substantial amount of research has examined how cardiorespiratory physiology supports the diverse activities performed throughout the life cycle of Pacific salmon, genus Oncorhynchus. Pioneering experiments emphasized the importance of aerobic scope in setting the functional thermal tolerance for activity in fishes. Variation in routine metabolism can have important performance and fitness consequences as it is related to dominance, aggression, boldness, territoriality, growth rate, postprandial oxygen consumption, life history, season, time of day, availability of shelter and social interactions. Wild fishes must perform many activities simultaneously (e.g. swim, obtain prey, avoid predators, compete, digest and reproduce) and oxygen delivery is allocated among competing organ systems according to the capacity of the heart to deliver blood. For example, salmonids that are simultaneously swimming and digesting trade-off maximum swimming performance in order to support the oxygen demands of digestion. As adult Pacific salmonids cease feeding in the ocean prior to their home migration, endogenous energy reserves and cardiac capacity are primarily partitioned among the demands for swimming upriver, sexual maturation and spawning behaviours. Furthermore, the upriver spawning migration is under strong selection pressure, given that Pacific salmonids are semelparous (single opportunity to spawn). Consequently, these fishes optimize energy expenditures in a number of ways: strong homing, precise migration timing, choosing forward-assist current paths and exploiting the boundary layer to avoid the strong currents in the middle of the river, using energetically efficient swimming speeds, and recovering rapidly from anaerobic swimming. Upon arrival at the spawning ground, remaining energy can be strategically allocated to the various spawning behaviours. Strong fidelity to natal streams has resulted in reproductively isolated populations that

  10. Conservation physiology in practice: how physiological knowledge has improved our ability to sustainably manage Pacific salmon during up-river migration

    PubMed Central

    Cooke, Steven J.; Hinch, Scott G.; Donaldson, Michael R.; Clark, Timothy D.; Eliason, Erika J.; Crossin, Glenn T.; Raby, Graham D.; Jeffries, Ken M.; Lapointe, Mike; Miller, Kristi; Patterson, David A.; Farrell, Anthony P.

    2012-01-01

    Despite growing interest in conservation physiology, practical examples of how physiology has helped to understand or to solve conservation problems remain scarce. Over the past decade, an interdisciplinary research team has used a conservation physiology approach to address topical conservation concerns for Pacific salmon. Here, we review how novel applications of tools such as physiological telemetry, functional genomics and laboratory experiments on cardiorespiratory physiology have shed light on the effect of fisheries capture and release, disease and individual condition, and stock-specific consequences of warming river temperatures, respectively, and discuss how these findings have or have not benefited Pacific salmon management. Overall, physiological tools have provided remarkable insights into the effects of fisheries capture and have helped to enhance techniques for facilitating recovery from fisheries capture. Stock-specific cardiorespiratory thresholds for thermal tolerances have been identified for sockeye salmon and can be used by managers to better predict migration success, representing a rare example that links a physiological scope to fitness in the wild population. Functional genomics approaches have identified physiological signatures predictive of individual migration mortality. Although fisheries managers are primarily concerned with population-level processes, understanding the causes of en route mortality provides a mechanistic explanation and can be used to refine management models. We discuss the challenges that we have overcome, as well as those that we continue to face, in making conservation physiology relevant to managers of Pacific salmon. PMID:22566681

  11. Physiological mechanisms of imprinting and homing migration in Pacific salmon Oncorhynchus spp.

    PubMed

    Ueda, H

    2012-07-01

    After several years of feeding at sea, salmonids have an amazing ability to migrate long distances from the open ocean to their natal stream to spawn. Three different research approaches from behavioural to molecular biological studies have been used to elucidate the physiological mechanisms underpinning salmonid imprinting and homing migration. The study was based on four anadromous Pacific salmon Oncorhynchus spp., pink salmon Oncorhynchus gorbuscha, chum salmon Oncorhynchus keta, sockeye salmon Oncorhynchus nerka and masu salmon Oncorhynchus masou, migrating from the North Pacific Ocean to the coast of Hokkaido, Japan, as well as lacustrine O. nerka and O. masou in Lake Toya, Hokkaido, where the lake serves as the model oceanic system. Behavioural studies using biotelemetry techniques showed swimming profiles from the Bering Sea to the coast of Hokkaido in O. keta as well as homing behaviours of lacustrine O. nerka and O. masou in Lake Toya. Endocrinological studies on hormone profiles in the brain-pituitary-gonad axis of O. keta, and lacustrine O. nerka identified the hormonal changes during homing migration. Neurophysiological studies revealed crucial roles of olfactory functions on imprinting and homing during downstream and upstream migration, respectively. These findings are discussed in relation to the physiological mechanisms of imprinting and homing migration in anadromous and lacustrine salmonids.

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

    USGS Publications Warehouse

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

    2003-01-01

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

  13. Signals of climate, conspecific density, and watershed features in patterns of homing and dispersal by Pacific salmon.

    PubMed

    Westley, Peter A H; Dittman, Andrew H; Ward, Eric J; Quinn, Thomas P

    2015-10-01

    It is widely assumed that rates of dispersal in animal populations are plastic in response to intrinsic and extrinsic cues, yet the factors influencing this plasticity are rarely known. This knowledge gap is surprising given the important role of dispersal in facilitating range shifts that may allow populations to persist in a rapidly changing global climate. We used two decades of tagging and recapture data from 19 hatchery populations of Oncorhynchus tshawytscha (Chinook salmon) in the Columbia River, USA, to quantify the effects of regional and local climate conditions, density dependence, watershed features such as area and position on the landscape, and direct anthropogenic influence on dispersal rates by adult salmon during the breeding season. We found that the probability of dispersal, termed "straying" in salmon, is plastic in'response to multiple factors and that populations showed varied responses that were largely idiosyncratic. A regional climate index (Pacific Decadal Oscillation), water temperatures in the mainstem Columbia River that was commonly experience by populations during migration, water temperatures in local subbasins unique to each population during the breeding season, migration distance, and density dependence had the strongest effects on dispersal. Patterns of dispersal plasticity in response to commonly experienced conditions were consistent with gene by environment interactions, though we are tentative about this interpretation given the domesticated history of these populations. Overall, our results warn against attempts to predict future range shifts of migratory species without considering population-specific dispersal plasticity, and also caution against the use of few populations to infer species-level patterns. Ultimately, our results provide evidence that analyses that examine the response of dispersal to single factors may be misleading. PMID:26649402

  14. Evolutionary responses by native species to major anthropogenic changes to their ecosystems: Pacific salmon in the Columbia River hydropower system.

    PubMed

    Waples, Robin S; Zabel, Richard W; Scheuerell, Mark D; Sanderson, Beth L

    2008-01-01

    The human footprint is now large in all the Earth's ecosystems, and construction of large dams in major river basins is among the anthropogenic changes that have had the most profound ecological consequences, particularly for migratory fishes. In the Columbia River basin of the western USA, considerable effort has been directed toward evaluating demographic effects of dams, yet little attention has been paid to evolutionary responses of migratory salmon to altered selective regimes. Here we make a first attempt to address this information gap. Transformation of the free-flowing Columbia River into a series of slack-water reservoirs has relaxed selection for adults capable of migrating long distances upstream against strong flows; conditions now favour fish capable of migrating through lakes and finding and navigating fish ladders. Juveniles must now be capable of surviving passage through multiple dams or collection and transportation around the dams. River flow patterns deliver some groups of juvenile salmon to the estuary later than is optimal for ocean survival, but countervailing selective pressures might constrain an evolutionary response toward earlier migration timing. Dams have increased the cost of migration, which reduces energy available for sexual selection and favours a nonmigratory life history. Reservoirs are a benign environment for many non-native species that are competitors with or predators on salmon, and evolutionary responses are likely (but undocumented). More research is needed to tease apart the relative importance of evolutionary vs. plastic responses of salmon to these environmental changes; this research is logistically challenging for species with life histories like Pacific salmon, but results should substantially improve our understanding of key processes. If the Columbia River is ever returned to a quasinatural, free-flowing state, remaining populations might face a Darwinian debt (and temporarily reduced fitness) as they struggle to

  15. Evolutionary responses by native species to major anthropogenic changes to their ecosystems: Pacific salmon in the Columbia River hydropower system.

    PubMed

    Waples, Robin S; Zabel, Richard W; Scheuerell, Mark D; Sanderson, Beth L

    2008-01-01

    The human footprint is now large in all the Earth's ecosystems, and construction of large dams in major river basins is among the anthropogenic changes that have had the most profound ecological consequences, particularly for migratory fishes. In the Columbia River basin of the western USA, considerable effort has been directed toward evaluating demographic effects of dams, yet little attention has been paid to evolutionary responses of migratory salmon to altered selective regimes. Here we make a first attempt to address this information gap. Transformation of the free-flowing Columbia River into a series of slack-water reservoirs has relaxed selection for adults capable of migrating long distances upstream against strong flows; conditions now favour fish capable of migrating through lakes and finding and navigating fish ladders. Juveniles must now be capable of surviving passage through multiple dams or collection and transportation around the dams. River flow patterns deliver some groups of juvenile salmon to the estuary later than is optimal for ocean survival, but countervailing selective pressures might constrain an evolutionary response toward earlier migration timing. Dams have increased the cost of migration, which reduces energy available for sexual selection and favours a nonmigratory life history. Reservoirs are a benign environment for many non-native species that are competitors with or predators on salmon, and evolutionary responses are likely (but undocumented). More research is needed to tease apart the relative importance of evolutionary vs. plastic responses of salmon to these environmental changes; this research is logistically challenging for species with life histories like Pacific salmon, but results should substantially improve our understanding of key processes. If the Columbia River is ever returned to a quasinatural, free-flowing state, remaining populations might face a Darwinian debt (and temporarily reduced fitness) as they struggle to

  16. Variation in responses to spawning Pacific salmon among three south-eastern Alaska streams

    USGS Publications Warehouse

    Chaloner, D.T.; Lamberti, G.A.; Merritt, R.W.; Mitchell, N.L.; Ostrom, P.H.; Wipfli, M.S.

    2004-01-01

    1. Pacific salmon are thought to stimulate the productivity of the fresh waters in which they spawn by fertilising them with marine-derived nutrients (MDN). We compared the influence of salmon spawners on surface streamwater chemistry and benthic biota among three southeastern Alaska streams. Within each stream, reaches up- and downstream of barriers to salmon migration were sampled during or soon after spawners entered the streams. 2. Within streams, concentrations of dissolved ammonium and soluble reactive phosphorus (SRP), abundance of epilithon (chlorophyll a and ash-free dry mass) and biomass of chironomids were significantly higher in reaches with salmon spawners. In contrast, biomass of the mayflies Epeorus spp. and Rhithrogena spp. was significantly higher in reaches lacking spawners. 3. Among streams, significant differences were found in concentrations of dissolved ammonium, dissolved organic carbon, nitrate and SRP, abundance of epilithon, and the biomass of chironomids and Rhithrogena. These differences did not appear to reflect differences among streams in spawner density, nor the changes in water chemistry resulting from salmon spawners. 4. Our results suggest that the 'enrichment' effect of salmon spawners (e.g. increased streamwater nutrient concentrations) was balanced by other concurrent effects of spawners on streams (e.g. sediment disturbance). Furthermore, the collective effect of spawners on lotic ecosystems is likely to be constrained by conditions unique to individual streams, such as temperature, background water chemistry and light attenuation.

  17. Assessing sufficiency of thermal riverscapes for resilient salmon and steelhead populations

    EPA Science Inventory

    Resilient salmon populations require river networks that provide water temperature regimes sufficient to support a diversity of salmonid life histories across space and time. Efforts to protect, enhance and restore watershed thermal regimes for salmon may target specific location...

  18. Indirect genetic effects underlie oxygen-limited thermal tolerance within a coastal population of chinook salmon.

    PubMed

    Muñoz, Nicolas J; Anttila, Katja; Chen, Zhongqi; Heath, John W; Farrell, Anthony P; Neff, Bryan D

    2014-08-22

    With global temperatures projected to surpass the limits of thermal tolerance for many species, evaluating the heritable variation underlying thermal tolerance is critical for understanding the potential for adaptation to climate change. We examined the evolutionary potential of thermal tolerance within a population of chinook salmon (Oncorhynchus tshawytscha) by conducting a full-factorial breeding design and measuring the thermal performance of cardiac function and the critical thermal maximum (CTmax) of offspring from each family. Additive genetic variation in offspring phenotype was mostly negligible, although these direct genetic effects explained 53% of the variation in resting heart rate (fH). Conversely, maternal effects had a significant influence on resting fH, scope for fH, cardiac arrhythmia temperature and CTmax. These maternal effects were associated with egg size, as indicated by strong relationships between the mean egg diameter of mothers and offspring thermal tolerance. Because egg size can be highly heritable in chinook salmon, our finding indicates that the maternal effects of egg size constitute an indirect genetic effect contributing to thermal tolerance. Such indirect genetic effects could accelerate evolutionary responses to the selection imposed by rising temperatures and could contribute to the population-specific thermal tolerance that has recently been uncovered among Pacific salmon populations. PMID:25009055

  19. FACTS, FANTASIES, AND FORECASTS: THE FUTURE OF WILD PACIFIC SALMON

    EPA Science Inventory

    Throughout the far western contiguous United States (California, Oregon, Washington, and Idaho), many wild salmon stocks have declined and some have disappeared. The decline has taken place over the past 150 years, but there have been decades when the numbers increased. Overall...

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

    USGS Publications Warehouse

    Rinella, D.J.; Wipfli, M.S.; Stricker, C.A.; Heintz, R.A.; Rinella, M.J.

    2012-01-01

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

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

    USGS Publications Warehouse

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

    2012-01-01

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

  2. ECOLOGICAL AND WATER QUALITY CONSEQUENCES OF NUTRIENT ADDITION FOR SALMON RESTORATION IN THE PACIFIC NORTHWEST OF NORTH AMERICA

    EPA Science Inventory

    Salmon runs have declined over the past two centuries in the Pacific Northwest region of North America. Reduced inputs of salmon-derived organic matter and nutrients (SDN) may limit freshwater production and thus establish a negative feedback loop affecting future generations of...

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

    SciTech Connect

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

    2002-08-01

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

  4. Nonnative Pacific salmon alter hot spots of sediment nitrification in Great Lakes tributaries

    NASA Astrophysics Data System (ADS)

    Levi, Peter S.; Tank, Jennifer L.

    2013-06-01

    Biogeochemical transformations may represent an important pathway influencing the fate of nutrient subsidies in stream ecosystems. Pacific salmon (Oncorhynchus spp.) provide an ammonium (NH4+) subsidy to streams during their annual spawning runs, which may be transformed to nitrate (NO3-) via sediment nitrification. Increases in either forms of dissolved inorganic nitrogen may have ecosystem effects both at the reach and watershed scales, including the fertilization of algal biofilms and elevated export of nutrients to downstream ecosystems. In the nonnative range of salmon, where spawning runs are a relatively new phenomenon, few studies have explored the effect of introduced salmon on ecosystem processes. To assess the effect of nonnative salmon on dissolved inorganic nitrogen dynamics in Great Lakes tributaries, we quantified sediment nitrification in five streams before, during, and after the spawning run in 2009. Overall, sediment nitrification rates were higher in the channel thalweg (mean ± SE = 1.9 ± 0.1 mg N/gAFDM/d) compared to channel margins (mean ± SE = 0.9 ± 0.1 mg N/gAFDM/d). In the two streams with the largest salmon runs, nitrification was highest in the channel thalweg prior to salmon, but margin sediments had higher nitrification during the run. Among all streams, variation in nitrification rates was habitat specific, predicted by exchangeable NH4+ in sediments from the thalweg and predicted by salmon biomass for sediments in the channel margin. Nonnative salmon provide a pulsed source of inorganic nitrogen to Great Lakes tributaries, yet dissimilatory biogeochemical transformations such as nitrification may alter the form of the NH4+ subsidy and potentially influence downstream lakes via export of both NH4+ and NO3-.

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

    SciTech Connect

    Berejikian, Barry A.

    2005-11-01

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

  6. An Investigation into the Poor Survival of an Endangered Coho Salmon Population

    PubMed Central

    Chittenden, Cedar M.; Melnychuk, Michael C.; Welch, David W.; McKinley, R. Scott

    2010-01-01

    To investigate reasons for the decline of an endangered population of coho salmon (O. kisutch), 190 smolts were acoustically tagged during three consecutive years and their movements and survival were estimated using the Pacific Ocean Shelf Tracking project (POST) array. Median travel times of the Thompson River coho salmon smolts to the lower Fraser River sub-array were 16, 12 and 10 days during 2004, 2005 and 2006, respectively. Few smolts were recorded on marine arrays. Freshwater survival rates of the tagged smolts during their downstream migration were 0.0–5.6% (0.0–9.0% s.e.) in 2004, 7.0% (6.2% s.e.) in 2005, and 50.9% (18.6% s.e.) in 2006. Overall smolt-to-adult return rates exhibited a similar pattern, which suggests that low freshwater survival rates of out-migrating smolts may be a primary reason for the poor conservation status of this endangered coho salmon population. PMID:20526367

  7. Pesticides and PCBs in Pacific salmon (Oncorhynchus tshawytscha and O. kisutch) from Puget Sound, Washington

    SciTech Connect

    O`Neill, S.M.; West, J.E.

    1995-12-31

    The Washington Department of Fish and Wildlife initiated a long-term study to monitor levels of contaminants in two species of Pacific salmon (Oncorhynchus tshawytscha and O. kisutch) and other marine fishes of Puget Sound. The study is one component of the Puget Sound Ambient Monitoring Program (PSAMP), a multi-agency effort to assess the environmental health of Puget Sound. Here the authors summarize results from their ongoing study of O. tshawytscha and O. kisutch. Samples of muscle tissue were collected for chemical analyses from adult salmon that were purchased from licensed fish buyers or treaty tribal fisherman. From 1992 through 1994, both salmon species were sampled at seven fishing areas in marine waters and river mouths of Puget Sound. 4,4-DDE and 4,4-DDD, metabolites of the pesticide DDT, and polychlorinated biphenyls (PCBS) were consistently detected in both species and were consistently higher in O. tshawytscha. Low to moderate concentrations of DDT metabolites (3 to 59 ug/kg wet weight) were detected in the salmon samples but were seldom detected in other fish species sampled by PSAMP. Total PCBs concentrations (Arochlor 1254 + 1260) ranged from 10 to 211 ug/kg wet weight in 0. tshawytscha, with many samples containing PCBs concentrations similar to those detected in benthic flatfish, (Pleuronectes vetulus), sampled from urbanized embayments. A stepwise linear regression model was used to identify parameters correlated with accumulation of PCBs and DDT metabolites in salmon. In addition to species differences, factors such as fish age, percent lipids and sampling location may affect the accumulation of these contaminants. Results of this study are contrasted with contaminant levels previously reported for Canadian and Alaskan Pacific salmon. Possible sources of contaminants are outlined.

  8. Elevated streamflows increase dam passage by juvenile coho salmon during winter: Implications of climate change in the Pacific Northwest

    USGS Publications Warehouse

    Kock, Tobias J.; Liedtke, Theresa L.; Rondorf, Dennis W.; Serl, John D.; Kohn, Mike; Bumbaco, Karin A.

    2012-01-01

    A 4-year evaluation was conducted to determine the proportion of juvenile coho salmon Oncorhynchus kisutch passing Cowlitz Falls Dam, on the Cowlitz River, Washington, during winter. River and reservoir populations of coho salmon parr were monitored using radiotelemetry to determine if streamflow increases resulted in increased downstream movement and dam passage. This was of interest because fish that pass downstream of Cowlitz Falls Dam become landlocked in Riffe Lake and are lost to the anadromous population. Higher proportions of reservoir-released fish (0.391-0.480) passed Cowlitz Falls Dam than did river-released fish (0.037-0.119). Event-time analyses demonstrated that streamflow increases were important predictors of dam passage rates during the study. The estimated effect of increasing streamflows on the risk of dam passage varied annually and ranged from 9% to 75% for every 28.3 m3/s increase in streamflow. These results have current management implications because they demonstrate the significance of dam passage by juvenile coho salmon during winter months when juvenile fish collection facilities are typically not operating. The results also have future management implications because climate change predictions suggest that peak streamflow timing for many watersheds in the Pacific Northwest will shift from late spring and early summer to winter. Increased occurrence of intense winter flood events is also expected. Our results demonstrate that juvenile coho salmon respond readily to streamflow increases and initiate downstream movements during winter months, which could result in increased passage at dams during these periods if climate change predictions are realized in the coming decades.

  9. Congener Patterns of Persistent Organic Pollutants Establish the Extent of Contaminant Biotransport by Pacific Salmon in the Great Lakes.

    PubMed

    Gerig, Brandon S; Chaloner, Dominic T; Janetski, David J; Rediske, Richard R; O'Keefe, James P; Moerke, Ashley H; Lamberti, Gary A

    2016-01-19

    In the Great Lakes, introduced Pacific salmon (Oncorhynchus spp.) can transport persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), to new environments during their spawning migrations. To explore the nature and extent of POP biotransport by salmon, we compared 58 PCB and 6 PBDE congeners found in spawning salmon directly to those in resident stream fish. We hypothesized that stream fish exposed to salmon spawners would have congener patterns similar to those of salmon, the presumed contaminant source. Using permutational multivariate analysis of variance (PERMANOVA) and nonmetric multidimensional scaling (NMDS), we found that POP congener patterns of Pacific salmon varied among regions in the Great Lakes basin (i.e., Lake Huron, Lake Michigan, or Lake Superior), tissue type (whole fish or eggs), and contaminant type (PCB or PBDE). For stream-resident fish, POP congener pattern was influenced by the presence of salmon, location (i.e., Great Lakes Basin), and species identity (i.e., brook trout [Salvelinus fontinalis] or mottled sculpin [Cottus bairdii]). Similarity in congener patterns indicated that salmon are a source of POPs to brook trout in stream reaches receiving salmon spawners from Lake Michigan and Lake Huron but not from Lake Superior. Congener patterns of mottled sculpin differed from those of brook trout and salmon, suggesting that brook trout and mottled sculpin either use salmon tissue to differing degrees, acquire POPs from different dietary sources, or bioaccumulate or metabolize POPs differently. Overall, our analyses identified the important role of salmon in contaminant biotransport but also demonstrated that the extent of salmon-mediated POP transfer and uptake in Great Lakes tributaries is location- and species-specific.

  10. Oxygen removal from water versus arterial oxygen delivery: calibrating the Fick equation in Pacific salmon.

    PubMed

    Farrell, Anthony P; Eliason, Erika J; Clark, Timothy D; Steinhausen, Maria F

    2014-10-01

    While it is well known that O2 is directly removed from the water by skin and gill tissues of fish, the mismatch between O2 removal from water (O2 uptake; [Formula: see text]) and the O2 delivered to tissues by the primary circulation (O2 consumption; [Formula: see text]) has never been measured directly. Using data from four recent studies that simultaneously measured [Formula: see text] and [Formula: see text] in 2-5 kg Pacific salmon, our analysis revealed that sockeye salmon can remove an additional 12-48 % more O2 from the water than the primary circulation delivers to the systemic tissues. This percentage did not change significantly during swimming activity, a result that contradicts an earlier prediction that the difference should decrease when [Formula: see text] increases during exercise. In resting Chinook salmon, a similar percentage difference in simultaneously measured [Formula: see text] and [Formula: see text] was observed, yet the difference tended to disappear during acute heat stress to a near lethal temperature. These results emphasize that caution should be exercised when using the Fick equation to estimate cardiac output because the overestimate of cardiac output that results from using the Fick equation in Pacific salmon is not small, may not be fixed and may exist in other teleosts. PMID:25031037

  11. Nutrient additions to mitigate for loss of Pacific salmon: consequences for stream biofilm and nutrient dynamics

    USGS Publications Warehouse

    Marcarelli, Amy M.; Baxter, Colden V.; Wipfli, Mark S.

    2014-01-01

    Mitigation activities designed to supplement nutrient and organic matter inputs to streams experiencing decline or loss of Pacific salmon typically presuppose that an important pathway by which salmon nutrients are moved to fish (anadromous and/or resident) is via nutrient incorporation by biofilms and subsequent bottom-up stimulation of biofilm production, which is nutrient-limited in many ecosystems where salmon returns have declined. Our objective was to quantify the magnitude of nutrient incorporation and biofilm dynamics that underpin this indirect pathway in response to experimental additions of salmon carcasses and pelletized fish meal (a.k.a., salmon carcass analogs) to 500-m reaches of central Idaho streams over three years. Biofilm standing crops increased 2–8-fold and incorporated marine-derived nutrients (measured using 15N and 13C) in the month following treatment, but these responses did not persist year-to-year. Biofilms were nitrogen (N) limited before treatments, and remained N limited in analog, but not carcass-treated reaches. Despite these biofilm responses, in the month following treatment total N load was equal to 33–47% of the N added to the treated reaches, and N spiraling measurements suggested that as much as 20%, but more likely 2–3% of added N was taken up by microbes. Design of biologically and cost-effective strategies for nutrient addition will require understanding the rates at which stream microbes take up nutrients and the downstream distance traveled by exported nutrients.

  12. [Ultrastructure of melanocytes from retina and choroid of the Pacific salmon].

    PubMed

    Zagal'skaia, E O

    2001-01-01

    The ultrastructure of the retina and choroid cells in three species of the Pacific salmon, Oncohrynchus gorbuscha, O. keta and O. masou, was studied. The structure of retina pigment cells is similar in all the three species, only a small difference was found in the percentage of lengthened and rounded forms of melanosomes. Melanocytes of the masu salmon differ also in the structure of their nuclei. The pigment cells of choroid differ from those of retina by a more extended form of melanosomes and by the presence of less rounded melanosomes. In the chum salmon retina we found electron lucent "contact vesicles", whose assignment is open to discussion. In retina pigment cells of the masu salmon smolts ready for migration, the activity of Golgi appararus rises, mitochondria and mature melanosomes increase in number. The choroid pigment cells are slightly swollen, their processes more often and deeper penetrate into the walls of vessels, down to the endothelium. Results of the experiment with the application of an artificial magnetic field (AMF) have shown that the retina and choroid pigment cells in the masu salmon fry react to the field of a certain direction. The phenomenon of magnetosensitivity of pigment cells is discussed in addition to their possible involvement in magnetoreception.

  13. Evidence for geomagnetic imprinting as a homing mechanism in Pacific salmon.

    PubMed

    Putman, Nathan F; Lohmann, Kenneth J; Putman, Emily M; Quinn, Thomas P; Klimley, A Peter; Noakes, David L G

    2013-02-18

    In the final phase of their spawning migration, Pacific salmon use chemical cues to identify their home river, but how they navigate from the open ocean to the correct coastal area has remained enigmatic. To test the hypothesis that salmon imprint on the magnetic field that exists where they first enter the sea and later seek the same field upon return, we analyzed a 56-year fisheries data set on Fraser River sockeye salmon, which must detour around Vancouver Island to approach the river through either a northern or southern passageway. We found that the proportion of salmon using each route was predicted by geomagnetic field drift: the more the field at a passage entrance diverged from the field at the river mouth, the fewer fish used the passage. We also found that more fish used the northern passage in years with warmer sea surface temperature (presumably because fish were constrained to more northern latitudes). Field drift accounted for 16% of the variation in migratory route used, temperature 22%, and the interaction between these variables 28%. These results provide the first empirical evidence of geomagnetic imprinting in any species and imply that forecasting salmon movements is possible using geomagnetic models. PMID:23394828

  14. Timing games in the reproductive phenology of female pacific salmon (Oncorhynchus spp.).

    PubMed

    Morbey, Yolanda E; Ydenberg, Ronald C

    2003-02-01

    We use a game-theoretic framework to investigate the reproductive phenology of female kokanee (Oncorhynchus nerka). As in the other semelparous species of Pacific salmon, females construct nests in gravel, spawn with males, bury their fertilized eggs, and defend their nest sites until they die several days later. Later-breeding females may reuse previous nest sites, and their digging behavior is thought to subject previously buried eggs to mortality. Using game-theoretic models, we show that females can reduce this risk by allocating resources to longevity (the period between arrival and death) as opposed to eggs. Waiting before territory settlement is also expected if it allows females to conserve energy and delay senescence. The models demonstrate how these costs and benefits interact to select for a seasonal decline in longevity, a well-known phenomenon in the salmonid literature, and a seasonal decline in wait duration. Both of these predictions were supported in a field study of kokanee. Female state of reproductive maturity was the most important proximate factor causing variation in longevity and wait duration. With more than 30% of territories being reused, dig-up is likely an important selective force in this population.

  15. Genetic Structure of Chum Salmon (Oncorhynchus Keta) Populations in the Lower Columbia River: Are Chum Salmon in Cascade Tributaries Remnant Populations?

    SciTech Connect

    Small, Maureen P.; Pichahchy, A.E.; Von Bargen, J.F.; Young, S.F.

    2004-09-01

    Prior to the 1950's, the lower Columbia River drainage supported a run of over a million chum salmon composed of at least 16 populations. By the late 1950's, over-fishing and habitat destruction had decreased the run to as little as a few hundred fish. With the exception of Grays River in the coastal region of the Columbia River and an aggregation of chum salmon spawning in creeks and the mainstem near Bonneville Dam in the Columbia Gorge region, most populations were considered extinct. However, over the years, WDFW biologists detected chum salmon spawning in tributaries originating in the Cascade Range: the Cowlitz, Lewis, and Washougal rivers. Further, chum salmon in the Cowlitz River appeared to have summer and fall run-timings. To assess whether Cascade spawners were strays from Grays River and Gorge regions or remnants of former populations, chum salmon from the Coastal, Cascade and Gorge regions were characterized genetically at 17 microsatellite loci. With the exception of Washougal River chum salmon, which grouped strongly with the Gorge genetic group, significant heterogeneity in genotype distributions were detected between regions and genotype distributions overlapped among collections within regions. In a neighbor-joining consensus tree, regional groups occupied branches with over 77% bootstrap support. In assignment tests, over 63% of individuals were correctly assigned back to region of origin although an average of 29% assigned to river of origin. Genetic distinction of Cascade region chum salmon was similar to distinction of Coastal and Gorge chum salmon and the Cascade region chum salmon had twice the number of private regional alleles. Further, the Cowlitz River supports the only summer chum salmon run in the Columbia River drainage. We propose that chum salmon in the Cascade region are remnants of original populations. We attribute the strong divergence between regional groups to diverse ecological conditions in each region, which promoted

  16. Cortisol and Pacific Salmon: A New Look at the Role of Stress Hormones in Olfaction and Home-stream Migration.

    PubMed

    Carruth, Laura L; Jones, Richard E; Norris, David O

    2002-07-01

    Pacific salmon (genus Oncorhynchus) exhibit an interesting and uncommon life-history pattern that combines semelparity, anadromy, and navigation (homing). During smoltification, young salmon imprint on the chemical composition of their natal stream water (the home-stream olfactory bouquet or "HSOB"); they then migrate to the ocean where they spend a few years feeding prior to migrating back to their natal freshwater stream to spawn. Upstream migration is guided by the amazing ability to discriminate between the chemical compositions of different stream waters and thus identify and travel to their home-stream. Pacific salmon demonstrate marked somatic and neural degeneration changes during home-stream migration and at the spawning grounds. The appearance of these pathologies is correlated with a marked elevation in plasma cortisol levels. While the mechanisms of salmonid homing are not completely understood, it is known that adult salmon continuously utilize two of their primary sensory systems, olfaction and vision, during homing. Olfaction is the primary sensory system involved in freshwater homing and "HSOB" recognition, and will be emphasized here. Previously, we proposed that the increase in plasma cortisol during Pacific salmon home-stream migration is adaptive because it enhances the salmon's ability to recall the imprinted memory of the "HSOB" (Carruth, 1998; Carruth et al., 2000b). Elevated plasma concentrations of cortisol could prime the hippocampus or other olfactory regions of the brain to recall this memory and, therefore, aid in directing the fish to their natal stream. Thus, specific responses of salmon to stressors could enhance reproductive success.

  17. Variation in the population structure of Yukon River chum and coho salmon: Evaluating the potential impact of localized habitat degradation

    USGS Publications Warehouse

    Olsen, J.B.; Spearman, W.J.; Sage, G.K.; Miller, S.J.; Flannery, B.G.; Wenburg, J.K.

    2004-01-01

    We used microsatellite and mitochondrial DNA-restriction fragment length polymorphism (mtDNA-RFLP) analyses to test the hypothesis that chum salmon Oncorhynchus keta and coho salmon O. kisutch in the Yukon River, Alaska, exhibit population structure at differing spatial scales. If the hypothesis is true, then the risk of losing genetic diversity because of habitat degradation from a gold mine near a Yukon River tributary could differ between the two species. For each species, collections were made from two tributaries in both the Innoko and Tanana rivers, which are tributaries to the lower and middle Yukon River. The results revealed a large difference in the degree and spatial distribution of population structure between the two species. For chum salmon, the microsatellite loci (F-statistic [FST] = 0.021) and mtDNA (F ST = -0.008) revealed a low degree of interpopulation genetic diversity on a relatively large geographic scale. This large-scale population structure should minimize, although not eliminate, the risk of genetic diversity loss due to localized habitat degradation. For coho salmon, the microsatellites (FST = 0.091) and mtDNA (FST = 0.586) revealed a high degree of interpopulation genetic diversity on a relatively small geographic scale. This small-scale population structure suggests that coho salmon are at a relatively high risk of losing genetic diversity due to lo-calized habitat degradation. Our study underscores the importance of a multispecies approach for evaluating the potential impact of land-use activities on the genetic diversity of Pacific salmon.

  18. A three-species model explaining cyclic dominance of Pacific salmon.

    PubMed

    Guill, Christian; Drossel, Barbara; Just, Wolfram; Carmack, Eddy

    2011-05-01

    The four-year oscillations of the number of spawning sockeye salmon (Oncorhynchus nerka) that return to their native stream within the Fraser River basin in Canada are a striking example of population oscillations. The period of the oscillation corresponds to the dominant generation time of these fish. Various-not fully convincing-explanations for these oscillations have been proposed, including stochastic influences, depensatory fishing, or genetic effects. Here, we show that the oscillations can be explained as an attractor of the population dynamics, resulting from a strong resonance near a Neimark Sacker bifurcation. This explains not only the long-term persistence of these oscillations, but also reproduces correctly the empirical sequence of salmon abundance within one period of the oscillations. Furthermore, it explains the observation that these oscillations occur only in sockeye stocks originating from large oligotrophic lakes, and that they are usually not observed in salmon species that have a longer generation time.

  19. Changes in ligand binding to GABAA receptor sites in pacific salmon (Oncorhynchus) brain during spawning migration and "aging".

    PubMed

    Erdö, S L; Meyer, D L; Malz, C R; Hofmann, M H; Ebbesson, S O

    1992-01-01

    When several years old, pacific salmon return to the site of birth, to spawn. At this time, a rapid aging process begins and the fish die within a few weeks after reproducing. Age-related changes of high and low affinity GABA binding sites were studied in salmon brains at three different phases of the spawning migration, i.e. shortly after returning to the natal stream, at the time of spawning, and thereafter. High affinity GABA binding slightly increased while the fish deteriorated. The low affinity component showed a remarkable decrease in density and a concomitant increase in affinity during this final episode of salmon life.

  20. The hydrology of four streams in western Washington as related to several Pacific salmon species

    USGS Publications Warehouse

    Collings, Michael R.; Smith, Ronald W.; Higgins, G.T.

    1972-01-01

    Enhancement-or possibly even preservation-of the Pacific salmon hinges on the careful planning and proper management of the streamflow upon which they depend for spawning. Most spawning activity occurs on reaches of streams where specific hydraulic conditions exist and where stream-channel characteristics and water-quality criteria are met. The present report is the first of a series and is used to present the method of determining preferred spawning conditions and results of the investigation of 129 measurements on 14 study reaches of the Dewatto, Cedar, Kalama, and North 'Fork Nooksack Rivers. Subsequent reports, using the same method will present analyses and preferred spawning and rearing discharges for other streams used by salmon. The method consists of measuring water depth and velocities to designate, from area-(spawnable) discharge curves, peak, preferred spawning discharges for fall chinook, spring chinook, sockeye, and coho salmon at each reach on each river. Also, streambed gravels, water temperature, suspended sediment, dissolved oxygen, and specific conductance are used to help evaluate river conditions during spawning. In examining the repeatability of the method, tested by analyzing independently each of selected pairs of adjacent reaches on the Cedar River, it was found that the preferred peak discharges from the comparisons varied 4.6 percent for the average of four species and two pairs of reaches. Peak spawning discharges ranged, for the four salmon species on each of the three study reaches of each river, from 50 to 140 cfs (cubic feet per second) on Dewatto River, from 230 to 510 cfs on Cedar River, from 245 to 800 cfs on Kalama River, and from 195 to 710 cfs on North Fork Nooksack River. The results indicate that the methods used and the probable discharge values determined are reasonable and, if economically justified, may be used to select discharges, for salmon spawning and rearing.

  1. 50 CFR 226.217 - Critical habitat for the Gulf of Maine Distinct Population Segment of Atlantic Salmon (Salmo salar).

    Code of Federal Regulations, 2010 CFR

    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...

  2. Population Structure of Columbia River Basin Chinook Salmon and Steelhead Trout, Technical Report 2001.

    SciTech Connect

    Brannon, E.L.; National Science Foundation

    2002-08-01

    The population structure of chinook salmon and steelhead trout is presented as an assimilation of the life history forms that have evolved in synchrony with diverse and complex environments over their Pacific range. As poikilotherms, temperature is described as the overwhelming environmental influence that determines what life history options occur and where they are distributed. The different populations represent ecological types referred to as spring-, summer-, fall, and winter-run segments, as well as stream- and ocean-type, or stream- and ocean-maturing life history forms. However, they are more correctly described as a continuum of forms that fall along a temporal cline related to incubation and rearing temperatures that determine spawn timing and juvenile residence patterns. Once new habitats are colonized, members of the founding populations spread through adaptive evolution to assume complementary life history strategies. The related population units are collectively referred to as a metapopulation, and members most closely associated within common temporal and geographic boundaries are designated as first-order metapopulations. Population structure of chinook salmon and steelhead in the Columbia Basin, therefore, is the reflection of the genetic composition of the founding source or sources within the respective region, shaped by the environment, principally temperature, that defines life history evolutionary strategy to maximize fitness under the conditions delineated. The complexity of structure rests with the diversity of opportunities over the elevations that exist within the Basin. Consistent with natural selection, rather than simply attempting to preserve populations, the challenge is to provide opportunities to expand their range to new or restored habitat that can accommodate genetic adaptation as directional environmental changes are elaborated. Artificial propagation can have a critical role in this process, and the emphasis must be placed on

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

    USGS Publications Warehouse

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

    2016-01-01

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

  4. Stream Physical Characteristics Impact Habitat Quality for Pacific Salmon in Two Temperate Coastal Watersheds

    PubMed Central

    Fellman, Jason B.; Hood, Eran; Dryer, William; Pyare, Sanjay

    2015-01-01

    Climate warming is likely to cause both indirect and direct impacts on the biophysical properties of stream ecosystems especially in regions that support societally important fish species such as Pacific salmon. We studied the seasonal variability and interaction between stream temperature and DO in a low-gradient, forested stream and a glacial-fed stream in coastal southeast Alaska to assess how these key physical parameters impact freshwater habitat quality for salmon. We also use multiple regression analysis to evaluate how discharge and air temperature influence the seasonal patterns in stream temperature and DO. Mean daily stream temperature ranged from 1.1 to 16.4°C in non-glacial Peterson Creek but only 1.0 to 8.8°C in glacial-fed Cowee Creek, reflecting the strong moderating influence glacier meltwater had on stream temperature. Peterson Creek had mean daily DO concentrations ranging from 3.8 to 14.1 mg L−1 suggesting future climate changes could result in an even greater depletion in DO. Mean daily stream temperature strongly controlled mean daily DO in both Peterson (R2=0.82, P<0.01) and Cowee Creek (R2=0.93, P<0.01). However, DO in Peterson Creek was mildly related to stream temperature (R2=0.15, P<0.01) and strongly influenced by discharge (R2=0.46, P<0.01) on days when stream temperature exceeded 10°C. Moreover, Peterson Creek had DO values that were particularly low (<5.0 mg L−1) on days when discharge was low but also when spawning salmon were abundant. Our results demonstrate the complexity of stream temperature and DO regimes in coastal temperate watersheds and highlight the need for watershed managers to move towards multi-factor risk assessment of potential habitat quality for salmon rather than single factor assessments alone. PMID:26222506

  5. Strong resonance explains cycles in sockeye salmon populations

    NASA Astrophysics Data System (ADS)

    Guill, Christian; Drossel, Barbara

    2010-03-01

    The number of spawning sockeye salmon that return to their native streams in the Fraser river basin exhibit striking four-year oscillations, the dimension of which being no less notable than the widely known cycles of lynx and snowshoe hare in Canada. The period of the oscillation corresponds to the dominant generation time of these fish, and the phase differs between different stocks. Various not fully convincing explanations have been attempted, ascribing this phenomenon to transient effects, to stochastic influences, to depensatory predation, or to genetic effects. We show that these oscillations can be explained as a stable dynamical attractor of the population dynamics, resulting from a strong resonance near a Neimark Sacker bifurcation. This explains not only the long-term persistence of these oscillations, but also reproduces correctly the sequence of two strong years followed by two weak years. Furthermore, it explains the observations that the oscillations occur only in oligotrophic lakes, and that they do not occur in salmon species that have a longer generation time.

  6. Climate change sensitivity index for Pacific salmon habitat in southeast Alaska.

    PubMed

    Shanley, Colin S; Albert, David M

    2014-01-01

    Global climate change may become one of the most pressing challenges to Pacific Salmon conservation and management for southeast Alaska in the 21st Century. Predicted hydrologic change associated with climate change will likely challenge the ability of specific stocks to adapt to new flow regimes and resulting shifts in spawning and rearing habitats. Current research suggests egg-to-fry survival may be one of the most important freshwater limiting factors in Pacific Salmon's northern range due to more frequent flooding events predicted to scour eggs from mobile spawning substrates. A watershed-scale hydroclimatic sensitivity index was developed to map this hypothesis with an historical stream gauge station dataset and monthly multiple regression-based discharge models. The relative change from present to future watershed conditions predicted for the spawning and incubation period (September to March) was quantified using an ensemble global climate model average (ECHAM5, HadCM3, and CGCM3.1) and three global greenhouse gas emission scenarios (B1, A1B, and A2) projected to the year 2080. The models showed the region's diverse physiography and climatology resulted in a relatively predictable pattern of change: northern mainland and steeper, snow-fed mountainous watersheds exhibited the greatest increases in discharge, an earlier spring melt, and a transition into rain-fed hydrologic patterns. Predicted streamflow increases for all watersheds ranged from approximately 1-fold to 3-fold for the spawning and incubation period, with increased peak flows in the spring and fall. The hydroclimatic sensitivity index was then combined with an index of currently mapped salmon habitat and species diversity to develop a research and conservation priority matrix, highlighting potentially vulnerable to resilient high-value watersheds. The resulting matrix and observed trends are put forth as a framework to prioritize long-term monitoring plans, mitigation experiments, and finer

  7. Climate Change Sensitivity Index for Pacific Salmon Habitat in Southeast Alaska

    PubMed Central

    Shanley, Colin S.; Albert, David M.

    2014-01-01

    Global climate change may become one of the most pressing challenges to Pacific Salmon conservation and management for southeast Alaska in the 21st Century. Predicted hydrologic change associated with climate change will likely challenge the ability of specific stocks to adapt to new flow regimes and resulting shifts in spawning and rearing habitats. Current research suggests egg-to-fry survival may be one of the most important freshwater limiting factors in Pacific Salmon's northern range due to more frequent flooding events predicted to scour eggs from mobile spawning substrates. A watershed-scale hydroclimatic sensitivity index was developed to map this hypothesis with an historical stream gauge station dataset and monthly multiple regression-based discharge models. The relative change from present to future watershed conditions predicted for the spawning and incubation period (September to March) was quantified using an ensemble global climate model average (ECHAM5, HadCM3, and CGCM3.1) and three global greenhouse gas emission scenarios (B1, A1B, and A2) projected to the year 2080. The models showed the region's diverse physiography and climatology resulted in a relatively predictable pattern of change: northern mainland and steeper, snow-fed mountainous watersheds exhibited the greatest increases in discharge, an earlier spring melt, and a transition into rain-fed hydrologic patterns. Predicted streamflow increases for all watersheds ranged from approximately 1-fold to 3-fold for the spawning and incubation period, with increased peak flows in the spring and fall. The hydroclimatic sensitivity index was then combined with an index of currently mapped salmon habitat and species diversity to develop a research and conservation priority matrix, highlighting potentially vulnerable to resilient high-value watersheds. The resulting matrix and observed trends are put forth as a framework to prioritize long-term monitoring plans, mitigation experiments, and finer

  8. Strontium isotopes delineate fine-scale natal origins and migration histories of Pacific salmon

    USGS Publications Warehouse

    Brennan, Sean R.; Zimmerman, Christian E.; Fernandez, Diego P.; Cerling, Thure E.; McPhee, Megan V.; Wooller, Matthew J.

    2015-01-01

    Highly migratory organisms present major challenges to conservation efforts. This is especially true for exploited anadromous fish species, which exhibit long-range dispersals from natal sites, complex population structures, and extensive mixing of distinct populations during exploitation. By tracing the migratory histories of individual Chinook salmon caught in fisheries using strontium isotopes, we determined the relative production of natal habitats at fine spatial scales and different life histories. Although strontium isotopes have been widely used in provenance research, we present a new robust framework to simultaneously assess natal sources and migrations of individuals within fishery harvests through time. Our results pave the way for investigating how fine-scale habitat production and life histories of salmon respond to perturbations—providing crucial insights for conservation.

  9. Strontium isotopes delineate fine-scale natal origins and migration histories of Pacific salmon.

    PubMed

    Brennan, Sean R; Zimmerman, Christian E; Fernandez, Diego P; Cerling, Thure E; McPhee, Megan V; Wooller, Matthew J

    2015-05-01

    Highly migratory organisms present major challenges to conservation efforts. This is especially true for exploited anadromous fish species, which exhibit long-range dispersals from natal sites, complex population structures, and extensive mixing of distinct populations during exploitation. By tracing the migratory histories of individual Chinook salmon caught in fisheries using strontium isotopes, we determined the relative production of natal habitats at fine spatial scales and different life histories. Although strontium isotopes have been widely used in provenance research, we present a new robust framework to simultaneously assess natal sources and migrations of individuals within fishery harvests through time. Our results pave the way for investigating how fine-scale habitat production and life histories of salmon respond to perturbations-providing crucial insights for conservation. PMID:26601173

  10. Strontium isotopes delineate fine-scale natal origins and migration histories of Pacific salmon

    PubMed Central

    Brennan, Sean R.; Zimmerman, Christian E.; Fernandez, Diego P.; Cerling, Thure E.; McPhee, Megan V.; Wooller, Matthew J.

    2015-01-01

    Highly migratory organisms present major challenges to conservation efforts. This is especially true for exploited anadromous fish species, which exhibit long-range dispersals from natal sites, complex population structures, and extensive mixing of distinct populations during exploitation. By tracing the migratory histories of individual Chinook salmon caught in fisheries using strontium isotopes, we determined the relative production of natal habitats at fine spatial scales and different life histories. Although strontium isotopes have been widely used in provenance research, we present a new robust framework to simultaneously assess natal sources and migrations of individuals within fishery harvests through time. Our results pave the way for investigating how fine-scale habitat production and life histories of salmon respond to perturbations—providing crucial insights for conservation. PMID:26601173

  11. Climate and ecosystem linkages explain widespread declines in North American Atlantic salmon populations.

    PubMed

    Mills, Katherine E; Pershing, Andrew J; Sheehan, Timothy F; Mountain, David

    2013-10-01

    North American Atlantic salmon (Salmo salar) populations experienced substantial declines in the early 1990s, and many populations have persisted at low abundances in recent years. Abundance and productivity declined in a coherent manner across major regions of North America, and this coherence points toward a potential shift in marine survivorship, rather than local, river-specific factors. The major declines in Atlantic salmon populations occurred against a backdrop of physical and biological shifts in Northwest Atlantic ecosystems. Analyses of changes in climate, physical, and lower trophic level biological factors provide substantial evidence that climate conditions directly and indirectly influence the abundance and productivity of North American Atlantic salmon populations. A major decline in salmon abundance after 1990 was preceded by a series of changes across multiple levels of the ecosystem, and a subsequent population change in 1997, primarily related to salmon productivity, followed an unusually low NAO event. Pairwise correlations further demonstrate that climate and physical conditions are associated with changes in plankton communities and prey availability, which are ultimately linked to Atlantic salmon populations. Results suggest that poor trophic conditions, likely due to climate-driven environmental factors, and warmer ocean temperatures throughout their marine habitat area are constraining the productivity and recovery of North American Atlantic salmon populations.

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

    SciTech Connect

    Berejikian, Barry A.

    2004-01-01

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

  13. Human influence on the spatial structure of threatened Pacific salmon metapopulations.

    PubMed

    Fullerton, Aimee H; Lindley, Steven T; Pess, George R; Feist, Blake E; Steel, E Ashley; McElhany, Paul

    2011-10-01

    To remain viable, populations must be resilient to both natural and human-caused environmental changes. We evaluated anthropogenic effects on spatial connections among populations of Chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) (designated as threatened under the U.S. Endangered Species Act) in the lower Columbia and Willamette rivers. For several anthropogenic-effects scenarios, we used graph theory to characterize the spatial relation among populations. We plotted variance in population size against connectivity among populations. In our scenarios, reduced habitat quality decreased the size of populations and hydropower dams on rivers led to the extirpation of several populations, both of which decreased connectivity. Operation of fish hatcheries increased connectivity among populations and led to patchy or panmictic populations. On the basis of our results, we believe recolonization of the upper Cowlitz River by fall and spring Chinook and winter steelhead would best restore metapopulation structure to near-historical conditions. Extant populations that would best conserve connectivity would be those inhabiting the Molalla (spring Chinook), lower Cowlitz, or Clackamas (fall Chinook) rivers and the south Santiam (winter steelhead) and north fork Lewis rivers (summer steelhead). Populations in these rivers were putative sources; however, they were not always the most abundant or centrally located populations. This result would not have been obvious if we had not considered relations among populations in a metapopulation context. Our results suggest that dispersal rate strongly controls interactions among the populations that comprise salmon metapopulations. Thus, monitoring efforts could lead to understanding of the true rates at which wild and hatchery fish disperse. Our application of graph theory allowed us to visualize how metapopulation structure might respond to human activity. The method could be easily extended to evaluations of

  14. FastStats: Health of Asian or Pacific Islander Population

    MedlinePlus

    ... Submit Button NCHS Home Health of Asian or Pacific Islander Population Recommend on Facebook Tweet Share Compartir ... for the U.S. Live births for Asian or Pacific Islander population Number of births: 282,723 Births ...

  15. Modeling the potential impacts of climate change on Pacific salmon culture programs: an example at Winthrop National Fish Hatchery.

    PubMed

    Hanson, Kyle C; Peterson, Douglas P

    2014-09-01

    Hatcheries have long been used in an attempt to mitigate for declines in wild stocks of Pacific salmon (Oncorhynchus spp.), though the conservation benefit of hatcheries is a topic of ongoing debate. Irrespective of conservation benefits, a fundamental question is whether hatcheries will be able to function as they have in the past given anticipated future climate conditions. To begin to answer this question, we developed a deterministic modeling framework to evaluate how climate change may affect hatcheries that rear Pacific salmon. The framework considers the physiological tolerances for each species, incorporates a temperature-driven growth model, and uses two metrics commonly monitored by hatchery managers to determine the impacts of changes in water temperature and availability on hatchery rearing conditions. As a case study, we applied the model to the US Fish and Wildlife Service's Winthrop National Fish Hatchery. We projected that hatchery environmental conditions remained within the general physiological tolerances for Chinook salmon in the 2040s (assuming A1B greenhouse gas emissions scenario), but that warmer water temperatures in summer accelerated juvenile salmon growth. Increased growth during summer coincided with periods when water availability should also be lower, thus increasing the likelihood of physiological stress in juvenile salmon. The identification of these climate sensitivities led to a consideration of potential mitigation strategies such as chilling water, altering rations, or modifying rearing cycles. The framework can be refined with new information, but in its present form, it provides a consistent, repeatable method to assess the vulnerability of hatcheries to predicted climate change.

  16. Modeling the Potential Impacts of Climate Change on Pacific Salmon Culture Programs: An Example at Winthrop National Fish Hatchery

    NASA Astrophysics Data System (ADS)

    Hanson, Kyle C.; Peterson, Douglas P.

    2014-09-01

    Hatcheries have long been used in an attempt to mitigate for declines in wild stocks of Pacific salmon ( Oncorhynchus spp.), though the conservation benefit of hatcheries is a topic of ongoing debate. Irrespective of conservation benefits, a fundamental question is whether hatcheries will be able to function as they have in the past given anticipated future climate conditions. To begin to answer this question, we developed a deterministic modeling framework to evaluate how climate change may affect hatcheries that rear Pacific salmon. The framework considers the physiological tolerances for each species, incorporates a temperature-driven growth model, and uses two metrics commonly monitored by hatchery managers to determine the impacts of changes in water temperature and availability on hatchery rearing conditions. As a case study, we applied the model to the US Fish and Wildlife Service's Winthrop National Fish Hatchery. We projected that hatchery environmental conditions remained within the general physiological tolerances for Chinook salmon in the 2040s (assuming A1B greenhouse gas emissions scenario), but that warmer water temperatures in summer accelerated juvenile salmon growth. Increased growth during summer coincided with periods when water availability should also be lower, thus increasing the likelihood of physiological stress in juvenile salmon. The identification of these climate sensitivities led to a consideration of potential mitigation strategies such as chilling water, altering rations, or modifying rearing cycles. The framework can be refined with new information, but in its present form, it provides a consistent, repeatable method to assess the vulnerability of hatcheries to predicted climate change.

  17. The influence of hydrology and waterway distance on population structure of Chinook salmon Oncorhynchus tshawytscha in a large river.

    PubMed

    Olsen, J B; Beacham, T D; Wetklo, M; Seeb, L W; Smith, C T; Flannery, B G; Wenburg, J K

    2010-04-01

    Adult Chinook salmon Oncorhynchus tshawytscha navigate in river systems using olfactory cues that may be influenced by hydrologic factors such as flow and the number, size and spatial distribution of tributaries. Thus, river hydrology may influence both homing success and the level of straying (gene flow), which in turn influences population structure. In this study, two methods of multivariate analysis were used to examine the extent to which four indicators of hydrology and waterway distance explained population structure of O. tshawytscha in the Yukon River. A partial Mantel test showed that the indicators of hydrology were positively associated with broad-scale (Yukon basin) population structure, when controlling for the influence of waterway distance. Multivariate multiple regression showed that waterway distance, supplemented with the number and flow of major drainage basins, explained more variation in broad-scale population structure than any single indicator. At an intermediate spatial scale, indicators of hydrology did not appear to influence population structure after accounting for waterway distance. These results suggest that habitat changes in the Yukon River, which alter hydrology, may influence the basin-wide pattern of population structure in O. tshawytscha. Further research is warranted on the role of hydrology in concert with waterway distance in influencing population structure in Pacific salmon.

  18. Calibrating acoustic acceleration transmitters for estimating energy use by wild adult Pacific salmon.

    PubMed

    Wilson, S M; Hinch, S G; Eliason, E J; Farrell, A P; Cooke, S J

    2013-03-01

    This study is the first to calibrate acceleration transmitters with energy expenditure using a vertebrate model species. We quantified the relationship between acoustic accelerometer output and oxygen consumption across a range of swim speeds and water temperatures for Harrison River adult sockeye salmon (Oncorhynchus nerka). First, we verified that acceleration transmitters with a sampling frequency of 10 Hz could be used as a proxy for movement in sockeye salmon. Using a mixed effects model, we determined that tailbeat frequency and acceleration were positively correlated (p<0.0001), independent of tag ID. Acceleration (p<0.0001) was positively related to swim speed while fork length (p=0.051) was negatively related to swim speed. Oxygen consumption and accelerometer output (p<0.0001) had a positive linear relationship and were temperature dependent (p<0.0001). There were no differences in swim performance (F(2,12)=1.023, p=0.820) or oxygen consumption (F(1,12)=0.054, p=0.332) between tagged and untagged individuals. Five tagged fish were released into the Fraser River estuary and manually tracked. Of the five fish, three were successfully tracked for 1h. The above relationships were used to determine that the average swim speed was 1.25±0.03 body lengths s(-1) and cost of transport was 3.39±0.17 mg O(2) kg(-1)min(-1), averaged across the three detected fish. Acceleration transmitters can be effectively used to remotely evaluate fine-scale behavior and estimate energy consumption of adult Pacific salmon throughout their homeward spawning migration. PMID:23247092

  19. Calibrating acoustic acceleration transmitters for estimating energy use by wild adult Pacific salmon.

    PubMed

    Wilson, S M; Hinch, S G; Eliason, E J; Farrell, A P; Cooke, S J

    2013-03-01

    This study is the first to calibrate acceleration transmitters with energy expenditure using a vertebrate model species. We quantified the relationship between acoustic accelerometer output and oxygen consumption across a range of swim speeds and water temperatures for Harrison River adult sockeye salmon (Oncorhynchus nerka). First, we verified that acceleration transmitters with a sampling frequency of 10 Hz could be used as a proxy for movement in sockeye salmon. Using a mixed effects model, we determined that tailbeat frequency and acceleration were positively correlated (p<0.0001), independent of tag ID. Acceleration (p<0.0001) was positively related to swim speed while fork length (p=0.051) was negatively related to swim speed. Oxygen consumption and accelerometer output (p<0.0001) had a positive linear relationship and were temperature dependent (p<0.0001). There were no differences in swim performance (F(2,12)=1.023, p=0.820) or oxygen consumption (F(1,12)=0.054, p=0.332) between tagged and untagged individuals. Five tagged fish were released into the Fraser River estuary and manually tracked. Of the five fish, three were successfully tracked for 1h. The above relationships were used to determine that the average swim speed was 1.25±0.03 body lengths s(-1) and cost of transport was 3.39±0.17 mg O(2) kg(-1)min(-1), averaged across the three detected fish. Acceleration transmitters can be effectively used to remotely evaluate fine-scale behavior and estimate energy consumption of adult Pacific salmon throughout their homeward spawning migration.

  20. Evaluation of the Contribution of Fall Chinook Salmon Reared at Columbia River Hatcheries to the Pacific Salmon Fisheries, 1989 Final Report.

    SciTech Connect

    Vreeland, Robert R.

    1989-10-01

    In 1979 this study was initiated to determine the distribution, contribution, and value of artificially propagated fall chinook salmon from the Columbia River. Coded wire tagging (CWT) of hatchery fall chinook salmon began in 1979 with the 1978 brood and was completed in 1982 with the 1981 brood of fish at rearing facilities on the Columbia River system. From 18 to 20 rearing facilities were involved in the study each brood year. Nearly 14 million tagged fish, about 4% of the production, were released as part of this study over the four years, 1979 through 1982. Sampling for recoveries of these tagged fish occurred from 1980 through 1986 in the sport and commercial marine fisheries from Alaska through California, Columbia River fisheries, and returns to hatcheries and adjacent streams. The National Marine Fisheries Service coordinated this study among three fishery agencies: US Fish and Wildfire Service, Oregon Department of Fish and Wildlife, and Washington Department of Fisheries. The objectives of this study were to determine the distribution, fishery contribution, survival, and value of the production of fall chinook salmon from each rearing facility on the Columbia River system to Pacific coast salmon fisheries. To achieve these objectives fish from each hatchery were given a distinctive CWT. 81 refs., 20 figs., 68 tabs.

  1. Lifetime success and interactions of farm salmon invading a native population.

    PubMed Central

    Fleming, I A; Hindar, K; Mjølnerød, I B; Jonsson, B; Balstad, T; Lamberg, A

    2000-01-01

    Farm Atlantic salmon escape and invade rivers throughout the North Atlantic annually, which has generated growing concern about their impacts on native salmon populations. A large-scale experiment was therefore undertaken in order to quantify the lifetime success and interactions of farm salmon invading a Norwegian river. Sexually mature farm and native salmon were genetically screened, radio tagged and released into the River Imsa where no other salmon had been allowed to ascend. The farm fishes were competitively and reproductively inferior, achieving less than one-third the breeding success of the native fishes. Moreover, this inferiority was sex biased, being more pronounced in farm males than females, resulting in the principal route of gene flow involving native males mating with farm females. There were also indications of selection against farm genotypes during early survival but not thereafter. However, evidence of resource competition and competitive displacement existed as the productivity of the native population was depressed by more than 30%. Ultimately, the lifetime reproductive success (adult to adult) of the farm fishes was 16% that of the native salmon. Our results indicate that such annual invasions have the potential for impacting on population productivity, disrupting local adaptations and reducing the genetic diversity of wild salmon populations. PMID:11007327

  2. Titre distribution patterns of infectious haematopoietic necrosis virus in ovarian fluids of hatchery and feral salmon populations

    USGS Publications Warehouse

    Mulcahy, D.; Pascho, R.J.; Jenes, C.K.

    1983-01-01

    Infectious haematopoietic mecrosis virus (IHNV) is enzootic in virtually all populations of sockeye salmon, Oncorhynchus nerka (Walbaum), and in populations of chinook salmon, O. 1shawytscha (Walbaum), of the Sacramento River drainage in California. This disease is an obstacle in hatcheries using brood stocks from these populations. However, naturally spawning sockeye salmon are highly successful and are the most important commercially fished salmon species in the United States. Most of the commercial landings of sockeye salmon are of feral fish originating in Alaska. The success of natural populations of salmon in which IHNV is enzootic, and the recurrent outbreaks of the disease in hatchery fish, led us to compare IHNW prevalence rates in hatchery and feral salmon populations.

  3. Application of Diversity Indices to Quantify Early Life-History Diversity for Chinook Salmon

    SciTech Connect

    Johnson, Gary E.; Sather, Nichole K.; Skalski, John R.; Teel, David

    2014-03-01

    We developed an index of early life history diversity (ELHD) for Pacific salmon (Oncorhynchus spp.) Early life history diversity is the variation in morphological and behavioral traits expressed within and among populations by individual juvenile salmon during their downstream migration. A standard quantitative method does not exist for this prominent concept in salmon biology.

  4. Supplementing long-chain n-3 polyunsaturated fatty acids in canned wild Pacific pink salmon with Alaska salmon oil

    PubMed Central

    Lapis, Trina J; Oliveira, Alexandra C M; Crapo, Charles A; Himelbloom, Brian; Bechtel, Peter J; Long, Kristy A

    2013-01-01

    Establishing n-3 polyunsaturated fatty acid contents in canned wild Alaska pink salmon products is challenging due to ample natural variation found in lipid content of pink salmon muscle. This study investigated the effect of adding salmon oil (SO) to canned pink salmon produced from fish exhibiting two opposite degrees of skin watermarking, bright (B) and dark (D). Specific goals of the study were to evaluate the benefits of adding SO to canned pink salmon with regard to nutritional value of the product, sensory characteristics, and the oxidative and hydrolytic stability of the lipids over thermal processing. Six groups of canned pink salmon were produced with variable levels of SO, either using bright (with 0, 1, or 2% SO) or dark (with 0, 2, or 4% SO) pink salmon. Compositional analysis revealed highest (P < 0.05) lipid content in sample B2 (8.7%) and lowest (P < 0.05) lipid content in sample D0 (3.5%). Lipid content of samples B0, B1, D2, and D4 was not significantly different (P > 0.05) ranging from 5.7% to 6.8%. Consequently, addition of SO to canned pink salmon allowed for consistent lipid content between bright and dark fish. Addition of 1% or 2% SO to canned bright pink salmon was not detrimental to the sensory properties of the product. It is recommended that canned bright pink salmon be supplemented with at least 1% SO, while supplementation with 2% SO would guarantee a minimum quantity of 1.9 g of n-3 fatty acids per 100 g of product. Addition of 4% SO to canned dark pink salmon was detrimental to product texture and taste, while supplementation with 2% SO did not negatively affect sensorial properties of the product. Accordingly, canned dark pink salmon should be supplemented with 2% SO so that a minimum n-3 fatty acids content of 1.5 g per 100 g of product. PMID:24804010

  5. Predation on juvenile pacific salmon oncorhynchus spp. in downstream migrant traps in prairie creek, california

    USGS Publications Warehouse

    Duffy, W.G.; Bjorkstedt, E.P.; Ellings, C.S.

    2011-01-01

    Downstream migrant traps are a widely applied fishery management tool for sampling anadromous Pacific salmon Oncorhynchus spp. and steelhead O. mykiss smolts along theWest Coast of North America and elsewhere, yet predation on juvenile salmonids in traps has not been studied quantitatively.We assessed the frequency of occurrence and abundance of juvenile salmonids in the stomachs of coastal cutthroat trout O. clarkii clarkii, coho salmon O. kisutch, steelhead, and prickly sculpin Cottus asper (>70 mm fork length) captured in traps and in nearby stream habitats. All four predator species took juvenile salmonids with much greater frequency in traps than in stream habitats. Among free-swimming predators, only coastal cutthroat trout were observed with salmonid fry in their stomachs, but they took fewer salmonid prey and appeared to rely more heavily on insect prey than did coastal cutthroat trout captured in traps. Predators consumed up to 25% of the available prey over a broad range of prey abundances. Over the course of the study, predators consumed 2.5% of all salmonid fry captured in traps, but this fraction ranged from less than 1% to more than 10% in any given year. The number of prey taken in traps increased with predator length and with prey abundance in traps, and predation in traps peaked during the period of most intense downstream migration by salmon fry. In contrast, live-box design and trap location had little or no effect on the total number of prey taken by individual predators.We estimated that the predation mortality of juvenile salmon increased by 0.5-1.0% due to in-trap predation (i.e., a 9-10% relative increase over natural predation rates). We found no evidence that predators selected for prey on the basis of species. These results should motivate additional research on methods that reduce or eliminate predation in trap live-boxes and protocols for efficiently measuring predation associated with the trapping of downstream migrants. ?? American

  6. The response of stream periphyton to Pacific salmon: using a model to understand the role of environmental context

    USGS Publications Warehouse

    Bellmore, J. Ryan; Fremier, Alexander K.; Mejia, Francine; Newsom, Michael

    2014-01-01

    1. In stream ecosystems, Pacific salmon deliver subsidies of marine-derived nutrients and disturb the stream bed during spawning. The net effect of this nutrient subsidy and physical disturbance on biological communities can be hard to predict and is likely to be mediated by environmental conditions. For periphyton, empirical studies have revealed that the magnitude and direction of the response to salmon varies from one location to the next. Salmon appear to increase periphyton biomass and/or production in some contexts (a positive response), but decrease them in others (a negative response). 2. To reconcile these seemingly conflicting results, we constructed a system dynamics model that links periphyton biomass and production to salmon spawning. We used this model to explore how environmental conditions influence the periphyton response to salmon. 3. Our simulations suggest that the periphyton response to salmon is strongly mediated by both background nutrient concentrations and the proportion of the stream bed suitable for spawning. Positive periphyton responses occurred when both background nutrient concentrations were low (nutrient limiting conditions) and when little of the stream bed was suitable for spawning (because the substratum is too coarse). In contrast, negative responses occurred when nutrient concentrations were higher or a larger proportion of the bed was suitable for spawning. 4. Although periphyton biomass generally remained above or below background conditions for several months following spawning, periphyton production returned quickly to background values shortly afterwards. As a result, based upon our simulations, salmon did not greatly increase or decrease overall annual periphyton production. This suggests that any increase in production by fish or invertebrates in response to returning salmon is more likely to occur via direct consumption of salmon carcasses and/or eggs, rather than the indirect effects of greater periphyton production. 5

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

    PubMed

    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. PMID:25753912

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

    PubMed

    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.

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

    USGS Publications Warehouse

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

    2004-01-01

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

  10. Recent physical connections may explain weak genetic structure in western Alaskan chum salmon (Oncorhynchus keta) populations

    PubMed Central

    Garvin, Michael R; Kondzela, Christine M; Martin, Patrick C; Finney, Bruce; Guyon, Jeffrey; Templin, William D; DeCovich, Nick; Gilk-Baumer, Sara; Gharrett, Anthony J

    2013-01-01

    Low genetic divergence at neutral loci among populations is often the result of high levels of contemporary gene flow. Western Alaskan summer-run chum salmon (Oncorhynchus keta) populations demonstrate weak genetic structure, but invoking contemporary gene flow as the basis for the low divergence is problematic because salmon home to their natal streams and some of the populations are thousands of kilometers apart. We used genotypes from microsatellite and single nucleotide polymorphism loci to investigate alternative explanations for the current genetic structure of chum salmon populations from western Alaska. We also estimated current levels of gene flow among Kuskokwim River populations. Our results suggest that weak genetic structure is best explained by physical connections that occurred after the Holocene Thermal Maximum among the Yukon, Kuskokwim, and Nushagak drainages that allowed gene flow to occur among now distant populations. PMID:23919176

  11. Species and life-history affects the utility of otolith chemical composition to determine natal stream-of-origin in Pacific salmon

    USGS Publications Warehouse

    Zimmerman, Christian E.; Swanson, Heidi K.; Volk, Eric C.; Kent, Adam J.R.

    2013-01-01

    To test the utility of otolith chemical composition as a tool for determining the natal stream of origin for salmon, we examined water chemistry and otoliths of juvenile and adult Chum Salmon Oncorhynchus keta and Coho Salmon O. kisutch from three watersheds (five rivers) in the Norton Sound region of Alaska. The two species are characterized by different life histories: Coho Salmon rear in freshwater for up to 3 years, whereas Chum Salmon emigrate from freshwater shortly after emergence. We used laser ablation (LA) inductively coupled plasma (ICP) mass spectrometry (MS) to quantify element: Ca ratios for Mg, Mn, Zn, Sr, and Ba, and we used multicollector LA-ICP-MS to determine 87Sr:86Sr ratios in otolith regions corresponding to the period of freshwater residence. Significant differences existed in both water and otolith elemental composition, suggesting that otolith composition could be used to discriminate the natal origin of Coho Salmon and Chum Salmon but only when 87Sr:86Sr ratios were included in the discriminant function analyses. The best discriminant model included 87Sr:86Sr ratios, and without 87Sr:86Sr ratios it was difficult to discriminate among watersheds and rivers. Classification accuracy was 80% for Coho Salmon and 68% for Chum Salmon, indicating that this method does not provide sufficient sensitivity to estimate straying rates of Pacific salmon at the scale we studied.

  12. Assessing the relative importance of local and regional processes on the survival of a threatened salmon population.

    PubMed

    Miller, Jessica A; Teel, David J; Peterson, William T; Baptista, Antonio M

    2014-01-01

    Research on regulatory mechanisms in biological populations often focuses on environmental covariates. An integrated approach that combines environmental indices with organismal-level information can provide additional insight on regulatory mechanisms. Survival of spring/summer Snake River Chinook salmon (Oncorhynchus tshawytscha) is consistently low whereas some adjacent populations with similar life histories experience greater survival. It is not known if populations with differential survival respond similarly during early marine residence, a critical period in the life history. Ocean collections, genetic stock identification, and otolith analyses were combined to evaluate the growth-mortality and match-mismatch hypotheses during early marine residence of spring/summer Snake River Chinook salmon. Interannual variation in juvenile attributes, including size at marine entry and marine growth rate, was compared with estimates of survival and physical and biological metrics. Multiple linear regression and multi-model inference were used to evaluate the relative importance of biological and physical metrics in explaining interannual variation in survival. There was relatively weak support for the match-mismatch hypothesis and stronger evidence for the growth-mortality hypothesis. Marine growth and size at capture were strongly, positively related to survival, a finding similar to spring Chinook salmon from the Mid-Upper Columbia River. In hindcast models, basin-scale indices (Pacific Decadal Oscillation (PDO) and the North Pacific Gyre Oscillation (NPGO)) and biological indices (juvenile salmon catch-per-unit-effort (CPUE) and a copepod community index (CCI)) accounted for substantial and similar portions of variation in survival for juvenile emigration years 1998-2008 (R2>0.70). However, in forecast models for emigration years 2009-2011, there was an increasing discrepancy between predictions based on the PDO (50-448% of observed value) compared with those based on

  13. Assessing the relative importance of local and regional processes on the survival of a threatened salmon population.

    PubMed

    Miller, Jessica A; Teel, David J; Peterson, William T; Baptista, Antonio M

    2014-01-01

    Research on regulatory mechanisms in biological populations often focuses on environmental covariates. An integrated approach that combines environmental indices with organismal-level information can provide additional insight on regulatory mechanisms. Survival of spring/summer Snake River Chinook salmon (Oncorhynchus tshawytscha) is consistently low whereas some adjacent populations with similar life histories experience greater survival. It is not known if populations with differential survival respond similarly during early marine residence, a critical period in the life history. Ocean collections, genetic stock identification, and otolith analyses were combined to evaluate the growth-mortality and match-mismatch hypotheses during early marine residence of spring/summer Snake River Chinook salmon. Interannual variation in juvenile attributes, including size at marine entry and marine growth rate, was compared with estimates of survival and physical and biological metrics. Multiple linear regression and multi-model inference were used to evaluate the relative importance of biological and physical metrics in explaining interannual variation in survival. There was relatively weak support for the match-mismatch hypothesis and stronger evidence for the growth-mortality hypothesis. Marine growth and size at capture were strongly, positively related to survival, a finding similar to spring Chinook salmon from the Mid-Upper Columbia River. In hindcast models, basin-scale indices (Pacific Decadal Oscillation (PDO) and the North Pacific Gyre Oscillation (NPGO)) and biological indices (juvenile salmon catch-per-unit-effort (CPUE) and a copepod community index (CCI)) accounted for substantial and similar portions of variation in survival for juvenile emigration years 1998-2008 (R2>0.70). However, in forecast models for emigration years 2009-2011, there was an increasing discrepancy between predictions based on the PDO (50-448% of observed value) compared with those based on

  14. Assessing the Relative Importance of Local and Regional Processes on the Survival of a Threatened Salmon Population

    PubMed Central

    Miller, Jessica A.; Teel, David J.; Peterson, William T.; Baptista, Antonio M.

    2014-01-01

    Research on regulatory mechanisms in biological populations often focuses on environmental covariates. An integrated approach that combines environmental indices with organismal-level information can provide additional insight on regulatory mechanisms. Survival of spring/summer Snake River Chinook salmon (Oncorhynchus tshawytscha) is consistently low whereas some adjacent populations with similar life histories experience greater survival. It is not known if populations with differential survival respond similarly during early marine residence, a critical period in the life history. Ocean collections, genetic stock identification, and otolith analyses were combined to evaluate the growth-mortality and match-mismatch hypotheses during early marine residence of spring/summer Snake River Chinook salmon. Interannual variation in juvenile attributes, including size at marine entry and marine growth rate, was compared with estimates of survival and physical and biological metrics. Multiple linear regression and multi-model inference were used to evaluate the relative importance of biological and physical metrics in explaining interannual variation in survival. There was relatively weak support for the match-mismatch hypothesis and stronger evidence for the growth-mortality hypothesis. Marine growth and size at capture were strongly, positively related to survival, a finding similar to spring Chinook salmon from the Mid-Upper Columbia River. In hindcast models, basin-scale indices (Pacific Decadal Oscillation (PDO) and the North Pacific Gyre Oscillation (NPGO)) and biological indices (juvenile salmon catch-per-unit-effort (CPUE) and a copepod community index (CCI)) accounted for substantial and similar portions of variation in survival for juvenile emigration years 1998–2008 (R2>0.70). However, in forecast models for emigration years 2009–2011, there was an increasing discrepancy between predictions based on the PDO (50–448% of observed value) compared with those

  15. Modeling the potential impacts of climate change on Pacific salmon culture programs: an example at Winthrop National Fish Hatchery.

    PubMed

    Hanson, Kyle C; Peterson, Douglas P

    2014-09-01

    Hatcheries have long been used in an attempt to mitigate for declines in wild stocks of Pacific salmon (Oncorhynchus spp.), though the conservation benefit of hatcheries is a topic of ongoing debate. Irrespective of conservation benefits, a fundamental question is whether hatcheries will be able to function as they have in the past given anticipated future climate conditions. To begin to answer this question, we developed a deterministic modeling framework to evaluate how climate change may affect hatcheries that rear Pacific salmon. The framework considers the physiological tolerances for each species, incorporates a temperature-driven growth model, and uses two metrics commonly monitored by hatchery managers to determine the impacts of changes in water temperature and availability on hatchery rearing conditions. As a case study, we applied the model to the US Fish and Wildlife Service's Winthrop National Fish Hatchery. We projected that hatchery environmental conditions remained within the general physiological tolerances for Chinook salmon in the 2040s (assuming A1B greenhouse gas emissions scenario), but that warmer water temperatures in summer accelerated juvenile salmon growth. Increased growth during summer coincided with periods when water availability should also be lower, thus increasing the likelihood of physiological stress in juvenile salmon. The identification of these climate sensitivities led to a consideration of potential mitigation strategies such as chilling water, altering rations, or modifying rearing cycles. The framework can be refined with new information, but in its present form, it provides a consistent, repeatable method to assess the vulnerability of hatcheries to predicted climate change. PMID:24993792

  16. Using Phylogenetic Analysis to Detect Market Substitution of Atlantic Salmon for Pacific Salmon: An Introductory Biology Laboratory Experiment

    ERIC Educational Resources Information Center

    Cline, Erica; Gogarten, Jennifer

    2012-01-01

    We describe a laboratory exercise developed for the cell and molecular biology quarter of a year-long majors' undergraduate introductory biology sequence. In an analysis of salmon samples collected by students in their local stores and restaurants, DNA sequencing and phylogenetic analysis were used to detect market substitution of Atlantic salmon…

  17. Modeling the Oxygen Consumption Rates in Pacific Salmon and Steelhead: An Assessment of Current Models and Practices

    SciTech Connect

    Trudel, Marc; Geist, David R.; Welch, David W.

    2004-03-01

    Bioenergetic models of fish have been used to study a large number of processes. Like most models, bioenergetic models require the estimation of numerous parameters. As a consequence, they have often relied on parameters borrowed from other species or values extrapolated from other life stages or size-classes. The magnitude of the biases associated with these practices remains largely unknown. The objective of this study was to determine whether or not metabolic rates could be extrapolated between closely related species and life stages. We focused on Pacific salmon Oncorhynchus spp. and steelhead O. mykiss, as the metabolic rates of these species have been well documented. Our analyses showed that models derived from closely related species did not accurately predict the metabolic rates of salmon, indicating that the practice of "species borrowing" should be avoided in assessing fish metabolic rates. Our work also showed that allometric equations of metabolic rates were not stable when measured over small size ranges and that biases could be introduced when these models are extrapolated to smaller or larger fish. In addition, we found that, except for steelhead, published models of Pacific salmon metabolic rate were inaccurate. Mean bias ranged from close to 0% to over 200% depending on size and water temperature, with about two-thirds of the bias values exceeding 20%. These biases could have large impacts on bioenergetic model predictions. Increased funding and scientific recognition of the need for additional basic research will be necessary to build more accurate bioenergetic models for Pacific salmon, especially models applied to the ocean phase of the life cycle.

  18. Spatio-Temporal Migration Patterns of Pacific Salmon Smolts in Rivers and Coastal Marine Waters

    PubMed Central

    Melnychuk, Michael C.; Welch, David W.; Walters, Carl J.

    2010-01-01

    Background Migrations allow animals to find food resources, rearing habitats, or mates, but often impose considerable predation risk. Several behavioural strategies may reduce this risk, including faster travel speed and taking routes with shorter total distance. Descriptions of the natural range of variation in migration strategies among individuals and populations is necessary before the ecological consequences of such variation can be established. Methodology/Principal Findings Movements of tagged juvenile coho, steelhead, sockeye, and Chinook salmon were quantified using a large-scale acoustic tracking array in southern British Columbia, Canada. Smolts from 13 watersheds (49 watershed/species/year combinations) were tagged between 2004–2008 and combined into a mixed-effects model analysis of travel speed. During the downstream migration, steelhead were slower on average than other species, possibly related to freshwater residualization. During the migration through the Strait of Georgia, coho were slower than steelhead and sockeye, likely related to some degree of inshore summer residency. Hatchery-reared smolts were slower than wild smolts during the downstream migration, but after ocean entry, average speeds were similar. In small rivers, downstream travel speed increased with body length, but in the larger Fraser River and during the coastal migration, average speed was independent of body length. Smolts leaving rivers located towards the northern end of the Strait of Georgia ecosystem migrated strictly northwards after ocean entry, but those from rivers towards the southern end displayed split-route migration patterns within populations, with some moving southward. Conclusions/Significance Our results reveal a tremendous diversity of behavioural migration strategies used by juvenile salmon, across species, rearing histories, and habitats, as well as within individual populations. During the downstream migration, factors that had strong effects on travel

  19. Temperature-associated population diversity in salmon confers benefits to mobile consumers.

    PubMed

    Ruff, Casey P; Schindler, Daniel E; Armstrong, Jonathan B; Bentley, Kale T; Brooks, Gabriel T; Holtgrieve, Gordon W; McGlauflin, Molly T; Torgersen, Christian E; Seeb, James E

    2011-11-01

    Habitat heterogeneity can generate intraspecific diversity through local adaptation of populations. While it is becoming increasingly clear that population diversity can increase stability in species abundance, less is known about how population diversity can benefit consumers that can integrate across population diversity in their prey. Here we demonstrate cascading effects of thermal heterogeneity on trout-salmon interactions in streams where rainbow trout rely heavily on the seasonal availability of anadromous salmon eggs. Water temperature in an Alaskan stream varied spatially from 5 degrees C to 17.5 degrees C, and spawning sockeye salmon showed population differentiation associated with this thermal heterogeneity. Individuals that spawned early in cool regions of the 5 km long stream were genetically differentiated from those spawning in warmer regions later in the season. Sockeye salmon spawning generates a pulsed resource subsidy that supports the majority of seasonal growth in stream-dwelling rainbow trout. The spatial and temporal structuring of sockeye salmon spawn timing in our focal stream extended the duration of the pulsed subsidy compared to a thermally homogeneous stream with a single population of salmon. Further, rainbow trout adopted movement strategies that exploited the multiple pulses of egg subsidies in the thermally heterogeneous stream. Fish that moved to track the resource pulse grew at rates about 2.5 times higher than those that remained stationary or trout in the reference stream with a single seasonal pulse of eggs. Our results demonstrate that habitat heterogeneity can have important effects on the population diversity of dominant species, and in turn, influence their value to species that prey upon them. Therefore, habitat homogenization may have farther-reaching ecological effects than previously considered.

  20. Temperature-associated population diversity in salmon confers benefits to mobile consumers

    USGS Publications Warehouse

    Ruff, Casey P.; Schindle, Daniel E.; Armstrong, Jonathan B.; Bentle, Kale T.; Brooks, Gabriel T.; Holtgrieve, Gordon W.; McGlauflin, Molly T.; Torgersen, Christian E.; Seeb, James E.

    2011-01-01

    Habitat heterogeneity can generate intraspecific diversity through local adaptation of populations. While it is becoming increasingly clear that population diversity can increase stability in species abundance, less is known about how population diversity can benefit consumers that can integrate across population diversity in their prey. Here we demonstrate cascading effects of thermal heterogeneity on trout–salmon interactions in streams where rainbow trout rely heavily on the seasonal availability of anadromous salmon eggs. Water temperature in an Alaskan stream varied spatially from 5°C to 17.5°C, and spawning sockeye salmon showed population differentiation associated with this thermal heterogeneity. Individuals that spawned early in cool regions of the 5 km long stream were genetically differentiated from those spawning in warmer regions later in the season. Sockeye salmon spawning generates a pulsed resource subsidy that supports the majority of seasonal growth in stream-dwelling rainbow trout. The spatial and temporal structuring of sockeye salmon spawn timing in our focal stream extended the duration of the pulsed subsidy compared to a thermally homogeneous stream with a single population of salmon. Further, rainbow trout adopted movement strategies that exploited the multiple pulses of egg subsidies in the thermally heterogeneous stream. Fish that moved to track the resource pulse grew at rates about 2.5 times higher than those that remained stationary or trout in the reference stream with a single seasonal pulse of eggs. Our results demonstrate that habitat heterogeneity can have important effects on the population diversity of dominant species, and in turn, influence their value to species that prey upon them. Therefore, habitat homogenization may have farther-reaching ecological effects than previously considered.

  1. Fitness reduction and potential extinction of wild populations of Atlantic salmon, Salmo salar, as a result of interactions with escaped farm salmon.

    PubMed

    McGinnity, Philip; Prodöhl, Paulo; Ferguson, Andy; Hynes, Rosaleen; Maoiléidigh, Niall O; Baker, Natalie; Cotter, Deirdre; O'Hea, Brendan; Cooke, Declan; Rogan, Ger; Taggart, John; Cross, Tom

    2003-12-01

    The high level of escapes from Atlantic salmon farms, up to two million fishes per year in the North Atlantic, has raised concern about the potential impact on wild populations. We report on a two-generation experiment examining the estimated lifetime successes, relative to wild natives, of farm, F(1) and F(2) hybrids and BC(1) backcrosses to wild and farm salmon. Offspring of farm and "hybrids" (i.e. all F(1), F(2) and BC(1) groups) showed reduced survival compared with wild salmon but grew faster as juveniles and displaced wild parr, which as a group were significantly smaller. Where suitable habitat for these emigrant parr is absent, this competition would result in reduced wild smolt production. In the experimental conditions, where emigrants survived downstream, the relative estimated lifetime success ranged from 2% (farm) to 89% (BC(1) wild) of that of wild salmon, indicating additive genetic variation for survival. Wild salmon primarily returned to fresh water after one sea winter (1SW) but farm and 'hybrids' produced proportionately more 2SW salmon. However, lower overall survival means that this would result in reduced recruitment despite increased 2SW fecundity. We thus demonstrate that interaction of farm with wild salmon results in lowered fitness, with repeated escapes causing cumulative fitness depression and potentially an extinction vortex in vulnerable populations.

  2. Stable isotope analysis of Pacific salmon: insight into trophic status and oceanographic conditions over the last 30 years

    NASA Astrophysics Data System (ADS)

    Satterfield, Franklin R.; Finney, Bruce P.

    Food web interactions and the response of Pacific salmon to physical processes in the North Pacific Ocean over interannual and interdecadal timescales are explored using naturally occurring stable isotope ratios of carbon ( 13C/ 12C) and nitrogen ( 15N/ 14N). Stable isotope analyses of five species of sexually mature North Pacific salmon from Alaska ( Oncorhynchus spp.) cluster into three groups: chinook salmon ( O. tshawytscha) have the highest values, followed by coho ( O. kisutch), with chum ( O. keta), sockeye ( O. nerka), and pink ( O. gorbuscha) together having the lowest values. Although detailed isotopic data on salmon prey are lacking, there are limited data on relevant prey items from areas in which they are found in high abundance. These data suggest that the characteristics of the sockeye, pink and chum we have analyzed are compatible with their diets including open ocean squid and zooplankton, which are in general agreement with stomach content analyses. Isotope relationships between muscle and scale show consistent relationships for both δ13C ( R2=0.98) and δ 15N ( R2=0.90). Thus, scales, which have been routinely archived for many systems, can be used for retrospective analyses. Archived sockeye salmon scales spanning 1966-1999 from Red Lake, Kodiak Island, Alaska were analyzed for their stable isotope ratios of carbon and nitrogen. The δ15N record displays a decreasing trend of ~3‰ from 1969-1982 and an increasing trend of ~3‰ from 1982-1992, while the variations in δ13C are relatively minor. These trends may result from factors such as shifts in trophic level of feeding and/or feeding location, or may originate at the base of the food web via changes in processes such as nutrient cycling or primary productivity. Detailed studies on prey isotopic variability and its controls are needed to distinguish between these factors, and thus to improve the use of stable isotope analysis as a tool to learn more about present and past ecosystem change

  3. Evaluate Factors Limiting Columbia River Gorge Chum Salmon Populations; FY 2002 Annual Report.

    SciTech Connect

    Uusitalo, Nancy M.

    2003-01-30

    Adult and juvenile chum salmon were monitored from October 2001 through September 2002 to evaluate factors limiting production. In 2001, 6 and 69 adult chum salmon were captured in the Hardy Creek and Hamilton Springs weirs, respectively. In 2001, 285 and 328 chum salmon carcasses were recovered during spawning ground surveys in Hardy Creek and Hamilton Springs, respectively. Twenty-eight fish captured in the mainstem Columbia River, Hamilton Springs, and Hardy Creek were implanted with radio tags and tracked via an array of fixed aerial, underwater antennas and a mobile tracking unit. Using the Area-Under-the-Curve program population estimates of adult chum salmon were 835 in Hardy Creek and 617 in Hamilton Springs. Juvenile chum salmon migration was monitored from March-June 2002. Total catches for Hardy Creek and Hamilton Springs were 103,315 and 140,220, respectively. Estimates of juvenile chum salmon emigration were 450,195 ({+-}21,793) in Hardy Creek and 561,462 ({+-}21,423) in Hamilton Springs.

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

    SciTech Connect

    van der Naald, Wayne; Duff, Cameron; Friesen, Thomas A.

    2006-02-01

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

  5. Sequential tests for infectious hematopoietic necrosis virus in individuals and populations of sockeye salmon

    USGS Publications Warehouse

    Mulcahy, D.; Pascho, R.J.

    1986-01-01

    The incidence and titer distribution of infectious hematopoietic necrosis virus in cavity fluid from spent female sockeye salmon (Oncorhynchus nerka) varied little when fish from a naturally spawning population were sampled three times on alternate days. However, when prespawning female sockeye salmon from a second population were individually tagged, penned, and sampled daily, the incidence and proportion of fish with high virus titer rose over a 6-d period. In 10 instances, consecutive cavity fluid samples from the same fish reverted from virus-positive to virus-negative. We suggest that spent fish should be sampled when accurate and quantitative data on the incidence and level of the virus are required.

  6. Maternal and environmental influences on egg size and juvenile life-history traits in Pacific salmon.

    PubMed

    Braun, Douglas C; Patterson, David A; Reynolds, John D

    2013-06-01

    Life-history traits such as fecundity and offspring size are shaped by investment trade-offs faced by mothers and mediated by environmental conditions. We use a 21-year time series for three populations of wild sockeye salmon (Oncorhynchus nerka) to test predictions for such trade-offs and responses to conditions faced by females during migration, and offspring during incubation. In years when their 1100 km upstream migration was challenged by high water discharges, females that reached spawning streams had invested less in gonads by producing smaller but not fewer eggs. These smaller eggs produced lighter juveniles, and this effect was further amplified in years when the incubation water was warm. This latter result suggests that there should be selection for larger eggs to compensate in populations that consistently experience warm incubation temperatures. A comparison among 16 populations, with matching migration and rearing environments but different incubation environments (i.e., separate spawning streams), confirmed this prediction; smaller females produced larger eggs for their size in warmer creeks. Taken together, these results reveal how maternal phenotype and environmental conditions can shape patterns of reproductive investment and consequently juvenile fitness-related traits within and among populations. PMID:23789081

  7. Climate change, pink salmon, and the nexus between bottom-up and top-down forcing in the subarctic Pacific Ocean and Bering Sea

    PubMed Central

    Springer, Alan M.; van Vliet, Gus B.

    2014-01-01

    Climate change in the last century was associated with spectacular growth of many wild Pacific salmon stocks in the North Pacific Ocean and Bering Sea, apparently through bottom-up forcing linking meteorology to ocean physics, water temperature, and plankton production. One species in particular, pink salmon, became so numerous by the 1990s that they began to dominate other species of salmon for prey resources and to exert top-down control in the open ocean ecosystem. Information from long-term monitoring of seabirds in the Aleutian Islands and Bering Sea reveals that the sphere of influence of pink salmon is much larger than previously known. Seabirds, pink salmon, other species of salmon, and by extension other higher-order predators, are tightly linked ecologically and must be included in international management and conservation policies for sustaining all species that compete for common, finite resource pools. These data further emphasize that the unique 2-y cycle in abundance of pink salmon drives interannual shifts between two alternate states of a complex marine ecosystem. PMID:24706809

  8. Climate change, pink salmon, and the nexus between bottom-up and top-down forcing in the subarctic Pacific Ocean and Bering Sea.

    PubMed

    Springer, Alan M; van Vliet, Gus B

    2014-05-01

    Climate change in the last century was associated with spectacular growth of many wild Pacific salmon stocks in the North Pacific Ocean and Bering Sea, apparently through bottom-up forcing linking meteorology to ocean physics, water temperature, and plankton production. One species in particular, pink salmon, became so numerous by the 1990s that they began to dominate other species of salmon for prey resources and to exert top-down control in the open ocean ecosystem. Information from long-term monitoring of seabirds in the Aleutian Islands and Bering Sea reveals that the sphere of influence of pink salmon is much larger than previously known. Seabirds, pink salmon, other species of salmon, and by extension other higher-order predators, are tightly linked ecologically and must be included in international management and conservation policies for sustaining all species that compete for common, finite resource pools. These data further emphasize that the unique 2-y cycle in abundance of pink salmon drives interannual shifts between two alternate states of a complex marine ecosystem.

  9. Verification of SNPs Associated with Growth Traits in Two Populations of Farmed Atlantic Salmon

    PubMed Central

    Tsai, Hsin Y.; Hamilton, Alastair; Guy, Derrick R.; Tinch, Alan E.; Bishop, Steve C.; Houston, Ross D.

    2015-01-01

    Understanding the relationship between genetic variants and traits of economic importance in aquaculture species is pertinent to selective breeding programmes. High-throughput sequencing technologies have enabled the discovery of large numbers of SNPs in Atlantic salmon, and high density SNP arrays now exist. A previous genome-wide association study (GWAS) using a high density SNP array (132K SNPs) has revealed the polygenic nature of early growth traits in salmon, but has also identified candidate SNPs showing suggestive associations with these traits. The aim of this study was to test the association of the candidate growth-associated SNPs in a separate population of farmed Atlantic salmon to verify their effects. Identifying SNP-trait associations in two populations provides evidence that the associations are true and robust. Using a large cohort (N = 1152), we successfully genotyped eight candidate SNPs from the previous GWAS, two of which were significantly associated with several growth and fillet traits measured at harvest. The genes proximal to these SNPs were identified by alignment to the salmon reference genome and are discussed in the context of their potential role in underpinning genetic variation in salmon growth. PMID:26703584

  10. Interannual variability in stock abundance and body size of Pacific salmon in the central Bering Sea

    NASA Astrophysics Data System (ADS)

    Ishida, Y.; Azumaya, T.; Fukuwaka, M.; Davis, N.

    2002-10-01

    Variability in catch-per-unit-effort (CPUE) and mean body size was examined for pink, chum and sockeye salmon collected with research gillnets in the central Bering Sea in July from 1972 to 2000. The CPUEs for all three species showed significant increasing trends, but with large interannual variability. The CPUE of pink salmon was higher in odd years than in even years, and abruptly increased in the odd years post-1989. Chum salmon also showed odd/even year fluctuations, which were out-of-phase with those of pink salmon. Sockeye salmon showed no biennial such fluctuations. The CPUEs of chum and sockeye salmon were higher during 1979-1984 and 1992-1998, but lower during 1985-1991, especially for younger age group such as ocean age 2 and 3. Data for sea surface temperature (SST) and abundances of chum and sockeye salmon during four periods (1972-1976, 1977-1984, 1985-1990, and 1991-2000) indicated a portion of chum and sockeye salmon were distributed in the northern Gulf of Alaska in 1985-1990, when SST in the Gulf of Alaska was low. However, the fish were more abundant in the Bering Sea in 1977-1984 and 1991-2000 when SST was relatively high in the Gulf of Alaska. Body size of pink salmon showed a significant decreasing trend. Chum and sockeye salmon also showed significant decreasing trends in body size at ocean age 3 and older ages, but not at ocean age 2. Significant negative relationships between CPUE and body size were found within species. No significant correlations were found between an Aleutian low pressure index (ALPI) with CPUE and body size, but the increases in CPUE around the late 1970s and early 1990s may be partly be the result of shifts in the distributions of chum and sockeye salmon caused by SST changes related to the regime shift in 1977 and 1989 identified by the ALPI.

  11. The Riverscape Analysis Project: Using Remote Sensing to Leverage Salmon Science and Management Applications Around the Pacific Rim

    NASA Astrophysics Data System (ADS)

    Chilcote, S.; Maumenee, N.; Lucotch, J.; Whited, D.; Bansack, T.; Kimball, J. S.; Stanford, J.

    2009-12-01

    The Salmonid Rivers Observatory Network (SaRON) is an intensive field research project which aims to describe the relation between salmon productivion and diversity in relation to environmental drivers and physical complexity of riverine shifting habitat mosaics. The Riverscape Analysis Project (RAP) is a spatially explicit remote sensing database which quantifies and ranks different combinations of physical landscape metrics around the Pacific Rim, displaying results through a publically accessible web based decision support framework designed to empower regional management and conservation efforts for wild salmon. The objective of our research is to explicitly describe and relate different habitat types and their potential fish production at a variety of scales and throughout the range of Pacific salmon, leveraging our field research through available satellite remote sensing and geospatial analysis. We find that rivers exhibit a range of physical, chemical, and biotic conditions consistent with the shifting habitat mosaic (SHM) concept. Landscape physical variables derived from global Landsat imagery and SRTM-DEM information explain 93.2% of observed variability in over 1500 watersheds across the Pacific Rim. We expect that it is these coarse scale differences in river typologies which are responsible for the fine scale differences in habitat conditions and juvenile salmon production. Therefore, we ranked rivers using landscape scale physical variables to prioritize them for management actions based on potential productivity. For example, the Kvichak River of Bristol Bay is highly ranked, 8th, based on its physical landscape structure as well as current human impacts. Currently, the Bristol Bay fishery is extremely productive. Habitat structure can be used not only to define reference conditions and management targets for how many fish we would expect a river to produce based on its potential habitat capacity, but it also provides new analytical tools to

  12. 50 CFR Table 1 to Subpart H of... - Pacific Salmon EFH Identified by USGS Hydrologic Unit Code (HUC)

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... salmon n/a 17110010 WA Snoqualmie Chinook, coho, and pink salmon Tolt Dam (S. Fork Tolt R.) 17110011 WA... salmon n/a 17080006 OR/WA Lower Columbia Chinook and coho salmon n/a 17090001 OR Middle Fork Willamette River Chinook salmon Dexter Dam 17090002 OR Coast Fork Willamette River Chinook salmon Dorena...

  13. Footprints of Directional Selection in Wild Atlantic Salmon Populations: Evidence for Parasite-Driven Evolution?

    PubMed Central

    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. PMID

  14. RESTORING WILD SALMON TO THE PACIFIC NORTHWEST: FRAMING THE RISK QUESTION

    EPA Science Inventory

    In western North America, it is urgent to assess accurately the various options proposed to protect or restore wild salmon. For the past 125 years, a variety of analytic approaches have been employed to assess the ecological consequences of salmon management options. Each appro...

  15. Classification of physical habitat for Pacific Salmon in a Semi-Arid Basin in Northeast Oregon

    NASA Astrophysics Data System (ADS)

    O'Daniel, S. J.; Webster, J.; Lambert, M.

    2010-12-01

    Currently, significant efforts are aimed at improving freshwater habitats that Pacific Salmon require for spawning and rearing. In order to inform fisheries management, we developed models based hydrologic and geomorphic variables that influences channel morphology across the Umatilla watershed in northeast Oregon. We calculate several DEM derived parameters include, channel slope, SD channel slope, base flow, sinuosity, floodplain width, valley slope, wavelength of the channel belt and the ratio of channel segment length to floodplain width. These parameters were used to produce both standard and statistically derived stream classifications. To estimate bed grain size, we used slope and cumulative drainage area measurements from 10 meter DEMs to solve the Shields equation (Buffington et al. 2004). We created both Montgomery and Buffington classifications (1997) and a statistical classifications using K-means clustering and fuzzy sets. Using parameters developed for the stream classification, we compare target segments to similar segments using a probability distribution. Models include CART and neural networks, that were evaluated, to predict spawning areas (redds) for Oncorhynchus mykiss (Summer Steelhead) and Oncorhynchus tshawytscha (Spring Chinook). Prediction of redds using classification and regression trees, with resampling, produce an R^2 of .68 for Summer Steelhead and an R^2 of .79 for Spring Chinook. Additionally, these results suggest that the sum segment length of Summer Steelhead redds distribution may increase from 1.3% (currently measured amount) to 4.2% (predicted potential) of the network. Outputs from the Spring Chinook model suggests a redds distribution change from 1.9% (currently measured amount) to 3.7% predicted potential) across the watershed. We used widely available spatial datasets to apply models over large areas to produce rapid, comparable stream habitat assessments.

  16. Climate change and potential impacts on bristol bay sockeye salmon populations

    EPA Science Inventory

    Scientific research has shown that climate change has already caused detectable changes to ecosystems throughout Alaska. As warming is predicted to continue, it is likely to lead to changes in marine and freshwater aquatic ecosystems and impact sockeye salmon populations in Brist...

  17. Cessation of a salmon decline with control of parasites.

    PubMed

    Peacock, Stephanie J; Krkosek, Martin; Proboszcz, Stan; Orr, Craig; Lewis, Mark A

    2013-04-01

    The resilience of coastal social-ecological systems may depend on adaptive responses to aquaculture disease outbreaks that can threaten wild and farm fish. A nine-year study of parasitic sea lice (Lepeophtheirus salmonis) and pink salmon (Oncorhynchus gorbuscha) from Pacific Canada indicates that adaptive changes in parasite management on salmon farms have yielded positive conservation outcomes. After four years of sea lice epizootics and wild salmon population decline, parasiticide application on salmon farms was adapted to the timing of wild salmon migrations. Winter treatment of farm fish with parasiticides, prior to the out-migration of wild juvenile salmon, has reduced epizootics of wild salmon without significantly increasing the annual number of treatments. Levels of parasites on wild juvenile salmon significantly influence the growth rate of affected salmon populations, suggesting that these changes in management have had positive outcomes for wild salmon populations. These adaptive changes have not occurred through formal adaptive management, but rather, through multi-stakeholder processes arising from a contentious scientific and public debate. Despite the apparent success of parasite control on salmon farms in the study region, there remain concerns about the long-term sustainability of this approach because of the unknown ecological effects of parasticides and the potential for parasite resistance to chemical treatments.

  18. A Metabolomic Approach To Detect Effects of Salmon Farming on Wild Saithe (Pollachius virens) Populations.

    PubMed

    Maruhenda Egea, Frutos C; Toledo-Guedes, Kilian; Sanchez-Jerez, Pablo; Ibanco-Cañete, Ricardo; Uglem, Ingebrit; Saether, Bjørn-Steinar

    2015-12-16

    A metabolomics approach was used to analyze effects of salmon farming on wild saithe (Pollachius virens) populations. Saithe fish were captured at two salmon farms and at two control locations around the island of Hitra, Norway. Changes in diet seem to drive changes in metabolic status of fishes. The liver and muscle tissues, from the fishes captured around the farm, showed higher levels of lactate and certain amino acids (glutamine, glutamate, and alanine) and lower levels of glucose and choline than the fishes captured in the control locations, far from the farm locations. The higher levels of lactate and amino acids could be related to the facility of obtaining food around the farm and the deficit in choline to the deficit of this nutrient in the salmon feed. At each location the fish were captured with either benthic gill nets and automatic jigging machines, and this feature showed also variations in different metabolites. PMID:26600204

  19. A Metabolomic Approach To Detect Effects of Salmon Farming on Wild Saithe (Pollachius virens) Populations.

    PubMed

    Maruhenda Egea, Frutos C; Toledo-Guedes, Kilian; Sanchez-Jerez, Pablo; Ibanco-Cañete, Ricardo; Uglem, Ingebrit; Saether, Bjørn-Steinar

    2015-12-16

    A metabolomics approach was used to analyze effects of salmon farming on wild saithe (Pollachius virens) populations. Saithe fish were captured at two salmon farms and at two control locations around the island of Hitra, Norway. Changes in diet seem to drive changes in metabolic status of fishes. The liver and muscle tissues, from the fishes captured around the farm, showed higher levels of lactate and certain amino acids (glutamine, glutamate, and alanine) and lower levels of glucose and choline than the fishes captured in the control locations, far from the farm locations. The higher levels of lactate and amino acids could be related to the facility of obtaining food around the farm and the deficit in choline to the deficit of this nutrient in the salmon feed. At each location the fish were captured with either benthic gill nets and automatic jigging machines, and this feature showed also variations in different metabolites.

  20. Spatial variation buffers temporal fluctuations in early juvenile survival for an endangered Pacific salmon.

    PubMed

    Thorson, James T; Scheuerell, Mark D; Buhle, Eric R; Copeland, Timothy

    2014-01-01

    Spatial, phenotypic and genetic diversity at relatively small scales can buffer species against large-scale processes such as climate change that tend to synchronize populations and increase temporal variability in overall abundance or production. This portfolio effect generally results in improved biological and economic outcomes for managed species. Previous evidence for the portfolio effect in salmonids has arisen from examinations of time series of adult abundance, but we lack evidence of spatial buffering of temporal variability in demographic rates such as survival of juveniles during their first year of life. We therefore use density-dependent population models with multiple random effects to represent synchronous (similar among populations) and asynchronous (different among populations) temporal variability as well as spatial variability in survival. These are fitted to 25 years of survey data for breeding adults and surviving juveniles from 15 demographically distinct populations of Chinook salmon (Oncorhynchus tshawytscha) within a single metapopulation in the Snake River in Idaho, USA. Model selection identifies the most support for the model that included both synchronous and asynchronous temporal variability, in addition to spatial variability. Asynchronous variability (log-SD = 0·55) is approximately equal in magnitude to synchronous temporal variability (log-SD = 0·67), but much lower than spatial variability (log-SD = 1·11). We also show that the pairwise correlation coefficient, a common measure of population synchrony, is approximated by the estimated ratio of shared and total variance, where both approaches yield a synchrony estimate of 0·59. We therefore find evidence for spatial buffering of temporal variability in early juvenile survival, although between-population variability that persists over time is also large. We conclude that spatial variation decreases interannual changes in overall juvenile production, which suggests that

  1. Stochastic modeling in biological populations with sexual reproduction through branching models: application to Coho salmon populations.

    PubMed

    Molina, Manuel; Mota, Manuel; Ramos, Alfonso

    2014-12-01

    The motivation behind this research is to develop appropriate mathematical models to describe the demographic dynamics of animal populations with sexual reproduction. We introduce a new class of two-sex branching models where several mating strategies between females and males and a variety of possibilities for the process of reproduction are taken into account. Unlike other classes of two-sex models which assume that mating and reproduction are influenced by the number of couples in the population, we now consider the most realistic case where both biological processes are affected by the numbers of females and males in the population, which may differ. Under a general parametric setting, we deal with inferential questions about the main parameters affecting the reproduction process. By considering the observation over time of the numbers of females and males up to when a certain pre-set generation is reached, we derive Bayes estimators for such parameters. With the purpose of determining highest posterior density credibility sets, we also propose a computational algorithm. As illustration, we include an application to Coho salmon populations.

  2. Potential responses to climate change in organisms with complex life histories: evolution and plasticity in Pacific salmon

    PubMed Central

    Crozier, L G; Hendry, A P; Lawson, P W; Quinn, T P; Mantua, N J; Battin, J; Shaw, R G; Huey, R B

    2008-01-01

    Salmon life histories are finely tuned to local environmental conditions, which are intimately linked to climate. We summarize the likely impacts of climate change on the physical environment of salmon in the Pacific Northwest and discuss the potential evolutionary consequences of these changes, with particular reference to Columbia River Basin spring/summer Chinook (Oncorhynchus tshawytscha) and sockeye (Oncorhynchus nerka) salmon. We discuss the possible evolutionary responses in migration and spawning date egg and juvenile growth and development rates, thermal tolerance, and disease resistance. We know little about ocean migration pathways, so cannot confidently suggest the potential changes in this life stage. Climate change might produce conflicting selection pressures in different life stages, which will interact with plastic (i.e. nongenetic) changes in various ways. To clarify these interactions, we present a conceptual model of how changing environmental conditions shift phenotypic optima and, through plastic responses, phenotype distributions, affecting the force of selection. Our predictions are tentative because we lack data on the strength of selection, heritability, and ecological and genetic linkages among many of the traits discussed here. Despite the challenges involved in experimental manipulation of species with complex life histories, such research is essential for full appreciation of the biological effects of climate change. PMID:25567630

  3. Using hierarchical models to estimate effects of ocean anomalies on north-west Pacific Chinook salmon Oncorhynchus tshawytscha recruitment.

    PubMed

    Sharma, R; Liermann, M

    2010-11-01

    The high variability in survival over the past three decades of north-west Pacific Chinook salmon Oncorhynchus tshawytscha is summarized for 24 stocks and analysed using hierarchical Bayesian models. Results from a simple model indicate that recruitment anomalies appear to be correlated in time and space. A simple model with a covariate based on basin-scale effects (Pacific Decadal Oscillation and El Niño Southern Oscillation) and local-scale effects (sea surface temperature, SST anomaly) was introduced to explain this variability. The model still exhibited residual patterns that were removed when a random-walk component was added to the model. The analysis indicates that recruitment is negatively related to SST anomaly for all stocks and the effect of basin-scale variables is negligible. The effect of climate over the next century is expected to result in estimated recruitment declining by an average of 13% for O. tshawytscha stocks coastwide.

  4. Modeling population responses of Chinook and coho salmon to suspended sediment using a life history approach.

    PubMed

    Araujo, H Andres; Cooper, Andrew B; MacIsaac, Erland A; Knowler, Duncan; Velez-Espino, Antonio

    2015-08-01

    This study develops a quantitative framework for estimating the effects of extreme suspended-sediment events (SSC>25 mg L(-1)) on virtual populations of Chinook (Oncorhynchus tshawytscha) and coho (O. kisutch) salmon in a coastal watershed of British Columbia, Canada. We used a life history model coupled with a dose-response model to evaluate the populations' responses to a set of simulated suspended sediments scenarios. Our results indicate that a linear increase in SSC produces non-linear declining trajectories in both Chinook and coho populations, but this decline was more evident for Chinook salmon despite their shorter fresh-water residence. The model presented here can provide insights into SSC impacts on population responses of salmonids and potentially assist resource managers when planning conservation or remediation strategies. PMID:25963631

  5. Fine-scale population structure in Atlantic salmon from Maine's Penobscot River drainage

    USGS Publications Warehouse

    Spidle, A.P.; Bane, Schill W.; Lubinski, B.A.; King, T.L.

    2001-01-01

    We report a survey of micro satellite DNA variation in Atlantic salmon from the unimpounded lower reaches of Maine's Penobscot River. Our analysis indicates that Atlantic salmon in the Penobscot River are distinct from other populations that have little or no history of human-mediated repopulation, including two of its tributaries, Cove Brook and Kenduskeag Stream, another Maine river, the Ducktrap, and Canada's Miramichi and Gander rivers. Significant heterogeneity was detected in allele frequency among all three subpopulations sampled in the Penobscot drainage. The high resolution of the 12-locus suite was quantified using maximum likelihood assignment tests, which correctly identified the source of 90.4-96.1% of individuals from within the Penobscot drainage. Current populations are clearly isolated from each other, however we are unable to determine from the present data whether the populations in Cove Brook and Kenduskeag Stream are recently diverged from populations stocked into the Penobscot River over the last century, or are aboriginal in origin. The degree of population structure identified in the Penobscot drainage is noteworthy in light of its lengthy history of systematic restocking, the geographic proximity of the subpopulations, and the extent of the differentiation. Similar population structure on this extremely limited geographic scale could exist among Atlantic salmon runs elsewhere in Maine and throughout the species' range and should be taken into account for future management decisions.

  6. Nutrient fluxes and the recent collapse of coastal California salmon populations

    USGS Publications Warehouse

    Moore, Jonathan W.; Hayes, Sean A.; Duffy, Walter; Gallagher, Sean; Michel, Cyril J.; Wright, David

    2011-01-01

    Migratory salmon move nutrients both in and out of fresh waters during the different parts of their life cycle. We used a mass-balance approach to quantify recent changes in phosphorus (P) fluxes in six coastal California, USA, watersheds that have recently experienced dramatic decreases in salmon populations. As adults, semelparous Chinook (Oncorhynchus tshawytscha) and coho (Oncorhynchus kisutch) salmon imported 8.3 and 10.4 times more P from the ocean, respectively, than they exported as smolts, while iteroparous steelhead (i.e., sea-run rainbow trout, Oncorhynchus mykiss) imported only 1.6 times more than they exported as kelts and smolts. Semelparous species whose life histories led them to import more nutrients were also the species whose populations decreased the most dramatically in California in recent years. In addition, the relationship between import and export was nonlinear, with export being proportionally more important at lower levels of import. This pattern was driven by two density-dependent processes — smolts were larger and disproportionately more abundant at lower spawner abundances. In fact, in four of our six streams we found evidence that salmon can drive net export of P at low abundance, evidence for the reversal of the "conveyor belt" of nutrients.

  7. Trans-Pacific RAD-Seq population genomics confirms introgressive hybridization in Eastern Pacific Pocillopora corals.

    PubMed

    Combosch, David J; Vollmer, Steven V

    2015-07-01

    Discrepancies between morphology-based taxonomy and phylogenetic systematics are common in Scleractinian corals. In Pocillopora corals, nine recently identified genetic lineages disagree fundamentally with the 17 recognized Pocillopora species, including 5 major Indo-Pacific reef-builders. Pocillopora corals hybridize in the Tropical Eastern Pacific, so it is possible that some of the disagreement between the genetics and taxonomy may be due to introgressive hybridization. Here we used 6769 genome-wide SNPs from Restriction-site Associated DNA Sequencing (RAD-Seq) to conduct phylogenomic comparisons among three common, Indo-Pacific Pocillopora species - P. damicornis, P. eydouxi and P. elegans - within and between populations in the Tropical Eastern Pacific (TEP) and the Central Pacific. Genome-wide RAD-Seq comparisons of Central and TEP Pocillopora confirm that the morphospecies P. damicornis, P. eydouxi and P. elegans are not monophyletic, but instead fall into three distinct genetic groups. However, hybrid samples shared fixed alleles with their respective parental species and, even without strict monophyly, P. damicornis share a common set of 33 species-specific alleles across the Pacific. RAD-Seq data confirm the pattern of one-way introgressive hybridization among TEP Pocillopora, suggesting that introgression may play a role in generating shared, polyphyletic lineages among currently recognized Pocillopora species. Levels of population differentiation within genetic lineages indicate significantly higher levels of population differentiation in the Tropical Eastern Pacific than in the Central West Pacific.

  8. Adaptive strategies and life history characteristics in a warming climate: salmon in the Arctic?

    USGS Publications Warehouse

    Nielsen, Jennifer L.; Ruggerone, Gregory T.; Zimmerman, Christian E.

    2013-01-01

    In the warming Arctic, aquatic habitats are in flux and salmon are exploring their options. Adult Pacific salmon, including sockeye (Oncorhynchus nerka), coho (O. kisutch), Chinook (O. tshawytscha), pink (O. gorbuscha) and chum (O. keta) have been captured throughout the Arctic. Pink and chum salmon are the most common species found in the Arctic today. These species are less dependent on freshwater habitats as juveniles and grow quickly in marine habitats. Putative spawning populations are rare in the North American Arctic and limited to pink salmon in drainages north of Point Hope, Alaska, chum salmon spawning rivers draining to the northwestern Beaufort Sea, and small populations of chum and pink salmon in Canada’s Mackenzie River. Pacific salmon have colonized several large river basins draining to the Kara, Laptev and East Siberian seas in the Russian Arctic. These populations probably developed from hatchery supplementation efforts in the 1960’s. Hundreds of populations of Arctic Atlantic salmon (Salmo salar) are found in Russia, Norway and Finland. Atlantic salmon have extended their range eastward as far as the Kara Sea in central Russian. A small native population of Atlantic salmon is found in Canada’s Ungava Bay. The northern tip of Quebec seems to be an Atlantic salmon migration barrier for other North American stocks. Compatibility between life history requirements and ecological conditions are prerequisite for salmon colonizing Arctic habitats. Broad-scale predictive models of climate change in the Arctic give little information about feedback processes contributing to local conditions, especially in freshwater systems. This paper reviews the recent history of salmon in the Arctic and explores various patterns of climate change that may influence range expansions and future sustainability of salmon in Arctic habitats. A summary of the research needs that will allow informed expectation of further Arctic colonization by salmon is given.

  9. Evidence of recent signatures of selection during domestication in an Atlantic salmon population.

    PubMed

    Gutierrez, A P; Yáñez, J M; Davidson, W S

    2016-04-01

    Selective breeding practices in Atlantic salmon aquaculture have been carried out intensively since the 1970s. Along with the phenotypic improvement of fish, we expect to observe genomic regions showing evidence of selection for traits related to growth and age at sexual maturation, as well as traits involved in the domestication process. This is mainly linked to the increase in the frequency of favourable alleles at loci that affect the traits of interest in the breeding population. In this study we searched for signatures of selection in the Cermaq Atlantic salmon broodstock, a Mowi strain, which was derived from wild Norwegian populations, and is now farmed in British Columbia, Canada. A 6.5K SNP array was used to genotype 202 fish from the Cermaq population, and the genotypes were compared with four wild populations from Norway. We used three methods based on FST values to detect signatures of selection. Forty four markers showing divergence in allele frequency were identified as outliers by the three detection methods, suggesting the presence of signatures of selection in the Cermaq population relative to their wild counterparts. Markers identified as outliers are associated with molecular functions that could be related to the selection for economically important traits (e.g., growth) as well as the domestication process (e.g., response to pathogens and environmental stressors). Of particular interest were three outlier markers that had been previously associated with grilsing (i.e., early sexual maturation) an undesirable trait, which has been heavily selected against in Atlantic salmon aquaculture. This study provides clear evidence of the presence of signatures of selection and domestication in a farmed Atlantic salmon population.

  10. History of salmon in the Great Lakes, 1850-1970

    USGS Publications Warehouse

    Parsons, John W.

    1973-01-01

    This history of the salmon in the Great Lakes describes the decline and extinction of the Atlantic salmon (Salmo salar) in Lake Ontario in the 1800's; the failure to establish, by salmon culture, permanent or sizable populations of Atlantic or Pacific salmon in any of the Great Lakes in 1867-1965; and the success of the plantings of coho (Oncorhynchus kisutch) and chinook salmon (O. tshawytsha) in the Great Lakes, in 1966-70 -- particularly in Lake Michigan. Despite plantings of 5 million fry and fingerlings from Lake Ontario stocks in 1866-84, the native Atlantic salmon in Lake Ontario became extinct in the late 1800's primarily because tributaries in which they spawned were blocked by mill dams. Plantings of 13 million chinook salmon and landlocked and anadromous forms of Atlantic salmon in Lake Ontario and the other Great Lakes in 1873-1947 failed completely. The first species to develop a self-sustaining population was the pink salmon (O. gorbuscha), which was planted in Lake Superior in 1956; however, it has not become abundant. A salmon fishery finally was established when 15 million coho salmon and 6 million chinook salmon were planted as smolt in the Great Lakes in 1966-70. In 1970, for example, 576,000 coho salmon (12% of those planted in 1969) were caught by anglers in Lake Michigan. Most weighed 5 to 10 pounds (2.3-4.5 kg). Sport fishing for salmon was fair in Lakes Superior and Huron, and poor in Lakes Erie and Ontario. By 1970, natural reproduction of coho, chinook, pink, and kokanee (O. nerka) salmon had occurred in some tributaries of one or more of the upper three Great Lakes. It is expected, however, that the sport fishery will continue to be supported almost entirely by planted fish.

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

    SciTech Connect

    Berejikian, Barry

    2004-01-01

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

  12. Alternative reproductive tactics increase effective population size and decrease inbreeding in wild Atlantic salmon

    PubMed Central

    Perrier, Charles; Normandeau, Éric; Dionne, Mélanie; Richard, Antoine; Bernatchez, Louis

    2014-01-01

    While nonanadromous males (stream-resident and/or mature male parr) contribute to reproduction in anadromous salmonids, little is known about their impacts on key population genetic parameters. Here, we evaluated the contribution of Atlantic salmon mature male parr to the effective number of breeders (Nb) using both demographic (variance in reproductive success) and genetic (linkage disequilibrium) methods, the number of alleles, and the relatedness among breeders. We used a recently published pedigree reconstruction of a wild anadromous Atlantic salmon population in which 2548 fry born in 2010 were assigned parentage to 144 anadromous female and 101 anadromous females that returned to the river to spawn in 2009 and to 462 mature male parr. Demographic and genetic methods revealed that mature male parr increased population Nb by 1.79 and 1.85 times, respectively. Moreover, mature male parr boosted the number of alleles found among progenies. Finally, mature male parr were in average less related to anadromous females than were anadromous males, likely because of asynchronous sexual maturation between mature male parr and anadromous fish of a given cohort. By increasing Nb and allelic richness, and by decreasing inbreeding, the reproductive contribution of mature male parr has important evolutionary and conservation implications for declining Atlantic salmon populations. PMID:25553070

  13. Alternative reproductive tactics increase effective population size and decrease inbreeding in wild Atlantic salmon.

    PubMed

    Perrier, Charles; Normandeau, Éric; Dionne, Mélanie; Richard, Antoine; Bernatchez, Louis

    2014-11-01

    While nonanadromous males (stream-resident and/or mature male parr) contribute to reproduction in anadromous salmonids, little is known about their impacts on key population genetic parameters. Here, we evaluated the contribution of Atlantic salmon mature male parr to the effective number of breeders (Nb) using both demographic (variance in reproductive success) and genetic (linkage disequilibrium) methods, the number of alleles, and the relatedness among breeders. We used a recently published pedigree reconstruction of a wild anadromous Atlantic salmon population in which 2548 fry born in 2010 were assigned parentage to 144 anadromous female and 101 anadromous females that returned to the river to spawn in 2009 and to 462 mature male parr. Demographic and genetic methods revealed that mature male parr increased population Nb by 1.79 and 1.85 times, respectively. Moreover, mature male parr boosted the number of alleles found among progenies. Finally, mature male parr were in average less related to anadromous females than were anadromous males, likely because of asynchronous sexual maturation between mature male parr and anadromous fish of a given cohort. By increasing Nb and allelic richness, and by decreasing inbreeding, the reproductive contribution of mature male parr has important evolutionary and conservation implications for declining Atlantic salmon populations.

  14. Population genomic analyses of early-phase Atlantic Salmon (Salmo salar) domestication/captive breeding

    PubMed Central

    Mäkinen, Hannu; Vasemägi, Anti; McGinnity, Philip; Cross, Tom F; Primmer, Craig R

    2015-01-01

    Domestication can have adverse genetic consequences, which may reduce the fitness of individuals once released back into the wild. Many wild Atlantic salmon (Salmo salarL.) populations are threatened by anthropogenic influences, and they are supplemented with captively bred fish. The Atlantic salmon is also widely used in selective breeding programs to increase the mean trait values for desired phenotypic traits. We analyzed a genomewide set of SNPs in three domesticated Atlantic salmon strains and their wild conspecifics to identify loci underlying domestication. The genetic differentiation between domesticated strains and wild populations was low (FST < 0.03), and domesticated strains harbored similar levels of genetic diversity compared to their wild conspecifics. Only a few loci showed footprints of selection, and these loci were located in different linkage groups among the different wild population/hatchery strain comparisons. Simulated scenarios indicated that differentiation in quantitative trait loci exceeded that in neutral markers during the early phases of divergence only when the difference in the phenotypic optimum between populations was large. This study indicates that detecting selection using standard approaches in the early phases of domestication might be challenging unless selection is strong and the traits under selection show simple inheritance patterns. PMID:25667605

  15. Modernisation, migration and nutritional health of Pacific Island populations.

    PubMed

    Ulijaszek, Stanley

    2005-01-01

    The emergence of obesity and fatness across the second part of the 20th century has been documented for a number of Pacific Island populations. While dietary change and reduced physical activity levels associated with economic modernisation have been identified as the key factors fuelling the emergence of obesity, it is argued here that increasing numbers of Pacific Island migrants in the United States, New Zealand, France and Australia have provided the basis for the acceleration of the modernisation process by way of remittances, and the transmission of ideas of economic opportunity and change. Potential for migration for the Pacific Island nations is estimated from available data on population growth, total fertility rates and total mortality rates. Pacific Islander migrants form approximately one quarter of the total global Pacific Islander population, the majority of whom are from Tonga, Fiji, French Polynesia, and the Federated States of Micronesia. Per capita energy and fats and meat intake for the period 1961 to 2000 is described for five Pacific Island nations, showing that, in general, energy intakes have increased, as have the energy densities of the diets consumed. Thus the increase in mean body mass index observed in Pacific Islanders in the second half of the twentieth century can in general be attributed to dietary change associated with greater food and energy intake, and with increased consumption of fatty foods and meat, most of which are imports.

  16. Evaluate Factors Limiting Columbia River Gorge Chum Salmon Populations : FY2001 Annual Report.

    SciTech Connect

    Hoffman, Thomas A.

    2001-12-01

    Juvenile and adult chum salmon were monitored in fiscal year 2001 to continue evaluating factors limiting production. Total adult salmon caught (in weirs or by carcass surveys) in Hardy Creek and Hamilton Springs in 2000 was 25 and 130 fish, respectively. Fifty-two fish captured in the main stem Columbia River, Hamilton Springs, Hardy Creek, or Bonneville Dam were implanted with radio tags and tracked with an array of fixed aerials and underwater antennae. Males tended to move greater distances than females. Population estimates in Hardy Creek and Hamilton Springs were 37{+-}2 and 157{+-}5, respectively. Chum smolt emigration began in Hamilton Springs 25 February 2001 and 2 March 2001 in Hardy Creek. Total catches in Hardy Creek and Hamilton Springs were 2,955 and 14,967, respectively. Population abundance estimates were 11,586{+-}1,836 in Hardy Creek and 84,520{+-}9,283 in Hamilton Springs.

  17. Growth and survival of pacific coho salmon smolts exposed as juveniles to pesticides within urban streams in western Washington, USA.

    PubMed

    King, Kerensa A; Grue, Christian E; Grassley, James M; Fisk, Robert J; Conquest, Loveday L

    2014-07-01

    Pesticides are frequently detected in urban streams, with concentrations often exceeding those reported in surface waters within agricultural areas. The authors studied growth, survival, and return rates of coho salmon (Oncorhynchus kisutch) smolts exposed to a pesticide mixture ("cocktail") representative of the pesticides most frequently reported within urban streams in western Washington State, USA, in fall through early spring. Exposure concentrations were selected to represent a reasonable worst-case scenario based on field monitoring data. Smolts were continuously exposed to pulses of the cocktail either from fertilization through swim-up (2007-2008) or from fertilization through smoltification (2007-2008 and 2008-2009), coded wire tagged, and released in 2008 and 2009. Pre-release endpoints (growth, survival, sex ratio, brain acetylcholinesterase activity, and gonado- and hepatosomatic indices) were not affected. However, the number of returning adults exposed to the cocktail to swim-up (0.90%, n = 42) was more than double that of unexposed controls (0.38%, n = 26) in 2008, whereas in 2009, fish exposed through smoltification returned in lower numbers (0.15%, n = 18) than controls (0.37%, n = 30). Variability in return rates among treatments between years was comparable to that observed in previous whole life cycle studies with Pacific salmon and other contaminants. Results suggest that exposure to pesticides in urban streams does not directly impair early life stages of coho salmon, and that additional studies incorporating releases of larger numbers of smolts across several years are necessary to adequately quantify effects on return rates.

  18. Species- and sex-specific responses and recovery of wild, mature pacific salmon to an exhaustive exercise and air exposure stressor.

    PubMed

    Donaldson, Michael R; Hinch, Scott G; Jeffries, Ken M; Patterson, David A; Cooke, Steven J; Farrell, Anthony P; Miller, Kristina M

    2014-03-01

    Despite the common mechanisms that underlie vertebrate responses to exhaustive exercise stress, the magnitude and the timecourse of recovery can be context-specific. Here, we examine how wild, adult male and female pink (Oncorhynchus gorbuscha) and sockeye (Oncorhynchus nerka) salmon respond to and recover from an exhaustive exercise and air exposure stressor, designed to simulate fisheries capture and handling. We follow gill tissue gene expression for genes active in cellular stress, cell maintenance, and apoptosis as well as plasma osmoregulatory, stress, and reproductive indices. The stressor initiated a major stress response as indicated by increased normalised expression of two stress-responsive genes, Transcription Factor JUNB and cytochrome C (pink salmon only). The stressor resulted in increased plasma ion cortisol, lactate, and depressed estradiol (sockeye salmon only). Gene expression and plasma variables showed a general recovery by 24h post-stressor. Species- and sex-specific patterns were observed in stress response and recovery, with pink salmon mounting a higher magnitude stress response for plasma variables and sockeye salmon exhibiting a higher and more variable gene expression profile. These results highlight species- and sex-specific responses of migrating Pacific salmon to simulated fisheries encounters, which contribute new knowledge towards understanding the consequences of fisheries capture-and-release. PMID:24607368

  19. 77 FR 75570 - Fisheries of the Exclusive Economic Zone Off Alaska; Pacific Salmon

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-21

    ... Federal Register on April 2, 2012 (77 FR 19605) with comments invited through June 1, 2012. NMFS published a proposed rule to implement Amendment 12 on April 11, 2012 (77 FR 21716) with comments invited... State of Alaska (Alaska) management of commercial and sport fishing for salmon in the East Area....

  20. A SALMON-CENTRIC VIEW OF THE 21ST CENTURY IN THE PACIFIC NORTHWEST

    EPA Science Inventory

    Throughout the far western contiguous United States (California, Oregon, Washington, and Idaho), many wild salmon stocks have declined and some have disappeared. The decline has taken place over the past 150 years and, although there have been decades when the numbers increased,...

  1. Population Education in Asia and the Pacific Newsletter, Number 23.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and the Pacific.

    This UNESCO newsletter contains six sections concerned with various aspects of population education. Section 1 deals with workshops for monitoring and evaluating population education programs. Section 2 evaluates the programs of six Asia-Pacific countries (China, Democratic People's Republic of Korea, India, Pakistan, Philippines, and Thailand).…

  2. 50 CFR Table 1 to Subpart H of... - Pacific Salmon EFH Identified by USGS Hydrologic Unit Code (HUC)

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Name Salmon Species Impassible Man-made Barrier (if present) 17110001 WA Fraser (Whatcom) Coho salmon n/a 17110002 WA Strait of Georgia Chinook, coho, and pink salmon n/a 17110003 WA San Juan Islands... Lower Columbia-Sandy River Chinook and coho salmon Impassable Man-made Barrier 17080002 WA Lewis...

  3. 50 CFR Table 1 to Subpart H of... - Pacific Salmon EFH Identified by USGS Hydrologic Unit Code (HUC)

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Name Salmon Species Impassible Man-made Barrier (if present) 17110001 WA Fraser (Whatcom) Coho salmon n/a 17110002 WA Strait of Georgia Chinook, coho, and pink salmon n/a 17110003 WA San Juan Islands... Lower Columbia-Sandy River Chinook and coho salmon Impassable Man-made Barrier 17080002 WA Lewis...

  4. 50 CFR Table 1 to Subpart H of... - Pacific Salmon EFH Identified by USGS Hydrologic Unit Code (HUC)

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Name Salmon Species Impassible Man-made Barrier (if present) 17110001 WA Fraser (Whatcom) Coho salmon n/a 17110002 WA Strait of Georgia Chinook, coho, and pink salmon n/a 17110003 WA San Juan Islands... Lower Columbia-Sandy River Chinook and coho salmon Impassable Man-made Barrier 17080002 WA Lewis...

  5. 50 CFR Table 1 to Subpart H of... - Pacific Salmon EFH Identified by USGS Hydrologic Unit Code (HUC)

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Name Salmon Species Impassible Man-made Barrier (if present) 17110001 WA Fraser (Whatcom) Coho salmon n/a 17110002 WA Strait of Georgia Chinook, coho, and pink salmon n/a 17110003 WA San Juan Islands... Lower Columbia-Sandy River Chinook and coho salmon Impassable Man-made Barrier 17080002 WA Lewis...

  6. Fishing for Effective Conservation: Context and Biotic Variation are Keys to Understanding the Survival of Pacific Salmon after Catch-and-Release.

    PubMed

    Raby, Graham D; Donaldson, Michael R; Hinch, Scott G; Clark, Timothy D; Eliason, Erika J; Jeffries, Kenneth M; Cook, Katrina V; Teffer, Amy; Bass, Arthur L; Miller, Kristina M; Patterson, David A; Farrell, Anthony P; Cooke, Steven J

    2015-10-01

    Acute stressors are commonly experienced by wild animals but their effects on fitness rarely are studied in the natural environment. Billions of fish are captured and released annually around the globe across all fishing sectors (e.g., recreational, commercial, subsistence). Whatever the motivation, release often occurs under the assumption of post-release survival. Yet, capture by fisheries (hereafter "fisheries-capture") is likely the most severe acute stressor experienced in the animal's lifetime, which makes the problem of physiological recovery and survival of relevance to biology and conservation. Indeed, fisheries managers require accurate estimates of mortality to better account for total mortality from fishing, while fishers desire guidance on strategies for reducing mortality and maintaining the welfare of released fish, to maximize current and future opportunities for fishing. In partnership with stakeholders, our team has extensively studied the effects of catch-and-release on Pacific salmon in both marine and freshwater environments, using biotelemetry and physiological assessments in a combined laboratory-based and field-based approach. The emergent theme is that post-release rates of mortality are consistently context-specific and can be affected by a suite of interacting biotic and abiotic factors. The fishing gear used, location of a fishery, water temperature, and handling techniques employed by fishers each can dramatically affect survival of the salmon they release. Variation among individuals, co-migrating populations, and between sexes all seem to play a role in the response of fish to capture and in their subsequent survival, potentially driven by pre-capture pathogen-load, maturation states, and inter-individual variation in responsiveness to stress. Although some of these findings are fascinating from a biological perspective, they all create unresolved challenges for managers. We summarize our findings by highlighting the patterns that

  7. It's a bear market: evolutionary and ecological effects of predation on two wild sockeye salmon populations.

    PubMed

    Lin, J E; Hard, J J; Naish, K A; Peterson, D; Hilborn, R; Hauser, L

    2016-05-01

    Predation can affect both phenotypic variation and population productivity in the wild, but quantifying evolutionary and demographic effects of predation in natural environments is challenging. The aim of this study was to estimate selection differentials and coefficients associated with brown bear (Ursus arctos) predation in wild sockeye salmon (Oncorhynchus nerka) populations spawning in pristine habitat that is often subject to intense predation pressure. Using reconstructed genetic pedigrees, individual reproductive success (RS) was estimated in two sockeye salmon populations for two consecutive brood years with very different predation intensities across brood years. Phenotypic data on individual adult body length, body depth, stream entry timing and reproductive lifespan were used to calculate selection coefficients based on RS, and genetic variance components were estimated using animal models. Bears consistently killed larger and more recently arrived adults, although selection differentials were small. In both populations, mean RS was higher in the brood year experiencing lower predation intensity. Selection coefficients were similar across brood years with different levels of predation, often indicating stabilizing selection on reproductive lifespan as well as directional selection for longer reproductive lifespan. Despite these selection pressures, genetic covariation of morphology, phenology and lifespan appears to have maintained variation in spawner body size and stream entry timing in both populations. Our results therefore suggest considerable demographic but limited evolutionary effects of bear predation in the two study populations.

  8. It's a bear market: evolutionary and ecological effects of predation on two wild sockeye salmon populations.

    PubMed

    Lin, J E; Hard, J J; Naish, K A; Peterson, D; Hilborn, R; Hauser, L

    2016-05-01

    Predation can affect both phenotypic variation and population productivity in the wild, but quantifying evolutionary and demographic effects of predation in natural environments is challenging. The aim of this study was to estimate selection differentials and coefficients associated with brown bear (Ursus arctos) predation in wild sockeye salmon (Oncorhynchus nerka) populations spawning in pristine habitat that is often subject to intense predation pressure. Using reconstructed genetic pedigrees, individual reproductive success (RS) was estimated in two sockeye salmon populations for two consecutive brood years with very different predation intensities across brood years. Phenotypic data on individual adult body length, body depth, stream entry timing and reproductive lifespan were used to calculate selection coefficients based on RS, and genetic variance components were estimated using animal models. Bears consistently killed larger and more recently arrived adults, although selection differentials were small. In both populations, mean RS was higher in the brood year experiencing lower predation intensity. Selection coefficients were similar across brood years with different levels of predation, often indicating stabilizing selection on reproductive lifespan as well as directional selection for longer reproductive lifespan. Despite these selection pressures, genetic covariation of morphology, phenology and lifespan appears to have maintained variation in spawner body size and stream entry timing in both populations. Our results therefore suggest considerable demographic but limited evolutionary effects of bear predation in the two study populations. PMID:26860201

  9. Low cardiac and aerobic scope in a coastal population of sockeye salmon Oncorhynchus nerka with a short upriver migration.

    PubMed

    Eliason, E J; Wilson, S M; Farrell, A P; Cooke, S J; Hinch, S G

    2013-06-01

    This study showed that a coastal population (Harrison) of Fraser River sockeye salmon Oncorhynchus nerka had a lower aerobic and cardiac scope compared with interior populations with more challenging upriver spawning migrations, providing additional support to the idea that Fraser River O. nerka populations have adapted physiologically to their local migratory environment. PMID:23731155

  10. Incidence of Clostridium botulinum Type E in Salmon and Other Marine Fish in the Pacific Northwest

    PubMed Central

    Craig, James M.; Hayes, Sidney; Pilcher, K. S.

    1968-01-01

    Salmon, sole, cod, oysters, clams, and crabs from ocean waters along the coast of Oregon and Washington were examined for the presence of Clostridium botulinum type E. The organism was detected by identification of the type E toxin in enrichment cultures of the viscera of individual fish. Of 369 salmon specimens, 48 yielded cultures containing toxin lethal to mice, and almost half of the toxic cultures were shown to contain botulinal toxin, chiefly type E. Eighteen of 113 sole and cod specimens, 4 of 22 Dungeness crab specimens, 5 of 16 oyster specimens, and 27 of 115 clam specimens gave rise to cultures containing botulinal toxin which was usually type E, although types A and B were occasionally encountered. PMID:4869616

  11. [Mitochondrial DNA variation in populations of the chum salmon Oncorhynchus keta (Walbaum) from rivers of the Prymorye and Sakhalin].

    PubMed

    Brykov, V A; Kirillova, O N; Kukhlevskiĭ, A D; Poliakova, N E; Skurikhina, L A

    2000-10-01

    Mitochondrial DNA (mtDNA) variation was studied using restriction fragment length polymorphism (RFLP) in chum salmon populations from three rivers in southern Primorye and one river in Sakhalin Island. Significant differences were detected between the samples from Primorye and Sakhalin Island. No differences were found between the samples from the rivers of Primorye, which can be explained by a high rate of gene flow due to transplantation of spawn from one river to another. The effect of fish breeding on the chum salmon populations correlated with the indices of haplotype and nucleotide diversity (h and pi, respectively). The lowest diversity was found in the completely artificial population from the Ryazanovka River; the highest, in natural populations from the Narva and Naiba rivers. Frequencies of haplotypes in consecutive generations were significantly different, which confirms the effects of genetic drift on the small-size chum salmon populations of Primorye.

  12. Can reduced predation offset negative effects of sea louse parasites on chum salmon?

    PubMed

    Peacock, Stephanie J; Connors, Brendan M; Krkosek, Martin; Irvine, James R; Lewis, Mark A

    2014-02-01

    The impact of parasites on hosts is invariably negative when considered in isolation, but may be complex and unexpected in nature. For example, if parasites make hosts less desirable to predators then gains from reduced predation may offset direct costs of being parasitized. We explore these ideas in the context of sea louse infestations on salmon. In Pacific Canada, sea lice can spread from farmed salmon to migrating juvenile wild salmon. Low numbers of sea lice can cause mortality of juvenile pink and chum salmon. For pink salmon, this has resulted in reduced productivity of river populations exposed to salmon farming. However, for chum salmon, we did not find an effect of sea louse infestations on productivity, despite high statistical power. Motivated by this unexpected result, we used a mathematical model to show how a parasite-induced shift in predation pressure from chum salmon to pink salmon could offset negative direct impacts of sea lice on chum salmon. This shift in predation is proposed to occur because predators show an innate preference for pink salmon prey. This preference may be more easily expressed when sea lice compromise juvenile salmon hosts, making them easier to catch. Our results indicate how the ecological context of host-parasite interactions may dampen, or even reverse, the expected impact of parasites on host populations.

  13. Can reduced predation offset negative effects of sea louse parasites on chum salmon?

    PubMed Central

    Peacock, Stephanie J.; Connors, Brendan M.; Krkošek, Martin; Irvine, James R.; Lewis, Mark A.

    2014-01-01

    The impact of parasites on hosts is invariably negative when considered in isolation, but may be complex and unexpected in nature. For example, if parasites make hosts less desirable to predators then gains from reduced predation may offset direct costs of being parasitized. We explore these ideas in the context of sea louse infestations on salmon. In Pacific Canada, sea lice can spread from farmed salmon to migrating juvenile wild salmon. Low numbers of sea lice can cause mortality of juvenile pink and chum salmon. For pink salmon, this has resulted in reduced productivity of river populations exposed to salmon farming. However, for chum salmon, we did not find an effect of sea louse infestations on productivity, despite high statistical power. Motivated by this unexpected result, we used a mathematical model to show how a parasite-induced shift in predation pressure from chum salmon to pink salmon could offset negative direct impacts of sea lice on chum salmon. This shift in predation is proposed to occur because predators show an innate preference for pink salmon prey. This preference may be more easily expressed when sea lice compromise juvenile salmon hosts, making them easier to catch. Our results indicate how the ecological context of host–parasite interactions may dampen, or even reverse, the expected impact of parasites on host populations. PMID:24352951

  14. Can reduced predation offset negative effects of sea louse parasites on chum salmon?

    PubMed

    Peacock, Stephanie J; Connors, Brendan M; Krkosek, Martin; Irvine, James R; Lewis, Mark A

    2014-02-01

    The impact of parasites on hosts is invariably negative when considered in isolation, but may be complex and unexpected in nature. For example, if parasites make hosts less desirable to predators then gains from reduced predation may offset direct costs of being parasitized. We explore these ideas in the context of sea louse infestations on salmon. In Pacific Canada, sea lice can spread from farmed salmon to migrating juvenile wild salmon. Low numbers of sea lice can cause mortality of juvenile pink and chum salmon. For pink salmon, this has resulted in reduced productivity of river populations exposed to salmon farming. However, for chum salmon, we did not find an effect of sea louse infestations on productivity, despite high statistical power. Motivated by this unexpected result, we used a mathematical model to show how a parasite-induced shift in predation pressure from chum salmon to pink salmon could offset negative direct impacts of sea lice on chum salmon. This shift in predation is proposed to occur because predators show an innate preference for pink salmon prey. This preference may be more easily expressed when sea lice compromise juvenile salmon hosts, making them easier to catch. Our results indicate how the ecological context of host-parasite interactions may dampen, or even reverse, the expected impact of parasites on host populations. PMID:24352951

  15. Population characteristics and health care needs of Asian Pacific Americans.

    PubMed

    Lin-Fu, J S

    1988-01-01

    Asian Pacific Americans are one of the smallest but fastest growing minority groups in the United States. Between 1970 and 1980, this population increased 142 percent, from 1.5 million to 3.7 million. This dramatic growth is due largely to a change in U.S. immigration policies in the mid-1960s and the continuous influx of refugees from Southeast Asia since 1975. Despite such sharp increase, Asian Pacific Americans remain one of the most poorly understood minorities, and their health care needs have received relatively little attention. Health policy makers, planners, and service providers need to have a better understanding of the population characteristics of Asian Pacific Americans in order to address their needs properly. Asian Pacific Americans are largely recent immigrants and refugees. They are extremely heterogeneous and bipolar in socioeconomic status and health indices. Because of their small numbers until the last two decades, many health workers have had little exposure to this minority, their culture, and health problems. Health workers need to be sensitive to the ethnocultural barriers that confront recent arrivals; be aware of the genetic disorders, infectious diseases, and mental health problems common in this population; and realize that anatomical and physiological differences may require attention in certain surgical procedures and medical management. Neglecting the health care needs of Asian Pacific Americans is not simply a violation of the principle of equality for all, but also an imprudent act that increases the mortalities and morbidities and health care costs of the nation.

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

    SciTech Connect

    Rawding, Dan; Hillson, Todd D.

    2003-11-15

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

  17. Searching for a life history approach to salmon escapement management

    USGS Publications Warehouse

    Knudsen, E.E.; Symmes, E.W.; Margraf, F.J.

    2003-01-01

    A number of Pacific salmon populations have already been lost and many others throughout the range are in various states of decline. Recent research has documented that Pacific salmon carcasses serve as a key delivery vector of marine-derived nutrients into the freshwater portions of their ecosystems. This nutrient supply plays a critical biological feedback role in salmon sustainability by supporting juvenile salmon production. We first demonstrate how nutrient feedback potential to juvenile production may be unaccounted for in spawner-recruit models of populations under long-term exploitation. We then present a heuristic, life history-based, spreadsheet survival model that incorporates salmon carcass-driven nutrient feedback to the freshwater components of the salmon ecosystem. The productivity of a hypothetical coho salmon population was simulated using rates from the literature for survival from spawner to egg, egg to fry, fry to smolt, and smolt to adult. The effects of climate variation and nutrient feedback on survival were incorporated, as were density-dependent effects of the numbers of spawners and fry on freshwater survival of eggs and juveniles. The unexploited equilibrium population was subjected to 100 years of 20, 40, 60, and 80% harvest. Each harvest scenario greater than 20% brought the population to a reduced steady state, regardless of generous compensatory survival at low population sizes. Increasing harvest reduced the positive effects of nutrient contributions to population growth. Salmon researchers should further explore this modeling approach for establishing escapement goals. Given the importance of nutrient feedback, managers should strive for generous escapements that support nutrient rebuilding, as well as egg deposition, to ensure strong future salmon production.

  18. Self-sustaining populations, population sinks or aggregates of strays: chum (Oncorhynchus keta) and Chinook salmon (Oncorhynchus tshawytscha) in the Wood River system, Alaska.

    PubMed

    Lin, Jocelyn E; Hilborn, Ray; Quinn, Thomas P; Hauser, Lorenz

    2011-12-01

    Small populations can provide insights into ecological and evolutionary aspects of species distributions over space and time. In the Wood River system in Alaska, USA, small aggregates of Chinook (Oncorhynchus tshawytscha) and chum salmon (O. keta) spawn in an area dominated by sockeye salmon (O. nerka). Our objective was to determine whether these Chinook and chum salmon are reproductively isolated, self-sustaining populations, population sinks that produce returning adults but receive immigration, or strays from other systems that do not produce returning adults. DNA samples collected from adult chum salmon from 16 streams and Chinook salmon from four streams in the Wood River system over 3 years were compared to samples from large populations in the nearby Nushagak River system, a likely source of strays. For both species, microsatellite markers indicated no significant genetic differentiation between the two systems. Simulations of microsatellite data in a large source and a smaller sink population suggested that considerable immigration would be required to counteract the diverging effects of genetic drift and produce genetic distances as small as those observed, considering the small census sizes of the two species in the Wood River system. Thus, the Wood River system likely receives substantial immigration from neighbouring watersheds, such as the Nushagak River system, which supports highly productive runs. Although no data on population productivity in the Wood River system exist, our results suggest source-sink dynamics for the two species, a finding relevant to other systems where salmonid population sizes are limited by habitat factors.

  19. Determinants of hierarchical genetic structure in Atlantic salmon populations: environmental factors vs. anthropogenic influences.

    PubMed

    Perrier, Charles; Guyomard, René; Bagliniere, Jean-Luc; Evanno, Guillaume

    2011-10-01

    Disentangling the effects of natural environmental features and anthropogenic factors on the genetic structure of endangered populations is an important challenge for conservation biology. Here, we investigated the combined influences of major environmental features and stocking with non-native fish on the genetic structure and local adaptation of Atlantic salmon (Salmo salar) populations. We used 17 microsatellite loci to genotype 975 individuals originating from 34 French rivers. Bayesian analyses revealed a hierarchical genetic structure into five geographically distinct clusters. Coastal distance, geological substrate and river length were strong predictors of population structure. Gene flow was higher among rivers with similar geologies, suggesting local adaptation to geological substrate. The effect of river length was mainly owing to one highly differentiated population that has the farthest spawning grounds off the river mouth (up to 900km) and the largest fish, suggesting local adaptation to river length. We detected high levels of admixture in stocked populations but also in neighbouring ones, implying large-scale impacts of stocking through dispersal of non-native individuals. However, we found relatively few admixed individuals suggesting a lower fitness of stocked fish and/or some reproductive isolation between wild and stocked individuals. When excluding stocked populations, genetic structure increased as did its correlation with environmental factors. This study overall indicates that geological substrate and river length are major environmental factors influencing gene flow and potential local adaptation among Atlantic salmon populations but that stocking with non-native individuals may ultimately disrupt these natural patterns of gene flow among locally adapted populations.

  20. Modeling (137)Cs bioaccumulation in the salmon-resident killer whale food web of the Northeastern Pacific following the Fukushima Nuclear Accident.

    PubMed

    Alava, Juan José; Gobas, Frank A P C

    2016-02-15

    To track the long term bioaccumulation of (137)Cs in marine organisms off the Pacific Northwest coast of Canada, we developed a time dependent bioaccumulation model for (137)Cs in a marine mammalian food web that included fish-eating resident killer whales. The model outcomes show that (137)Cs can be expected to gradually bioaccumulate in the food web over time as demonstrated by the increase of the apparent trophic magnification factor of (137)Cs, ranging from 0.76 after 1 month of exposure to 2.0 following 30 years of exposure. (137)Cs bioaccumulation is driven by relatively rapid dietary uptake rates, moderate depuration rates in lower trophic level organisms and slow elimination rates in high trophic level organisms. Model estimates of the (137)Cs activity in species of the food web, based on current measurements and forecasts of (137)Cs activities in oceanic waters and sediments off the Canadian Pacific Northwest, indicate that the long term (137)Cs activities in fish species including Pacific herring, wild Pacific salmon, sablefish and halibut will remain well below the current (137)Cs-Canada Action Level for consumption (1000 Bq/kg) following a nuclear emergency. Killer whales and Pacific salmon are expected to exhibit the largest long term (137)Cs activities and may be good sentinels for monitoring (137)Cs in the region. Assessment of the long term consequences of (137)Cs releases from the Fukushima aftermath should consider the extent of ecological magnification in addition to ocean dilution. PMID:26657356

  1. Modeling (137)Cs bioaccumulation in the salmon-resident killer whale food web of the Northeastern Pacific following the Fukushima Nuclear Accident.

    PubMed

    Alava, Juan José; Gobas, Frank A P C

    2016-02-15

    To track the long term bioaccumulation of (137)Cs in marine organisms off the Pacific Northwest coast of Canada, we developed a time dependent bioaccumulation model for (137)Cs in a marine mammalian food web that included fish-eating resident killer whales. The model outcomes show that (137)Cs can be expected to gradually bioaccumulate in the food web over time as demonstrated by the increase of the apparent trophic magnification factor of (137)Cs, ranging from 0.76 after 1 month of exposure to 2.0 following 30 years of exposure. (137)Cs bioaccumulation is driven by relatively rapid dietary uptake rates, moderate depuration rates in lower trophic level organisms and slow elimination rates in high trophic level organisms. Model estimates of the (137)Cs activity in species of the food web, based on current measurements and forecasts of (137)Cs activities in oceanic waters and sediments off the Canadian Pacific Northwest, indicate that the long term (137)Cs activities in fish species including Pacific herring, wild Pacific salmon, sablefish and halibut will remain well below the current (137)Cs-Canada Action Level for consumption (1000 Bq/kg) following a nuclear emergency. Killer whales and Pacific salmon are expected to exhibit the largest long term (137)Cs activities and may be good sentinels for monitoring (137)Cs in the region. Assessment of the long term consequences of (137)Cs releases from the Fukushima aftermath should consider the extent of ecological magnification in addition to ocean dilution.

  2. 78 FR 5162 - Designation of a Nonessential Experimental Population of Central Valley Spring-Run Chinook Salmon...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-01-24

    ... January 16, 2013 we, NMFS, published a proposed rule (78 FR 3381) to designate a nonessential experimental... Experimental Population of Central Valley Spring-Run Chinook Salmon Below Friant Dam in the San Joaquin River..., published a proposed rule to designate a nonessential experimental population of Central Valley...

  3. Population growth of Gyrodactylus salaris (Monogenea) on Norwegian and Baltic Atlantic salmon (Salmo salar) stocks.

    PubMed

    Cable, J; Harris, P D; Bakke, T A

    2000-12-01

    Reproductive success of Gvrodactylus salaris from River Lierelva was compared experimentally on 3 stocks of salmon (12.5 degrees C +/- 0.2). Isolated fish from 2 susceptible Norwegian stocks (Rivers Lier and Alta) and 1 resistant Baltic stock of salmon (River Neva) were infected with a single gravid worm in order to record the temporal sequence of births and age at death of individual parasites. Establishment success (proportion of worms surviving to give birth) was generally low and mortality high, but significantly fewer worms survived on Neva (45% with mean survival of 3.5 days) compared to Alta and Lier fish (60 % mean survival 7.9 and 5.2 days, respectively). There was a dramatic difference in parasite fecundity between the host stocks: only 2 births occurred on Neva fish compared to third and fourth births on both Alta and Lier hosts. The timing of the first birth was more variable on Neva hosts and was significantly extended (mean 2.3 days) relative to that on Alta and Neva fish (1.8 days). However, timing of the second birth did not vary on any of the 3 salmon stocks. Age-specific mortality and fecundity data are consistent with exponential population growth of G. salaris on Alta and Lier fish but eventual extinction on Neva hosts. This is the first demonstration that gyrodactylids maintained on different host stocks exhibit variations in fecundity, development and mortality, which may in turn account for the variable virulence noted when G. salaris infects different salmonid hosts.

  4. Genotyping by sequencing resolves shallow population structure to inform conservation of Chinook salmon (Oncorhynchus tshawytscha)

    PubMed Central

    Larson, Wesley A; Seeb, Lisa W; Everett, Meredith V; Waples, Ryan K; Templin, William D; Seeb, James E

    2014-01-01

    Recent advances in population genomics have made it possible to detect previously unidentified structure, obtain more accurate estimates of demographic parameters, and explore adaptive divergence, potentially revolutionizing the way genetic data are used to manage wild populations. Here, we identified 10 944 single-nucleotide polymorphisms using restriction-site-associated DNA (RAD) sequencing to explore population structure, demography, and adaptive divergence in five populations of Chinook salmon (Oncorhynchus tshawytscha) from western Alaska. Patterns of population structure were similar to those of past studies, but our ability to assign individuals back to their region of origin was greatly improved (>90% accuracy for all populations). We also calculated effective size with and without removing physically linked loci identified from a linkage map, a novel method for nonmodel organisms. Estimates of effective size were generally above 1000 and were biased downward when physically linked loci were not removed. Outlier tests based on genetic differentiation identified 733 loci and three genomic regions under putative selection. These markers and genomic regions are excellent candidates for future research and can be used to create high-resolution panels for genetic monitoring and population assignment. This work demonstrates the utility of genomic data to inform conservation in highly exploited species with shallow population structure. PMID:24665338

  5. The density dilemma: limitations on juvenile production in threatened salmon populations

    USGS Publications Warehouse

    Walters, Annika W.; Copeland, Timothy; Venditti, David A.

    2013-01-01

    Density-dependent processes have repeatedly been shown to have a central role in salmonid population dynamics, but are often assumed to be negligible for populations at low abundances relative to historical records. Density dependence has been observed in overall spring/summer Snake River Chinook salmon Oncorhynchus tshawytscha production, but it is not clear how patterns observed at the aggregate level relate to individual populations within the basin. We used a Bayesian hierarchical modelling approach to explore the degree of density dependence in juvenile production for nine Idaho populations. Our results indicate that density dependence is ubiquitous, although its strength varies between populations. We also investigated the processes driving the population-level pattern and found density-dependent growth and mortality present for both common life-history strategies, but no evidence of density-dependent movement. Overwinter mortality, spatial clustering of redds and limited resource availability were identified as potentially important limiting factors contributing to density dependence. The ubiquity of density dependence for these threatened populations is alarming as stability at present low abundance levels suggests recovery may be difficult without major changes. We conclude that density dependence at the population level is common and must be considered in demographic analysis and management.

  6. Provenance matters: thermal reaction norms for embryo survival among sockeye salmon Oncorhynchus nerka populations.

    PubMed

    Whitney, C K; Hinch, S G; Patterson, D A

    2013-04-01

    Differences in thermal tolerance during embryonic development in Fraser River sockeye salmon Oncorhynchus nerka were examined among nine populations in a controlled common-garden incubation experiment. Forcing embryonic development at an extreme temperature (relative to current values) of 16° C, representing a future climate change scenario, significantly reduced survival compared to the more ecologically moderate temperature of 10° C (55% v. 93%). Survival at 14° C was intermediate between the other two temperatures (85%). More importantly, this survival response varied by provenance within and between temperature treatments. Thermal reaction norms showed an interacting response of genotype and environment (temperature), suggesting that populations of O. nerka may have adapted differentially to elevated temperatures during incubation and early development. Moreover, populations that historically experience warmer incubation temperatures at early development displayed a higher tolerance for warm temperatures. In contrast, thermal tolerance does not appear to transcend life stages as adult migration temperatures were not related to embryo thermal tolerance. The intra-population variation implies potential for thermal tolerance at the species level. The differential inter-population variation in thermal tolerance that was observed suggests, however, limited adaptive potential to thermal shifts for some populations. This infers that the intergenerational effects of increasing water temperatures may affect populations differentially, and that such thermally mediated adaptive selection may drive population, and therefore species, persistence. PMID:23557297

  7. WILD SALMON RESTORATION: IS IT WORTH IT?

    EPA Science Inventory

    Salmon are categorized biologically into two groups: Pacific salmon and Atlantic salmon. Atlantic salmon are found on both sides of the North Atlantic Ocean, but have declined precipitously compared to the size of runs prior to the 1700s. The largest (though small by historic ...

  8. The influence of population dynamics and environmental conditions on salmon re-colonization after large-scale distrubance

    NASA Astrophysics Data System (ADS)

    Pess, G. R.; Hilborn, R.; Kloehn, K.; Quinn, T.

    2010-12-01

    The transition from dispersal into unoccupied habitat to the establishment of a self-sustaining new population depends on the dynamics of the source and recipient populations, and the environmental conditions that facilitate or hinder exchange and successful reproduction. We used population growth rate, inter-annual variability estimates, habitat condition and size, hydrologic data, and an estimated dispersal effect to determine when colonizing pink salmon (Oncorhynchus gorbuscha) populations became self-sustaining after a long-term migration blockage (Hell’s Gate) was mitigated in the Fraser River, British Columbia, Canada. We used pink salmon spawning data from 1947 to 1987 in 66 streams to define populations, population growth rates, and the level of dispersal to newly accessible habitats. We also quantified the distance from source populations, the amount of newly accessible habitat, and determined whether stream flow conditions impeded fish passage at Hell’s Gate. Population dynamics models fit to observed data indicated that the combination of an initially large source population in the Fraser River below Hell’s Gate, high intrinsic growth rates linked to favorable climate-driven conditions, a constant supply of dispersers, and large amounts of newly available habitat resulted in the development of self-sustaining pink salmon populations in the Fraser River upstream of the historic barrier. Self-sustaining populations were developed within years of barrier removal and have continued to help expand the overall population of Fraser River pink salmon. However, not all locations had the same productivity and the magnitude of exchange among them was partly mediated by river conditions that permit or impede passage. Both re-colonized abundance levels were reduced and population spatial structure shifted relative to historic population abundance and spatial structure estimates.

  9. The Influence of Salmon Recolonization on Riparian Communities in the Cedar River, Washington, USA

    NASA Astrophysics Data System (ADS)

    Moravek, J.; Clipp, H.; Kiffney, P.

    2015-12-01

    Salmon are a valuable cultural and economic resource throughout the Pacific Northwest, but increasing human activity is degrading coastal ecosystems and threatening local salmon populations. Salmon conservation efforts often focus on habitat restoration, including the re-colonization of salmon into historically obstructed areas such as the Cedar River in Washington, USA. However, to assess the implications of salmon re-colonization on a landscape scale, it is critical to consider not only the river ecosystem but also the surrounding riparian habitat. Although prior studies suggest that salmon alter riparian food web dynamics, the riparian community on the Cedar River has not yet been characterized. To investigate possible connections between salmon and the riparian habitat, we surveyed riparian spider communities along a gradient of salmon inputs (g/m2). In 10-m transects along the banks of the river, we identified spiders and spider webs, collected prey from webs, and characterized nearby aquatic macroinvertebrate communities. We found that the density of aquatic macroinvertebrates, as well as the density of spider prey, both had significant positive relationships with salmon inputs, supporting the hypothesis that salmon provide energy and nutrients for both aquatic and riparian food webs. We also found that spider diversity significantly decreased with salmon inputs, potentially due to confounding factors such as stream gradient or vegetation structure. Although additional information is needed to fully understand this relationship, the significant connection between salmon inputs and spider diversity is compelling motivation for further studies regarding the link between aquatic and riparian systems on the Cedar River. Understanding the connections between salmon and the riparian community is critical to characterizing the landscape-scale implications of sustainable salmon management in the Pacific Northwest.

  10. Family size and effective population size in a hatchery stock of coho salmon (Oncorhynchus kisutch)

    USGS Publications Warehouse

    Simon, R.C.; McIntyre, J.D.; Hemmingsen, A.R.

    1986-01-01

    Means and variances of family size measured in five year-classes of wire-tagged coho salmon (Oncorhynchus kisutch) were linearly related. Population effective size was calculated by using estimated means and variances of family size in a 25-yr data set. Although numbers of age 3 adults returning to the hatchery appeared to be large enough to avoid inbreeding problems (the 25-yr mean exceeded 4500), the numbers actually contributing to the hatchery production may be too low. Several strategies are proposed to correct the problem perceived. Argument is given to support the contention that the problem of effective size is fairly general and is not confined to the present study population.

  11. Population level "flipperedness" in the eastern Pacific leatherback turtle.

    PubMed

    Sieg, Annette E; Zandonà, Eugenia; Izzo, Victor M; Paladino, Frank V; Spotila, James R

    2010-01-01

    Limb preference is a behavioral indicator of lateralized brain function that was recently elucidated experimentally in lower vertebrates. We assessed natural spontaneous limb use of nesting eastern Pacific leatherback turtles by recording which hindlimb flipper was extended overtop the cloaca to cover the egg chamber during oviposition. We found a population level right bias in 1889 observations of 361 individuals. This is the first report of a limb preference in Testudinata. PMID:19712702

  12. Spatial Heterogeneity in Shallow Streambed Water Temperatures, Copper River Delta, Alaska: Implications for Understanding Landscape-Scale Climate Change Impacts to Pacific Salmon Egg Incubation Rates

    NASA Astrophysics Data System (ADS)

    Adelfio, L. A.; Wondzell, S. M.; Reeves, G. H.; Mantua, N. J.

    2015-12-01

    Shallow streambed water temperature is a driving factor for Pacific salmon egg incubation. Small (1 to 2 oC) increases in incubation period water temperature may accelerate embryo development. We collected year-round water temperature data at 14 salmon spawning areas on the Copper River Delta (CRD), a 100 km wide coastal foreland in Southcentral Alaska. Our data show considerable temporal and spatial heterogeneity in shallow streambed water temperatures. Different water sources (precipitation vs. groundwater) and a spectrum of hydraulic conductivity and pressure head conditions were also observed. Landscape-scale patterns were not adequately characterized by typical watershed metrics including elevation, area, and slope. We found that catchment- and reach- scale geomorphology and surficial geology govern the surface-groundwater interactions that determine shallow streambed water temperature. The observed differences indicate that, across the CRD landscape, shallow streambed water temperature will not respond equally to projected climatic changes. Water temperature sensitivity to atmospheric conditions also varied by season, suggesting that year-round water temperature data are valuable for assessing potential climate change impacts to Pacific salmon in catchments where incubation period air temperatures are projected to exceed the freezing point with increasing frequency.

  13. Bioaccumulation of HCHs and DDTs in organs of Pacific salmon (genus Oncorhynchus) from the Sea of Okhotsk and the Bering Sea.

    PubMed

    Lukyanova, Olga N; Tsygankov, Vasiliy Yu; Boyarova, Margarita D; Khristoforova, Nadezhda K

    2016-08-01

    Concentrations of isomers of hexachlorocyclohexane (α-, β-, γ-HCH) and dichlorodiphenyltrichloroethane (DDT) and its metabolites (dichlorodiphenyldichloroethane (DDD) and dichlorodiphenyldichloroethylene (DDE) were assessed in organs of the pink (Oncorhynchus gorbuscha), chum (Oncorhynchus keta), chinook (Oncorhynchus tshawytscha), and sockeye salmon (Oncorhynchus nerka), caught near the Kuril Islands (the northern-western part of the Pacific Ocean), in the Sea of Okhotsk and the Bering Sea. Pesticides have been found to accumulate in fish organs in the following: muscles < liver < eggs < male gonads. The highest concentrations in muscles and liver have been recorded from sockeye. Of the DDT group, only DDE has been detected. The average concentration of HCHs + DDE in the muscles of pink, chum, chinook, and sockeye was 141, 125, 1241, 1641 ng/g lipids, respectively; and in the liver, 279, 183, 1305, 3805 ng/g lipids, respectively. The total concentration of HCHs isomers was higher than that of DDE. Average HCHs + DDE concentration in organs of salmon from study area is lower than that in salmon from Pacific coast of North America. PMID:27219293

  14. Population diversity in Pacific herring of the Puget Sound, USA.

    PubMed

    Siple, Margaret C; Francis, Tessa B

    2016-01-01

    Demographic, functional, or habitat diversity can confer stability on populations via portfolio effects (PEs) that integrate across multiple ecological responses and buffer against environmental impacts. The prevalence of these PEs in aquatic organisms is as yet unknown, and can be difficult to quantify; however, understanding mechanisms that stabilize populations in the face of environmental change is a key concern in ecology. Here, we examine PEs in Pacific herring (Clupea pallasii) in Puget Sound (USA) using a 40-year time series of biomass data for 19 distinct spawning population units collected using two survey types. Multivariate auto-regressive state-space models show independent dynamics among spawning subpopulations, suggesting that variation in herring production is partially driven by local effects at spawning grounds or during the earliest life history stages. This independence at the subpopulation level confers a stabilizing effect on the overall Puget Sound spawning stock, with herring being as much as three times more stable in the face of environmental perturbation than a single population unit of the same size. Herring populations within Puget Sound are highly asynchronous but share a common negative growth rate and may be influenced by the Pacific Decadal Oscillation. The biocomplexity in the herring stock shown here demonstrates that preserving spatial and demographic diversity can increase the stability of this herring population and its availability as a resource for consumers.

  15. Does among-population variation in burst swimming performance of sockeye salmon Oncorhynchus nerka fry reflect early life migrations?

    PubMed

    Sopinka, N M; Hinch, S G; Lotto, A G; Whitney, C K; Patterson, D A

    2013-11-01

    Using a fixed-speed test, burst swimming performance was found to vary among nine populations of emergent sockeye salmon Oncorhynchus nerka fry reared in a common-garden environment. No consistent relationship was, however, detected between difficulty of fry migration (upstream v. downstream) to rearing areas and total burst swimming duration or bursting rate. PMID:24117961

  16. Quantitative PCR analysis used to characterize physiological changes in brain tissue of senescent sockeye salmon.

    PubMed

    Storer, C S; Quinn, T P; Roberts, S B

    2013-10-01

    Senescence varies considerably among fishes, and understanding the evolutionary basis for this diversity has become an important area of study. For rapidly senescing species such as Pacific salmon, senescence is a complex process as these fish are initiating anorexia while migrating to natal spawning grounds, and die within days of reproduction. To better understand senescence in Pacific salmon we examined expression patterns for a suite of genes in brain tissue of pre-senescent and senescent sockeye salmon. Interestingly, a significant increase in expression of genes involved in telomere repair and immune activity was observed in senescent salmon. These data provide insight into physiological changes in salmon undergoing senescence and the factors contributing to variation in observed senescence rates among individuals and populations. PMID:23948798

  17. Genomic prediction in an admixed population of Atlantic salmon (Salmo salar)

    PubMed Central

    Ødegård, Jørgen; Moen, Thomas; Santi, Nina; Korsvoll, Sven A.; Kjøglum, Sissel; Meuwissen, Theo H. E.

    2014-01-01

    Reliability of genomic selection (GS) models was tested in an admixed population of Atlantic salmon, originating from crossing of several wild subpopulations. The models included ordinary genomic BLUP models (GBLUP), using genome-wide SNP markers of varying densities (1–220 k), a genomic identity-by-descent model (IBD-GS), using linkage analysis of sparse genome-wide markers, as well as a classical pedigree-based model. Reliabilities of the models were compared through 5-fold cross-validation. The traits studied were salmon lice (Lepeophtheirus salmonis) resistance (LR), measured as (log) density on the skin and fillet color (FC), with respective estimated heritabilities of 0.14 and 0.43. All genomic models outperformed the classical pedigree-based model, for both traits and at all marker densities. However, the relative improvement differed considerably between traits, models and marker densities. For the highly heritable FC, the IBD-GS had similar reliability as GBLUP at high marker densities (>22 k). In contrast, for the lowly heritable LR, IBD-GS was clearly inferior to GBLUP, irrespective of marker density. Hence, GBLUP was robust to marker density for the lowly heritable LR, but sensitive to marker density for the highly heritable FC. We hypothesize that this phenomenon may be explained by historical admixture of different founder populations, expected to reduce short-range lice density (LD) and induce long-range LD. The relative importance of LD/relationship information is expected to decrease/increase with increasing heritability of the trait. Still, using the ordinary GBLUP, the typical long-range LD of an admixed population may be effectively captured by sparse markers, while efficient utilization of relationship information may require denser markers (e.g., 22 k or more). PMID:25484890

  18. Genomic prediction in an admixed population of Atlantic salmon (Salmo salar).

    PubMed

    Odegård, Jørgen; Moen, Thomas; Santi, Nina; Korsvoll, Sven A; Kjøglum, Sissel; Meuwissen, Theo H E

    2014-01-01

    Reliability of genomic selection (GS) models was tested in an admixed population of Atlantic salmon, originating from crossing of several wild subpopulations. The models included ordinary genomic BLUP models (GBLUP), using genome-wide SNP markers of varying densities (1-220 k), a genomic identity-by-descent model (IBD-GS), using linkage analysis of sparse genome-wide markers, as well as a classical pedigree-based model. Reliabilities of the models were compared through 5-fold cross-validation. The traits studied were salmon lice (Lepeophtheirus salmonis) resistance (LR), measured as (log) density on the skin and fillet color (FC), with respective estimated heritabilities of 0.14 and 0.43. All genomic models outperformed the classical pedigree-based model, for both traits and at all marker densities. However, the relative improvement differed considerably between traits, models and marker densities. For the highly heritable FC, the IBD-GS had similar reliability as GBLUP at high marker densities (>22 k). In contrast, for the lowly heritable LR, IBD-GS was clearly inferior to GBLUP, irrespective of marker density. Hence, GBLUP was robust to marker density for the lowly heritable LR, but sensitive to marker density for the highly heritable FC. We hypothesize that this phenomenon may be explained by historical admixture of different founder populations, expected to reduce short-range lice density (LD) and induce long-range LD. The relative importance of LD/relationship information is expected to decrease/increase with increasing heritability of the trait. Still, using the ordinary GBLUP, the typical long-range LD of an admixed population may be effectively captured by sparse markers, while efficient utilization of relationship information may require denser markers (e.g., 22 k or more).

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

    USGS Publications Warehouse

    Benjamin, Joseph R.; Bellmore, James R.; Watson, Grace A.

    2016-01-01

    Marine derived nutrients delivered by large runs of returning salmon are thought to subsidize the in situ food resources that support juvenile salmon. In the Pacific Northwest, USA, salmon have declined to <10% of their historical abundance, with subsequent declines of marine derived nutrients once provided by large salmon runs. We explored whether low densities (<0.001 spawners/m2) of naturally spawning Chinook Salmon (Oncorhynchus tshawytscha) can affect ecosystem metabolism. We measured gross primary production (GPP) and ecosystem respiration (ER) continuously before, during, and after salmon spawning. We compared downstream reaches with low densities of spawning salmon to upstream reaches with fewer or no spawners in 3 mid-sized (4th-order) rivers in northern Washington. In addition, we measured chemical, physical, and biological factors that may be important in controlling rates of GPP and ER. We observed that low densities of spawning salmon can increase GPP by 46% during spawning, but values quickly return to those observed before spawning. No difference in ER was observed between up- and downstream reaches. Based on our results, salmon density, temperature, and the proximity to salmon redds were the most important factors controlling rates of GPP, whereas temperature was most important for ER. These results suggest that even at low spawning densities, salmon can stimulate basal resources that may propagate up the food web. Understanding how recipient ecosystems respond to low levels of marine derived nutrients may inform nutrient augmentation studies aimed at enhancing fish populations.

  20. Resource Requirements of the Pacific Leatherback Turtle Population

    PubMed Central

    Jones, T. Todd; Bostrom, Brian L.; Hastings, Mervin D.; Van Houtan, Kyle S.; Pauly, Daniel; Jones, David R.

    2012-01-01

    The Pacific population of leatherback sea turtles (Dermochelys coriacea) has drastically declined in the last 25 years. This decline has been linked to incidental capture by fisheries, egg and meat harvesting, and recently, to climate variability and resource limitation. Here we couple growth rates with feeding experiments and food intake functions to estimate daily energy requirements of leatherbacks throughout their development. We then estimate mortality rates from available data, enabling us to raise food intake (energy requirements) of the individual to the population level. We place energy requirements in context of available resources (i.e., gelatinous zooplankton abundance). Estimated consumption rates suggest that a single leatherback will eat upward of 1000 metric tonnes (t) of jellyfish in its lifetime (range 924–1112) with the Pacific population consuming 2.1×106 t of jellyfish annually (range 1.0–3.7×106) equivalent to 4.2×108 megajoules (MJ) (range 2.0–7.4×108). Model estimates suggest 2–7 yr-old juveniles comprise the majority of the Pacific leatherback population biomass and account for most of the jellyfish consumption (1.1×106 t of jellyfish or 2.2×108 MJ per year). Leatherbacks are large gelatinous zooplanktivores with consumption to biomass ratios of 96 (up to 192 if feeding strictly on low energy density Cnidarians); they, therefore, have a large capacity to impact gelatinous zooplankton landscapes. Understanding the leatherback's needs for gelatinous zooplankton, versus the availability of these resources, can help us better assess population trends and the influence of climate induced resource limitations to reproductive output. PMID:23071518

  1. Resource requirements of the Pacific leatherback turtle population.

    PubMed

    Jones, T Todd; Bostrom, Brian L; Hastings, Mervin D; Van Houtan, Kyle S; Pauly, Daniel; Jones, David R

    2012-01-01

    The Pacific population of leatherback sea turtles (Dermochelys coriacea) has drastically declined in the last 25 years. This decline has been linked to incidental capture by fisheries, egg and meat harvesting, and recently, to climate variability and resource limitation. Here we couple growth rates with feeding experiments and food intake functions to estimate daily energy requirements of leatherbacks throughout their development. We then estimate mortality rates from available data, enabling us to raise food intake (energy requirements) of the individual to the population level. We place energy requirements in context of available resources (i.e., gelatinous zooplankton abundance). Estimated consumption rates suggest that a single leatherback will eat upward of 1000 metric tonnes (t) of jellyfish in its lifetime (range 924-1112) with the Pacific population consuming 2.1×10(6) t of jellyfish annually (range 1.0-3.7×10(6)) equivalent to 4.2×10(8) megajoules (MJ) (range 2.0-7.4×10(8)). Model estimates suggest 2-7 yr-old juveniles comprise the majority of the Pacific leatherback population biomass and account for most of the jellyfish consumption (1.1×10(6) t of jellyfish or 2.2×10(8) MJ per year). Leatherbacks are large gelatinous zooplanktivores with consumption to biomass ratios of 96 (up to 192 if feeding strictly on low energy density Cnidarians); they, therefore, have a large capacity to impact gelatinous zooplankton landscapes. Understanding the leatherback's needs for gelatinous zooplankton, versus the availability of these resources, can help us better assess population trends and the influence of climate induced resource limitations to reproductive output. PMID:23071518

  2. Seasonality of vital events in a Pacific Island population.

    PubMed

    Underwood, J H

    1991-01-01

    Analyses of vital data derived from a family record register for the native population of Guam reveal significant variations in births, deaths, and marriages over the period 1901-41. Although lacking marked photoperiod or temperature changes of temperate zones, the tropical island is subject to marked seasonal differences in rainfall characteristic of western Pacific islands. Marital patterns exhibit troughs associated respectively with the Lenten period and with Christmas celebrations. Infant and childhood deaths show close correspondence with rainfall patterns, consistently exceeding expected values during the rainy season (July-November) when conditions are optimal for the spread of communicable and gastrointestinal diseases. Births attain a peak in November, or at the beginning of the more advantageous season for infant health and survival. Seasonality in vital events, reported for many Euroamerican and some African and Asian populations of modern and historical periods, has rarely been documented for native populations of the tropical Pacific. Comparisons of differences in these patterns among different populations in varied environments provide unique opportunities to evaluate causal models of interactions among biological, sociocultural, and physioenvironmental factors. PMID:1749959

  3. Seasonality of vital events in a Pacific Island population.

    PubMed

    Underwood, J H

    1991-01-01

    Analyses of vital data derived from a family record register for the native population of Guam reveal significant variations in births, deaths, and marriages over the period 1901-41. Although lacking marked photoperiod or temperature changes of temperate zones, the tropical island is subject to marked seasonal differences in rainfall characteristic of western Pacific islands. Marital patterns exhibit troughs associated respectively with the Lenten period and with Christmas celebrations. Infant and childhood deaths show close correspondence with rainfall patterns, consistently exceeding expected values during the rainy season (July-November) when conditions are optimal for the spread of communicable and gastrointestinal diseases. Births attain a peak in November, or at the beginning of the more advantageous season for infant health and survival. Seasonality in vital events, reported for many Euroamerican and some African and Asian populations of modern and historical periods, has rarely been documented for native populations of the tropical Pacific. Comparisons of differences in these patterns among different populations in varied environments provide unique opportunities to evaluate causal models of interactions among biological, sociocultural, and physioenvironmental factors.

  4. Temporal patterns in adult salmon migration timing across southeast Alaska.

    PubMed

    Kovach, Ryan P; Ellison, Stephen C; Pyare, Sanjay; Tallmon, David A

    2015-05-01

    Pacific salmon migration timing can drive population productivity, ecosystem dynamics, and human harvest. Nevertheless, little is known about long-term variation in salmon migration timing for multiple species across broad regions. We used long-term data for five Pacific salmon species throughout rapidly warming southeast Alaska to describe long-term changes in salmon migration timing, interannual phenological synchrony, relationships between climatic variation and migratory timing, and to test whether long-term changes in migration timing are related to glaciation in headwater streams. Temporal changes in the median date of salmon migration timing varied widely across species. Most sockeye populations are migrating later over time (11 of 14), but pink, chum, and especially coho populations are migrating earlier than they did historically (16 of 19 combined). Temporal trends in duration and interannual variation in migration timing were highly variable across species and populations. The greatest temporal shifts in the median date of migration timing were correlated with decreases in the duration of migration timing, suggestive of a loss of phenotypic variation due to natural selection. Pairwise interannual correlations in migration timing varied widely but were generally positive, providing evidence for weak region-wide phenological synchrony. This synchrony is likely a function of climatic variation, as interannual variation in migration timing was related to climatic phenomenon operating at large- (Pacific decadal oscillation), moderate- (sea surface temperature), and local-scales (precipitation). Surprisingly, the presence or the absence of glaciers within a watershed was unrelated to long-term shifts in phenology. Overall, there was extensive heterogeneity in long-term patterns of migration timing throughout this climatically and geographically complex region, highlighting that future climatic change will likely have widely divergent impacts on salmon

  5. Temporal patterns in adult salmon migration timing across southeast Alaska

    USGS Publications Warehouse

    Kovach, Ryan P.; Ellison, Stephen; Pyare, Sanjay; Tallmon, David

    2015-01-01

    Pacific salmon migration timing can drive population productivity, ecosystem dynamics, and human harvest. Nevertheless, little is known about long-term variation in salmon migration timing for multiple species across broad regions. We used long-term data for five Pacific salmon species throughout rapidly warming southeast Alaska to describe long-term changes in salmon migration timing, interannual phenological synchrony, relationships between climatic variation and migratory timing, and to test whether long-term changes in migration timing are related to glaciation in headwater streams. Temporal changes in the median date of salmon migration timing varied widely across species. Most sockeye populations are migrating later over time (11 of 14), but pink, chum, and especially coho populations are migrating earlier than they did historically (16 of 19 combined). Temporal trends in duration and interannual variation in migration timing were highly variable across species and populations. The greatest temporal shifts in the median date of migration timing were correlated with decreases in the duration of migration timing, suggestive of a loss of phenotypic variation due to natural selection. Pairwise interannual correlations in migration timing varied widely but were generally positive, providing evidence for weak region-wide phenological synchrony. This synchrony is likely a function of climatic variation, as interannual variation in migration timing was related to climatic phenomenon operating at large- (Pacific decadal oscillation), moderate- (sea surface temperature), and local-scales (precipitation). Surprisingly, the presence or the absence of glaciers within a watershed was unrelated to long-term shifts in phenology. Overall, there was extensive heterogeneity in long-term patterns of migration timing throughout this climatically and geographically complex region, highlighting that future climatic change will likely have widely divergent impacts on salmon

  6. Temporal patterns in adult salmon migration timing across southeast Alaska.

    PubMed

    Kovach, Ryan P; Ellison, Stephen C; Pyare, Sanjay; Tallmon, David A

    2015-05-01

    Pacific salmon migration timing can drive population productivity, ecosystem dynamics, and human harvest. Nevertheless, little is known about long-term variation in salmon migration timing for multiple species across broad regions. We used long-term data for five Pacific salmon species throughout rapidly warming southeast Alaska to describe long-term changes in salmon migration timing, interannual phenological synchrony, relationships between climatic variation and migratory timing, and to test whether long-term changes in migration timing are related to glaciation in headwater streams. Temporal changes in the median date of salmon migration timing varied widely across species. Most sockeye populations are migrating later over time (11 of 14), but pink, chum, and especially coho populations are migrating earlier than they did historically (16 of 19 combined). Temporal trends in duration and interannual variation in migration timing were highly variable across species and populations. The greatest temporal shifts in the median date of migration timing were correlated with decreases in the duration of migration timing, suggestive of a loss of phenotypic variation due to natural selection. Pairwise interannual correlations in migration timing varied widely but were generally positive, providing evidence for weak region-wide phenological synchrony. This synchrony is likely a function of climatic variation, as interannual variation in migration timing was related to climatic phenomenon operating at large- (Pacific decadal oscillation), moderate- (sea surface temperature), and local-scales (precipitation). Surprisingly, the presence or the absence of glaciers within a watershed was unrelated to long-term shifts in phenology. Overall, there was extensive heterogeneity in long-term patterns of migration timing throughout this climatically and geographically complex region, highlighting that future climatic change will likely have widely divergent impacts on salmon

  7. Comparison of genetic diversity in the recently founded Connecticut River Atlantic salmon population to that of its primary donor stock, Maine's Penobscot River

    USGS Publications Warehouse

    Spidle, A.P.; King, T.L.; Letcher, B.H.

    2004-01-01

    Anadromous Atlantic salmon returning to the Connecticut River (CR) from 1996 to 1999 were assayed for variability at nine microsatellite DNA loci. Heterozygosity and allele frequencies were compared to the anadromous Atlantic salmon returning to Maine's Penobscot River from 1998 to 2000. The Penobscot River was the primary source of the salmon used to found the previously extirpated population in the Connecticut River. While there were no significant differences in heterozygosity between the source population and the Connecticut River sea-run spawners, microsatellite allele frequencies were significantly different between the populations. Two techniques of estimating effective population size (Ne) suggested a healthy level of genetic variation in the Connecticut River population of anadromous Atlantic salmon. This is significant because the sea-run population is maintained almost entirely through hatchery production. Healthy ratios of Ne to N indicate that hatchery production has not resulted in excessive inbreeding to date. ?? 2003 Elsevier B.V. All rights reserved.

  8. Genomewide single nucleotide polymorphism discovery in Atlantic salmon (Salmo salar): validation in wild and farmed American and European populations.

    PubMed

    Yáñez, J M; Naswa, S; López, M E; Bassini, L; Correa, K; Gilbey, J; Bernatchez, L; Norris, A; Neira, R; Lhorente, J P; Schnable, P S; Newman, S; Mileham, A; Deeb, N; Di Genova, A; Maass, A

    2016-07-01

    A considerable number of single nucleotide polymorphisms (SNPs) are required to elucidate genotype-phenotype associations and determine the molecular basis of important traits. In this work, we carried out de novo SNP discovery accounting for both genome duplication and genetic variation from American and European salmon populations. A total of 9 736 473 nonredundant SNPs were identified across a set of 20 fish by whole-genome sequencing. After applying six bioinformatic filtering steps, 200 K SNPs were selected to develop an Affymetrix Axiom(®) myDesign Custom Array. This array was used to genotype 480 fish representing wild and farmed salmon from Europe, North America and Chile. A total of 159 099 (79.6%) SNPs were validated as high quality based on clustering properties. A total of 151 509 validated SNPs showed a unique position in the genome. When comparing these SNPs against 238 572 markers currently available in two other Atlantic salmon arrays, only 4.6% of the SNP overlapped with the panel developed in this study. This novel high-density SNP panel will be very useful for the dissection of economically and ecologically relevant traits, enhancing breeding programmes through genomic selection as well as supporting genetic studies in both wild and farmed populations of Atlantic salmon using high-resolution genomewide information. PMID:26849107

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

    PubMed

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

    2012-06-19

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

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

    PubMed

    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.

  11. The Between-Population Genetic Architecture of Growth, Maturation, and Plasticity in Atlantic Salmon

    PubMed Central

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

    2014-01-01

    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. PMID:24473933

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

    PubMed

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

    2011-11-01

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

  13. Chinook salmon foraging patterns in a changing Lake Michigan

    USGS Publications Warehouse

    Jacobs, Gregory R.; Madenjian, Charles P.; Bunnell, David B.; Warner, David M.; Claramunt, Randall M.

    2013-01-01

    Since Pacific salmon stocking began in Lake Michigan, managers have attempted to maintain salmon abundance at high levels within what can be sustained by available prey fishes, primarily Alewife Alosa pseudoharengus. Chinook Salmon Oncorhynchus tshawytscha are the primary apex predators in pelagic Lake Michigan and patterns in their prey selection (by species and size) may strongly influence pelagic prey fish communities in any given year. In 1994–1996, there were larger Alewives, relatively more abundant alternative prey species, fewer Chinook Salmon, and fewer invasive species in Lake Michigan than in 2009–2010. The years 2009–2010 were instead characterized by smaller, leaner Alewives, fewer alternative prey species, higher abundance of Chinook Salmon, a firmly established nonnative benthic community, and reduced abundance of Diporeia, an important food of Lake Michigan prey fish. We characterized Chinook Salmon diets, prey species selectivity, and prey size selectivity between 1994–1996 and 2009–2010 time periods. In 1994–1996, Alewife as prey represented a smaller percentage of Chinook Salmon diets than in 2009–2010, when alewife comprised over 90% of Chinook Salmon diets, possibly due to declines in alternative prey fish populations. The size of Alewives eaten by Chinook Salmon also decreased between these two time periods. For the largest Chinook Salmon in 2009–2010, the average size of Alewife prey was nearly 50 mm total length shorter than in 1994–1996. We suggest that changes in the Lake Michigan food web, such as the decline in Diporeia, may have contributed to the relatively low abundance of large Alewives during the late 2000s by heightening the effect of predation from top predators like Chinook Salmon, which have retained a preference for Alewife and now forage with greater frequency on smaller Alewives.

  14. Latitudinal variation in population structure of wintering Pacific Black Brant

    USGS Publications Warehouse

    Schamber, J.L.; Sedinger, J.S.; Ward, D.H.; Hagmeier, K.R.

    2007-01-01

    Latitudinal variation in population structure during the winter has been reported in many migratory birds, but has been documented in few species of waterfowl. Variation in environmental and social conditions at wintering sites can potentially influence the population dynamics of differential migrants. We examined latitudinal variation in sex and age classes of wintering Pacific Black Brant (Branta bernicla nigricans). Brant are distributed along a wide latitudinal gradient from Alaska to Mexico during the winter. Accordingly, migration distances for brant using different wintering locations are highly variable and winter settlement patterns are likely associated with a spatially variable food resource. We used resightings of brant banded in southwestern Alaska to examine sex and age ratios of birds wintering at Boundary Bay in British Columbia, and at San Quintin Bay, Ojo de Liebre Lagoon, and San Ignacio Lagoon in Baja California from 1998 to 2000. Sex ratios were similar among wintering locations for adults and were consistent with the mating strategy of geese. The distribution of juveniles varied among wintering areas, with greater proportions of juveniles observed at northern (San Quintin Bay and Ojo de Liebre Lagoon) than at southern (San Ignacio Lagoon) locations in Baja California. We suggest that age-related variation in the winter distribution of Pacific Black Brant is mediated by variation in productivity among individuals at different wintering locations and by social interactions among wintering family groups.

  15. Genetic Monitoring and Evaluation Program for Supplemented Populations of Salmon and Steelhead in the Snake River Basin, 1990-1991 Annual Report.

    SciTech Connect

    Waples, Robin S.; Teel, David J.; Aebersold, Paul B.

    1991-08-01

    This is the first report of research for an ongoing study to evaluate the genetic effects of using hatchery-reared fish to supplement natural populations of chinook salmon and steelhead in the Snake River Basin.

  16. Analyzing large-scale conservation interventions with Bayesian hierarchical models: a case study of supplementing threatened Pacific salmon.

    PubMed

    Scheuerell, Mark D; Buhle, Eric R; Semmens, Brice X; Ford, Michael J; Cooney, Tom; Carmichael, Richard W

    2015-05-01

    Myriad human activities increasingly threaten the existence of many species. A variety of conservation interventions such as habitat restoration, protected areas, and captive breeding have been used to prevent extinctions. Evaluating the effectiveness of these interventions requires appropriate statistical methods, given the quantity and quality of available data. Historically, analysis of variance has been used with some form of predetermined before-after control-impact design to estimate the effects of large-scale experiments or conservation interventions. However, ad hoc retrospective study designs or the presence of random effects at multiple scales may preclude the use of these tools. We evaluated the effects of a large-scale supplementation program on the density of adult Chinook salmon Oncorhynchus tshawytscha from the Snake River basin in the northwestern United States currently listed under the U.S. Endangered Species Act. We analyzed 43 years of data from 22 populations, accounting for random effects across time and space using a form of Bayesian hierarchical time-series model common in analyses of financial markets. We found that varying degrees of supplementation over a period of 25 years increased the density of natural-origin adults, on average, by 0-8% relative to nonsupplementation years. Thirty-nine of the 43 year effects were at least two times larger in magnitude than the mean supplementation effect, suggesting common environmental variables play a more important role in driving interannual variability in adult density. Additional residual variation in density varied considerably across the region, but there was no systematic difference between supplemented and reference populations. Our results demonstrate the power of hierarchical Bayesian models to detect the diffuse effects of management interventions and to quantitatively describe the variability of intervention success. Nevertheless, our study could not address whether ecological factors

  17. Analyzing large-scale conservation interventions with Bayesian hierarchical models: a case study of supplementing threatened Pacific salmon.

    PubMed

    Scheuerell, Mark D; Buhle, Eric R; Semmens, Brice X; Ford, Michael J; Cooney, Tom; Carmichael, Richard W

    2015-05-01

    Myriad human activities increasingly threaten the existence of many species. A variety of conservation interventions such as habitat restoration, protected areas, and captive breeding have been used to prevent extinctions. Evaluating the effectiveness of these interventions requires appropriate statistical methods, given the quantity and quality of available data. Historically, analysis of variance has been used with some form of predetermined before-after control-impact design to estimate the effects of large-scale experiments or conservation interventions. However, ad hoc retrospective study designs or the presence of random effects at multiple scales may preclude the use of these tools. We evaluated the effects of a large-scale supplementation program on the density of adult Chinook salmon Oncorhynchus tshawytscha from the Snake River basin in the northwestern United States currently listed under the U.S. Endangered Species Act. We analyzed 43 years of data from 22 populations, accounting for random effects across time and space using a form of Bayesian hierarchical time-series model common in analyses of financial markets. We found that varying degrees of supplementation over a period of 25 years increased the density of natural-origin adults, on average, by 0-8% relative to nonsupplementation years. Thirty-nine of the 43 year effects were at least two times larger in magnitude than the mean supplementation effect, suggesting common environmental variables play a more important role in driving interannual variability in adult density. Additional residual variation in density varied considerably across the region, but there was no systematic difference between supplemented and reference populations. Our results demonstrate the power of hierarchical Bayesian models to detect the diffuse effects of management interventions and to quantitatively describe the variability of intervention success. Nevertheless, our study could not address whether ecological factors

  18. Analyzing large-scale conservation interventions with Bayesian hierarchical models: a case study of supplementing threatened Pacific salmon

    PubMed Central

    Scheuerell, Mark D; Buhle, Eric R; Semmens, Brice X; Ford, Michael J; Cooney, Tom; Carmichael, Richard W

    2015-01-01

    Myriad human activities increasingly threaten the existence of many species. A variety of conservation interventions such as habitat restoration, protected areas, and captive breeding have been used to prevent extinctions. Evaluating the effectiveness of these interventions requires appropriate statistical methods, given the quantity and quality of available data. Historically, analysis of variance has been used with some form of predetermined before-after control-impact design to estimate the effects of large-scale experiments or conservation interventions. However, ad hoc retrospective study designs or the presence of random effects at multiple scales may preclude the use of these tools. We evaluated the effects of a large-scale supplementation program on the density of adult Chinook salmon Oncorhynchus tshawytscha from the Snake River basin in the northwestern United States currently listed under the U.S. Endangered Species Act. We analyzed 43 years of data from 22 populations, accounting for random effects across time and space using a form of Bayesian hierarchical time-series model common in analyses of financial markets. We found that varying degrees of supplementation over a period of 25 years increased the density of natural-origin adults, on average, by 0–8% relative to nonsupplementation years. Thirty-nine of the 43 year effects were at least two times larger in magnitude than the mean supplementation effect, suggesting common environmental variables play a more important role in driving interannual variability in adult density. Additional residual variation in density varied considerably across the region, but there was no systematic difference between supplemented and reference populations. Our results demonstrate the power of hierarchical Bayesian models to detect the diffuse effects of management interventions and to quantitatively describe the variability of intervention success. Nevertheless, our study could not address whether ecological

  19. 1992 Columbia River Salmon Flow Measures Options Analysis/EIS.

    SciTech Connect

    Not Available

    1992-01-01

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

  20. Costs of climate change: Economic value of Yakima River salmon

    SciTech Connect

    Anderson, D.M.; Shankle, S.A.; Scott, M.J.; Neitzel, D.A.; Chatters, J.C.

    1992-07-01

    This work resulted from a continuing multidisciplinary analysis of species preservation and global change. The paper explores the economic cost of a potential regional warming as it affects one Pacific Northwest natural resource, the spring chinook salmon (Oncorhynchus tshcawytscha). Climate change and planned habitat improvements impact the production and economic value of soling chinook salmon of the Yakima River tributary of the Columbia River in eastern Washington. The paper presents a derivation of the total economic value of a chinook salmon, which includes the summation of the existence, commercial, recreational, and capital values of the fish. When currently available commercial, recreational, existence, and capital values for chinook salmon were applied to estimated population changes, the estimated change in the economic value per fish associated with reduction of one fish run proved significant.

  1. Comparing effects of transmitters within and among populations: application to swimming performance of juvenile Chinook salmon

    USGS Publications Warehouse

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

    2013-01-01

    The sensitivity of fish to a transmitter depends on factors such as environmental conditions, fish morphology, life stage, rearing history, and tag design. However, synthesizing general trends across studies is difficult because each study focuses on a particular performance measure, species, life stage, and transmitter model. These differences motivated us to develop simple metrics that allow effects of transmitters to be compared among different species, populations, or studies. First, we describe how multiple regression analysis can be used to quantify the effect of tag burden (transmitter mass relative to fish mass) on measures of physiological performance. Next, we illustrate how the slope and intercept parameters can be used to calculate two summary statistics: θ, which estimates the tag burden threshold above which the performance of tagged fish begins to decline relative to untagged fish; and k, which measures the percentage change in performance per percentage point increase in tag burden. When θ = 0, k provides a single measure of the tag's effect that can be compared among species, populations, or studies. We apply this analysis to two different experiments that measure the critical swimming speed (U crit) of tagged juvenile Chinook Salmon Oncorhynchus tshawytscha. In both experiments, U crit declined as tag burden increased, but we found no significant threshold in swimming performance. Estimates of θ ranged from −0.6% to 2.1% among six unique treatment groups, indicating that swimming performance began to decline at a relatively low tag burden. Estimates of k revealed that U crit of tagged fish declined by −2.68% to −4.86% for each 1% increase in tag burden. Both θ and k varied with the tag's antenna configuration, tag implantation method, and posttagging recovery time. Our analytical approach can be used to gain insights across populations to better understand factors affecting the ability of fish to carry a transmitter.

  2. Genetic stock identification of immature chum salmon ( Oncorhynchus keta) in the western Bering Sea, 2004

    NASA Astrophysics Data System (ADS)

    Kang, Minho; Kim, Suam; Low, Loh-Lee

    2016-03-01

    Genetic stock identification studies have been widely applied to Pacific salmon species to estimate stock composition of complex mixed-stock fisheries. In a September-October 2004 survey, 739 chum salmon ( Oncorhynchus keta) specimens were collected from 23 stations in the western Bering Sea. We determined the genetic stock composition of immature chum salmon based on the previous mitochondria DNA baseline. Each regional estimate was computed based on the conditional maximum likelihood method using 1,000 bootstrap resampling and then pooled to the major regional groups: Korea - Japan - Primorie (KJP) / Russia (RU) / Northwest Alaska (NWA) / Alaska Peninsula - Southcentral Alaska - Southeast Alaska - British Columbia - Washington (ONA). The stock composition of immature chum salmon in the western Bering Sea was a mix of 0.424 KJP, 0.421 RU, 0.116 NWA, and 0.039 ONA stocks. During the study period, the contribution of Asian chum salmon stocks gradually changed from RU to KJP stock. In addition, North American populations from NWA and ONA were small but present near the vicinity of the Russian coast and the Commander Islands, suggesting that the study areas in the western Bering Sea were an important migration route for Pacific chum salmon originating both from Asia and North America during the months of September and October. These results make it possible to better understand the chum salmon stock composition of the mixed-stock fisheries in the western Bering Sea and the stock-specific distribution pattern of chum salmon on the high-seas.

  3. Immunization of pacific salmon: comparison of intraperitoneal injection and hyperosmotic infiltration of Vibrio anguillarum and Aeromonas salmonicida bacterins

    USGS Publications Warehouse

    Antipa, Ross; Amend, Donald F.

    1977-01-01

    Two methods of immunizing fish, intraperitoneal (i.p.) injection and hyperosmotic infiltration, were compared for control of vibriosis and furunculosis in pen-reared coho salmon (Oncorhynchus kisutch) and chinook salmon (O. tshawytscha). Both methods provided significant protection against vibriosis under field test conditions. In coho salmon, hyperosmotic infiltration provided the best protection and fastest rise in antibody titer of seven treatments tested. In chinook salmon, hyperosmotic infiltration of Vibrio anguillarum and Aeromonas salmonicida vaccines resulted in 83.3% survival in comparison with 28.7% survival in controls. Both i.p. injection and hyperosmotic infiltration of V. anguillarum and A. salmonicida bacterins resulted in production of serum antibodies specific for each respective pathogen. Vaccination with bivalent V. anguillarum–A.salmonicida vaccines produced antibodies to both pathogens, and provided protection against vibriosis. Growth rates of vaccinated coho salmon were not significantly different from controls.

  4. Oil spill impact on Pacific salmon (g. Oncorhynchus) of northwestern Sakhalin (Tengi River Basin as a pattern)

    NASA Astrophysics Data System (ADS)

    Ivanov, Alexander N.; Tarasov, Nikolay N.; Pusankov, Konstantin L.; Ivanova, Lubov V.; Pusankova, Ekaterina N.

    2001-01-01

    Northern Sakhalin is a region of the intensive oil and gas transportation by oil-pipe lines. In July 2, 1997, the oil spill has happened at the oil-pipe line 'Okha-Komsomolsk-on- Amur.' Oil pollution spread over the basin of Tengi Rive (Amur estuary). The Tengi River is a spawning area for endemic and important commercial fish. There is a reserve on the river. Genus Oncorhynchus (pink and chum salmon) prevail in ichthyofauna. A satellite data analysis (NOAA-12, NOAA-14) was a success to accurate the oil distribution over the Amur estuary. As a result of the accident, more than 120 t of oil have been spilled. 26.3 km of the river area, more than 60 km of the Amur estuary coast and about 850 km2 of its water area were polluted. In the basin of Tengi River about 58000 m2 of spawning area were lost. The main damage (89%) was caused to the fry feeding near the coast. The loss of fish production has constituted about 1800 t. By species the damage was as follows: 53% -- pink salmon, 29% -- chum salmon, 11% -- masu salmon and 7% -- coho salmon.

  5. Protectiveness of water quality criteria for copper in western United States waters relative to predicted olfactory responses in juvenile Pacific salmon.

    PubMed

    DeForest, David K; Gensemer, Robert W; Van Genderen, Eric J; Gorsuch, Joseph W

    2011-07-01

    Copper (Cu) can impair olfaction in juvenile Pacific salmon (as well as other fishes), thus potentially inhibiting the ability of juveniles to avoid predators or to find food. Because Cu is commonly elevated in stormwater runoff in urban environments, storm events may result in elevated Cu concentrations in salmon-bearing streams. Accordingly, there is concern that existing Cu criteria, which were not derived using data for olfactory-related endpoints, may not be adequately protective of juvenile salmon. However, a modification of the US Environmental Protection Agency (USEPA) biotic ligand model (BLM) for deriving site-specific Cu criteria was recently proposed, which accounted for the sensitivity of olfactory endpoints. The modification was based on olfactory inhibition in juvenile coho salmon (Oncorhynchus kisutch) exposed to Cu in various combinations of pH, hardness, alkalinity, and dissolved organic carbon (DOC) concentrations. We used that olfactory-based BLM to derive 20% inhibition concentrations (IC20) values for Cu for 133 stream locations in the western United States. The olfactory BLM-based IC20 values were compared to the existing hardness-based Cu criteria and the USEPA's BLM-based Cu criteria for these representative natural waters of the western United States. Of the 133 sampling locations, mean hardness-dependent acute and chronic Cu criteria were below the mean olfactory-based BLM IC20 value in 122 (92%) and 129 (97%) of the waters, respectively (i.e., <20% olfactory impairment would have been predicted at the mean hardness-based Cu criteria concentrations). Waters characterized by a combination of high hardness and very low DOC were most likely to have hardness-based Cu criteria that were higher than the olfactory-based BLM IC20 values, because DOC strongly influences Cu bioavailability in the BLM. In all waters, the USEPA's current BLM-based criteria were below the mean olfactory-based BLM IC20 values, indicating that the USEPA's BLM

  6. Population Viability of the Snake River Chinook Salmon (Oncorhynchus Tshawytscha) : Recovery Issues for Threatened and Endangered Snake River Salmon : Technical Report 11 of 11.

    SciTech Connect

    Emlen, John Merritt

    1993-06-01

    A stochastic simulation model of spring chinook population dynamics was parameterized using 36 years of redd count data from five index streams on the middle fork of the Salmon River in Idaho. Two versions of the model, one in which spawning age structure was presumed to follow an evolutionarily stable strategy and another in which spawning age structure was constrained to observed values were examined. The models were then used to generate 1000 statistically representative population projections over the next 100 years to assess risk of extinction and prospects for stock rebuilding. Current levels of production and mortality appear to suffice for maintaining the status quo, virtually assuring persistence over the next 100 years, barring catastophes, but providing no hope for rebuilding. A doubling of the current population level over the next 100 years can be expected to follow an increase in {alpha} (density independent mortality or fry production) of 5 to 25%, but rebuilding to the population levels prevailing in the 1950`s will require an increase in {alpha} of at least 37%.

  7. Cardiorespiratory performance and blood chemistry during swimming and recovery in three populations of elite swimmers: Adult sockeye salmon.

    PubMed

    Eliason, Erika J; Clark, Timothy D; Hinch, Scott G; Farrell, Anthony P

    2013-10-01

    Every year, millions of adult sockeye salmon (Oncorhynchus nerka) perform an arduous, once-in-a-lifetime migration up the Fraser River (BC, Canada) to return to their natal stream to spawn. The changes in heart rate, stroke volume, and arterio-venous oxygen extraction (i.e., factors determining rates of oxygen delivery to the tissues by the cardiovascular system) have never been directly and simultaneously measured along with whole animal oxygen uptake in a maximally swimming fish. Here, such measurements were made using three sockeye salmon populations (Early Stuart, Chilko and Quesnel), which each performed two consecutive critical swimming speed (Ucrit) challenges to provide a comprehensive quantification of cardiovascular physiology, oxygen status and blood chemistry associated with swimming and recovery. Swim performance, oxygen uptake, cardiac output, heart rate and stroke volume did not significantly vary at rest, during swimming or during recovery between populations or sexes. Despite incomplete metabolic recovery between swim challenges, all fish repeated their swim performance and similar quantitative changes in the cardiorespiratory variables were observed for each swim challenge. The high maximum cardiorespiratory performance and excellent repeat swim performance are clearly beneficial in allowing the salmon to maintain steady ground speeds and reach the distant spawning grounds in a timely manner. PMID:23880060

  8. Cardiorespiratory performance and blood chemistry during swimming and recovery in three populations of elite swimmers: Adult sockeye salmon.

    PubMed

    Eliason, Erika J; Clark, Timothy D; Hinch, Scott G; Farrell, Anthony P

    2013-10-01

    Every year, millions of adult sockeye salmon (Oncorhynchus nerka) perform an arduous, once-in-a-lifetime migration up the Fraser River (BC, Canada) to return to their natal stream to spawn. The changes in heart rate, stroke volume, and arterio-venous oxygen extraction (i.e., factors determining rates of oxygen delivery to the tissues by the cardiovascular system) have never been directly and simultaneously measured along with whole animal oxygen uptake in a maximally swimming fish. Here, such measurements were made using three sockeye salmon populations (Early Stuart, Chilko and Quesnel), which each performed two consecutive critical swimming speed (Ucrit) challenges to provide a comprehensive quantification of cardiovascular physiology, oxygen status and blood chemistry associated with swimming and recovery. Swim performance, oxygen uptake, cardiac output, heart rate and stroke volume did not significantly vary at rest, during swimming or during recovery between populations or sexes. Despite incomplete metabolic recovery between swim challenges, all fish repeated their swim performance and similar quantitative changes in the cardiorespiratory variables were observed for each swim challenge. The high maximum cardiorespiratory performance and excellent repeat swim performance are clearly beneficial in allowing the salmon to maintain steady ground speeds and reach the distant spawning grounds in a timely manner.

  9. Synchronous centennial-scale variability in abundance of remote sardine populations in the Pacific

    NASA Astrophysics Data System (ADS)

    Kuwae, M.; Takashige, S.; Yamamoto, M.; Sagawa, T.; Takeoka, H.

    2012-12-01

    A number of studies have identified evidence for connections between Pacific climate decadal variability and variations in Pacific marine ecosystems which are typically shown in abundance of remote sardine and anchovy species off Japan, California, Peru, and Chile as well as Alaska salmon species. The variations in climate indices and abundance of sardine and anchovy species most likely have 50-70 year cycles and therefore these natural perturbations in climates and Pacific ecosystems should be considered for developing predictive models of fisheries productions and the managements. Despite the importance of natural perturbations for long-term predictions, one issue, whether synchronous centennial-variations in remote Pacific fisheries productions in response to climate variability exists in the past, has not been questioned, because there has never been long-term reconstructed time series in the western North Pacific. Here we present well preserved, fossil fish scale-based abundance record of Japanese sardine over the last 1100 years reconstructed from a seasonal anoxic basin in the western Seto Inland Sea near their spawning areas in the western North Pacific. A comparison of our record with other previous records clearly showed centennial-scale variations in abundance of sardine species off Japan, California, and Chile, characterized by centennial-scale alternations between low abundance regimes and high abundance regimes in which multidecadal fluctuations with large amplitudes occurred once or several times. High abundance regimes from 1450 to 1650 AD and after 1800 AD and a low abundance regime from 1650 to 1800 AD corresponded to low frequency patterns of PDO index reconstructed from tree-ring records in North America. This indicates that connections between Pacific climate variability and variations in Pacific marine ecosystems exist not only on multidecadal timescales but on centennial timescales. Three to four hundred-yr periodicity of the Pacific climate

  10. Projected impacts of climate change on salmon habitat restoration.

    PubMed

    Battin, James; Wiley, Matthew W; Ruckelshaus, Mary H; Palmer, Richard N; Korb, Elizabeth; Bartz, Krista K; Imaki, Hiroo

    2007-04-17

    Throughout the world, efforts are under way to restore watersheds, but restoration planning rarely accounts for future climate change. Using a series of linked models of climate, land cover, hydrology, and salmon population dynamics, we investigated the impacts of climate change on the effectiveness of proposed habitat restoration efforts designed to recover depleted Chinook salmon populations in a Pacific Northwest river basin. Model results indicate a large negative impact of climate change on freshwater salmon habitat. Habitat restoration and protection can help to mitigate these effects and may allow populations to increase in the face of climate change. The habitat deterioration associated with climate change will, however, make salmon recovery targets much more difficult to attain. Because the negative impacts of climate change in this basin are projected to be most pronounced in relatively pristine, high-elevation streams where little restoration is possible, climate change and habitat restoration together are likely to cause a spatial shift in salmon abundance. River basins that span the current snow line appear especially vulnerable to climate change, and salmon recovery plans that enhance lower-elevation habitats are likely to be more successful over the next 50 years than those that target the higher-elevation basins likely to experience the greatest snow-rain transition.

  11. Projected impacts of climate change on salmon habitat restoration

    PubMed Central

    Battin, James; Wiley, Matthew W.; Ruckelshaus, Mary H.; Palmer, Richard N.; Korb, Elizabeth; Bartz, Krista K.; Imaki, Hiroo

    2007-01-01

    Throughout the world, efforts are under way to restore watersheds, but restoration planning rarely accounts for future climate change. Using a series of linked models of climate, land cover, hydrology, and salmon population dynamics, we investigated the impacts of climate change on the effectiveness of proposed habitat restoration efforts designed to recover depleted Chinook salmon populations in a Pacific Northwest river basin. Model results indicate a large negative impact of climate change on freshwater salmon habitat. Habitat restoration and protection can help to mitigate these effects and may allow populations to increase in the face of climate change. The habitat deterioration associated with climate change will, however, make salmon recovery targets much more difficult to attain. Because the negative impacts of climate change in this basin are projected to be most pronounced in relatively pristine, high-elevation streams where little restoration is possible, climate change and habitat restoration together are likely to cause a spatial shift in salmon abundance. River basins that span the current snow line appear especially vulnerable to climate change, and salmon recovery plans that enhance lower-elevation habitats are likely to be more successful over the next 50 years than those that target the higher-elevation basins likely to experience the greatest snow–rain transition. PMID:17412830

  12. The needs of salmon and steelhead in balancing their conservation and use

    USGS Publications Warehouse

    Burger, C.V.; Knudsen, E.E.; Steward, C.R.; MacDonald, D.D.; Williams, J.E.; Reiser, D.W.

    2000-01-01

    Over the past 100 years, Pacific salmon Oncorhynchus spp. and steelhead trout O. mykiss populations in the Pacific Northwest have experienced dramatic declines as a result of human population growth and associated development of the regioni??s natural resources. Any strategy to reverse those declines will depend on achieving consensus among a diverse group of stakeholders willing to (1) restore damaged habitats and watersheds; (2) consider the biological needs of salmonid fishes; and (3) understand, conserve, and manage existing levels of biodiversity within an ecosystem context. The objective of this chapter is to review and summarize the needs of Pacific salmon and steelhead trout from perspectives that promote their sustainability and perpetuity, and, within that context, provide a framework, for the development of a sustainable fisheries strategy. Although volumes of information are available on the life histories and habitat requirements of Pacific salmonids, new concepts have begun to address the importance of habitat complexity, genetic diversity among locally adapted populations, and the need for appropriate units of conservation. Habitat variability and complexity are the templates that produce diverse, locally adapted populations of Pacific salmon and steelhead trout. Molded by conditions in the environments they colonized, salmon and steelhead have unique adaptations they may have taken hundred i?? perhaps thousands i?? of years to evolve. Any strategy to reverse the declines of salmon and steelhead must focus on conserving both current levels of genetic diversity as well as restoration and maintenance of habitats compatible with the specific needs of individual populations. An argument can be made that we know enough already about the needs of our salmon and steelhead to allow us to make appropriate decisions. There is strong need to integrate what we know about local salmonid adaptations and habitat needs with conservation and management strategies

  13. Changes in the genetic structure of Atlantic salmon populations over four decades reveal substantial impacts of stocking and potential resiliency

    PubMed Central

    Perrier, Charles; Guyomard, René; Bagliniere, Jean-Luc; Nikolic, Natacha; Evanno, Guillaume

    2013-01-01

    While the stocking of captive-bred fish has been occurring for decades and has had substantial immediate genetic and evolutionary impacts on wild populations, its long-term consequences have only been weakly investigated. Here, we conducted a spatiotemporal analysis of 1428 Atlantic salmon sampled from 1965 to 2006 in 25 populations throughout France to investigate the influence of stocking on the neutral genetic structure in wild Atlantic salmon (Salmo salar) populations. On the basis of the analysis of 11 microsatellite loci, we found that the overall genetic structure among populations dramatically decreased over the period studied. Admixture rates among populations were highly variable, ranging from a nearly undetectable contribution from donor stocks to total replacement of the native gene pool, suggesting extremely variable impacts of stocking. Depending on population, admixture rates either increased, remained stable, or decreased in samples collected between 1998 and 2006 compared to samples from 1965 to 1987, suggesting either rising, long-lasting or short-term impacts of stocking. We discuss the potential mechanisms contributing to this variability, including the reduced fitness of stocked fish and persistence of wild locally adapted individuals. PMID:23919174

  14. From the South Pacific: experiences in the development of instructional materials in population education in the Pacific.

    PubMed

    1984-01-01

    The population education program in the Pacific was established in 1980, a decade behind that in Asia. Some countries produced materials on population. Fiji produced excellent student and teacher guides, and the Marshall Islands conducted a workshop to develop curriculum materials for use in elementary schools and in an adult education program. In the Solomon Islands 10 modules on population education will be used in the "core" subject for all 1st year students of the new College of Higher Education. Of these 10 modules, 5 have been completed. Because other Pacific countries had not moved further from their plans of developing curriculum and instructional materials in this field a workshop was conducted during September 1983 to provide training in the development of population education materials. The workshop was aimed at preparing guidelines for the development of in-school and out-of-school curricula and sample instructional materials and developing prototype materials which can be adopted by the Pacific countries. While there may be many materials in population education developed in Asia which can be used in the Pacific, it was deemed helpful to have prototype instructional materials for the Pacific region developed by the Pacific islandes themselves. The following guidelines were suggested: stress the unfiqueness of the Pacific; emphasize culture and traditional lifestyle; use local examples; focus on the interrelationships of population factors; employ local or regional resources, materials, and expertise; and stay sensitive to what is aceptable in population education. The major work of developing draft prototype curricula and sample instructional materials was done by the participants in 2 teams, 1 for the in-school and the other for the out-of-school program. The in-school group developed sample units instead of sample lessons in population edcuation for social science, science, mathematics, environmental science, and home economics for the secondary

  15. Major histocompatibility complex diversity is positively associated with stream water temperatures in proximate populations of sockeye salmon.

    PubMed

    Larson, W A; Lisi, P J; Seeb, J E; Seeb, L W; Schindler, D E

    2016-09-01

    Local adaptation to heterogeneous environments generates population diversity within species, significantly increasing ecosystem stability and flows of ecosystem services. However, few studies have isolated the specific mechanisms that create and maintain this diversity. Here, we examined the relationship between water temperature in streams used for spawning and genetic diversity at a gene involved in immune function [the major histocompatibility complex (MHC)] in 14 populations of sockeye salmon (Oncorhynchus nerka) sampled across the Wood River basin in south-western Alaska. The largest influence on MHC diversity was lake basin, but we also found a significant positive correlation between average water temperature and MHC diversity. This positive relationship between temperature and MHC diversity appears to have been produced by natural selection at very local scales rather than neutral processes, as no correlation was observed between temperature and genetic diversity at 90 neutral markers. Additionally, no significant relationship was observed between temperature variability and MHC diversity. Although lake basin was the largest driver of differences in MHC diversity, our results also demonstrate that fine-scale differences in water temperature may generate variable selection regimes in populations that spawn in habitats separated by as little as 1 km. Additionally, our results indicated that some populations may be reaching a maximum level of MHC diversity. We postulate that salmon from populations in warm streams may delay spawning until late summer to avoid thermal stress as well as the elevated levels of pathogen prevalence and virulence associated with warm temperatures earlier in the summer.

  16. Major histocompatibility complex diversity is positively associated with stream water temperatures in proximate populations of sockeye salmon.

    PubMed

    Larson, W A; Lisi, P J; Seeb, J E; Seeb, L W; Schindler, D E

    2016-09-01

    Local adaptation to heterogeneous environments generates population diversity within species, significantly increasing ecosystem stability and flows of ecosystem services. However, few studies have isolated the specific mechanisms that create and maintain this diversity. Here, we examined the relationship between water temperature in streams used for spawning and genetic diversity at a gene involved in immune function [the major histocompatibility complex (MHC)] in 14 populations of sockeye salmon (Oncorhynchus nerka) sampled across the Wood River basin in south-western Alaska. The largest influence on MHC diversity was lake basin, but we also found a significant positive correlation between average water temperature and MHC diversity. This positive relationship between temperature and MHC diversity appears to have been produced by natural selection at very local scales rather than neutral processes, as no correlation was observed between temperature and genetic diversity at 90 neutral markers. Additionally, no significant relationship was observed between temperature variability and MHC diversity. Although lake basin was the largest driver of differences in MHC diversity, our results also demonstrate that fine-scale differences in water temperature may generate variable selection regimes in populations that spawn in habitats separated by as little as 1 km. Additionally, our results indicated that some populations may be reaching a maximum level of MHC diversity. We postulate that salmon from populations in warm streams may delay spawning until late summer to avoid thermal stress as well as the elevated levels of pathogen prevalence and virulence associated with warm temperatures earlier in the summer. PMID:27341174

  17. Re-creating missing population baselines for Pacific reef sharks.

    PubMed

    Nadon, Marc O; Baum, Julia K; Williams, Ivor D; McPherson, Jana M; Zgliczynski, Brian J; Richards, Benjamin L; Schroeder, Robert E; Brainard, Russell E

    2012-06-01

    Sharks and other large predators are scarce on most coral reefs, but studies of their historical ecology provide qualitative evidence that predators were once numerous in these ecosystems. Quantifying density of sharks in the absence of humans (baseline) is, however, hindered by a paucity of pertinent time-series data. Recently researchers have used underwater visual surveys, primarily of limited spatial extent or nonstandard design, to infer negative associations between reef shark abundance and human populations. We analyzed data from 1607 towed-diver surveys (>1 ha transects surveyed by observers towed behind a boat) conducted at 46 reefs in the central-western Pacific Ocean, reefs that included some of the world's most pristine coral reefs. Estimates of shark density from towed-diver surveys were substantially lower (<10%) than published estimates from surveys along small transects (<0.02 ha), which is not consistent with inverted biomass pyramids (predator biomass greater than prey biomass) reported by other researchers for pristine reefs. We examined the relation between the density of reef sharks observed in towed-diver surveys and human population in models that accounted for the influence of oceanic primary productivity, sea surface temperature, reef area, and reef physical complexity. We used these models to estimate the density of sharks in the absence of humans. Densities of gray reef sharks (Carcharhinus amblyrhynchos), whitetip reef sharks (Triaenodon obesus), and the group "all reef sharks" increased substantially as human population decreased and as primary productivity and minimum sea surface temperature (or reef area, which was highly correlated with temperature) increased. Simulated baseline densities of reef sharks under the absence of humans were 1.1-2.4/ha for the main Hawaiian Islands, 1.2-2.4/ha for inhabited islands of American Samoa, and 0.9-2.1/ha for inhabited islands in the Mariana Archipelago, which suggests that density of reef sharks

  18. Association between geomorphic attributes of watersheds, water temperature, and salmon spawn timing in Alaskan streams

    NASA Astrophysics Data System (ADS)

    Lisi, Peter J.; Schindler, Daniel E.; Bentley, Kale T.; Pess, George R.

    2013-03-01

    Intraspecific variation in the seasonal reproductive timing of Pacific salmon (Oncorhynchus sp.) has important implications for the resilience of salmon and for organisms in freshwater and terrestrial communities that depend on salmon resources. Stream temperature has well known associations with salmon spawn timing but how stream and watershed geomorphology relates to the variation in salmon spawn timing is less understood. We used multivariate statistics applied to five environmental variables to compare conditions across 36 watersheds in the Wood River basin in southwest Alaska. We found that the environmental conditions in the first two axes of a principal components analysis (PCA) explained 76% of the variation in summer temperature among streams and 45% of the variation in spawn timing of sockeye salmon. The average habitat characteristics of streams that characterized three spawn timing groups of sockeye salmon were significantly distinct from one another. Sites supporting early spawning populations tend to have steeper and smaller watersheds, while late spawning populations occur in streams draining large, lower gradient watersheds with lakes in the drainage network. Finally, we show that stream temperature and spawn timing among streams have little spatial correlation across the landscape, thereby producing a fine-scale mosaic of spawn timing across the river basin. These results demonstrate that geomorphology and hydrology interact to produce a heterogeneous thermal template for natural selection to influence salmon spawn timing across river basins.

  19. Pacific salmonines in the Great Lakes Basin

    USGS Publications Warehouse

    Claramunt, Randall M.; Madenjian, Charles P.; Clapp, David; Taylor, William W.; Lynch, Abigail J.; Leonard, Nancy J.

    2012-01-01

    Pacific salmon (genus Oncorhynchus) are a valuable resource, both within their native range in the North Pacific rim and in the Great Lakes basin. Understanding their value from a biological and economic perspective in the Great Lakes, however, requires an understanding of changes in the ecosystem and of management actions that have been taken to promote system stability, integrity, and sustainable fisheries. Pacific salmonine introductions to the Great Lakes are comprised mainly of Chinook salmon, coho salmon, and steelhead and have accounted for 421, 177, and 247 million fish, respectively, stocked during 1966-2007. Stocking of Pacific salmonines has been effective in substantially reducing exotic prey fish abundances in several of the Great Lakes (e.g., lakes Michigan, Huron, and Ontario). The goal of our evaluation was to highlight differences in management strategies and perspectives across the basin, and to evaluate policies for Pacific salmonine management in the Great Lakes. Currently, a potential conflict exists between Pacific salmonine management and native fish rehabilitation goals because of the desire to sustain recreational fisheries and to develop self-sustaining populations of stocked Pacific salmonines in the Great Lakes. We provide evidence that suggests Pacific salmonines have not only become naturalized to the food webs of the Great Lakes, but that their populations (specifically Chinook salmon) may be fluctuating in concert with specific prey (i.e., alewives) whose populations are changing relative to environmental conditions and ecosystem disturbances. Remaining questions, however, are whether or not “natural” fluctuations in predator and prey provide enough “stability” in the Great Lakes food webs, and even more importantly, would a choice by managers to attempt to reduce the severity of predator-prey oscillations be antagonistic to native fish restoration efforts. We argue that, on each of the Great Lakes, managers are pursuing

  20. Saving the Salmon

    ERIC Educational Resources Information Center

    Sprangers, Donald

    2004-01-01

    In November 2000, wild Atlantic salmon were placed under the protection of the Endangered Species Act of 1973. Washington Academy (WA) in Maine has played an integral role in the education and restoration of this species. Efforts to restore the salmon's dwindling population, enhance critical habitat areas, and educate and inform the public require…

  1. Recreational anglers' attitudes, beliefs, and behaviors related to catch-and-release practices of Pacific salmon in British Columbia.

    PubMed

    Nguyen, Vivian M; Rudd, Murray A; Hinch, Scott G; Cooke, Steven J

    2013-10-15

    The fate of captured and released fish in recreational fisheries depends in large part on fisher handling and behavior. As such, there is a need for promoting adoption of responsible fishing practices. We interviewed recreational sockeye salmon anglers in the lower Fraser River, British Columbia, to assess their awareness of responsible fishing practices and identify gaps where improved education could promote conservation-oriented behaviors. Based on our interview data, we developed three latent class models of salmon angler typologies based on: 1) anglers' fishing behaviors and preferences, 2) anglers' perceived risks to salmon survival due to post-capture live release, and 3) anglers' level of support for education programs. In the first model, we identified salmon-only anglers (33% of sample), lake-species specialists (46%), and all-around anglers (21%). These classes were differentiated primarily by non-salmon fishing activities (e.g., other target species). In the second model, we found four classes of anglers who differed with regards to key factors they thought affected post-release survival: air exposure (39% of sample); water temperature (24%); hook location (22%); and revival effort (15%). In the third model, we found anglers were either supporters (73%) or non-supporters (27%) of angler education programs. Heterogeneity existed among anglers but we found no correlations in angler classes across models, nor any significant demographic or experiential predictors of class membership. Respondents generally had high awareness and application of catch-and-release best practices, with lake-species specialists rating a higher awareness and usage of recommended catch-and-release technique, and were significantly more likely to cut the line on deeply hooked fish than other groups. Our findings provide resource managers with important insight into the attitudes and behaviors of sockeye salmon anglers in the important lower Fraser River recreational fishery. Our

  2. Recreational anglers' attitudes, beliefs, and behaviors related to catch-and-release practices of Pacific salmon in British Columbia.

    PubMed

    Nguyen, Vivian M; Rudd, Murray A; Hinch, Scott G; Cooke, Steven J

    2013-10-15

    The fate of captured and released fish in recreational fisheries depends in large part on fisher handling and behavior. As such, there is a need for promoting adoption of responsible fishing practices. We interviewed recreational sockeye salmon anglers in the lower Fraser River, British Columbia, to assess their awareness of responsible fishing practices and identify gaps where improved education could promote conservation-oriented behaviors. Based on our interview data, we developed three latent class models of salmon angler typologies based on: 1) anglers' fishing behaviors and preferences, 2) anglers' perceived risks to salmon survival due to post-capture live release, and 3) anglers' level of support for education programs. In the first model, we identified salmon-only anglers (33% of sample), lake-species specialists (46%), and all-around anglers (21%). These classes were differentiated primarily by non-salmon fishing activities (e.g., other target species). In the second model, we found four classes of anglers who differed with regards to key factors they thought affected post-release survival: air exposure (39% of sample); water temperature (24%); hook location (22%); and revival effort (15%). In the third model, we found anglers were either supporters (73%) or non-supporters (27%) of angler education programs. Heterogeneity existed among anglers but we found no correlations in angler classes across models, nor any significant demographic or experiential predictors of class membership. Respondents generally had high awareness and application of catch-and-release best practices, with lake-species specialists rating a higher awareness and usage of recommended catch-and-release technique, and were significantly more likely to cut the line on deeply hooked fish than other groups. Our findings provide resource managers with important insight into the attitudes and behaviors of sockeye salmon anglers in the important lower Fraser River recreational fishery. Our

  3. Pacific Lamprey Research and Restoration : Annual Report 1997.

    SciTech Connect

    Jackson, Aaron D.; Hatch, Douglas R.; Close, David A.

    1998-08-05

    The once abundant stocks of Pacific lamprey (Lampetra tridentata) above Bonneville Dam are currently depressed (Close et al. 1995). It is likely that many of the same factors that led to the decline of wild stocks of Columbia River Pacific salmon and steelhead have impacted Pacific lamprey populations as well. The Pacific Lamprey Research and Restoration Project, funded by Bonneville Power Administration, is a cooperative effort between the Confederated Tribes of the Umatilla Indian Reservation, the Columbia River Inter-Tribal Fish Commission, and Oregon State University with the goal to increase Pacific lamprey stocks above Bonneville Dam.

  4. Genetic isolation between the Western and Eastern Pacific populations of pronghorn spiny lobster Panulirus penicillatus.

    PubMed

    Chow, Seinen; Jeffs, Andrew; Miyake, Yoichi; Konishi, Kooichi; Okazaki, Makoto; Suzuki, Nobuaki; Abdullah, Muhamad F; Imai, Hideyuki; Wakabayasi, Toshie; Sakai, Mitsuo

    2011-01-01

    The pronghorn spiny lobster, Panulirus penicillatus, is a circumtropical species which has the widest global distribution among all the species of spiny lobster, ranging throughout the entire Indo-Pacific region. Partial nucleotide sequences of mitochondrial DNA COI (1,142-1,207 bp) and 16S rDNA (535-546 bp) regions were determined for adult and phyllosoma larval samples collected from the Eastern Pacific (EP)(Galápagos Islands and its adjacent water), Central Pacific (CP)(Hawaii and Tuamotu) and the Western Pacific (WP)(Japan, Indonesia, Fiji, New Caledonia and Australia). Phylogenetic analyses revealed two distinct large clades corresponding to the geographic origin of samples (EP and CP+WP). No haplotype was shared between the two regional samples, and average nucleotide sequence divergence (Kimura's two parameter distance) between EP and CP+WP samples was 3.8±0.5% for COI and 1.0±0.4% for 16S rDNA, both of which were much larger than those within samples. The present results indicate that the Pacific population of the pronghorn spiny lobster is subdivided into two distinct populations (Eastern Pacific and Central to Western Pacific), with no gene flow between them. Although the pronghorn spiny lobster have long-lived teleplanic larvae, the vast expanse of Pacific Ocean with no islands and no shallow substrate which is known as the East Pacific Barrier appears to have isolated these two populations for a long time (c.a. 1MY).

  5. Genetic stock identification of sockeye and chum salmon from Bristol Bay, alaska. Final report

    SciTech Connect

    Wilmot, R.L.; Everett, R.J.; Gellman, W.A.

    1989-06-01

    To study the Pacific salmon that may be affected by oil and gas development in the North Aleutian Basin, Alaska, electrophoretic methods of protein separation were used to genetically characterize stocks. In 1987, tissue samples were collected from eleven populations of sockeye salmon and four populations of chum salmon from Bristol Bay drainages. In the laboratory, 50 gene loci from each collection were analyzed to establish genetic baseline data. In comparisons to sockeye salmon sampled from the same drainages in previous years, no significant differences in allele frequencies were found. The genetic identities (Nei) amoung Bristol Bay sockeye salmon populations are high. Few loci are variable, and only 2% of the total genetic variation is due to differences between populations. Bristol Bay chum salmon sampled have genetic identities of 0.97 or more. Divergence between chum stocks, at 4%, is twice that of sockeye salmon sampled. Computer simuations with maximum-likelihood statistics and re-sampling procedures were used to estimate the composition of artificial mixed stocks made up from baseline data.

  6. Hydrologic Alterations from Climate Change Inform Assessment of Ecological Risk to Pacific Salmon in Bristol Bay, Alaska.

    PubMed

    Wobus, Cameron; Prucha, Robert; Albert, David; Woll, Christine; Loinaz, Maria; Jones, Russell; Travers, Constance

    2015-01-01

    We developed an integrated hydrologic model of the upper Nushagak and Kvichak watersheds in the Bristol Bay region of southwestern Alaska, a region under substantial development pressure from large-scale copper mining. We incorporated climate change scenarios into this model to evaluate how hydrologic regimes and stream temperatures might change in a future climate, and to summarize indicators of hydrologic alteration that are relevant to salmon habitat ecology and life history. Model simulations project substantial changes in mean winter flow, peak flow dates, and water temperature by 2100. In particular, we find that annual hydrographs will no longer be dominated by a single spring thaw event, but will instead be characterized by numerous high flow events throughout the winter. Stream temperatures increase in all future scenarios, although these temperature increases are moderated relative to air temperatures by cool baseflow inputs during the summer months. Projected changes to flow and stream temperature could influence salmon through alterations in the suitability of spawning gravels, changes in the duration of incubation, increased growth during juvenile stages, and increased exposure to chronic and acute temperature stress. These climate-modulated changes represent a shifting baseline in salmon habitat quality and quantity in the future, and an important consideration to adequately assess the types and magnitude of risks associated with proposed large-scale mining in the region.

  7. Hydrologic Alterations from Climate Change Inform Assessment of Ecological Risk to Pacific Salmon in Bristol Bay, Alaska

    PubMed Central

    Wobus, Cameron; Prucha, Robert; Albert, David; Woll, Christine; Loinaz, Maria; Jones, Russell

    2015-01-01

    We developed an integrated hydrologic model of the upper Nushagak and Kvichak watersheds in the Bristol Bay region of southwestern Alaska, a region under substantial development pressure from large-scale copper mining. We incorporated climate change scenarios into this model to evaluate how hydrologic regimes and stream temperatures might change in a future climate, and to summarize indicators of hydrologic alteration that are relevant to salmon habitat ecology and life history. Model simulations project substantial changes in mean winter flow, peak flow dates, and water temperature by 2100. In particular, we find that annual hydrographs will no longer be dominated by a single spring thaw event, but will instead be characterized by numerous high flow events throughout the winter. Stream temperatures increase in all future scenarios, although these temperature increases are moderated relative to air temperatures by cool baseflow inputs during the summer months. Projected changes to flow and stream temperature could influence salmon through alterations in the suitability of spawning gravels, changes in the duration of incubation, increased growth during juvenile stages, and increased exposure to chronic and acute temperature stress. These climate-modulated changes represent a shifting baseline in salmon habitat quality and quantity in the future, and an important consideration to adequately assess the types and magnitude of risks associated with proposed large-scale mining in the region. PMID:26645380

  8. Hydrologic Alterations from Climate Change Inform Assessment of Ecological Risk to Pacific Salmon in Bristol Bay, Alaska.

    PubMed

    Wobus, Cameron; Prucha, Robert; Albert, David; Woll, Christine; Loinaz, Maria; Jones, Russell; Travers, Constance

    2015-01-01

    We developed an integrated hydrologic model of the upper Nushagak and Kvichak watersheds in the Bristol Bay region of southwestern Alaska, a region under substantial development pressure from large-scale copper mining. We incorporated climate change scenarios into this model to evaluate how hydrologic regimes and stream temperatures might change in a future climate, and to summarize indicators of hydrologic alteration that are relevant to salmon habitat ecology and life history. Model simulations project substantial changes in mean winter flow, peak flow dates, and water temperature by 2100. In particular, we find that annual hydrographs will no longer be dominated by a single spring thaw event, but will instead be characterized by numerous high flow events throughout the winter. Stream temperatures increase in all future scenarios, although these temperature increases are moderated relative to air temperatures by cool baseflow inputs during the summer months. Projected changes to flow and stream temperature could influence salmon through alterations in the suitability of spawning gravels, changes in the duration of incubation, increased growth during juvenile stages, and increased exposure to chronic and acute temperature stress. These climate-modulated changes represent a shifting baseline in salmon habitat quality and quantity in the future, and an important consideration to adequately assess the types and magnitude of risks associated with proposed large-scale mining in the region. PMID:26645380

  9. Using Grizzly Bears to Assess Harvest-Ecosystem Tradeoffs in Salmon Fisheries

    PubMed Central

    MacDuffee, Misty; Mangel, Marc; Paquet, Paul; Wilmers, Christopher C.

    2012-01-01

    Implementation of ecosystem-based fisheries management (EBFM) requires a clear conceptual and quantitative framework for assessing how different harvest options can modify benefits to ecosystem and human beneficiaries. We address this social-ecological need for Pacific salmon fisheries, which are economically valuable but intercept much of the annual pulse of nutrient subsidies that salmon provide to terrestrial and aquatic food webs. We used grizzly bears, vectors of salmon nutrients and animals with densities strongly coupled to salmon abundance, as surrogates for “salmon ecosystem” function. Combining salmon biomass and stock-recruitment data with stable isotope analysis, we assess potential tradeoffs between fishery yields and bear population densities for six sockeye salmon stocks in Bristol Bay, Alaska, and British Columbia (BC), Canada. For the coastal stocks, we find that both bear densities and fishery yields would increase substantially if ecosystem allocations of salmon increase from currently applied lower to upper goals and beyond. This aligning of benefits comes at a potential cost, however, with the possibility of forgoing harvests in low productivity years. In contrast, we detect acute tradeoffs between bear densities and fishery yields in interior stocks within the Fraser River, BC, where biomass from other salmon species is low. There, increasing salmon allocations to ecosystems would benefit threatened bear populations at the cost of reduced long-term yields. To resolve this conflict, we propose an EBFM goal that values fisheries and bears (and by extension, the ecosystem) equally. At such targets, ecosystem benefits are unexpectedly large compared with losses in fishery yields. To explore other management options, we generate tradeoff curves that provide stock-specific accounting of the expected loss to fishers and gain to bears as more salmon escape the fishery. Our approach, modified to suit multiple scenarios, provides a generalizable

  10. Using grizzly bears to assess harvest-ecosystem tradeoffs in salmon fisheries.

    PubMed

    Levi, Taal; Darimont, Chris T; Macduffee, Misty; Mangel, Marc; Paquet, Paul; Wilmers, Christopher C

    2012-01-01

    Implementation of ecosystem-based fisheries management (EBFM) requires a clear conceptual and quantitative framework for assessing how different harvest options can modify benefits to ecosystem and human beneficiaries. We address this social-ecological need for Pacific salmon fisheries, which are economically valuable but intercept much of the annual pulse of nutrient subsidies that salmon provide to terrestrial and aquatic food webs. We used grizzly bears, vectors of salmon nutrients and animals with densities strongly coupled to salmon abundance, as surrogates for "salmon ecosystem" function. Combining salmon biomass and stock-recruitment data with stable isotope analysis, we assess potential tradeoffs between fishery yields and bear population densities for six sockeye salmon stocks in Bristol Bay, Alaska, and British Columbia (BC), Canada. For the coastal stocks, we find that both bear densities and fishery yields would increase substantially if ecosystem allocations of salmon increase from currently applied lower to upper goals and beyond. This aligning of benefits comes at a potential cost, however, with the possibility of forgoing harvests in low productivity years. In contrast, we detect acute tradeoffs between bear densities and fishery yields in interior stocks within the Fraser River, BC, where biomass from other salmon species is low. There, increasing salmon allocations to ecosystems would benefit threatened bear populations at the cost of reduced long-term yields. To resolve this conflict, we propose an EBFM goal that values fisheries and bears (and by extension, the ecosystem) equally. At such targets, ecosystem benefits are unexpectedly large compared with losses in fishery yields. To explore other management options, we generate tradeoff curves that provide stock-specific accounting of the expected loss to fishers and gain to bears as more salmon escape the fishery. Our approach, modified to suit multiple scenarios, provides a generalizable method

  11. Using grizzly bears to assess harvest-ecosystem tradeoffs in salmon fisheries.

    PubMed

    Levi, Taal; Darimont, Chris T; Macduffee, Misty; Mangel, Marc; Paquet, Paul; Wilmers, Christopher C

    2012-01-01

    Implementation of ecosystem-based fisheries management (EBFM) requires a clear conceptual and quantitative framework for assessing how different harvest options can modify benefits to ecosystem and human beneficiaries. We address this social-ecological need for Pacific salmon fisheries, which are economically valuable but intercept much of the annual pulse of nutrient subsidies that salmon provide to terrestrial and aquatic food webs. We used grizzly bears, vectors of salmon nutrients and animals with densities strongly coupled to salmon abundance, as surrogates for "salmon ecosystem" function. Combining salmon biomass and stock-recruitment data with stable isotope analysis, we assess potential tradeoffs between fishery yields and bear population densities for six sockeye salmon stocks in Bristol Bay, Alaska, and British Columbia (BC), Canada. For the coastal stocks, we find that both bear densities and fishery yields would increase substantially if ecosystem allocations of salmon increase from currently applied lower to upper goals and beyond. This aligning of benefits comes at a potential cost, however, with the possibility of forgoing harvests in low productivity years. In contrast, we detect acute tradeoffs between bear densities and fishery yields in interior stocks within the Fraser River, BC, where biomass from other salmon species is low. There, increasing salmon allocations to ecosystems would benefit threatened bear populations at the cost of reduced long-term yields. To resolve this conflict, we propose an EBFM goal that values fisheries and bears (and by extension, the ecosystem) equally. At such targets, ecosystem benefits are unexpectedly large compared with losses in fishery yields. To explore other management options, we generate tradeoff curves that provide stock-specific accounting of the expected loss to fishers and gain to bears as more salmon escape the fishery. Our approach, modified to suit multiple scenarios, provides a generalizable method

  12. Original observations of Desmozoon lepeophtherii, a microsporidian hyperparasite infecting the salmon louse Lepeophtheirus salmonis, and its subsequent detection by other researchers

    PubMed Central

    2011-01-01

    A microsporidian hyperparasite, Desmozoon lepeophtherii, of the parasitic copepod Lepeophtheirus salmonis (salmon louse), infecting farmed Atlantic salmon (Salmo salar), was first discovered in the west of Scotland in 2000. Heavily infected salmon lice are easily recognised as they have large opaque inclusions distributed throughout the body. The prevalence of salmon lice with visible signs of microsporidiosis can be up to 10% of the population from certain farm sites. The microsporidian was also isolated from the host Atlantic salmon suggesting it may have a two host life cycle. The authors believe that the infection in immunocompetent salmon may be latent, becoming acute during periods of infection with another pathogen or during sexual maturation. Since its first discovery in Scotland, Desmozoon lepeophtherii has been subsequently reported from Norway, and more recently from the Pacific coast of North America. PMID:22166354

  13. Original observations of Desmozoon lepeophtherii, a microsporidian hyperparasite infecting the salmon louse Lepeophtheirus salmonis, and its subsequent detection by other researchers.

    PubMed

    Freeman, Mark A; Sommerville, Christina

    2011-12-13

    A microsporidian hyperparasite, Desmozoon lepeophtherii, of the parasitic copepod Lepeophtheirus salmonis (salmon louse), infecting farmed Atlantic salmon (Salmo salar), was first discovered in the west of Scotland in 2000. Heavily infected salmon lice are easily recognised as they have large opaque inclusions distributed throughout the body. The prevalence of salmon lice with visible signs of microsporidiosis can be up to 10% of the population from certain farm sites. The microsporidian was also isolated from the host Atlantic salmon suggesting it may have a two host life cycle. The authors believe that the infection in immunocompetent salmon may be latent, becoming acute during periods of infection with another pathogen or during sexual maturation. Since its first discovery in Scotland, Desmozoon lepeophtherii has been subsequently reported from Norway, and more recently from the Pacific coast of North America.

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

    USGS Publications Warehouse

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

    2015-01-01

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

  15. A critical assessment of the ecological assumptions underpinning compensatory mitigation of salmon-derived nutrients

    USGS Publications Warehouse

    Collins, Scott F.; Marcarelli, Amy M.; Baxter, Colden V.; Wipfli, Mark S.

    2015-01-01

    We critically evaluate some of the key ecological assumptions underpinning the use of nutrient replacement as a means of recovering salmon populations and a range of other organisms thought to be linked to productive salmon runs. These assumptions include: (1) nutrient mitigation mimics the ecological roles of salmon, (2) mitigation is needed to replace salmon-derived nutrients and stimulate primary and invertebrate production in streams, and (3) food resources in rearing habitats limit populations of salmon and resident fishes. First, we call into question assumption one because an array of evidence points to the multi-faceted role played by spawning salmon, including disturbance via redd-building, nutrient recycling by live fish, and consumption by terrestrial consumers. Second, we show that assumption two may require qualification based upon a more complete understanding of nutrient cycling and productivity in streams. Third, we evaluate the empirical evidence supporting food limitation of fish populations and conclude it has been only weakly tested. On the basis of this assessment, we urge caution in the application of nutrient mitigation as a management tool. Although applications of nutrients and other materials intended to mitigate for lost or diminished runs of Pacific salmon may trigger ecological responses within treated ecosystems, contributions of these activities toward actual mitigation may be limited.

  16. A Critical Assessment of the Ecological Assumptions Underpinning Compensatory Mitigation of Salmon-Derived Nutrients.

    PubMed

    Collins, Scott F; Marcarelli, Amy M; Baxter, Colden V; Wipfli, Mark S

    2015-09-01

    We critically evaluate some of the key ecological assumptions underpinning the use of nutrient replacement as a means of recovering salmon populations and a range of other organisms thought to be linked to productive salmon runs. These assumptions include: (1) nutrient mitigation mimics the ecological roles of salmon, (2) mitigation is needed to replace salmon-derived nutrients and stimulate primary and invertebrate production in streams, and (3) food resources in rearing habitats limit populations of salmon and resident fishes. First, we call into question assumption one because an array of evidence points to the multi-faceted role played by spawning salmon, including disturbance via redd-building, nutrient recycling by live fish, and consumption by terrestrial consumers. Second, we show that assumption two may require qualification based upon a more complete understanding of nutrient cycling and productivity in streams. Third, we evaluate the empirical evidence supporting food limitation of fish populations and conclude it has been only weakly tested. On the basis of this assessment, we urge caution in the application of nutrient mitigation as a management tool. Although applications of nutrients and other materials intended to mitigate for lost or diminished runs of Pacific salmon may trigger ecological responses within treated ecosystems, contributions of these activities toward actual mitigation may be limited.

  17. A Critical Assessment of the Ecological Assumptions Underpinning Compensatory Mitigation of Salmon-Derived Nutrients

    NASA Astrophysics Data System (ADS)

    Collins, Scott F.; Marcarelli, Amy M.; Baxter, Colden V.; Wipfli, Mark S.

    2015-09-01

    We critically evaluate some of the key ecological assumptions underpinning the use of nutrient replacement as a means of recovering salmon populations and a range of other organisms thought to be linked to productive salmon runs. These assumptions include: (1) nutrient mitigation mimics the ecological roles of salmon, (2) mitigation is needed to replace salmon-derived nutrients and stimulate primary and invertebrate production in streams, and (3) food resources in rearing habitats limit populations of salmon and resident fishes. First, we call into question assumption one because an array of evidence points to the multi-faceted role played by spawning salmon, including disturbance via redd-building, nutrient recycling by live fish, and consumption by terrestrial consumers. Second, we show that assumption two may require qualification based upon a more complete understanding of nutrient cycling and productivity in streams. Third, we evaluate the empirical evidence supporting food limitation of fish populations and conclude it has been only weakly tested. On the basis of this assessment, we urge caution in the application of nutrient mitigation as a management tool. Although applications of nutrients and other materials intended to mitigate for lost or diminished runs of Pacific salmon may trigger ecological responses within treated ecosystems, contributions of these activities toward actual mitigation may be limited.

  18. Blue whale population structure along the eastern South Pacific Ocean: evidence of more than one population.

    PubMed

    Torres-Florez, J P; Hucke-Gaete, R; LeDuc, R; Lang, A; Taylor, B; Pimper, L E; Bedriñana-Romano, L; Rosenbaum, H C; Figueroa, C C

    2014-12-01

    Blue whales (Balaenoptera musculus) were among the most intensively exploited species of whales in the world. As a consequence of this intense exploitation, blue whale sightings off the coast of Chile were uncommon by the end of the 20th century. In 2004, a feeding and nursing ground was reported in southern Chile (SCh). With the aim to investigate the genetic identity and relationship of these Chilean blue whales to those in other Southern Hemisphere areas, 60 biopsy samples were collected from blue whales in SCh between 2003 and 2009. These samples were genotyped at seven microsatellite loci and the mitochondrial control region was sequenced, allowing us to identify 52 individuals. To investigate the genetic identity of this suspected remnant population, we compared these 52 individuals to blue whales from Antarctica (ANT, n = 96), Northern Chile (NCh, n = 19) and the eastern tropical Pacific (ETP, n = 31). No significant differentiation in haplotype frequencies (mtDNA) or among genotypes (nDNA) was found between SCh, NCh and ETP, while significant differences were found between those three areas and Antarctica for both the mitochondrial and microsatellite analyses. Our results suggest at least two breeding population units or subspecies exist, which is also supported by other lines of evidence such as morphometrics and acoustics. The lack of differences detected between SCh/NCh/ETP areas supports the hypothesis that eastern South Pacific blue whales are using the ETP area as a possible breeding area. Considering the small population sizes previously reported for the SCh area, additional conservation measures and monitoring of this population should be developed and prioritized. PMID:25492593

  19. Blue whale population structure along the eastern South Pacific Ocean: evidence of more than one population.

    PubMed

    Torres-Florez, J P; Hucke-Gaete, R; LeDuc, R; Lang, A; Taylor, B; Pimper, L E; Bedriñana-Romano, L; Rosenbaum, H C; Figueroa, C C

    2014-12-01

    Blue whales (Balaenoptera musculus) were among the most intensively exploited species of whales in the world. As a consequence of this intense exploitation, blue whale sightings off the coast of Chile were uncommon by the end of the 20th century. In 2004, a feeding and nursing ground was reported in southern Chile (SCh). With the aim to investigate the genetic identity and relationship of these Chilean blue whales to those in other Southern Hemisphere areas, 60 biopsy samples were collected from blue whales in SCh between 2003 and 2009. These samples were genotyped at seven microsatellite loci and the mitochondrial control region was sequenced, allowing us to identify 52 individuals. To investigate the genetic identity of this suspected remnant population, we compared these 52 individuals to blue whales from Antarctica (ANT, n = 96), Northern Chile (NCh, n = 19) and the eastern tropical Pacific (ETP, n = 31). No significant differentiation in haplotype frequencies (mtDNA) or among genotypes (nDNA) was found between SCh, NCh and ETP, while significant differences were found between those three areas and Antarctica for both the mitochondrial and microsatellite analyses. Our results suggest at least two breeding population units or subspecies exist, which is also supported by other lines of evidence such as morphometrics and acoustics. The lack of differences detected between SCh/NCh/ETP areas supports the hypothesis that eastern South Pacific blue whales are using the ETP area as a possible breeding area. Considering the small population sizes previously reported for the SCh area, additional conservation measures and monitoring of this population should be developed and prioritized.

  20. Source-Sink Estimates of Genetic Introgression Show Influence of Hatchery Strays on Wild Chum Salmon Populations in Prince William Sound, Alaska

    PubMed Central

    Jasper, James R.; Habicht, Christopher; Moffitt, Steve; Brenner, Rich; Marsh, Jennifer; Lewis, Bert; Creelman Fox, Elisabeth; Grauvogel, Zac; Rogers Olive, Serena D.; Grant, W. Stewart

    2013-01-01

    The extent to which stray, hatchery-reared salmon affect wild populations is much debated. Although experiments show that artificial breeding and culture influence the genetics of hatchery salmon, little is known about the interaction between hatchery and wild salmon in a natural setting. Here, we estimated historical and contemporary genetic population structures of chum salmon (Oncorhynchus keta) in Prince William Sound (PWS), Alaska, with 135 single nucleotide polymorphism (SNP) markers. Historical population structure was inferred from the analysis of DNA from fish scales, which had been archived since the late 1960’s for several populations in PWS. Parallel analyses with microsatellites and a test based on Hardy-Weinberg proportions showed that about 50% of the fish-scale DNA was cross-contaminated with DNA from other fish. These samples were removed from the analysis. We used a novel application of the classical source-sink model to compare SNP allele frequencies in these archived fish-scales (1964–1982) with frequencies in contemporary samples (2008–2010) and found a temporal shift toward hatchery allele frequencies in some wild populations. Other populations showed markedly less introgression, despite moderate amounts of hatchery straying. The extent of introgression may reflect similarities in spawning time and life-history traits between hatchery and wild fish, or the degree that hybrids return to a natal spawning area. The source-sink model is a powerful means of detecting low levels of introgression over several generations. PMID:24349150

  1. 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.

    PubMed

    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. PMID:26732752

  2. 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.

    PubMed

    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.

  3. A Genetic Monitoring and Evaluation Program for Supplemented Populations of Salmon and Steelhead in the Snake River Basin : 1992 Annual Report.

    SciTech Connect

    Waples, Robin S.

    1993-07-01

    This is the second report of research for an ongoing study to evaluate the genetic effects of using hatchery-reared fish to supplement natural populations of chinook salmon (Oncorhynchus tshawytscha) and steelhead (O. mykiss) in the Snake River Basin. The study plan involves yearly monitoring of genetic and meristic characteristics in hatchery, natural (supplemented), and wild (unsupplemented) populations in four different drainages for each species. This report summarizes the first two years of electrophoretic data for chinook salmon and steelhead and the first two years of meristic data for chinook salmon. Results obtained to date include the following: (1) Genetic variation was detected at 35 gene loci in chinook salmon and 50 gene loci in steelhead, both considerable increases over the number of polymorphic loci reported previously for Snake River populations. No substantial differences in levels of genetic variability were observed between years or between hatchery and natural/wild populations in either species. (2) In both species, statistically significant differences in allele frequency were typically found between years within populations. However, the temporal changes within populations were generally smaller than differences between populations. (3) Differences between chinook salmon populations classified as spring-and summer-run accounted for little of the overall genetic diversity; in contrast, substantial genetic differences were observed between ''B'' run steelhead from Dworshak Hatchery and ''A'' run populations from other study sites. (4) Estimates of the effective number of breeders per year (N,) derived from genetic data suggest that N{sub b} in natural and wild Snake River spring/summer chinook salmon populations is generally about one-quarter to three-quarters of the estimated number of adult spawners. (5) Analysis of the effects on data quality of sampling juveniles indicates that the small size of some wild fish may lead to a slight increase

  4. Salmon lice--impact on wild salmonids and salmon aquaculture.

    PubMed

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

    2013-03-01

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

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

    PubMed Central

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

    2013-01-01

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

  6. Evaluate Status of Pacific Lamprey in the Clearwater River and Salmon River Drainages, Idaho, 2009 Technical Report.

    SciTech Connect

    Cochnauer, Tim; Claire, Christopher

    2009-05-07

    Pacific lamprey Lampetra tridentata have received little attention in fishery science until recently, even though abundance has declined significantly along with other anadromous fish species in Idaho. Pacific lamprey in Idaho have to navigate over eight lower Snake River and Columbia River hydroelectric facilities for migration downstream as juveniles to the Pacific Ocean and again as adults migrating upstream to their freshwater spawning grounds in Idaho. The number of adult Pacific lamprey annually entering the Snake River basin at Ice Harbor Dam has declined from an average of over 18,000 during 1962-1969 to fewer than 600 during 1998-2006. Based on potential accessible streams and adult escapement over Lower Granite Dam on the lower Snake River, we estimate that no more than 200 Pacific lamprey adult spawners annually utilize the Clearwater River drainage in Idaho for spawning. We utilized electrofishing in 2000-2006 to capture, enumerate, and obtain biological information regarding rearing Pacific lamprey ammocoetes and macropthalmia to determine the distribution and status of the species in the Clearwater River drainage, Idaho. Present distribution in the Clearwater River drainage is limited to the lower sections of the Lochsa and Selway rivers, the Middle Fork Clearwater River, the mainstem Clearwater River, the South Fork Clearwater River, and the lower 7.5 km of the Red River. In 2006, younger age classes were absent from the Red River.

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

    SciTech Connect

    RH Visser

    2000-03-16

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

  8. Morphological differences in Pacific Coast populations of greater white-fronted geese

    USGS Publications Warehouse

    Orthmeyer, D.L.; Takekawa, J.Y.; Ely, C.R.; Wege, M.; Newton, W.E.

    1995-01-01

    We examined morphological relationships of three Pacific coast populations of Greater White-fronted Geese (Anser albifrons). Adult geese were captured and measured at three breeding areas in Alaska and two wintering areas in California, 1980-1991. A two-step discriminant function analysis examined morphological differences among the three populations. Stepwise discriminant function procedures created the simplest measurement models. Each sex was analyzed separately since multivariate analysis of variance indicated that males were significantly larger than females for all three populations. Tule Greater White-fronted Geese (A. a. gambelli) were significantly larger than Pacific Greater White-fronted Geese (A. a. frontalis), hereafter Pacific Geese. The first step of discriminant function analysis created models to differentiate Tule Geese from the Pacific Geese. Bivariate stepwise discriminant function models consisting of only two measurements correctly classified 92% of males (bill height, bill width) and 96% of females (bill height, culmen) of these subspecies. The second step of discriminant function analysis compared a small population of Pacific Geese from the Bristol Bay Lowlands (BBL) of southwestern Alaska with the large population of Pacific Geese that breed on the Yukon-Kuskokwim River Delta (YKD) of westcentral Alaska. We developed models with three (culmen, diagonal tarsus, midtoe) and five (culmen, diagonal tarsus, midtoe, total tarsus, bill height) measurements from stepwise discriminant function analyses to correctly classify 72% of males and 74% of females of these populations. Thus, morphology of Tule Geese differed highly significantly from Pacific Geese, as expected but differences between populations from the BBL and YKD areas were also significant. Morphometric analyses as these provided supporting evidence for clinal variation in populations of Greater White-fronted Geese. They also underscore a need for further studies of differences among

  9. Effects of stocking hatchery fish on the phenotype of indigenous populations in the amago salmon Oncorhynchus masou ishikawae in Japan.

    PubMed

    Kawamura, K; Furukawa, M; Kubota, M; Harada, Y

    2012-07-01

    The expression of colour marks (parr marks, red and black spots) of the amago salmon Oncorhynchus masou ishikawae was compared with microsatellite information, to see the effects of stocking hatchery fish on the phenotype of indigenous populations, which face extinction through extensive stocking. A Bayesian-based assignment test suggested introgression of two exotic clusters into one indigenous cluster in the stocked area and its vicinity. The number of parr marks was significantly higher in one hatchery-origin population, which exclusively comprised one exotic cluster. An increased number of red spots in stocked hatchery fish was probably a consequence of hatchery feeding conditions. The number of black spots was correlated with body size in many populations, except for hatchery and heavily introgressed populations. Coefficients of correlation and regression of black spots with body size, which were largest in indigenous populations, decreased with an increase of introgression by hatchery fish. As indigenous populations have low genetic diversity with high relatedness, it was inferred that the height of correlation and regression coefficients in black spots is caused by high genetic homogeneity and fixation of alleles in loci related to the increase of black spots, both of which might have collapsed with introgression by hatchery fish. These results suggest the possibility that introgression by stocked fish causes a change of phenotype in indigenous populations.

  10. Bull Trout Population Assessment in the White Salmon and Klickitat Rivers, Columbia River Gorge, Washington, 2001 Annual Report.

    SciTech Connect

    Thiesfeld, Steven L.; McPeak, Ronald H.; McNamara, Brian S.; Honanie, Isadore

    2002-01-01

    We utilized night snorkeling and single pass electroshocking to determine the presence or absence of bull trout Salvelinus confluentus in 26 stream reaches (3,415 m) in the White Salmon basin and in 71 stream reaches (9,005 m) in the Klickitat River basin during summer and fall 2001. We did not find any bull trout in the White Salmon River basin. In the Klickitat River basin, bull trout were found only in the West Fork Klickitat River drainage. We found bull trout in two streams not previously reported: Two Lakes Stream and an unnamed tributary to Fish Lake Stream (WRIA code number 30-0550). We attempted to capture downstream migrant bull trout in the West Fork Klickitat River by fishing a 1.5-m rotary screw trap at RM 4.3 from July 23 through October 17. Although we caught other salmonids, no bull trout were captured. The greatest limiting factor for bull trout in the West Fork Klickitat River is likely the small amount of available habitat resulting in a low total abundance, and the isolation of the population. Many of the streams are fragmented by natural falls, which are partial or complete barriers to upstream fish movement. To date, we have not been able to confirm that the occasional bull trout observed in the mainstem Klickitat River are migrating upstream into the West Fork Klickitat River.

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

    SciTech Connect

    Flagg, Thomas A.

    1996-03-01

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

  12. Evaluation of Salmon Spawning Below Bonneville Dam Annual Report October 2006 - September 2007.

    SciTech Connect

    Arntzen, Evan V.; Mueller, Robert P.; Murray, Katherine J.; Bott, Yi-Ju

    2008-08-08

    From 1999 through 2007, the Fish and Wildlife Program of the Bonneville Power Administration funded a project to determine the number of fall Chinook and chum salmon spawning downstream of Bonneville Dam, the characteristics of their spawning areas, and the flows necessary to ensure their long-term survival. Data were collected to ensure that established flow guidelines are appropriate and provide adequate protection for the species of concern. The projects objectives are consistent with the high priority placed by the Northwest Power and Conservation Council Independent Scientific Advisory Board and the salmon managers on determining the importance of mainstem habitats to the production of salmon in the Columbia River Basin. Because of the influence of mainstem habitat on salmon production, there is a continued need to better understand the physical habitat variables used by mainstem fall Chinook and chum salmon populations and the effects of hydropower project operations on spawning and incubation. During FY 2007, Pacific Northwest National Laboratory focused on (1) locating and mapping deep-water fall Chinook salmon and chum salmon spawning areas, (2) investigating the interaction between groundwater and surface water near fall Chinook and chum salmon spawning areas, and (3) providing in-season hyporheic temperature and water surface elevation data to assist state agencies with emergence timing and redd dewatering estimates. This report documents the studies and tasks performed by PNNL during FY 2007. Chapter 1 provides a description of the searches conducted for deepwater redds-adjacent to Pierce and Ives islands for fall Chinook salmon and near the Interstate 205 bridge for chum salmon. The chapter also provides data on redd location, information about habitat associations, and estimates of total spawning populations. Chapter 2 documents the collection of data on riverbed and river temperatures and water surface elevations, from the onset of spawning to the

  13. Understanding admixture patterns in supplemented populations: a case study combining molecular analyses and temporally explicit simulations in Atlantic salmon

    PubMed Central

    Perrier, Charles; Baglinière, Jean-Luc; Evanno, Guillaume

    2013-01-01

    Genetic admixture between wild and introduced populations is a rising concern for the management of endangered species. Here, we use a dual approach based on molecular analyses of samples collected before and after hatchery fish introduction in combination with a simulation study to obtain insight into the mechanisms of admixture in wild populations. Using 17 microsatellites, we genotyped pre- and post-stocking samples from four Atlantic salmon populations supplemented with non-native fish to estimate genetic admixture. We also used individual-based temporally explicit simulations based on realistic demographic and stocking data to predict the extent of admixture. We found a low admixture by hatchery stocks within prestocking samples but moderate to high values in post-stocking samples (from 12% to 60%). The simulation scenarios best fitting the real data suggested a 10–25 times lower survival of stocked fish relative to wild individuals. Simulations also suggested relatively high dispersal rates of stocked and wild fish, which may explain some high levels of admixture in weakly stocked populations and the persistence of indigenous genotypes in heavily stocked populations. This study overall demonstrates that combining genetic analyses with simulations can significantly improve the understanding of admixture mechanisms in wild populations. PMID:23798972

  14. Variation in freshwater growth and development among five New England Atlantic salmon (Salmo salar) populations reared in a common environment

    USGS Publications Warehouse

    Obedzinski, M.; Letcher, B.H.

    2004-01-01

    We examined phenotypic variation in growth and development from the eyed-egg stage to the age-1+ smolt stage among five New England populations of Atlantic salmon (Salmo salar: East Machias, Narraguagus, Sheepscot, Penobscot, Connecticut) reared in a common laboratory environment. Study populations originated from rivers varying in size, latitude, and level of hatchery supplementation and included one reintroduced population (Connecticut was a recipient of Penobscot origin stock). Phenotypic trait differences were found among populations, and the degree of stock variation depended on ontogeny. Eggs were smaller and hatched sooner in the Penobscot (a northern, intensively managed population), but no stock differences were detected in size or growth efficiency from the onset of exogenous feeding to age 0+ summer. Differences again emerged in age 0+ autumn, with the degree of bimodality in length-frequency distributions differing among stocks; the Connecticut had the highest proportion of upper-mode fish and, ultimately, age-1+ smolts. Although genetic effects could not be entirely separated from maternal effects for egg size variation, it is likely that differences in hatch timing and smolt age had a genetic basis. Early emphasis on age-1+ hatchery-reared smolts in the Connecticut may have led to divergence in smolt age between the Penobscot and Connecticut populations in less than eight generations. ?? 2004 NRC Canada.

  15. Application of AN Empirically Scaled Digital Echo Integrator for Assessment of Juvenile Sockeye Salmon (oncorhynchus Nerka Walbaum) Populations.

    NASA Astrophysics Data System (ADS)

    Nunnallee, Edmund Pierce, Jr.

    1980-03-01

    This dissertation consists of an investigation into the empirical scaling of a digital echo integrator for assessment of a population of juvenile sockeye salmon in Cultus Lake, British Columbia, Canada. The scaling technique was developed over the last ten years for use with totally uncalibrated but stabilized data collection and analysis equipment, and has been applied to populations of fish over a wide geographical range. This is the first investigation into the sources of bias and the accuracy of the technique, however, and constitutes a verification of the method. The initial section of the investigation describes hydroacoustic data analysis methods for estimation of effective sampling volume which is necessary for estimation of fish density. The second section consists of a computer simulation of effective sample volume estimation by this empirical method and is used to investigate the degree of bias introduced by electronic and physical parameters such as boat speed -fish depth interaction effects, electronic thresholding and saturation, transducer beam angle, fish depth stratification by size and spread of the target strength distribution of the fish. Comparisons of simulation predictions of sample volume estimation bias to actual survey results are given at the end of this section. A verification of the scaling method is then presented by comparison of a hydroacoustically derived estimation of the Cultus Lake smolt population to an independent and concurrent estimate made by counting the migrant fish as they passed through a weir in the outlet stream of the lake. Finally, the effect on conduct and accuracy of hydroacoustic assessment of juvenile sockeye salmon due to several behavioral traits are discussed. These traits include movements of presmolt fish in a lake just prior to their outmigration, daily vertical migrations and the emergence and dispersal of sockeye fry in Cultus Lake. In addition, a comparison of the summer depth preferences of the fish

  16. Genetic isolation between the Western and Eastern Pacific populations of pronghorn spiny lobster Panulirus penicillatus.

    PubMed

    Chow, Seinen; Jeffs, Andrew; Miyake, Yoichi; Konishi, Kooichi; Okazaki, Makoto; Suzuki, Nobuaki; Abdullah, Muhamad F; Imai, Hideyuki; Wakabayasi, Toshie; Sakai, Mitsuo

    2011-01-01

    The pronghorn spiny lobster, Panulirus penicillatus, is a circumtropical species which has the widest global distribution among all the species of spiny lobster, ranging throughout the entire Indo-Pacific region. Partial nucleotide sequences of mitochondrial DNA COI (1,142-1,207 bp) and 16S rDNA (535-546 bp) regions were determined for adult and phyllosoma larval samples collected from the Eastern Pacific (EP)(Galápagos Islands and its adjacent water), Central Pacific (CP)(Hawaii and Tuamotu) and the Western Pacific (WP)(Japan, Indonesia, Fiji, New Caledonia and Australia). Phylogenetic analyses revealed two distinct large clades corresponding to the geographic origin of samples (EP and CP+WP). No haplotype was shared between the two regional samples, and average nucleotide sequence divergence (Kimura's two parameter distance) between EP and CP+WP samples was 3.8±0.5% for COI and 1.0±0.4% for 16S rDNA, both of which were much larger than those within samples. The present results indicate that the Pacific population of the pronghorn spiny lobster is subdivided into two distinct populations (Eastern Pacific and Central to Western Pacific), with no gene flow between them. Although the pronghorn spiny lobster have long-lived teleplanic larvae, the vast expanse of Pacific Ocean with no islands and no shallow substrate which is known as the East Pacific Barrier appears to have isolated these two populations for a long time (c.a. 1MY). PMID:22195038

  17. Genetic Isolation between the Western and Eastern Pacific Populations of Pronghorn Spiny Lobster Panulirus penicillatus

    PubMed Central

    Chow, Seinen; Jeffs, Andrew; Miyake, Yoichi; Konishi, Kooichi; Okazaki, Makoto; Suzuki, Nobuaki; Abdullah, Muhamad F.; Imai, Hideyuki; Wakabayasi, Toshie; Sakai, Mitsuo

    2011-01-01

    The pronghorn spiny lobster, Panulirus penicillatus, is a circumtropical species which has the widest global distribution among all the species of spiny lobster, ranging throughout the entire Indo-Pacific region. Partial nucleotide sequences of mitochondrial DNA COI (1,142–1,207 bp) and 16S rDNA (535–546 bp) regions were determined for adult and phyllosoma larval samples collected from the Eastern Pacific (EP)(Galápagos Islands and its adjacent water), Central Pacific (CP)(Hawaii and Tuamotu) and the Western Pacific (WP)(Japan, Indonesia, Fiji, New Caledonia and Australia). Phylogenetic analyses revealed two distinct large clades corresponding to the geographic origin of samples (EP and CP+WP). No haplotype was shared between the two regional samples, and average nucleotide sequence divergence (Kimura's two parameter distance) between EP and CP+WP samples was 3.8±0.5% for COI and 1.0±0.4% for 16S rDNA, both of which were much larger than those within samples. The present results indicate that the Pacific population of the pronghorn spiny lobster is subdivided into two distinct populations (Eastern Pacific and Central to Western Pacific), with no gene flow between them. Although the pronghorn spiny lobster have long-lived teleplanic larvae, the vast expanse of Pacific Ocean with no islands and no shallow substrate which is known as the East Pacific Barrier appears to have isolated these two populations for a long time (c.a. 1MY). PMID:22195038

  18. Re-Creating Missing Population Baselines for Pacific Reef Sharks

    PubMed Central

    Nadon, Marc O; Baum, Julia K; Williams, Ivor D; Mcpherson, Jana M; Zgliczynski, Brian J; Richards, Benjamin L; Schroeder, Robert E; Brainard, Russell E

    2012-01-01

    Summary Abstract Sharks and other large predators are scarce on most coral reefs, but studies of their historical ecology provide qualitative evidence that predators were once numerous in these ecosystems. Quantifying density of sharks in the absence of humans (baseline) is, however, hindered by a paucity of pertinent time-series data. Recently researchers have used underwater visual surveys, primarily of limited spatial extent or nonstandard design, to infer negative associations between reef shark abundance and human populations. We analyzed data from 1607 towed-diver surveys (>1 ha transects surveyed by observers towed behind a boat) conducted at 46 reefs in the central-western Pacific Ocean, reefs that included some of the world's most pristine coral reefs. Estimates of shark density from towed-diver surveys were substantially lower (<10%) than published estimates from surveys along small transects (<0.02 ha), which is not consistent with inverted biomass pyramids (predator biomass greater than prey biomass) reported by other researchers for pristine reefs. We examined the relation between the density of reef sharks observed in towed-diver surveys and human population in models that accounted for the influence of oceanic primary productivity, sea surface temperature, reef area, and reef physical complexity. We used these models to estimate the density of sharks in the absence of humans. Densities of gray reef sharks (Carcharhinus amblyrhynchos), whitetip reef sharks (Triaenodon obesus), and the group “all reef sharks” increased substantially as human population decreased and as primary productivity and minimum sea surface temperature (or reef area, which was highly correlated with temperature) increased. Simulated baseline densities of reef sharks under the absence of humans were 1.1–2.4/ha for the main Hawaiian Islands, 1.2–2.4/ha for inhabited islands of American Samoa, and 0.9–2.1/ha for inhabited islands in the Mariana Archipelago, which suggests

  19. Re-Creating Missing Population Baselines for Pacific Reef Sharks

    PubMed Central

    Nadon, Marc O; Baum, Julia K; Williams, Ivor D; Mcpherson, Jana M; Zgliczynski, Brian J; Richards, Benjamin L; Schroeder, Robert E; Brainard, Russell E

    2012-01-01

    Summary Abstract Sharks and other large predators are scarce on most coral reefs, but studies of their historical ecology provide qualitative evidence that predators were once numerous in these ecosystems. Quantifying density of sharks in the absence of humans (baseline) is, however, hindered by a paucity of pertinent time-series data. Recently researchers have used underwater visual surveys, primarily of limited spatial extent or nonstandard design, to infer negative associations between reef shark abundance and human populations. We analyzed data from 1607 towed-diver surveys (>1 ha transects surveyed by observers towed behind a boat) conducted at 46 reefs in the central-western Pacific Ocean, reefs that included some of the world's most pristine coral reefs. Estimates of shark density from towed-diver surveys were substantially lower (<10%) than published estimates from surveys along small transects (<0.02 ha), which is not consistent with inverted biomass pyramids (predator biomass greater than prey biomass) reported by other researchers for pristine reefs. We examined the relation between the density of reef sharks observed in towed-diver surveys and human population in models that accounted for the influence of oceanic primary productivity, sea surface temperature, reef area, and reef physical complexity. We used these models to estimate the density of sharks in the absence of humans. Densities of gray reef sharks (Carcharhinus amblyrhynchos), whitetip reef sharks (Triaenodon obesus), and the group “all reef sharks” increased substantially as human population decreased and as primary productivity and minimum sea surface temperature (or reef area, which was highly correlated with temperature) increased. Simulated baseline densities of reef sharks under the absence of humans were 1.1–2.4/ha for the main Hawaiian Islands, 1.2–2.4/ha for inhabited islands of American Samoa, and 0.9–2.1/ha for inhabited islands in the Mariana Archipelago, which suggests

  20. Population and employment in selected countries bordering the Pacific.

    PubMed

    Concepcion, M B

    1982-12-01

    This study is concerned with the dynamics of labor force composition in selected countries bordering the Pacific. The estimates presented are based on national definitions of urban and rural places and of the labor force and are derived primarily from published U.N. data. Variations in labor force composition and in urbanization levels by country are discussed. Countries considered include Canada, Costa Rica, Ecuador, Japan, the Republic of Korea, Nicaragua, Peru, the Philippines, and the United States.

  1. Asymmetric hybridization and introgression between pink salmon and chinook salmon in the Laurentian Great Lakes

    USGS Publications Warehouse

    Rosenfield, Jonathan A.; Todd, Thomas; Greil, Roger

    2000-01-01

    Among Pacific salmon collected in the St. Marys River, five natural hybrids of pink salmon Oncorhynchus gorbuscha and chinook salmon Oncorhynchus tshawytscha and one suspected backcross have been detected using morphologic, meristic, and color evidence. One allozyme (LDH, l-lactate dehydrogenase from muscle) and one nuclear DNA locus (growth hormone) for which species-specific fixed differences exist were analyzed to detect additional hybrids and to determine if introgression had occurred. Restriction fragment length polymorphism of mitochondrial DNA (mtDNA) was used to identify the maternal parent of each hybrid. Evidence of introgression was found among the five previously identified hybrids. All hybrid specimens had chinook salmon mtDNA, indicating that hybridization between chinook salmon and pink salmon in the St. Marys River is asymmetric and perhaps unidirectional. Ecological, physiological, and sexual selection forces may contribute to this asymmetric hybridization. Introgression between these highly differentiated species has implications for management, systematics, and conservation of Pacific salmon.

  2. Long-term effects of translocation and release numbers on fine-scale population structure among coho salmon (Oncorhynchus kisutch).

    PubMed

    Eldridge, William H; Naish, Kerry A

    2007-06-01

    Management actions, such as translocations, reintroductions and supportive breeding, can have both negative and positive effects on population recovery. Several studies have examined the incidence of introgression following such actions, but few studies have explored the effect of release numbers on gene flow between closely related recipient populations. We examined population structure of coho salmon in Puget Sound (Washington State, USA) to evaluate the relationship between the number of individuals transferred between rivers, and the number released within rivers, on inter- and intrariver population divergence. Eleven microsatellite loci were surveyed in 23 hatchery and wild samples collected from 11 rivers within and one hatchery outside Puget Sound. Pairwise genetic divergences between most populations were significant, but the population structure could not be explained by an isolation-by-distance model (Mantel test, P > 0.05). In contrast, we detected significant hatchery influence on population structure. The numbers of fish transferred among rivers between 1952 and 2004 was negatively correlated with differentiation between rivers (partial Mantel test, P = 0.005) but not within rivers (t-test, P = 0.41). Number of fish released from hatcheries that collect broodstock locally was negatively correlated with population structure within rivers (t-test P = 0.002), and between nearby rivers (partial Mantel P = 0.04). Our results indicate that the population structure can, to some degree, be altered by the number of individuals transferred and by local release number of individuals in ongoing artificial propagation programs. The findings presented here emphasize the need to control the number of individuals that are either inadvertently introduced, or are deliberately released under conservation scenarios.

  3. Mortality of seabirds in high-seas salmon gillnets

    USGS Publications Warehouse

    Ainley, D.G.; DeGange, A.R.; Jones, L.L.; Beach, R.J.

    1981-01-01

    Since 1952, the Japanese have operated a large salmon driftnet.fishery in the northern North Pacific Ocean and Bering Sea. This fishery is divided into two components: the high-seas mothership fleet, which consists of several processing ships and their numerous, smaller catcher boats that remain at sea during the entire fishing season, and the land-based fleet, which consists of independent fishing boats that catch and store their own fish and return to Japan at more frequent intervals (Sanger 1976; Fredin et al. 2 ). A similar fishery in the North Atlantic between 1965 and 1976 was responsible for the deaths of large numbers of the thick-billed murre, Uria lomvia, and significant reductions in its breeding populations (Tull et al. 1972). Recent work in the North Pacific and Bering Sea by Sana (1978) and King et al. (1979) indicated that large numbers of seabirds are killed annually in the Japanese salmon fishery also.

  4. Fisheries productivity in the northeastern Pacific Ocean over the past 2,200 years

    NASA Astrophysics Data System (ADS)

    Finney, Bruce P.; Gregory-Eaves, Irene; Douglas, Marianne S. V.; Smol, John P.

    2002-04-01

    Historical catch records suggest that climatic variability has had basin-wide effects on the northern Pacific and its fish populations, such as salmon, sardines and anchovies. However, these records are too short to define the nature and frequency of patterns. We reconstructed ~2,200-year records of sockeye salmon abundance from sediment cores obtained from salmon nursery lakes on Kodiak island, Alaska. Large shifts in abundance, which far exceed the decadal-scale variability recorded during the past 300 years, occurred over the past two millennia. A marked, multi-centennial decline in Alaskan sockeye salmon was apparent from ~100BC to AD 800, but salmon were consistently more abundant from AD1200 to 1900. Over the past two millennia, the abundances of Pacific sardine and Northern anchovy off the California coast, and of Alaskan salmon, show several synchronous patterns of variability. But sardines and anchovies vary out of phase with Alaskan salmon over low frequency, which differs from the pattern detected in historical records. The coherent patterns observed across large regions demonstrate the strong role of climatic forcing in regulating northeastern Pacific fish stocks.

  5. Salmon Patch

    MedlinePlus

    ... the head. Salmon patches are different from port-wine stains (discussed as a separate topic) in that ... difference between a salmon patch and a port-wine stain. In the past, port-wine stains and ...

  6. Chronic exposure to polynuclear aromatic hydrocarbons in natal habitats leads to decreased equilibrium size, growth, and stability of pink salmon populations.

    PubMed

    Heintz, Ron A

    2007-07-01

    The immediate and delayed effects of embryonic exposure to low levels of polynuclear aromatic hydrocarbons (PAHs) have been shown to reduce survival to maturity by 50% in exposed pink salmon populations. This suggests that chronically exposed populations could be extirpated over relatively few generations, but the effect of density dependence on extirpation rate is unknown. This study examines the interaction of PAH effects and randomly varying density dependence on a simulated population. The simulation derives from 70 years of observations made on a single pink salmon population and toxicity studies involving a hatchery population in the same watershed. Results from simulations involving exposure of 100% of the population to effects consistent with an aqueous PAH concentration of 18 nL/L indicate an 80% decrease in population productivity and an 11% probability of extinction after 35 generations. In contrast, population growth rate declined by only 5%. Further decreases in survival relative to that of observed PAH effects rapidly increase the probability of extinction. Data from these simulations demonstrate that, at low levels of exposure, density dependence can compensate for reduced population size and buffer the population against extinction. However, if equilibrium size is depressed sufficiently, random environmental variation overcomes the buffering effect of density dependence and extinction probability increases. These data demonstrate that extinction probability and population size are more sensitive measures of population effects than growth rate for wild populations regulated by density dependence.

  7. Dental caries in South Pacific populations: a review.

    PubMed

    Cutress, T W

    2003-03-01

    Dental caries (tooth decay) was uncommon in Pacific Island communities before European trading and migration expanded into the Region. The etiology of this oral microbial disease is a consequence of changed diets, food preparation and lifestyle. In particular, the easy availability of a high level of frequent dietary supplementation with refined sucrose (sugar) and carbohydrates is the key factor in the etiology of tooth decay. While tooth decay initially developed as a health problem in the more accessible Pacific islands over a century ago, it has spread increasingly as trading, travel and cash economies have developed to include even the more geographically remote communities. In this review selected epidemiological data are presented to show the magnitude, variation and secular changes in the prevalence of tooth decay in different communities. Tooth decay in conjunction with the historically endemic adult gum diseases poses a major public health problem in terms of pain, premature loss of teeth and the need for oral rehabilitation. Implementation and monitoring of caries control programs is a priority need in most communities. It is impractical to consider a return to indigenous diets and lifestyles as a strategy for caries prevention. Instead promotion of proven modern community preventive programmes, notably appropriate use of fluorides, 'fissure sealants' together with control of excessive consumption of diets rich in refined sugar is required if a significant increase in the levels of tooth decay is to be avoided.

  8. Dental caries in South Pacific populations: a review.

    PubMed

    Cutress, T W

    2003-03-01

    Dental caries (tooth decay) was uncommon in Pacific Island communities before European trading and migration expanded into the Region. The etiology of this oral microbial disease is a consequence of changed diets, food preparation and lifestyle. In particular, the easy availability of a high level of frequent dietary supplementation with refined sucrose (sugar) and carbohydrates is the key factor in the etiology of tooth decay. While tooth decay initially developed as a health problem in the more accessible Pacific islands over a century ago, it has spread increasingly as trading, travel and cash economies have developed to include even the more geographically remote communities. In this review selected epidemiological data are presented to show the magnitude, variation and secular changes in the prevalence of tooth decay in different communities. Tooth decay in conjunction with the historically endemic adult gum diseases poses a major public health problem in terms of pain, premature loss of teeth and the need for oral rehabilitation. Implementation and monitoring of caries control programs is a priority need in most communities. It is impractical to consider a return to indigenous diets and lifestyles as a strategy for caries prevention. Instead promotion of proven modern community preventive programmes, notably appropriate use of fluorides, 'fissure sealants' together with control of excessive consumption of diets rich in refined sugar is required if a significant increase in the levels of tooth decay is to be avoided. PMID:16276946

  9. Survey of pathogens in hatchery Chinook salmon with different out-migration histories through the Snake and Columbia rivers.

    PubMed

    Van Gaest, A L; Dietrich, J P; Thompson, D E; Boylen, D A; Strickland, S A; Collier, T K; Loge, F J; Arkoosh, M R

    2011-06-01

    The operation of the Federal Columbia River Power System (FCRPS) has negatively affected threatened and endangered salmonid populations in the Pacific Northwest. Barging Snake River spring Chinook salmon Oncorhynchus tshawytscha through the FCRPS is one effort to mitigate the effect of the hydrosystem on juvenile salmon out-migration. However, little is known about the occurrence and transmission of infectious agents in barged juvenile salmon relative to juvenile salmon that remain in-river to navigate to the ocean. We conducted a survey of hatchery-reared spring Chinook salmon at various points along their out-migration path as they left their natal hatcheries and either migrated in-river or were barged through the FCRPS. Salmon kidneys were screened by polymerase chain reaction for nine pathogens and one family of water molds. Eight pathogens were detected; the most prevalent were Renibacterium salmoninarum and infectious hematopoietic necrosis virus. Species in the family Saprolegniaceae were also commonly detected. Pathogen prevalence was significantly greater in fish that were barged through the FCRPS than in fish left to out-migrate in-river. These results suggest that the transmission of infectious agents to susceptible juvenile salmon occurs during the barging process. Therefore, management activities that reduce pathogen exposure during barging may increase the survival of juvenile Chinook salmon after they are released.

  10. Signatures of resistance to Lepeophtheirus salmonis include a TH2-type response at the louse-salmon interface.

    PubMed

    Braden, Laura M; Koop, Ben F; Jones, Simon R M

    2015-01-01

    Disease outbreaks with the salmon louse Lepeophtheirus salmonis cause significant economic losses in mariculture operations worldwide. Variable innate immune responses at the louse-attachment site contribute to differences in susceptibility among species such that members of Salmo spp. are more susceptible to infection than those of some Oncorhynchus spp. Relatively little is known about the mechanisms that contribute to disease resistance or susceptibility to L. salmonis in salmon. Here, we utilize histochemistry and transcriptomics in a comparative infection model with susceptible (Atlantic, sockeye) and resistant (coho) salmon. At least three cell populations (MHIIβ+, IL1β+, TNFα+) were activated in coho salmon skin during L. salmonis infection. Locally elevated expression of several pro-inflammatory mediators (e.g. IL1β, IL8, TNFα, COX2, C/EBPβ), and tissue repair enzymes (MMP9, MMP13) were detected in susceptible and resistant species. However, responses specific to coho salmon (e.g. IL4, IL6, TGFβ) or responses shared among susceptible salmon (e.g. SAP, TRF, Cath in Atlantic and sockeye salmon) provide evidence for species-specific pathways contributing to resistance or susceptibility, respectively. Our results confirm the importance of an early pro-inflammatory TH1-type pathway as an initial host response during infection with Pacific sea lice, and demonstrate subsequent regulatory TH2-type processes as candidate defense mechanisms in the skin of resistant coho salmon. PMID:25453579

  11. SALMON RECOVERY: DEFENDING REALITY, DELUSIONS, AND OTHER ASSORTED TRUTHS

    EPA Science Inventory

    Are professional fisheries scientists collectively guilty of encouraging delusions about the possibilities for restoring wild salmon to the Pacific Northwest? Do they perpetuate the fantasy that the Pacific Northwest will (or could, absent pervasive life-style changes) support w...

  12. Population genetic structure of annual and perennial populations of Zostera marina L. along the Pacific coast of Baja California and the Gulf of California

    USGS Publications Warehouse

    Munoz-Salazar, R.; Talbot, S.L.; Sage, G.K.; Ward, D.H.; Cabello-Pasini, Alejandro

    2005-01-01

    The Baja California peninsula represents a biogeographical boundary contributing to regional differentiation among populations of marine animals. We investigated the genetic characteristics of perennial and annual populations of the marine angiosperm, Zostera marina, along the Pacific coast of Baja California and in the Gulf of California, respectively. Populations of Z. marina from five coastal lagoons along the Pacific coast and four sites in the Gulf of California were studied using nine microsatellite loci. Analyses of variance revealed significant interregional differentiation, but no subregional differentiation. Significant spatial differentiation, assessed using θ values, was observed among all populations within the two regions. Z. marina populations along the Pacific coast are separated by more than 220 km and had the greatest θ (0.13-0.28) values, suggesting restricted gene flow. In contrast, lower but still significant genetic differentiation was observed among populations within the Gulf of California (θ = 0.04-0.18), even though populations are separated by more than 250 km. This suggests higher levels of gene flow among Gulf of California populations relative to Pacific coast populations. Direction of gene flow was predominantly southward among Pacific coast populations, whereas no dominant polarity in the Gulf of California populations was observed. The test for isolation by distance (IBD) showed a significant correlation between genetic and geographical distances in Gulf of California populations, but not in Pacific coast populations, perhaps because of shifts in currents during El Nino Southern Oscillation (ENSO) events along the Pacific coast.

  13. Population genetic structure of annual and perennial populations of Zostera marina L. along the Pacific coast of Baja California and the Gulf of California.

    PubMed

    Muñiz-Salazar, Raquel; Talbot, Sandra L; Sage, George K; Ward, David H; Cabello-Pasini, Alejandro

    2005-03-01

    The Baja California peninsula represents a biogeographical boundary contributing to regional differentiation among populations of marine animals. We investigated the genetic characteristics of perennial and annual populations of the marine angiosperm, Zostera marina, along the Pacific coast of Baja California and in the Gulf of California, respectively. Populations of Z. marina from five coastal lagoons along the Pacific coast and four sites in the Gulf of California were studied using nine microsatellite loci. Analyses of variance revealed significant interregional differentiation, but no subregional differentiation. Significant spatial differentiation, assessed using theta(ST) values, was observed among all populations within the two regions. Z. marina populations along the Pacific coast are separated by more than 220 km and had the greatest theta(ST) (0.13-0.28) values, suggesting restricted gene flow. In contrast, lower but still significant genetic differentiation was observed among populations within the Gulf of California (theta(ST) = 0.04-0.18), even though populations are separated by more than 250 km. This suggests higher levels of gene flow among Gulf of California populations relative to Pacific coast populations. Direction of gene flow was predominantly southward among Pacific coast populations, whereas no dominant polarity in the Gulf of California populations was observed. The test for isolation by distance (IBD) showed a significant correlation between genetic and geographical distances in Gulf of California populations, but not in Pacific coast populations, perhaps because of shifts in currents during El Niño Southern Oscillation (ENSO) events along the Pacific coast.

  14. Controls on the entrainment of juvenile Chinook Salmon (Oncorhynchus tshawytscha) into large water diversions and estimates of population-level loss.

    PubMed

    Zeug, Steven C; Cavallo, Bradley J

    2014-01-01

    Diversion of freshwater can cause significant changes in hydrologic dynamics and this can have negative consequences for fish populations. Additionally, fishes can be directly entrained into diversion infrastructure (e.g. canals, reservoirs, pumps) where they may become lost to the population. However, the effect of diversion losses on fish population dynamics remains unclear. We used 15 years of release and recovery data from coded-wire-tagged juvenile Chinook Salmon (Oncorhynchus tshawytscha) to model the physical, hydrological and biological predictors of salvage at two large water diversions in the San Francisco Estuary. Additionally, entrainment rates were combined with estimates of mortality during migration to quantify the proportion of total mortality that could be attributed to diversions. Statistical modeling revealed a strong positive relationship between diversion rate and fish entrainment at both diversions and all release locations. Other significant relationships were specific to the rivers where the fish were released, and the specific diversion facility. Although significant relationships were identified in statistical models, entrainment loss and the mean contribution of entrainment to total migration mortality were low. The greatest entrainment mortality occurred for fish released along routes that passed closest to the diversions and certain runs of Chinook Salmon released in the Sacramento River suffered greater mortality but only at the highest diversion rates observed during the study. These results suggest losses at diversions should be put into a population context in order to best inform effective management of Chinook Salmon populations. PMID:25019205

  15. Controls on the Entrainment of Juvenile Chinook Salmon (Oncorhynchus tshawytscha) into Large Water Diversions and Estimates of Population-Level Loss

    PubMed Central

    Zeug, Steven C.; Cavallo, Bradley J.

    2014-01-01

    Diversion of freshwater can cause significant changes in hydrologic dynamics and this can have negative consequences for fish populations. Additionally, fishes can be directly entrained into diversion infrastructure (e.g. canals, reservoirs, pumps) where they may become lost to the population. However, the effect of diversion losses on fish population dynamics remains unclear. We used 15 years of release and recovery data from coded-wire-tagged juvenile Chinook Salmon (Oncorhynchus tshawytscha) to model the physical, hydrological and biological predictors of salvage at two large water diversions in the San Francisco Estuary. Additionally, entrainment rates were combined with estimates of mortality during migration to quantify the proportion of total mortality that could be attributed to diversions. Statistical modeling revealed a strong positive relationship between diversion rate and fish entrainment at both diversions and all release locations. Other significant relationships were specific to the rivers where the fish were released, and the specific diversion facility. Although significant relationships were identified in statistical models, entrainment loss and the mean contribution of entrainment to total migration mortality were low. The greatest entrainment mortality occurred for fish released along routes that passed closest to the diversions and certain runs of Chinook Salmon released in the Sacramento River suffered greater mortality but only at the highest diversion rates observed during the study. These results suggest losses at diversions should be put into a population context in order to best inform effective management of Chinook Salmon populations. PMID:25019205

  16. 150 YEARS OF SALMON RESTORATION: ASSORTED TRUTHS

    EPA Science Inventory

    Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline of wild Pacific salmon. Of the Earth's four regions (i.e., Asian Far East, Atlantic Europe, eastern North America, and western North America) where salmon runs originally occurred, it...

  17. SALMON RECOVERY: LEARNING FROM SUCCESSES AND FAILURES

    EPA Science Inventory

    Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline of wild Pacific salmon. Of the Earth's four regions (i.e., Asian Far East, Atlantic Europe, eastern North America, and western North America) where salmon runs occurred originally, it...

  18. SALMON RECOVERY: LEARNING FROM SUCCESSES AND MISTAKES

    EPA Science Inventory

    Billions of dollars have been spent in a so-far failed attempt to reverse the long-term decline of wild Pacific salmon. Of the Earth's four regions (i.e., Asian Far East, Atlantic Europe, eastern North America, and western North America) where salmon runs occurred originally, it...

  19. Three Decades of Farmed Escapees in the Wild: A Spatio-Temporal Analysis of Atlantic Salmon Population Genetic Structure throughout Norway

    PubMed Central

    Glover, Kevin A.; Quintela, María; Wennevik, Vidar; Besnier, François; Sørvik, Anne G. E.; Skaala, Øystein

    2012-01-01

    Each year, hundreds of thousands of domesticated farmed Atlantic salmon escape into the wild. In Norway, which is the world’s largest commercial producer, many native Atlantic salmon populations have experienced large numbers of escapees on the spawning grounds for the past 15–30 years. In order to study the potential genetic impact, we conducted a spatio-temporal analysis of 3049 fish from 21 populations throughout Norway, sampled in the period 1970–2010. Based upon the analysis of 22 microsatellites, individual admixture, FST and increased allelic richness revealed temporal genetic changes in six of the populations. These changes were highly significant in four of them. For example, 76% and 100% of the fish comprising the contemporary samples for the rivers Vosso and Opo were excluded from their respective historical samples at P = 0.001. Based upon several genetic parameters, including simulations, genetic drift was excluded as the primary cause of the observed genetic changes. In the remaining 15 populations, some of which had also been exposed to high numbers of escapees, clear genetic changes were not detected. Significant population genetic structuring was observed among the 21 populations in the historical (global FST = 0.038) and contemporary data sets (global FST = 0.030), although significantly reduced with time (P = 0.008). This reduction was especially distinct when looking at the six populations displaying temporal changes (global FST dropped from 0.058 to 0.039, P = 0.006). We draw two main conclusions: 1. The majority of the historical population genetic structure throughout Norway still appears to be retained, suggesting a low to modest overall success of farmed escapees in the wild; 2. Genetic introgression of farmed escapees in native salmon populations has been strongly population-dependent, and it appears to be linked with the density of the native population. PMID:22916215

  20. PNW WILD SALMON IN 2100: AN ALTERNATIVE FUTURES PERSPECTIVE ON SALMON RECOVERY

    EPA Science Inventory

    The primary goal of the Salmon 2100 Project is to identify practical options that have a high probability of maintaining biologically significant, sustainable populations of wild salmon in California, Oregon, Washington, Idaho, and southern British Columbia. The Project does not...

  1. WILD SALMON IN 2100: AN ALTERNATIVE FUTURES PERSPECTIVE ON SALMON RECOVERY - MAY 2006

    EPA Science Inventory

    The primary goal of the Salmon 2100 Project is to identify practical options that have a high probability of maintaining biologically significant, sustainable populations of wild salmon in California, Oregon, Washington, Idaho, and southern British Columbia. The Project does not...

  2. SALMON 2100 PROJECT: LIKELY SCENARIOS FOR WILD SALMON

    EPA Science Inventory

    The primary goal of the Salmon 2100 Project is to identify practical options that have a high probability of maintaining biologically significant, sustainable populations of wild salmon in California, Oregon, Washington, Idaho, and British Columbia. The Project does not support o...

  3. Genetic Variation in DNA of Coho Salmon from the Lower Columbia River : Final Report 1993.

    SciTech Connect

    Fobes, Stephen; Knudsen, Kathy; Allendorf, Fred

    1993-04-01

    The goal of this project was to develop techniques to provide the information needed to determine if Lower Columbia River coho salmon represent a 'species' under the Endangered Species Act. Our report features two new nuclear DNA approaches to the improved detection of genetic variation: (1) Studies of DNA-level genetic variation for two nuclear growth hormone genes; (2) Use of arbitrary DNA primers (randomly amplified polymorphic DNA, or 'RAPD' primers) to detect variation at large numbers of nuclear genes. We used the polymerase chain reaction (PCR) to amplify variable sections (introns) of two growth hormone genes (GH-I and G/f-Z) in several salmonid species. Coho salmon had three DNA length variants for G/-I intron C. Restriction analysis and sequencing provided valuable information about the mode of evolution of these DNA sequences. We tested segregation of the variants in captive broods of coho salmon, and demonstrated that they are alleles at a single Mendelian locus. Population studies using the GH-1 alleles showed highly significant frequency differences between Lower Columbia River and Oregon Coast coho salmon, and marginal differences among stocks within these regions. These new markers are adequately defined and tested to use in coho salmon population studies of any size. The nature of the variation at GH-1 (Variable Number Tandem Repeats, or 'VNTRs') suggests that more genetic variants will be found in coho salmon from other areas. GH-2 intron C also showed length variation in coho salmon, and this variation was found to be sex-linked. Because PCR methods require minute amounts of tissue, this discovery provides a technique to determine the gender of immature coho salmon without killing them. Chinook salmon had restriction patterns and sequence divergences similar to coho salmon. Thus, we expect that sex linkage of GH-2 alleles predates the evolutionary divergence of Pacific salmon species, and that gender testing with this system will work on the

  4. The MHC and non-random mating in a captive population of Chinook salmon.

    PubMed

    Neff, B D; Garner, S R; Heath, J W; Heath, D D

    2008-08-01

    Detailed analysis of variation in reproductive success can provide an understanding of the selective pressures that drive the evolution of adaptations. Here, we use experimental spawning channels to assess phenotypic and genotypic correlates of reproductive success in Chinook salmon (Oncorhynchus tshawytscha). Groups of 36 fish in three different sex ratios (1:2, 1:1 and 2:1) were allowed to spawn and the offspring were collected after emergence from the gravel. Microsatellite genetic markers were used to assign parentage of each offspring, and the parents were also typed at the major histocompatibility class IIB locus (MHC). We found that large males, and males with brighter coloration and a more green/blue hue on their lateral integument sired more offspring, albeit only body size and brightness had independent effects. There was no similar relationship between these variables and female reproductive success. Furthermore, there was no effect of sex ratio on the strength or significance of any of the correlations. Females mated non-randomly at the MHC, appearing to select mates that produced offspring with greater genetic diversity as measured by amino-acid divergence. Females mated randomly with respect to male genetic relatedness and males mated randomly with respect to both MHC and genetic relatedness. These results indicate that sexual selection favours increased body size and perhaps integument coloration in males as well as increases genetic diversity at the MHC by female mate choice.

  5. Genetic variation in bacterial kidney disease (BKD) susceptibility in Lake Michigan Chinook Salmon and its progenitor population from the Puget Sound

    USGS Publications Warehouse

    Purcell, Maureen K.; Hard, Jeffrey J.; Neely, Kathleen G.; Park, Linda K.; Winton, James R.; Elliott, Diane G.

    2014-01-01

    Mass mortality events in wild fish due to infectious diseases are troubling, especially given the potential for long-term, population-level consequences. Evolutionary theory predicts that populations with sufficient genetic variation will adapt in response to pathogen pressure. Chinook Salmon Oncorhynchus tshawytscha were introduced into Lake Michigan in the late 1960s from a Washington State hatchery population. In the late 1980s, collapse of the forage base and nutritional stress in Lake Michigan were thought to contribute to die-offs of Chinook Salmon due to bacterial kidney disease (BKD). Previously, we demonstrated that Lake Michigan Chinook Salmon from a Wisconsin hatchery have greater survival following BKD challenge relative to their progenitor population. Here, we evaluated whether the phenotypic divergence of these populations in BKD susceptibility was due to selection rather than genetic drift. Comparison of the overall magnitude of quantitative trait to neutral marker divergence between the populations suggested selection had occurred but a direct test of quantitative trait divergence was not significant, preventing the rejection of the null hypothesis of differentiation through genetic drift. Estimates of phenotypic variation (VP), additive genetic variation (VA) and narrow-sense heritability (h2) were consistently higher in the Wisconsin relative to the Washington population. If selection had acted on the Wisconsin population there was no evidence of a concomitant loss of genetic variation in BKD susceptibility. The Renibacterium salmoninarum exposures were conducted at both 14°C and 9°C; the warmer temperature accelerated time to death in both populations and there was no evidence of phenotypic plasticity or a genotype-by-environment (G × E) interaction. High h2 estimates for BKD susceptibility in the Wisconsin population, combined with a lack of phenotypic plasticity, predicts that future adaptive gains in BKD resistance are still possible and

  6. DNA and allozyme markers provide concordant estimates of population differentiation: Analyses of U.S. and Canadian populations of Yukon River fall-run chum salmon (Oncorhynchus keta)

    USGS Publications Warehouse

    Scribner, K.T.; Crane, P.A.; Spearman, W.J.; Seeb, L.W.

    1998-01-01

    Although the number of genetic markers available for fisheries research has steadily increased in recent years, there is limited information on their relative utility. In this study, we compared the performance of different 'classes' of genetic markers (mitochondrial DNA (mtDNA), nuclear DNA (nDNA), and allozymes) in terms of estimating levels and partitioning of genetic variation and of the relative accuracy and precision in estimating population allocations to mixed-stock fisheries. Individuals from eight populations of fall-run chum salmon (Oncorhynchus keta) from the Yukon River in Alaska and Canada were assayed at 25 loci. Significant differences in mitochondrial haplotype and nuclear allele frequencies were observed among five drainages. Populations from the U.S.-Canada border region were not clearly distinguishable based on multilocus allele frequencies. Although estimates of total genetic diversities were higher for the DNA loci (H(t) = 0.592 and h = 0.647 for nDNA and mtDNA, respectively) compared with protein allozymes (H(t) = 0.250), estimates of the extent of population differentiation were highly concordant across marker classes (mean ?? = 0.010, 0.011, and 0.016 for allozymes, nDNA, and mtDNA, respectively). Simulations of mixed-stock fisheries composed of varying contributions of U.S. and Canadian populations revealed a consistent bias for overallocation of Canadian stocks when expected Canadian contributions varied from 0 to 40%, due primarily to misallocations among genetically similar border populations. No single marker class is superior for differentiating populations of this species at the spatial scale examined.

  7. Is population growth a deterrent to development in the South Pacific?

    PubMed

    Ahlburg, D A

    1988-05-01

    "Some have argued that population growth deters development, while others claim that population growth either aids development or has no significant effect on development. In a sample of South Pacific nations, population growth and size were found to be unrelated to economic development, defined as GDP per capita. However, when indices of quality of life or social development such as mortality, health services and education were used, population growth and size were found to be negatively related to these indices. If these 'quality of life' indices are valued by nations, an argument may exist for policy support for family planning."

  8. The road to extinction is paved with good intentions: negative association of fish hatcheries with threatened salmon.

    PubMed

    Levin, P S; Zabel, R W; Williams, J G

    2001-06-01

    Hatchery programmes for supplementing depleted populations of fish are undergoing a worldwide expansion and have provoked concern about their ramifications for populations of wild fish. In particular, Pacific salmon are artificially propagated in enormous numbers in order to compensate for numerous human insults to their populations, yet the ecological impacts of this massive hatchery effort are poorly understood. Here we test the hypothesis that massive numbers of hatchery-raised chinook salmon reduce the marine survival of wild Snake River spring chinook, a threatened species in the USA. Based on a unique 25-year time-series, we demonstrated a strong, negative relationship between the survival of chinook salmon and the number of hatchery fish released, particularly during years of poor ocean conditions. Our results suggest that hatchery programmes that produce increasingly higher numbers of fish may hinder the recovery of depleted wild populations.

  9. Population Genetics of an Ecosystem-Defining Reef Coral Pocillopora damicornis in the Tropical Eastern Pacific

    PubMed Central

    Combosch, David J.; Vollmer, Steven V.

    2011-01-01

    Background Coral reefs in the Tropical Eastern Pacific (TEP) are amongst the most peripheral and geographically isolated in the world. This isolation has shaped the biology of TEP organisms and lead to the formation of numerous endemic species. For example, the coral Pocillopora damicornis is a minor reef-builder elsewhere in the Indo-West Pacific, but is the dominant reef-building coral in the TEP, where it forms large, mono-specific stands, covering many hectares of reef. Moreover, TEP P. damicornis reproduces by broadcast spawning, while it broods mostly parthenogenetic larvae throughout the rest of the Indo-West Pacific. Population genetic surveys for P. damicornis from across its Indo-Pacific range indicate that gene flow (i.e. larval dispersal) is generally limited over hundreds of kilometers or less. Little is known about the population genetic structure and the dispersal potential of P. damicornis in the TEP. Methodology Using multilocus microsatellite data, we analyzed the population structure of TEP P. damicornis among and within nine reefs and test for significant genetic structure across three geographically and ecologically distinct regions in Panama. Principal Findings/Conclusions We detected significant levels of population genetic structure (global RST = 0.162), indicating restricted gene flow (i.e. larvae dispersal), both among the three regions (RRT = 0.081) as well as within regions (RSR = 0.089). Limited gene flow across a distinct environmental cline, like the regional upwelling gradient in Panama, indicates a significant potential for differential adaptation and population differentiation. Individual reefs were characterized by unexpectedly high genet diversity (avg. 94%), relatively high inbreeding coefficients (global FIS = 0.183), and localized spatial genetic structure among individuals (i.e. unique genets) over 10 m intervals. These findings suggest that gene flow is limited in TEP P. damicornis populations, particularly

  10. Discrimination among populations of sockeye salmon fry with Fourier analysis of otolith banding patterns formed during incubation

    USGS Publications Warehouse

    Finn, J.E.; Burger, C.V.; Holland-Bartels, L.

    1997-01-01

    We used otolith banding patterns formed during incubation to discriminate among hatchery- and wild-incubated fry of sockeye salmon Oncorhynchus nerka from Tustumena Lake, Alaska. Fourier analysis of otolith luminance profiles was used to describe banding patterns: the amplitudes of individual Fourier harmonics were discriminant variables. Correct classification of otoliths to either hatchery or wild origin was 83.1% (cross-validation) and 72.7% (test data) with the use of quadratic discriminant function analysts on 10 Fourier amplitudes. Overall classification rates among the six test groups (one hatchery and five wild groups) were 46.5% (cross-validation) and 39.3% (test data) with the use of linear discriminant function analysis on 16 Fourier amplitudes. Although classification rates for wild-incubated fry from any one site never exceeded 67% (cross-validation) or 60% (test data), location-specific information was evident for all groups because the probability of classifying an individual to its true incubation location was significantly greater than chance. Results indicate phenotypic differences in otolith microstructure among incubation sites separated by less than 10 km. Analysis of otolith luminance profiles is a potentially useful technique for discriminating among and between various populations of hatchery and wild fish.

  11. Renal disease disparities in Asian and Pacific-based populations in Hawai'i.

    PubMed

    Mau, Marjorie K; West, Margaret; Sugihara, Jared; Kamaka, Martina; Mikami, Judy; Cheng, Shiuh-Feng

    2003-10-01

    The prevalence of end-stage renal disease (ESRD) in the United States is expected to double over the next 10 years. The identification of ethnic differences in the prevalence, treatment, morbidity, and mortality related to chronic kidney disease (CKD) is of great concern. Asian Americans comprise a rapidly expanding sector of the U.S. population and are reported to have ESRD growth rates that are approximately 50% higher than caucasians. Hawai'i has a large, well-established Asian and Pacific-based population that facilitates the examination of disparities in renal disease among the state's diverse ethnic groups. The prevalence of ESRD in Hawai'i has continued to rise due, in part, to high rates of diabetes, glomerulonephritis, and hypertension reported in Asian Americans and Pacific-based populations. ESRD patients in Hawai'i have a two-fold higher prevalence of glomerulonephritis, compared with the general ESRD population in the United States. Other potential sources of renal disparities-such as cultural factors, language barriers, and health access factors-among Hawaii's major ethnic groups are assessed. However, few studies have examined the relative contribution of these potential factors. Consequently, efforts to reduce and eventually eliminate renal disease disparities will require a better understanding of the major sources of health disparities, such as timely medical care, a diverse health workforce, and cultural/social barriers, that affect optimal health care practices in Asian and Pacific-based populations. PMID:14620708

  12. Renal disease disparities in Asian and Pacific-based populations in Hawai'i.

    PubMed

    Mau, Marjorie K; West, Margaret; Sugihara, Jared; Kamaka, Martina; Mikami, Judy; Cheng, Shiuh-Feng

    2003-10-01

    The prevalence of end-stage renal disease (ESRD) in the United States is expected to double over the next 10 years. The identification of ethnic differences in the prevalence, treatment, morbidity, and mortality related to chronic kidney disease (CKD) is of great concern. Asian Americans comprise a rapidly expanding sector of the U.S. population and are reported to have ESRD growth rates that are approximately 50% higher than caucasians. Hawai'i has a large, well-established Asian and Pacific-based population that facilitates the examination of disparities in renal disease among the state's diverse ethnic groups. The prevalence of ESRD in Hawai'i has continued to rise due, in part, to high rates of diabetes, glomerulonephritis, and hypertension reported in Asian Americans and Pacific-based populations. ESRD patients in Hawai'i have a two-fold higher prevalence of glomerulonephritis, compared with the general ESRD population in the United States. Other potential sources of renal disparities-such as cultural factors, language barriers, and health access factors-among Hawaii's major ethnic groups are assessed. However, few studies have examined the relative contribution of these potential factors. Consequently, efforts to reduce and eventually eliminate renal disease disparities will require a better understanding of the major sources of health disparities, such as timely medical care, a diverse health workforce, and cultural/social barriers, that affect optimal health care practices in Asian and Pacific-based populations.

  13. How coarse is too coarse for salmon spawning substrates?

    NASA Astrophysics Data System (ADS)

    Wooster, J. K.; Riebe, C. S.; Ligon, F. K.; Overstreet, B. T.

    2009-12-01

    Populations of Pacific salmon species have declined sharply in many rivers of the western US. Reversing these declines is a top priority and expense of many river restoration projects. To help restore salmon populations, managers often inject gravel into rivers, to supplement spawning habitat that has been depleted by gravel mining and the effects of dams—which block sediment and thus impair habitat downstream by coarsening the bed where salmon historically spawned. However, there is little quantitative understanding nor a methodology for determining when a river bed has become too coarse for salmon spawning. Hence there is little scientific basis for selecting sites that would optimize the restoration benefits of gravel injection (e.g., sites where flow velocities are suitable but bed materials are too coarse for spawning). To develop a quantitative understanding of what makes river beds too coarse for salmon spawning, we studied redds and spawning use in a series of California and Washington rivers where salmon spawning ability appears to be affected by coarse bed material. Our working hypothesis is that for a given flow condition, there is a maximum “threshold” particle size that a salmon of a given size is able to excavate and/or move as she builds her redd. A second, related hypothesis is that spawning use should decrease and eventually become impossible with increasing percent coverage by immovable particles. To test these hypotheses, we quantified the sizes and spatial distributions of immovably coarse particles in a series of salmon redds in each river during the peak of spawning. We also quantified spawning use and how it relates to percent coverage by immovable particles. Results from our studies of fall-run chinook salmon (Oncorhynchus tshawytsha) in the Feather River suggest that immovable particle size varies as a function of flow velocity over the redd, implying that faster water helps fish move bigger particles. Our Feather River study also

  14. Linkage disequilibrium in wild and cultured populations of Pacific oyster ( Crassostrea gigas)

    NASA Astrophysics Data System (ADS)

    Guo, Xiang; Li, Qi; Kong, Lingfeng; Yu, Hong

    2016-04-01

    Linkage disequilibrium (LD) can be applied for mapping the actual genes responsible for variation of economically important traits through association mapping. The feasibility and efficacy of association studies are strongly dependent on the extent of LD which determines the number and density of markers in the studied population, as well as the experimental design for an association analysis. In this study, we first characterized the extent of LD in a wild population and a cultured mass-selected line of Pacific oyster ( Crassostrea gigas). A total of 88 wild and 96 cultured individuals were selected to assess the level of genome-wide LD with 53 microsatellites, respectively. For syntenic marker pairs, no significant association was observed in the wild population; however, three significant associations occurred in the cultured population, and the significant LD extended up to 12.7 cM, indicating that strong artificial selection is a key force for substantial increase of genome-wide LD in cultured population. The difference of LD between wild and cultured populations showed that association studies in Pacific oyster can be achieved with reasonable marker densities at a relatively low cost by choosing an association mapping population. Furthermore, the frequent occurrence of LD between non-syntenic loci and rare alleles encourages the joint application of linkage analysis and LD mapping when mapping genes in oyster. The information on the linkage disequilibrium in the cultured population is useful for future association mapping in oyster.

  15. Contributions of isolated Pacific populations to understanding neurodegenerative diseases.

    PubMed

    Garruto, Ralph M; Yanagihara, Richard

    2009-01-01

    Isolated human populations have provided a natural experimental laboratory for the ongoing study of human disease. In the mid-20th century a number of high-incidence foci of neurodegenerative diseases were brought to medical attention including kuru, amyotrophic lateral sclerosis, and parkinsonism-dementia. These foci were discovered in Papua New Guinea, West New Guinea, the Kii Peninsula of Japan, and in the Mariana Islands. The study of these diseases in isolated human groups has significantly contributed to our understanding of the cause and mechanisms of pathogenesis of these and related neurodegenerative disorders globally. This paper is dedicated to D. Carleton Gajdusek, a pioneer in the study of neurodegenerative diseases, whose decades of fieldwork and laboratory studies have led to numerous scientific discoveries that have reshaped our thinking and understanding about neurodegeneration.

  16. Population Education in Asia and the Pacific. Bulletin of the Unesco Regional Office for Education in Asia and the Pacific. Number 23, June, 1982.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and the Pacific.

    The necessity of successfully managing population and development to ensure the quality of life in Asia in the coming decade is emphasized in this bulletin, which is arranged into four sections. Section one contains an article dealing with change and development of population education in Asia and the Pacific and a demographic analysis. Section…

  17. Wild salmon in California, Oregon, Washington, and Idaho: Some recovery strategies that just might work

    EPA Science Inventory

    The primary goal of the Salmon 2100 Project is to identify salmon recovery options that have a high probability of maintaining biologically significant, sustainable populations of wild salmon in California, Oregon, Washington, Idaho, and southern British Columbia. The Project doe...

  18. Complex pattern of genetic structuring in the Atlantic salmon (Salmo salar L.) of the River Foyle system in northwest Ireland: disentangling the evolutionary signal from population stochasticity.

    PubMed

    Ensing, Dennis; Prodöhl, Paulo A; McGinnity, Philip; Boylan, Patrick; O'Maoiléidigh, Niall; Crozier, Walter W

    2011-11-01

    Little is known about the microevolutionary processes shaping within river population genetic structure of aquatic organisms characterized by high levels of homing and spawning site fidelity. Using a microsatellite panel, we observed complex and highly significant levels of intrariver population genetic substructure and Isolation-by-Distance, in the Atlantic salmon stock of a large river system. Two evolutionary models have been considered explaining mechanisms promoting genetic substructuring in Atlantic salmon, the member-vagrant and metapopulation models. We show that both models can be simultaneously used to explain patterns and levels of population structuring within the Foyle system. We show that anthropogenic factors have had a large influence on contemporary population structure observed. In an analytical development, we found that the frequently used estimator of genetic differentiation, F(ST), routinely underestimated genetic differentiation by a factor three to four compared to the equivalent statistic Jost's D(est) (Jost 2008). These statistics also showed a near-perfect correlation. Despite ongoing discussions regarding the usefulness of "adjusted"F(ST) statistics, we argue that these could be useful to identify and quantify qualitative differences between populations, which are important from management and conservation perspectives as an indicator of existence of biologically significant variation among tributary populations or a warning of critical environmental damage.

  19. Population structure of humpback whales in the western and central South Pacific Ocean as determined by vocal exchange among populations.

    PubMed

    Garland, Ellen C; Goldizen, Anne W; Lilley, Matthew S; Rekdahl, Melinda L; Garrigue, Claire; Constantine, Rochelle; Hauser, Nan Daeschler; Poole, M Michael; Robbins, Jooke; Noad, Michael J

    2015-08-01

    For cetaceans, population structure is traditionally determined by molecular genetics or photographically identified individuals. Acoustic data, however, has provided information on movement and population structure with less effort and cost than traditional methods in an array of taxa. Male humpback whales (Megaptera novaeangliae) produce a continually evolving vocal sexual display, or song, that is similar among all males in a population. The rapid cultural transmission (the transfer of information or behavior between conspecifics through social learning) of different versions of this display between distinct but interconnected populations in the western and central South Pacific region presents a unique way to investigate population structure based on the movement dynamics of a song (acoustic) display. Using 11 years of data, we investigated an acoustically based population structure for the region by comparing stereotyped song sequences among populations and years. We used the Levenshtein distance technique to group previously defined populations into (vocally based) clusters based on the overall similarity of their song display in space and time. We identified the following distinct vocal clusters: western cluster, 1 population off eastern Australia; central cluster, populations around New Caledonia, Tonga, and American Samoa; and eastern region, either a single cluster or 2 clusters, one around the Cook Islands and the other off French Polynesia. These results are consistent with the hypothesis that each breeding aggregation represents a distinct population (each occupied a single, terminal node) in a metapopulation, similar to the current understanding of population structure based on genetic and photo-identification studies. However, the central vocal cluster had higher levels of song-sharing among populations than the other clusters, indicating that levels of vocal connectivity varied within the region. Our results demonstrate the utility and value of

  20. Population structure of humpback whales in the western and central South Pacific Ocean as determined by vocal exchange among populations.

    PubMed

    Garland, Ellen C; Goldizen, Anne W; Lilley, Matthew S; Rekdahl, Melinda L; Garrigue, Claire; Constantine, Rochelle; Hauser, Nan Daeschler; Poole, M Michael; Robbins, Jooke; Noad, Michael J

    2015-08-01

    For cetaceans, population structure is traditionally determined by molecular genetics or photographically identified individuals. Acoustic data, however, has provided information on movement and population structure with less effort and cost than traditional methods in an array of taxa. Male humpback whales (Megaptera novaeangliae) produce a continually evolving vocal sexual display, or song, that is similar among all males in a population. The rapid cultural transmission (the transfer of information or behavior between conspecifics through social learning) of different versions of this display between distinct but interconnected populations in the western and central South Pacific region presents a unique way to investigate population structure based on the movement dynamics of a song (acoustic) display. Using 11 years of data, we investigated an acoustically based population structure for the region by comparing stereotyped song sequences among populations and years. We used the Levenshtein distance technique to group previously defined populations into (vocally based) clusters based on the overall similarity of their song display in space and time. We identified the following distinct vocal clusters: western cluster, 1 population off eastern Australia; central cluster, populations around New Caledonia, Tonga, and American Samoa; and eastern region, either a single cluster or 2 clusters, one around the Cook Islands and the other off French Polynesia. These results are consistent with the hypothesis that each breeding aggregation represents a distinct population (each occupied a single, terminal node) in a metapopulation, similar to the current understanding of population structure based on genetic and photo-identification studies. However, the central vocal cluster had higher levels of song-sharing among populations than the other clusters, indicating that levels of vocal connectivity varied within the region. Our results demonstrate the utility and value of

  1. The influence of male parr body size and mate competition on fertilization success and effective population size in Atlantic salmon.

    PubMed

    Jones, M W; Hutchings, J A

    2001-06-01

    Alternative mating strategies in male Atlantic salmon, Salmo salar, are characterized by variability in body size and mate competition. Controlling breeding numbers of larger, older anadromous males, we examined whether body size of mature male parr influenced fertilization success and whether such an association was affected by mate competition among parr. Variation at three to four hypervariable microsatellite loci was used to determine individual paternity of 53-60 offspring from two or three nests from each experimental treatment. Although individual and total parr reproductive success differed significantly among nests within treatments, there was no relationship between parr size and individual reproductive success at any level of competition when anadromous males were involved. However, in a single treatment having no anadromous male, the influence of body size on parr fertilization success was highly significant. Combining data from all treatments, parr body size was an important predictor of the probability of an individual being involved in spawning. We found a negative relationship between total parr reproductive success and intensity of anadromous male competition. To our knowledge, the present study is the first to estimate the effective number of males from individual fertilization success in fish. Our estimates of Ne should not be taken as absolute and may have a downward bias because we did not sample all nests and we used a proxy for lifetime reproductive success. They do, however, illustrate how mature male parr can greatly increase the effective number of males when the latter is estimated from anadromous individuals alone. Although reproductive success by mature male parr increases the effective number of males, this increase seems likely to be most pronounced in natural populations when the number of anadromous males is low.

  2. An assessment of oil-spill effects on pink salmon populations following the Exxon Valdez oil spill. Part 2: Adults and escapement

    SciTech Connect

    Maki, A.W.; Brannon, E.J.; Gilbertson, L.G.; Moulton, L.L.; Skalski, J.R.

    1995-12-31

    This paper presents results of a field program designed to monitor the status of wildstock pink salmon populations in Prince William Sound following the Exxon Valdez oil spill. Field counts of spawning salmon were conducted each year from 1989 through 1992 to test for spill effects o the distribution nd abundance of pink salmon adults spawning in selected streams in the southwestern portion of Prince William Sound, including streams from the most heavily oiled areas. Counts of whole-stream and intertidal escapement density were statistically compared for 40 study streams in 1989 and for a subset of those streams in successive years. Measurements of residual hydrocarbons were made from stream-bed sediments to test for correlations with spawning behavior. Adult pink salmon in the postspill years of 1990 and 1991, progeny of the year classes considered most vulnerable to the oil spill, returned in high numbers, with the wildstock spawners exceeding their parent year returns. In 1989, adult returns reflected the relatively weak run for that year with a mean spawner density of 0.68 fish/m{sup 2} in reference streams and 0.69 fish/m{sup 2} in oiled streams. In 1990, mean escapement density for reference streams was 1.40 fish/m{sup 2} and 1.55 fish/m{sup 2} for oiled streams, indicating the strongest run of the four study years. Trends in polycyclic aromatic hydrocarbon (PAH) concentrations for the majority of oiled streams show a general decline from 1989 to background levels by 1990. 45 refs., 14 figs., 5 tabs.

  3. Power of QTL mapping experiments in commercial Atlantic salmon populations, exploiting linkage and linkage disequilibrium and effect of limited recombination in males.

    PubMed

    Hayes, B J; Gjuvsland, A; Omholt, S

    2006-07-01

    Whereas detection and positioning of genes that affect quantitative traits (quantitative trait loci (QTL)) using linkage mapping uses only information from recombinants in the genotyped generations, linkage disequilibrium (LD) mapping uses historical recombinants. Thus, whereas linkage mapping requires large family sizes to detect and accurately position QTL, LD mapping is more dependent on the number of families sampled from the population. In commercial Atlantic salmon breeding programmes, only a small number of individuals per family are routinely phenotyped for traits such as disease resistance and meat colour. In this paper, we assess the power and accuracy of combined linkage disequilibrium linkage analysis (LDLA) to detect QTL in the commercial population using simulation. When 15 half-sib sire families (each sire mated to 30 dams, each dam with 10 progeny) were sampled from the population for genotyping, we were able to detect a QTL explaining 10% of the phenotypic variance in 85% of replicates and position this QTL within 3 cM of the true position in 70% of replicates. When recombination was absent in males, a feature of the salmon genome, power to detect QTL increased; however, the accuracy of positioning the QTL was decreased. By increasing the number of sire families sampled from the population to be genotyped to 30, we were able to increase both the proportion of QTL detected and correctly positioned (even with no recombination in males). QTL with much smaller effect could also be detected. The results suggest that even with the existing recording structure in commercial salmon breeding programmes, there is considerable power to detect and accurately position QTL using LDLA. PMID:16685283

  4. Fine-scale population genetic structure in Alaskan Pacific halibut (Hippoglossus stenolepis)

    USGS Publications Warehouse

    2010-01-01

    Pacific halibut collected in the Aleutian Islands, Bering Sea and Gulf of Alaska were used to test the hypothesis of genetic panmixia for this species in Alaskan marine waters. Nine microsatellite loci and sequence data from the mitochondrial (mtDNA) control region were analyzed. Eighteen unique mtDNA haplotypes were found with no evidence of geographic population structure. Using nine microsatellite loci, significant heterogeneity was detected between Aleutian Island Pacific halibut and fish from the other two regions (FST range = 0.007–0.008). Significant FST values represent the first genetic evidence of divergent groups of halibut in the central and western Aleutian Archipelago. No significant genetic differences were found between Pacific halibut in the Gulf of Alaska and the Bering Sea leading to questions about factors contributing to separation of Aleutian halibut. Previous studies have reported Aleutian oceanographic conditions at deep inter-island passes leading to ecological discontinuity and unique community structure east and west of Aleutian passes. Aleutian Pacific halibut genetic structure may result from oceanographic transport mechanisms acting as partial barriers to gene flow with fish from other Alaskan waters.

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

    USGS Publications Warehouse

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

  6. 78 FR 49259 - Pacific Fishery Management Council; Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-13

    ... (Pacific Council) will convene a meeting of the Salmon Technical Team (STT), the Salmon Advisory Subpanel...-2280. SUPPLEMENTARY INFORMATION: Please note, this is not a public hearing; it is a work session...

  7. Salmon-Eating Grizzly Bears Exposed to Elevated Levels of Marine Derived Persistent Organic Pollutants

    NASA Astrophysics Data System (ADS)

    Christensen, J. R.; Ross, P. S.; Whiticar, M. J.

    2004-12-01

    The coastal grizzly bears of British Columbia (BC, Canada) rely heavily on salmon returning from the Pacific Ocean, whereas interior bears do not have access to or readily utilize this marine-derived food source. Since salmon have been shown to accumulate persistent organic pollutants (POPs) from the North Pacific Ocean, we hypothesized that salmon consumption by grizzly bears would be reflected by an increase in the POP burden. To test this hypothesis we collected hair and fat tissue from grizzlies at various locations around BC to compare salmon-eating (coastal) grizzlies to non-salmon-eating (interior) grizzlies. We characterized the feeding habits for each bear sampled by measuring the stable carbon and nitrogen isotope signature of their hair. The positive relationship between 13C/12C and 15N/14N isotopic ratios suggests that the majority of the meat portion of the diet of coastal grizzlies is coming from salmon, rather than from terrestrial or freshwater sources. By contrast, stable isotope ratios revealed that interior bears have an almost exclusive vegetarian diet with no marine influence. As hypothesized, the coastal grizzly bears have significantly greater OC pesticide and lower-brominated PBDE congener body burden than the interior grizzlies. We also found a positive relationship between C and N isotope ratios and these same POP contaminants in bear tissue. Overall, these results demonstrate that Pacific salmon represents a significant vector delivering both OC pesticides and PBDEs to BC coastal grizzly bears.

  8. Teratological hermaphroditism in the chum salmon Oncorhynchus keta (Walbaum)

    USGS Publications Warehouse

    Uzmann, J.R.; Hesselholt, M.N.

    1957-01-01

    The anomalous condition of hermaphroditism appears to be no less rare in fish than in other normally dioecious animals. Previous records of bisexuality' in the Pacific salmons, Oncorhynchus spp., are few in number despite the intensive study accorded this group. Rutter (1902) reported the condition in two king salmon (O. tshawytscha); Crawford (1927) reported the condition in a silver salmon (O. kisutch); and Gibbs (1956) described a bisexual steelhead trout (Salmo gairdneri) and briefly noted another instance of hermaphroditism in the king salmon. We wish to record an example of this anomaly in the chum salmon (O. keta).

  9. Nuclear and mitochondrial patterns of population structure in North Pacific false killer whales (Pseudorca crassidens).

    PubMed

    Martien, Karen K; Chivers, Susan J; Baird, Robin W; Archer, Frederick I; Gorgone, Antoinette M; Hancock-Hanser, Brittany L; Mattila, David; McSweeney, Daniel J; Oleson, Erin M; Palmer, Carol; Pease, Victoria L; Robertson, Kelly M; Schorr, Gregory S; Schultz, Mark B; Webster, Daniel L; Taylor, Barbara L

    2014-01-01

    False killer whales (Pseudorca crassidens) are large delphinids typically found in deep water far offshore. However, in the Hawaiian Archipelago, there are 2 resident island-associated populations of false killer whales, one in the waters around the main Hawaiian Islands (MHI) and one in the waters around the Northwestern Hawaiian Islands (NWHI). We use mitochondrial DNA (mtDNA) control region sequences and genotypes from 16 nuclear DNA (nucDNA) microsatellite loci from 206 individuals to examine levels of differentiation among the 2 island-associated populations and offshore animals from the central and eastern North Pacific. Both mtDNA and nucDNA exhibit highly significant differentiation between populations, confirming limited gene flow in both sexes. The mtDNA haplotypes exhibit a strong pattern of phylogeographic concordance, with island-associated populations sharing 3 closely related haplotypes not found elsewhere in the Pacific. However, nucDNA data suggest that NWHI animals are at least as differentiated from MHI animals as they are from offshore animals. The patterns of differentiation revealed by the 2 marker types suggest that the island-associated false killer whale populations likely share a common colonization history, but have limited contemporary gene flow. PMID:24831238

  10. Nuclear and mitochondrial patterns of population structure in North Pacific false killer whales (Pseudorca crassidens).

    PubMed

    Martien, Karen K; Chivers, Susan J; Baird, Robin W; Archer, Frederick I; Gorgone, Antoinette M; Hancock-Hanser, Brittany L; Mattila, David; McSweeney, Daniel J; Oleson, Erin M; Palmer, Carol; Pease, Victoria L; Robertson, Kelly M; Schorr, Gregory S; Schultz, Mark B; Webster, Daniel L; Taylor, Barbara L

    2014-01-01

    False killer whales (Pseudorca crassidens) are large delphinids typically found in deep water far offshore. However, in the Hawaiian Archipelago, there are 2 resident island-associated populations of false killer whales, one in the waters around the main Hawaiian Islands (MHI) and one in the waters around the Northwestern Hawaiian Islands (NWHI). We use mitochondrial DNA (mtDNA) control region sequences and genotypes from 16 nuclear DNA (nucDNA) microsatellite loci from 206 individuals to examine levels of differentiation among the 2 island-associated populations and offshore animals from the central and eastern North Pacific. Both mtDNA and nucDNA exhibit highly significant differentiation between populations, confirming limited gene flow in both sexes. The mtDNA haplotypes exhibit a strong pattern of phylogeographic concordance, with island-associated populations sharing 3 closely related haplotypes not found elsewhere in the Pacific. However, nucDNA data suggest that NWHI animals are at least as differentiated from MHI animals as they are from offshore animals. The patterns of differentiation revealed by the 2 marker types suggest that the island-associated false killer whale populations likely share a common colonization history, but have limited contemporary gene flow.

  11. Climatic Change and Marine Ecosystems in the NE Pacific: A Holocene Perspective

    NASA Astrophysics Data System (ADS)

    Finney, B. P.; Addison, J. A.

    2006-12-01

    more abundant during the little ice age (c.a. 1200 - 1900 AD). Correspondence between these records and paleoclimatic data suggest that changes in salmon abundance are related to large- scale climatic changes over the North Pacific. For example, the increase in salmon abundance c.a. 1200 AD corresponds to a period of glacial advance in southern Alaska, and a shift to drier conditions in western North America. However, climate-salmon relationships do not always follow patterns observed in the 20th century. Historically, Alaska salmon abundance is generally high during periods of warm SST (positive PDO). Consistent with this pattern, records of reconstructed sockeye salmon generally show higher abundance during warm periods over the past 300 years. However, the long-term trend suggests higher average abundance during the generally cooler Little Ice Age. Thus records of ocean productivity, which generally correlate with salmon abundance, may provide a mechanistic linkage between climate change and salmon populations.

  12. 76 FR 76386 - Endangered and Threatened Species; 5-Year Reviews for 4 Distinct Population Segments of Steelhead...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-07

    ... Pacific salmon ESUs and steelhead DPSs in California, Oregon, Washington, and Idaho (75 FR 13082). Both... Reviews for 4 Distinct Population Segments of Steelhead in California AGENCY: National Marine Fisheries... Viable Salmonid Population framework, which relies on evaluating four key population...

  13. Morphological changes in the retina in Pacific ocean salmon Oncorhynchus masou fry in response to neutralization of the geomagnetic field in conditions of normal illumination.

    PubMed

    Maksimovich, A A; Kondrashev, S L; Gnyubkina, V P

    2008-10-01

    The studies reported here provide the first demonstration that retinal responses in both the fry of the migratory salmon trout Oncorhynchus masou and the dwarf form of this species changed in conditions of experimental neutralization of the geomagnetic field (GMF); migratory salmon trout fry and dwarves showed different changes. The responses of different types of retinal photoreceptor in migratory salmon trout fry to neutralization of the GMF differed: while rods and double cones perceived neutralization of the GMF as the onset of darkness (the scotopic reaction), single (generally blue-sensitive) cones responded to neutralization of the GMF both as presentation of blue light or (very rarely) ultraviolet irradiation. The retina of dwarf male salmon trout responded to neutralization of the GMF with a double response: rods showed a light (photopic) response, while double (red/green-sensitive) cones produced dark (scotopic) responses. Single (blue-sensitive) cones responded to neutralization of the GMF as bright blue light. Thus, the morphological picture of the retina in dwarf male salmon trout in these experimental conditions corresponds to the perception of blue light. The initial conditions were different--normal diffuse daylight with a brightness of about 7.5 Lx. It is likely that neutralization of the magnetic field had no effect on rods, while double, red-green, cones responded as to darkness, i.e., the fish did not perceive red or green light in the visible spectrum, but perceived only blue and, possibly, ultraviolet light by means of central blue-sensitive and accessory cones. Thus, these experiments demonstrated that in conditions of normal daylight illumination, retinal photoreceptors in salmon fry respond to changes in the earth's magnetic field, i.e., objectively function as magnetoreceptors.

  14. Recovery of sockeye salmon in the Elwha River, Washington, after dam removal: Dependence of smolt production on the resumption of anadromy by landlocked kokanee

    USGS Publications Warehouse

    Hansen, Adam G.; Gardner, Jennifer R.; Beauchamp, David A.; Paradis, Rebecca; Quinn, Thomas P

    2016-01-01

    Pacific salmon Oncorhynchus spp. are adept at colonizing habitat that has been reopened to anadromous passage. Sockeye Salmon O. nerka are unique in that most populations require lakes to fulfill their life history. Thus, for Sockeye Salmon to colonize a system, projects like dam removals must provide access to lakes. However, if the lakes contain landlocked kokanee (lacustrine Sockeye Salmon), the recovery of Sockeye Salmon could be mediated by interactions between the two life history forms and the processes associated with the resumption of anadromy. Our objective was to evaluate the extent to which estimates of Sockeye Salmon smolt production and recovery are sensitive to the resumption of anadromy by kokanee after dam removal. We informed the analysis based on the abiotic and biotic features of Lake Sutherland, which was recently opened to passage after dam removal on the Elwha River, Washington. We first developed maximum expectations for the smolt-producing capacity of Lake Sutherland by using two predictive models developed from Sockeye Salmon populations in Alaska and British Columbia: one model was based on the mean seasonal biomass of macrozooplankton, and the other was based on the euphotic zone volume of the lake. We then constructed a bioenergetics-based simulation model to evaluate how the capacity of Lake Sutherland to rear yearling smolts could change with varying degrees of anadromy among O. nerka fry. We demonstrated that (1) the smolt-producing capacity of a nursery lake for juvenile Sockeye Salmon changes in nonlinear ways with changes in smolt growth, mortality, and the extent to which kokanee resume anadromy after dam removal; (2) kokanee populations may be robust to changes in abundance after dam removal, particularly if lakes are located higher in the watershed on tributaries separate from where dams were removed; and (3) the productivity of newly establishing Sockeye Salmon can vary considerably depending on whether the population becomes

  15. Contrasting Genetic Structure among Populations of Two Amphidromous Fish Species (Sicydiinae) in the Central West Pacific

    PubMed Central

    Taillebois, Laura; Castelin, Magalie; Ovenden, Jennifer R.; Bonillo, Céline; Keith, Philippe

    2013-01-01

    Both present-day and past processes can shape connectivity of populations. Pleistocene vicariant events and dispersal have shaped the present distribution and connectivity patterns of aquatic species in the Indo-Pacific region. In particular, the processes that have shaped distribution of amphidromous goby species still remain unknown. Previous studies show that phylogeographic breaks are observed between populations in the Indian and Pacific Oceans where the shallow Sunda shelf constituted a geographical barrier to dispersal, or that the large spans of open ocean that isolate the Hawaiian or Polynesian Islands are also barriers for amphidromous species even though they have great dispersal capacity. Here we assess past and present genetic structure of populations of two amphidromous fish (gobies of the Sicydiinae) that are widely distributed in the Central West Pacific and which have similar pelagic larval durations. We analysed sections of mitochondrial COI, Cytb and nuclear Rhodospine genes in individuals sampled from different locations across their entire known range. Similar to other Sicydiinae fish, intraspecific mtDNA genetic diversity was high for all species (haplotype diversity between 0.9–0.96). Spatial analyses of genetic variation in Sicyopus zosterophorum demonstrated strong isolation across the Torres Strait, which was a geologically intermittent land barrier linking Australia to Papua New Guinea. There was a clear genetic break between the northwestern and the southwestern clusters in Si. zosterophorum (φST = 0.67502 for COI) and coalescent analyses revealed that the two populations split at 306 Kyr BP (95% HPD 79–625 Kyr BP), which is consistent with a Pleistocene separation caused by the Torres Strait barrier. However, this geographical barrier did not seem to affect Sm. fehlmanni. Historical and demographic hypotheses are raised to explain the different patterns of population structure and distribution between these species. Strategies

  16. Oceanic interchange and nonequilibrium population structure in the estuarine dependent Indo-Pacific tasselfish, Polynemus sheridani.

    PubMed

    Chenoweth, Stephen F; Hughes, Jane M

    2003-09-01

    We assayed mtDNA haplotype [300 base pairs (bp) control region] geography and genealogy in the Indo-Pacific tasselfish, Polynemus sheridani from its contiguous estuarine distribution across northern Australia (n = 169). Eight estuaries were sampled from three oceanographic regions (Timor Sea, Gulf of Carpentaria and the Coral Sea) to assess the impact of Pleistocene sea level changes on the historical connectivity among P. sheridani populations. Specifically, we investigated the genetic consequences of disruption to Indian-Pacific Ocean connectivity brought about by the closure of the Torres Strait. Overall there was significant population subdivision among estuaries (FST = 0.161, PhiST = 0.187). Despite a linear distribution, P. sheridani did not show isolation by distance over the entire sampled range because of genetic similarity of estuaries greater than 3000 km apart. However, significant isolation by distance was detected between estuaries separated by less than 3000 km of coastline. Unlike many genetic studies of Indo-Pacific marine species, there was no evidence for an historical division between eastern and western populations. Instead, phylogeographical patterns were dominated by a starlike intraspecific phylogeny coupled with evidence for population expansion in both the Gulf of Carpentaria and the Coral Sea but not the Timor Sea. This was interpreted as evidence for recent west to east recolonization across of northern Australia following the last postglacial marine advance. We argue that although sufficient time has elapsed postcolonization for populations to approach gene flow-drift equilibrium over smaller spatial scales (< 3000 km), the signal of historical colonization persists to obscure the expected equilibrium pattern of isolation by distance over large spatial scales (> 3000 km). PMID:12919476

  17. Contrasting genetic structure among populations of two amphidromous fish species (Sicydiinae) in the Central West Pacific.

    PubMed

    Taillebois, Laura; Castelin, Magalie; Ovenden, Jennifer R; Bonillo, Céline; Keith, Philippe

    2013-01-01

    Both present-day and past processes can shape connectivity of populations. Pleistocene vicariant events and dispersal have shaped the present distribution and connectivity patterns of aquatic species in the Indo-Pacific region. In particular, the processes that have shaped distribution of amphidromous goby species still remain unknown. Previous studies show that phylogeographic breaks are observed between populations in the Indian and Pacific Oceans where the shallow Sunda shelf constituted a geographical barrier to dispersal, or that the large spans of open ocean that isolate the Hawaiian or Polynesian Islands are also barriers for amphidromous species even though they have great dispersal capacity. Here we assess past and present genetic structure of populations of two amphidromous fish (gobies of the Sicydiinae) that are widely distributed in the Central West Pacific and which have similar pelagic larval durations. We analysed sections of mitochondrial COI, Cytb and nuclear Rhodospine genes in individuals sampled from different locations across their entire known range. Similar to other Sicydiinae fish, intraspecific mtDNA genetic diversity was high for all species (haplotype diversity between 0.9-0.96). Spatial analyses of genetic variation in Sicyopus zosterophorum demonstrated strong isolation across the Torres Strait, which was a geologically intermittent land barrier linking Australia to Papua New Guinea. There was a clear genetic break between the northwestern and the southwestern clusters in Si. zosterophorum (φST = 0.67502 for COI) and coalescent analyses revealed that the two populations split at 306 Kyr BP (95% HPD 79-625 Kyr BP), which is consistent with a Pleistocene separation caused by the Torres Strait barrier. However, this geographical barrier did not seem to affect Sm. fehlmanni. Historical and demographic hypotheses are raised to explain the different patterns of population structure and distribution between these species. Strategies

  18. Contrasting genetic structure among populations of two amphidromous fish species (Sicydiinae) in the Central West Pacific.

    PubMed

    Taillebois, Laura; Castelin, Magalie; Ovenden, Jennifer R; Bonillo, Céline; Keith, Philippe

    2013-01-01

    Both present-day and past processes can shape connectivity of populations. Pleistocene vicariant events and dispersal have shaped the present distribution and connectivity patterns of aquatic species in the Indo-Pacific region. In particular, the processes that have shaped distribution of amphidromous goby species still remain unknown. Previous studies show that phylogeographic breaks are observed between populations in the Indian and Pacific Oceans where the shallow Sunda shelf constituted a geographical barrier to dispersal, or that the large spans of open ocean that isolate the Hawaiian or Polynesian Islands are also barriers for amphidromous species even though they have great dispersal capacity. Here we assess past and present genetic structure of populations of two amphidromous fish (gobies of the Sicydiinae) that are widely distributed in the Central West Pacific and which have similar pelagic larval durations. We analysed sections of mitochondrial COI, Cytb and nuclear Rhodospine genes in individuals sampled from different locations across their entire known range. Similar to other Sicydiinae fish, intraspecific mtDNA genetic diversity was high for all species (haplotype diversity between 0.9-0.96). Spatial analyses of genetic variation in Sicyopus zosterophorum demonstrated strong isolation across the Torres Strait, which was a geologically intermittent land barrier linking Australia to Papua New Guinea. There was a clear genetic break between the northwestern and the southwestern clusters in Si. zosterophorum (φST = 0.67502 for COI) and coalescent analyses revealed that the two populations split at 306 Kyr BP (95% HPD 79-625 Kyr BP), which is consistent with a Pleistocene separation caused by the Torres Strait barrier. However, this geographical barrier did not seem to affect Sm. fehlmanni. Historical and demographic hypotheses are raised to explain the different patterns of population structure and distribution between these species. Strategies

  19. Identification of distinct movement patterns in Pacific leatherback turtle populations influenced by ocean conditions.

    PubMed

    Bailey, Helen; Benson, Scott R; Shillinger, George L; Bograd, Steven J; Dutton, Peter H; Eckert, Scott A; Morreale, Stephen J; Paladino, Frank V; Eguchi, Tomoharu; Foley, David G; Block, Barbara A; Piedra, Rotney; Hitipeuw, Creusa; Tapilatu, Ricardo F; Spotila, James R

    2012-04-01

    Interactions with fisheries are believed to be a major cause of mortality for adult leatherback turtles (Dermochelys coriacea), which is of particular concern in the Pacific Ocean, where they have been rapidly declining. In order to identify where these interactions are occurring and how they may be reduced, it is essential first to understand the movements and behavior of leatherback turtles. There are two regional nesting populations in the East Pacific (EP) and West Pacific (WP), comprising multiple nesting sites. We synthesized tracking data from the two populations and compared their movement patterns. A switching state-space model was applied to 135 Argos satellite tracks to account for observation error, and to distinguish between migratory and area-restricted search behaviors. The tracking data, from the largest leatherback data set ever assembled, indicated that there was a high degree of spatial segregation between EP and WP leatherbacks. Area-restricted search behavior mainly occurred in the southeast Pacific for the EP leatherbacks, whereas the WP leatherbacks had several different search areas in the California Current, central North Pacific, South China Sea, off eastern Indonesia, and off southeastern Australia. We also extracted remotely sensed oceanographic data and applied a generalized linear mixed model to determine if leatherbacks exhibited different behavior in relation to environmental variables. For the WP population, the probability of area-restricted search behavior was positively correlated with chlorophyll-a concentration. This response was less strong in the EP population, but these turtles had a higher probability of search behavior where there was greater Ekman upwelling, which may increase the transport of nutrients and consequently prey availability. These divergent responses to oceanographic conditions have implications for leatherback vulnerability to fisheries interactions and to the effects of climate change. The occurrence of

  20. Identification of distinct movement patterns in Pacific leatherback turtle populations influenced by ocean conditions.

    PubMed

    Bailey, Helen; Benson, Scott R; Shillinger, George L; Bograd, Steven J; Dutton, Peter H; Eckert, Scott A; Morreale, Stephen J; Paladino, Frank V; Eguchi, Tomoharu; Foley, David G; Block, Barbara A; Piedra, Rotney; Hitipeuw, Creusa; Tapilatu, Ricardo F; Spotila, James R

    2012-04-01

    Interactions with fisheries are believed to be a major cause of mortality for adult leatherback turtles (Dermochelys coriacea), which is of particular concern in the Pacific Ocean, where they have been rapidly declining. In order to identify where these interactions are occurring and how they may be reduced, it is essential first to understand the movements and behavior of leatherback turtles. There are two regional nesting populations in the East Pacific (EP) and West Pacific (WP), comprising multiple nesting sites. We synthesized tracking data from the two populations and compared their movement patterns. A switching state-space model was applied to 135 Argos satellite tracks to account for observation error, and to distinguish between migratory and area-restricted search behaviors. The tracking data, from the largest leatherback data set ever assembled, indicated that there was a high degree of spatial segregation between EP and WP leatherbacks. Area-restricted search behavior mainly occurred in the southeast Pacific for the EP leatherbacks, whereas the WP leatherbacks had several different search areas in the California Current, central North Pacific, South China Sea, off eastern Indonesia, and off southeastern Australia. We also extracted remotely sensed oceanographic data and applied a generalized linear mixed model to determine if leatherbacks exhibited different behavior in relation to environmental variables. For the WP population, the probability of area-restricted search behavior was positively correlated with chlorophyll-a concentration. This response was less strong in the EP population, but these turtles had a higher probability of search behavior where there was greater Ekman upwelling, which may increase the transport of nutrients and consequently prey availability. These divergent responses to oceanographic conditions have implications for leatherback vulnerability to fisheries interactions and to the effects of climate change. The occurrence of

  1. Temporal variation in selection on body length and date of return in a wild population of coho salmon, Oncorhynchus kisutch

    PubMed Central

    2012-01-01

    Background A number of studies have measured selection in nature to understand how populations adapt to their environment; however, the temporal dynamics of selection are rarely investigated. The aim of this study was to assess the temporal variation in selection by comparing the mode, direction and strength of selection on fitness-related traits between two cohorts of coho salmon (Oncorhynchus kisutch). Specifically, we quantified individual reproductive success and examined selection on date of return and body length in a wild population at Big Beef Creek, Washington (USA). Results Reproductive success and the mode, direction and strength of selection on date of return and body length differed between two cohorts sampled in 2006 and 2007. Adults of the first brood year had greater success over those of the second. In 2006, disruptive selection favored early and late returning individuals in 2-year-old males, and earlier returning 3-year-old males had higher fitness. No evidence of selection on date of return was detected in females. In 2007, selection on date of return was not observed in males of either age class, but stabilizing selection on date of return was observed in females. No selection on body length was detected in males of both age classes in 2006, and large size was associated with higher fitness in females. In 2007, selection favored larger size in 3-year-old males and intermediate size in females. Correlational selection between date of return and body length was observed only in 2-year-old males in 2006. Conclusions We found evidence of selection on body length and date of return to the spawning ground, both of which are important fitness-related traits in salmonid species, but this selection varied over time. Fluctuation in the mode, direction and strength of selection between two cohorts was likely to be due to factors such as changes in precipitation, occurrence of catastrophic events (flooding), the proportion of younger- versus older

  2. Influence of multiple dam passage on survival of juvenile Chinook salmon in the Columbia River estuary and coastal ocean.

    PubMed

    Rechisky, Erin L; Welch, David W; Porter, Aswea D; Jacobs-Scott, Melinda C; Winchell, Paul M

    2013-04-23

    Multiple dam passage during seaward migration is thought to reduce the subsequent survival of Snake River Chinook salmon. This hypothesis developed because juvenile Chinook salmon from the Snake River, the Columbia River's largest tributary, migrate >700 km through eight hydropower dams and have lower adult return rates than downstream populations that migrate through only 3 or 4 dams. Using a large-scale telemetry array, we tested whether survival of hatchery-reared juvenile Snake River spring Chinook salmon is reduced in the estuary and coastal ocean relative to a downstream, hatchery-reared population from the Yakima River. During the initial 750-km, 1-mo-long migration through the estuary and coastal ocean, we found no evidence of differential survival; therefore, poorer adult returns of Snake River Chinook may develop far from the Columbia River. Thus, hydrosystem mitigation efforts may be ineffective if differential mortality rates develop in the North Pacific Ocean for reasons unrelated to dam passage.

  3. Influence of multiple dam passage on survival of juvenile Chinook salmon in the Columbia River estuary and coastal ocean.

    PubMed

    Rechisky, Erin L; Welch, David W; Porter, Aswea D; Jacobs-Scott, Melinda C; Winchell, Paul M

    2013-04-23

    Multiple dam passage during seaward migration is thought to reduce the subsequent survival of Snake River Chinook salmon. This hypothesis developed because juvenile Chinook salmon from the Snake River, the Columbia River's largest tributary, migrate >700 km through eight hydropower dams and have lower adult return rates than downstream populations that migrate through only 3 or 4 dams. Using a large-scale telemetry array, we tested whether survival of hatchery-reared juvenile Snake River spring Chinook salmon is reduced in the estuary and coastal ocean relative to a downstream, hatchery-reared population from the Yakima River. During the initial 750-km, 1-mo-long migration through the estuary and coastal ocean, we found no evidence of differential survival; therefore, poorer adult returns of Snake River Chinook may develop far from the Columbia River. Thus, hydrosystem mitigation efforts may be ineffective if differential mortality rates develop in the North Pacific Ocean for reasons unrelated to dam passage. PMID:23576733

  4. Salmon 2100: Some recovery strategies that just might work

    EPA Science Inventory

    The primary goal of the Salmon 2100 Project is to identify practical options that have a high probability of maintaining biologically significant, sustainable populations of wild salmon in California, Oregon, Washington, Idaho, and southern British Columbia. The Project does not ...

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

    SciTech Connect

    Flagg, Thomas A.

    2001-01-01

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

  6. Preliminary forecasts of Pacific bigeye tuna population trends under the A2 IPCC scenario

    NASA Astrophysics Data System (ADS)

    Lehodey, P.; Senina, I.; Sibert, J.; Bopp, L.; Calmettes, B.; Hampton, J.; Murtugudde, R.

    2010-07-01

    An improved version of the spatial ecosystem and population dynamics model SEAPODYM was used to investigate the potential impacts of global warming on tuna populations. The model included an enhanced definition of habitat indices, movements, and accessibility of tuna predators to different vertically migrant and non-migrant micronekton functional groups. The simulations covered the Pacific basin (model domain) at a 2° × 2° geographic resolution. The structure of the model allows an evaluation from multiple data sources, and parameterization can be optimized by adjoint techniques and maximum likelihood using fishing data. A first such optimized parameterization was obtained for bigeye tuna ( Thunnus obesus) in the Pacific Ocean using historical catch data for the last 50 years and a hindcast from a coupled physical-biogeochemical model driven by the NCEP atmospheric reanalysis. The parameterization provided very plausible biological parameter values and a good fit to fishing data from the different fisheries, both within and outside the time period used for optimization. We then employed this model to forecast the future of bigeye tuna populations in the Pacific Ocean. The simulation was driven by the physical-biogeochemical fields predicted from a global marine biogeochemistry - climate simulation. This global simulation was performed with the IPSL climate model version 4 (IPSL-CM4) coupled to the oceanic biogeochemical model PISCES and forced by atmospheric CO 2, from historical records over 1860-2000, and under the SRES A2 IPCC scenario for the 21st century (i.e. atmospheric CO 2 concentration reaching 850 ppm in the year 2100). Potential future changes in distribution and abundance under the IPCC scenario are presented but without taking into account any fishing effort. The simulation showed an improvement in bigeye tuna spawning habitat both in subtropical latitudes and in the eastern tropical Pacific (ETP) where the surface temperature becomes optimal for

  7. Partial migration in introduced wild chinook salmon (Oncorhynchus tshawytscha) of southern Chile

    NASA Astrophysics Data System (ADS)

    Araya, Miguel; Niklitschek, Edwin J.; Secor, Dave H.; Piccoli, Philip M.

    2014-08-01

    Partial migration, the incidence of opposing migration behaviors within the same population, has been a key factor in the invasive ecology of Pacific salmon within South America. Here, we examined such life-cycle variation in of an introduced chinook salmon population in the Aysén watershed, one of the largest fjord systems in NW Patagonia. The chinook salmon is the most successful invasive salmonid species in Patagonia and has recently colonized numerous Patagonian watersheds of the Pacific and Atlantic Oceans. Using analyses of fish scales and otolith strontium:calcium ratios, our results suggest the presence of two distinct ecotypes in the chinook population, an ocean type and a stream type, in a 3:2 ratio. The distribution of back-calculated length at the time of emigration from river to marine habitats showed a mode of 14 cm for the ocean ecotype and 30 cm for the stream ecotype. River residence time for the ocean ecotype ranged from 1 to 10 months, while that of the stream ecotype varied between 14 and 20 months. Returning adults reproduced in riverine habitats between August and March, but reproduction by the stream ecotype was limited to the period between October and February. Our results show that exotic chinook salmon populations established in NW Patagonia present a diversity of life-history strategies, which seems to be as large as the ones exhibited by the species in its native distribution range and in other invaded ecosystems. Chinook salmon have successfully invaded most major rivers in Patagonia, placing priority on science and conservation related to their ecological impact.

  8. Genetic and phenotypic changes in an Atlantic salmon population supplemented with non-local individuals: a longitudinal study over 21 years

    PubMed Central

    Le Cam, Sabrina; Perrier, Charles; Besnard, Anne-Laure; Bernatchez, Louis; Evanno, Guillaume

    2015-01-01

    While introductions and supplementations using non-native and potentially domesticated individuals may have dramatic evolutionary effects on wild populations, few studies documented the evolution of genetic diversity and life-history traits in supplemented populations. Here, we investigated year-to-year changes from 1989 to 2009 in genetic admixture at 15 microsatellite loci and in phenotypic traits in an Atlantic salmon (Salmo salar) population stocked during the first decade of this period with two genetically and phenotypically distinct source populations. We detected a pattern of temporally increasing introgressive hybridization between the stocked population and both source populations. The proportion of fish returning to the river after a single winter at sea (versus several ones) was higher in fish assigned to the main source population than in local individuals. Moreover, during the first decade of the study, both single-sea-winter and multi-sea-winter (MSW) fish assigned to the main source population were smaller than local fish. During the second decade of the study, MSW fish defined as hybrids were lighter and smaller than fish from parental populations, suggesting outbreeding depression. Overall, this study suggests that supplementation with non-local individuals may alter not only the genetic diversity of wild populations but also life-history traits of adaptive significance. PMID:25608883

  9. Comparative phylogeny and historical perspectives on population genetics of the Pacific hawksbill (Eretmochelys imbricata) and green turtles (Chelonia mydas), inferred from feeding populations in the Yaeyama Islands, Japan.

    PubMed

    Nishizawa, Hideaki; Okuyama, Junichi; Kobayashi, Masato; Abe, Osamu; Arai, Nobuaki

    2010-01-01

    Mitochondrial DNA sequence polymorphisms and patterns of genetic diversity represent the genealogy and relative impacts of historical, geographic, and demographic events on populations. In this study, historical patterns of population dynamics and differentiation in hawksbill (Eretmochelys imbricata) and green turtles (Chelonia mydas) in the Pacific were estimated from feeding populations in the Yaeyama Islands, Japan. Phylogenetic relationships of the haplotypes indicated that hawksbill and green turtles in the Pacific probably underwent very similar patterns and processes of population dynamics over the last million years, with population subdivision during the early Pleistocene and population expansion after the last glacial maximum. These significant contemporary historical events were suggested to have been caused by climatic and sea-level fluctuations. On the other hand, comparing our results to long-term population dynamics in the Atlantic, population subdivisions during the early Pleistocene were specific to Pacific hawksbill and green turtles. Therefore, regional differences in historical population dynamics are suggested. Despite limited sampling locations, these results are the first step in estimating the historical trends in Pacific sea turtles by using phylogenetics and population genetics.

  10. The Genetic Structure of Staphylococcus aureus Populations from the Southwest Pacific

    PubMed Central

    Ritchie, Stephen R.; Thomas, Mark G.; Rainey, Paul B.

    2014-01-01

    The genetic structure of Staphylococcus aureus populations sampled from diverse regions of the globe have been the subject of numerous investigations. Here we describe the structure of S. aureus populations collected from the Southwest Pacific. Multi-locus sequence typing was performed on 467 isolates obtained from people with nasal colonization or bacteremia in Auckland (NZ), and patients predominantly affected by skin and soft tissue infection in Samoa, Fiji and Tonga. The predominant sequence types (STs) varied between Auckland (ST5), Fiji (ST30), and Samoa (ST1), however, the overall genetic diversity within each region did not differ significantly between locations. Divergent Clonal Complex 75 (CC75) strains were isolated in Auckland and Fiji. When diversity of the Southwest Pacific populations was compared with those previously described from Asia, Europe, North America and Africa no significant differences were detected. With the exception of CC75 strains, the global collection of S. aureus encompasses relatively little diversity, with novel STs arising locally from a small number of widespread lineages. PMID:25003509

  11. Discovery and characterization of single nucleotide polymorphisms in coho salmon, Oncorhynchus kisutch.

    PubMed

    Starks, Hilary A; Clemento, Anthony J; Garza, John Carlos

    2016-01-01

    Molecular population genetic analyses have become an integral part of ecological investigation and population monitoring for conservation and management. Microsatellites have been the molecular marker of choice for such applications over the last several decades, but single nucleotide polymorphism (SNP) markers are rapidly expanding beyond model organisms. Coho salmon (Oncorhynchus kisutch) is native to the north Pacific Ocean and its tributaries, where it is the focus of intensive fishery and conservation activities. As it is an anadromous species, coho salmon typically migrate across multiple jurisdictional boundaries, complicating management and requiring shared data collection methods. Here, we describe the discovery and validation of a suite of novel SNPs and associated genotyping assays which can be used in the genetic analyses of this species. These assays include 91 that are polymorphic in the species and one that discriminates it from a sister species, Chinook salmon. We demonstrate the utility of these SNPs for population assignment and phylogeographic analyses, and map them against the draft trout genome. The markers constitute a large majority of all SNP markers described for coho salmon and will enable both population- and pedigree-based analyses across the southern part of the species native range. PMID:25965351

  12. Morphological and reproductive variation among populations of the Pacific molly Poecilia butleri.

    PubMed

    Zúñiga-Vega, J J; Suárez-Rodríguez, M; Espinosa-Pérez, H; Johnson, J B

    2011-10-01

    In viviparous organisms, pregnant females typically experience an increase in body mass and body volume. In this study, the prediction that variation in reproductive traits among populations of viviparous organisms should be related to variation among populations in body shape was tested in the Pacific molly Poecilia butleri, a viviparous fish that inhabits western Mexico and northern Central America. Variation among 10 populations in four reproductive traits was examined: brood size, individual embryo mass, total reproductive allotment and degree of maternal provisioning of nutrients to developing embryos. Variation among these populations in body shape was also examined. Significant variation among populations was observed in both brood size and reproductive allotment but not in embryo mass or degree of maternal provisioning. Significant variation among populations was also observed in body shape. After correcting for female size, however, reproductive traits and body shape were not associated among populations. This suggests that selective pressures acting on reproduction do not necessarily affect morphology and vice versa. Several factors might contribute to this unexpected lack of association between reproductive traits and morphology.

  13. Habitat Suitability Index Models: Coho salmon

    USGS Publications Warehouse

    McMahon, Thomas E.

    1983-01-01

    The coho salmon (Oncorhynchus kisutch) is native to the northern Pacific Ocean, spawning and rearing in streams from Monterey Bay, California, to Point Hope, Alaska, and southward along the Asiatic coast to Japan. Its center of abundance in North America is from Oregon to Alaska (Briggs 1953; Godfrey 1965; Hart 1973; Scott and Crossman 1973). Coho salmon have been successfully introduced into the Great Lakes and reservoirs and lakes throughout the United States to provide put-and-grow sport fishing (Scott and Crossman 1973; Wigglesworth and Rawson 1974). No subspecies of coho salmon have been described (Godfrey 1965).

  14. Analysis of microsatellite DNA markers reveals no genetic differentiation between wild and hatchery populations of Pacific threadfin in Hawaii.

    PubMed

    Pan, Gang; Yang, Jinzeng

    2010-01-01

    Pacific threadfin, Polydactylus sexfilis, is popular fish in recreational fishing, as well as aquaculture in Hawaii. Its natural population has been continuously declining in the past several decades. Microsatellite DNA markers are useful DNA-based tool for monitoring Pacific threadfin populations. In this study, fifteen Microsatellite (MS) DNA markers were identified from a partial genomic Pacific threadfin DNA library enriched in CA repeats, and six highly-polymorphic microsatellite loci were employed to analyze genetic similarity and differences between the wild population and hatchery population in Oahu Island. A total of 37 alleles were detected at the six MS loci in the two populations. Statistical analysis of fixation index (F(ST)) and analysis of molecular variance (AMOVA) showed no genetic differentiation between the wild and hatchery populations (F(ST) = 0.001, CI(95%) = -0.01-0.021). Both high genetic diversity (H(o) = 0.664-0.674 and H(e) = 0.710-0.715) and Hardy-Weinberg equilibrium were observed in the wild and hatchery populations. Results of genetic bottleneck analysis indicated that the hatchery was founded with sufficient numbers of brooders as inbreeding coefficient is very low (F(IS) = 0.052-0.072) in both wild and hatchery populations. Further studies are needed for comprehensive determinations of genetic varieties of primary founder broodstocks and successive offspring of the hatchery and wild populations with increased number of Pacific threadfin sample collections.

  15. Linking physical monitoring to coho and Chinook salmon populations in the Redwood Creek Watershed, California—Summary of May 3–4, 2012 Workshop

    USGS Publications Warehouse

    Madej, Mary Ann; Torregrosa, Alicia; Woodward, Andrea

    2012-01-01

    On Thursday, May 3, 2012, a science workshop was held at the Redwood National and State Parks (RNSP) office in Arcata, California, with researchers and resource managers working in RNSP to share data and expert opinions concerning salmon populations and habitat in the Redwood Creek watershed. The focus of the workshop was to discuss how best to synthesize physical and biological data related to the freshwater and estuarine phases of salmon life cycles in order to increase the understanding of constraints on salmon populations. The workshop was hosted by the U.S. Geological Survey (USGS) Status and Trends (S&T) Program National Park Monitoring Project (http://www.fort.usgs.gov/brdscience/ParkMonitoring.htm), which supports USGS research on priority topics (themes) identified by the National Park Service (NPS) Inventory and Monitoring Program (I&M) and S&T. The NPS has organized more than 270 parks with significant natural resources into 32 Inventory and Monitoring (I&M) Networks (http://science.nature.nps.gov/im/networks.cfm) that share funding and core professional staff to monitor the status and long-term trends of selected natural resources (http://science.nature.nps.gov/im/monitor). All 32 networks have completed vital signs monitoring plans (available at http://science.nature.nps.gov/im/monitor/MonitoringPlans.cfm), containing background information on the important resources of each park, conceptual models behind the selection of vital signs for monitoring the condition of natural resources, and the selection of high priority vital signs for monitoring. Vital signs are particular physical, chemical, and biological elements and processes of park ecosystems that represent the overall health or condition of the park, known or hypothesized effects of stressors, or elements that have important human values (Fancy and others, 2009). Beginning in 2009, the I&M program funded projects to analyze and synthesize the biotic and abiotic data generated by vital signs

  16. Limnology and fish ecology of sockeye salmon nursery lakes of the world

    USGS Publications Warehouse

    Hartman, Wilbur L.; Burgner, R.L.

    1972-01-01

    Many important, recently glaciated oligotrophic lakes that lie in coastal regions around the northern rim of the Pacific Ocean produce anadromous populations of sockeye salmon, Oncorhynchus nerka. This paper describes the limnology and fish ecology of two such lakes in British Columbia, five in Alaska, and one in Kamchatka. Then we discuss the following general topics: the biogenic eutrophication of nursery lakes from the nutrients released from salmon carcasses wherein during years of highest numbers of spawners, lake phosphate balances in Lakes Babine, Iliamna, and Dalnee are significantly affected; the use of nursery lakes by young sockeye that reveals five patterns related to size and configuration of lake basins and the distribution of spawning areas; the interactions between various life history stages of sockeye salmon and such resident predators, competitors, and prey as Arctic char, lake trout, Dolly Varden, cutthroat trout, lake whitefish, pygmy whitefish, pond smelt, sticklebacks, and sculpins; the self-regulation of sockeye salmon abundance in these nursery lakes as controlled by density-dependent processes; the interrelations between young sockeye salmon biomass and growth rates, and zooplankton abundance in Babine Lake; and finally, the diel, vertical, pelagial migratory behavior of young sockeye in Babine Lake and the new hypothesis dealing with bioenergetic conservation.

  17. Genome-wide SNP analysis reveals a genetic basis for sea-age variation in a wild population of Atlantic salmon (Salmo salar).

    PubMed

    Johnston, Susan E; Orell, Panu; Pritchard, Victoria L; Kent, Matthew P; Lien, Sigbjørn; Niemelä, Eero; Erkinaro, Jaakko; Primmer, Craig R

    2014-07-01

    Delaying sexual maturation can lead to larger body size and higher reproductive success, but carries an increased risk of death before reproducing. Classical life history theory predicts that trade-offs between reproductive success and survival should lead to the evolution of an optimal strategy in a given population. However, variation in mating strategies generally persists, and in general, there remains a poor understanding of genetic and physiological mechanisms underlying this variation. One extreme case of this is in the Atlantic salmon (Salmo salar), which can show variation in the age at which they return from their marine migration to spawn (i.e. their 'sea age'). This results in large size differences between strategies, with direct implications for individual fitness. Here, we used an Illumina Infinium SNP array to identify regions of the genome associated with variation in sea age in a large population of Atlantic salmon in Northern Europe, implementing individual-based genome-wide association studies (GWAS) and population-based FST outlier analyses. We identified several regions of the genome which vary in association with phenotype and/or selection between sea ages, with nearby genes having functions related to muscle development, metabolism, immune response and mate choice. In addition, we found that individuals of different sea ages belong to different, yet sympatric populations in this system, indicating that reproductive isolation may be driven by divergence between stable strategies. Overall, this study demonstrates how genome-wide methodologies can be integrated with samples collected from wild, structured populations to understand their ecology and evolution in a natural context.

  18. Freshwater movement patterns by juvenile Pacific salmon Oncorhynchus spp. before they migrate to the ocean: Oh the places you'll go!

    PubMed

    Shrimpton, J M; Warren, K D; Todd, N L; McRae, C J; Glova, G J; Telmer, K H; Clarke, A D

    2014-10-01

    Juvenile movement patterns for coho salmon Oncorhynchus kisutch and Chinook salmon Oncorhynchus tshawytscha from two large interior rivers of British Columbia, Canada, were examined. Otoliths from post-spawned fishes were collected on spawning grounds and elemental signatures were determined through transects from sectioned otoliths using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS). Large variations in otolith elemental signatures were found during the freshwater life stage indicative of movement downstream to rivers and tributaries that differed in elemental signature. This study highlights that downstream movements occur before migration to the ocean during the parr-smolt transformation. Extensive downstream movements of parr appear to be a successful life-history strategy based on variations observed in the otolith elemental signatures of spawners. Movements downstream in parr and the remarkable homing ability of adults also suggest that imprinting to natal streams must occur prior to the parr-smolt transformation. PMID:25053226

  19. Potential population-level effects of increased haulout-related mortality of Pacific walrus calves

    USGS Publications Warehouse

    Udevitz, Mark S.; Taylor, Rebecca L.; Garlich-Miller, Joel L.; Quakenbush, Lori T.; Snyder, Jonathan A.

    2013-01-01

    Availability of summer sea ice has been decreasing in the Chukchi Sea during recent decades, and increasing numbers of Pacific walruses have begun using coastal haulouts in late summer during years when sea ice retreats beyond the continental shelf. Calves and yearlings are particularly susceptible to being crushed during disturbance events that cause the herd to panic and stampede at these large haulouts, but the potential population-level effects of this mortality are unknown. We used recent harvest data, along with previous assumptions about demographic parameters for this population, to estimate female population size and structure in 2009 and project these numbers forward using a range of assumptions about future harvests and haulout-related mortality that might result from increased use of coastal haulouts during late summer. We found that if demographic parameters were held constant, the levels of harvest that occurred during 1990–2008 would have allowed the population to grow during that period. Our projections indicate, however, that an increase in haulout-related mortality affecting only calves has a greater effect on the population than an equivalent increase in harvest-related mortality distributed among all age classes. Therefore, disturbance-related mortality of calves at coastal haulouts may have relatively important population consequences.

  20. Population trends in northern spotted owls: Associations with climate in the Pacific Northwest

    USGS Publications Warehouse

    Glenn, E.M.; Anthony, R.G.; Forsman, E.D.

    2010-01-01

    We used reverse time capture-mark-recapture models to describe associations between rate of population change (??) and climate for northern spotted owls (Strix occidentalis caurina) at six long-term study areas in Washington and Oregon, USA. Populations in three of six areas showed strong evidence of declining populations, while populations in two additional areas were likely declining as well. At four areas, ?? was positively associated with wetter-than-normal conditions during the growing season, which likely affects prey availability. Lambda was also negatively associated with cold, wet winters and nesting seasons, and the number of hot summer days. The amount of annual variation in ?? accounted for by climate varied across study areas (3-85%). Rate of population change was more sensitive to adult survival than to recruitment; however, there was considerable variation among years and across study areas for all demographic rates. While annual survival was more closely related to regional climate conditions, recruitment was often associated with local weather. In addition to climate, declines in recruitment at four of six areas were associated with increased presence of barred owls. Climate change models predict warmer, wetter winters and hotter, drier summers for the Pacific Northwest in the first half of the 21st century. Our results indicate that these conditions have the potential to negatively affect annual survival, recruitment, and consequently population growth rates for northern spotted owls. ?? 2010 Elsevier Ltd.

  1. Prevalence and secular trends in obesity in Pacific and Indian Ocean island populations.

    PubMed

    Hodge, A M; Dowse, G K; Zimmet, P Z; Collins, V R

    1995-09-01

    Surveys conducted in 10 Pacific island populations and in the multiethnic populations of Mauritius and Rodrigues in the Indian Ocean have provided data on the prevalence of obesity, potential etiological factors and medical hazards associated with obesity. The results indicate that the prevalence of obesity (by body mass index (BMI) in some of these populations is among the highest in the world. Obesity related to degree of modernization is more common in urban than in rural locations and tends to be found more often in women. In two populations where longitudinal data were available, there were dramatic increases in prevalence over relatively short time periods. Obesity contributed to the risk of non-insulin-dependent diabetes mellitus (NIDDM) and was associated with other risk factors for cardiovascular disease (CVD) in all populations, but no relationship could be found with total mortality in three ethnic groups for whom data were available. A genetic susceptibility to obesity combined with social pressures that favor high energy intakes and reduced physical activity are believed to be important in these populations. The challenge for the future lies in developing culturally appropriate programs for preventing obesity and thus reducing associated morbidity, while continuing to research its behavioral and genetic determinants. PMID:8581792

  2. Winter fidelity and apparent survival of lesser snow goose populations in the Pacific flyway

    USGS Publications Warehouse

    Williams, C.K.; Samuel, M.D.; Baranyuk, Vasily V.; Cooch, E.G.; Kraege, Donald K.

    2008-01-01

    populations. Face staining was an unreliable indicator of wintering area. Our findings suggest that northern and southern Wrangel Island subpopulations should be considered a metapopulation in better understanding and managing Pacific Flyway lesser snow geese. Yet the absence of a strong population connection between Banks Island and Wrangel Island geese suggests that these breeding colonies can be managed as separate but overlapping populations. Additionally, winter population fidelity may be more important in lesser snow geese than in other species, and both breeding and wintering areas are important components of population management for sympatric wintering populations.

  3. Consequences of acute stress and cortisol manipulation on the physiology, behavior, and reproductive outcome of female Pacific salmon on spawning grounds.

    PubMed

    McConnachie, Sarah H; Cook, Katrina V; Patterson, David A; Gilmour, Kathleen M; Hinch, Scott G; Farrell, Anthony P; Cooke, Steven J

    2012-06-01

    Life-history theory predicts that stress responses should be muted to maximize reproductive fitness. Yet, the relationship between stress and reproduction for semelparous salmon is unusual because successfully spawning individuals have elevated plasma cortisol levels. To tease apart the effects of high baseline cortisol levels and stress-induced elevation of cortisol titers, we determined how varying degrees of cortisol elevation (i.e., acute and chronic) affected behavior, reproductive physiology, and reproductive success of adult female pink salmon (Oncorhynchus gorbuscha) relative to different states of ovulation (i.e., ripe and unripe). Exhaustive exercise and air exposure were applied as acute stressors to manipulate plasma cortisol in salmon either confined to a behavioral arena or free-swimming in a spawning channel. Cortisol (eliciting a cortisol elevation to levels similar to those in post-spawn female salmon) and metyrapone (a corticosteroid synthesis inhibitor) implants were also used to chemically manipulate plasma cortisol. Cortisol implants elevated plasma cortisol, and impaired reproductive success; cortisol-treated fish released fewer eggs and died sooner than fish in other treatment groups. In contrast, acute stressors elevated plasma cortisol and the metyrapone implant suppressed plasma cortisol, but neither treatment significantly altered reproductive success, behavior, or physiology. Our results suggest that acute stressors do not influence behavior or reproductive outcome when experienced upon arrival at spawning grounds. Thus, certain critical aspects of salmonid reproduction can become refractory to various stressful conditions on spawning grounds. However, there is a limit to the ability of these fish to tolerate elevated cortisol levels as revealed by experimental elevation of cortisol.

  4. SALMON AND THE ENDANGERED SPECIES ACT: TROUBLESOME QUESTIONS

    EPA Science Inventory

    Throughout the Pacific Northwest and California, all wild salmon runs have declined since 1850 and some have disappeared. A sustainable future for wild salmon remains elusive. In response to requirements of the U.S. Endangered Species Act, the Canadian Species at Risk Act, and ...

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

    SciTech Connect

    Trudel, Marc; Tucker, Strahan; Morris, John

    2009-03-09

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

  6. Bedform morphology of salmon spawning areas in a large gravel-bed river

    SciTech Connect

    Hanrahan, Timothy P.

    2007-05-01

    While the importance of river channel morphology to salmon spawning habitat is increasingly recognized, quantitative measures of the relationships between channel morphology and habitat use are lacking. Such quantitative measures are necessary as management and regulatory agencies within the Pacific Northwestern region of the USA, and elsewhere, seek to quantify potential spawning habitat and develop recovery goals for declining salmon populations. The objective of this study was to determine if fall Chinook salmon (Oncorhynchus tshawytscha) spawning areas in the Snake River, Idaho, USA, were correlated with specific bed form types at the pool-riffle scale. A bed form differencing technique was used to objectively quantify the longitudinal riverbed profile into four distinct pool-riffle units that were independent of discharge. The vertical location of thalweg points within these units was quantified with a riffle proximity index. Chinook salmon spawning areas were mapped and correlated with the pool-riffle units through the use of cross-tabulation tables. The results indicate that 84% of fall Chinook salmon spawning areas were correlated with riffles (Chi-square=152.1, df=3, p<0.001), with 53% of those areas located on the upstream side of riffle crests. The majority of Snake River fall Chinook salmon spawning occurred at a vertical location within 80% of the nearest riffle crest elevation. The analyses of bed form morphology will assist regional fish mangers in quantifying existing and potential fall Chinook salmon spawning habitat, and will provide a quantitative framework for evaluating general ecological implications of channel morphology in large gravel-bed rivers.

  7. Competing conservation objectives for predators and prey: estimating killer whale prey requirements for Chinook salmon.

    PubMed

    Williams, Rob; Krkošek, Martin; Ashe, Erin; Branch, Trevor A; Clark, Steve; Hammond, Philip S; Hoyt, Erich; Noren, Dawn P; Rosen, David; Winship, Arliss

    2011-01-01

    Ecosystem-based management (EBM) of marine resources attempts to conserve interacting species. In contrast to single-species fisheries management, EBM aims to identify and resolve conflicting objectives for different species. Such a conflict may be emerging in the northeastern Pacific for southern resident killer whales (Orcinus orca) and their primary prey, Chinook salmon (Oncorhynchus tshawytscha). Both species have at-risk conservation status and transboundary (Canada-US) ranges. We modeled individual killer whale prey requirements from feeding and growth records of captive killer whales and morphometric data from historic live-capture fishery and whaling records worldwide. The models, combined with caloric value of salmon, and demographic and diet data for wild killer whales, allow us to predict salmon quantities needed to maintain and recover this killer whale population, which numbered 87 individuals in 2009. Our analyses provide new information on cost of lactation and new parameter estimates for other killer whale populations globally. Prey requirements of southern resident killer whales are difficult to reconcile with fisheries and conservation objectives for Chinook salmon, because the number of fish required is large relative to annual returns and fishery catches. For instance, a U.S. recovery goal (2.3% annual population growth of killer whales over 28 years) implies a 75% increase in energetic requirements. Reducing salmon fisheries may serve as a temporary mitigation measure to allow time for management actions to improve salmon productivity to take effect. As ecosystem-based fishery management becomes more prevalent, trade-offs between conservation objectives for predators and prey will become increasingly necessary. Our approach offers scenarios to compare relative influence of various sources of uncertainty on the resulting consumption estimates to prioritise future research efforts, and a general approach for assessing the extent of conflict

  8. Competing Conservation Objectives for Predators and Prey: Estimating Killer Whale Prey Requirements for Chinook Salmon

    PubMed Central

    Williams, Rob; Krkošek, Martin; Ashe, Erin; Branch, Trevor A.; Clark, Steve; Hammond, Philip S.; Hoyt, Erich; Noren, Dawn P.; Rosen, David; Winship, Arliss

    2011-01-01

    Ecosystem-based management (EBM) of marine resources attempts to conserve interacting species. In contrast to single-species fisheries management, EBM aims to identify and resolve conflicting objectives for different species. Such a conflict may be emerging in the northeastern Pacific for southern resident killer whales (Orcinus orca) and their primary prey, Chinook salmon (Oncorhynchus tshawytscha). Both species have at-risk conservation status and transboundary (Canada–US) ranges. We modeled individual killer whale prey requirements from feeding and growth records of captive killer whales and morphometric data from historic live-capture fishery and whaling records worldwide. The models, combined with caloric value of salmon, and demographic and diet data for wild killer whales, allow us to predict salmon quantities needed to maintain and recover this killer whale population, which numbered 87 individuals in 2009. Our analyses provide new information on cost of lactation and new parameter estimates for other killer whale populations globally. Prey requirements of southern resident killer whales are difficult to reconcile with fisheries and conservation objectives for Chinook salmon, because the number of fish required is large relative to annual returns and fishery catches. For instance, a U.S. recovery goal (2.3% annual population growth of killer whales over 28 years) implies a 75% increase in energetic requirements. Reducing salmon fisheries may serve as a temporary mitigation measure to allow time for management actions to improve salmon productivity to take effect. As ecosystem-based fishery management becomes more prevalent, trade-offs between conservation objectives for predators and prey will become increasingly necessary. Our approach offers scenarios to compare relative influence of various sources of uncertainty on the resulting consumption estimates to prioritise future research efforts, and a general approach for assessing the extent of conflict

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  10. Population Growth of Pratylenchus penetrans on Winter Cover Crops Grown in the Pacific Northwest

    PubMed Central

    Forge, T. A.; Ingham, R. E.; Kaufman, D.; Pinkerton, J. N.

    2000-01-01

    Population growth of Pratylenchus penetrans on 13 fall and winter cover crops was studied in the greenhouse and field. All crops except oat cv. Saia supported population growth of P. penetrans in greenhouse experiments, although the response of P. penetrans to oat cv. Saia varied considerably between experiments. The mean ratio of the final population density/initial population density (Pf/Pi) after 16 weeks for P. penetrans added to a greenhouse soil mix was 0.09, whereas Pf/Pi values after 10 weeks for two experiments with naturally infested soil were 0.95 and 2.3. Although P. penetrans increased on sudangrass cv. Trudan 8 and sudangrass × sorghum hybrid cv. SS 222, subsequent incorporation of sudangrass vegetation into soil reduced P. penetrans populations to preplant levels. Field experiments were inconclusive but suggested that oat cv. Saia or rye cv. Wheeler may be better choices for winter cover than weed-contaminated fallow or other crops on P. penetrans-infested sites in the Pacific Northwest. PMID:19270948

  11. Population trends in Pacific Oceanic sharks and the utility of regulations on shark finning.

    PubMed

    Clarke, Shelley C; Harley, Shelton J; Hoyle, Simon D; Rice, Joel S

    2013-02-01

    Accurate assessment of shark population status is essential for conservation but is often constrained by limited and unreliable data. To provide a basis for improved management of shark resources, we analyzed a long-term record of species-specific catches, sizes, and sexes of sharks collected by onboard observers in the western and central Pacific Ocean from 1995 to 2010. Using generalized linear models, we estimated population-status indicators on the basis of catch rate and biological indicators of fishing pressure on the basis of median size to identify trends for blue (Prionace glauca), mako (Isurus spp.), oceanic whitetip (Carcharhinus longimanus), and silky (Carcharhinus falciformis) sharks. Standardized catch rates of longline fleets declined significantly for blue sharks in the North Pacific (by 5% per year [CI 2% to 8%]), for mako sharks in the North Pacific (by 7% per year [CI 3% to 11%]), and for oceanic whitetip sharks in tropical waters (by 17% per year [CI 14% to 20%]). Median lengths of silky and oceanic whitetip sharks decreased significantly in their core habitat, and almost all sampled silky sharks were immature. Our results are consistent with results of analyses of similar data sets. Combined, these results and evidence of targeted fishing for sharks in some regional fisheries heighten concerns for sustainable utilization, particularly for oceanic whitetip and North Pacific blue sharks. Regional regulations that prohibit shark finning (removal of fins and discarding of the carcass) were enacted in 2007 and are in many cases the only form of control on shark catches. However, there is little evidence of a reduction of finning in longline fisheries. In addition, silky and oceanic whitetip sharks are more frequently retained than finned, which suggests that even full implementation of and adherence to a finning prohibition may not substantially reduce mortality rates for these species. We argue that finning prohibitions divert attention from

  12. Population trends in Pacific Oceanic sharks and the utility of regulations on shark finning.

    PubMed

    Clarke, Shelley C; Harley, Shelton J; Hoyle, Simon D; Rice, Joel S

    2013-02-01

    Accurate assessment of shark population status is essential for conservation but is often constrained by limited and unreliable data. To provide a basis for improved management of shark resources, we analyzed a long-term record of species-specific catches, sizes, and sexes of sharks collected by onboard observers in the western and central Pacific Ocean from 1995 to 2010. Using generalized linear models, we estimated population-status indicators on the basis of catch rate and biological indicators of fishing pressure on the basis of median size to identify trends for blue (Prionace glauca), mako (Isurus spp.), oceanic whitetip (Carcharhinus longimanus), and silky (Carcharhinus falciformis) sharks. Standardized catch rates of longline fleets declined significantly for blue sharks in the North Pacific (by 5% per year [CI 2% to 8%]), for mako sharks in the North Pacific (by 7% per year [CI 3% to 11%]), and for oceanic whitetip sharks in tropical waters (by 17% per year [CI 14% to 20%]). Median lengths of silky and oceanic whitetip sharks decreased significantly in their core habitat, and almost all sampled silky sharks were immature. Our results are consistent with results of analyses of similar data sets. Combined, these results and evidence of targeted fishing for sharks in some regional fisheries heighten concerns for sustainable utilization, particularly for oceanic whitetip and North Pacific blue sharks. Regional regulations that prohibit shark finning (removal of fins and discarding of the carcass) were enacted in 2007 and are in many cases the only form of control on shark catches. However, there is little evidence of a reduction of finning in longline fisheries. In addition, silky and oceanic whitetip sharks are more frequently retained than finned, which suggests that even full implementation of and adherence to a finning prohibition may not substantially reduce mortality rates for these species. We argue that finning prohibitions divert attention from

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

    SciTech Connect

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

    1990-03-01

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

  14. A Literature Review, Bibliographic Listing, and Organization of Selected References Relative to Pacific salmon (Oncorhynchus spp.) and Abiotic and Biotic Attributes of the Columbia River Estuary and Adjacent Marine and Riverine Environs for Various Historical Periods : Measure 7.1A of the Northwest Power Planning Council`s 1994 Fish and Wildlife Program : Report 4 of 4, Final Report.

    SciTech Connect

    Costello, Ronald J.

    1996-05-01

    This report contains the results of a literature review on the carrying capacity of Pacific salmon in the Columbia River Basin. The objective of the review was to find the information gaps relative to the determinants of salmon carrying capacity in the Columbia River Basin. The review was one activity designed to answer questions asked in Measure 7.1A of the Councils Fish and Wildlife Program. Based, in part, on the information learned during the literature review and the other work accomplished during this study the Pacific Northwest National Laboratory (PNNL) state concluded that the approach inherent in 7.1A will not increase understanding of ecology, carrying capacity, or limiting factors that influence salmon under current conditions. To increase understanding of ecology, carring capacity, and limiting factors, it is necessary to deal with the complexity of the sustained performance of salmon in the Columbia River Basin. The PNNL team suggests that the regions evaluated carrying capacity from more than one view point. The PNNL team recommends that the region use the contextualistic view for evaluating capacity.

  15. Changes in Size and Age of Chinook Salmon Oncorhynchus tshawytscha Returning to Alaska.

    PubMed

    Lewis, Bert; Grant, W Stewart; Brenner, Richard E; Hamazaki, Toshihide

    2015-01-01

    The average sizes of Pacific salmon have declined in some areas in the Northeast Pacific over the past few decades, but the extent and geographic distribution of these declines in Alaska is uncertain. Here, we used regression analyses to quantify decadal trends in length and age at maturity in ten datasets from commercial harvests, weirs, and spawner abundance surveys of Chinook salmon Oncorhynchus tshawytscha throughout Alaska. We found that on average these fish have become smaller over the past 30 years (~6 generations), because of a decline in the predominant age at maturity and because of a decrease in age-specific length. The proportion of older and larger 4-ocean age fish in the population declined significantly (P < 0.05) in all stocks examined by return year or brood year. Our analyses also indicated that the age-specific lengths of 4-ocean fish (9 of 10 stocks) and of 3-ocean fish (5 of 10 stocks) have declined significantly (P < 0.05). Size-selective harvest may be driving earlier maturation and declines in size, but the evidence is not conclusive, and additional factors, such as ocean conditions or competitive interactions with other species of salmon, may also be responsible. Regardless of the cause, these wide-spread phenotypic shifts influence fecundity and population abundance, and ultimately may put populations and associated fisheries at risk of decline. PMID:26090990

  16. Deepwater Spawning of Fall Chinook Salmon (Oncorhynchus tshawytscha) Near Ives and Pierce Island of the Columbia River, 2000.

    SciTech Connect

    Mueller, Robert P.

    2001-10-01

    Fall chinook salmon (Oncorhynchus tshawytscha), thought to originate from Bonneville Hatchery, were first noted to be spawning downstream of Bonneville Dam by Washington Department of Fisheries and Wildlife (WDFW) biologists in 1993 (Hymer 1997). Known spawning areas included gravel beds on the Washington side of the river near Hamilton Creek and Ives Island. The size of this population from 1994 to 1996 was estimated at 1,800 to 5,200 fish (Hymer 1997), and 554 fish in 1998 (Van der Naald et al. 1999). These estimates were based on carcass surveys and visual observation of redds by boat near the shoreline. Pacific Northwest National Laboratory (PNNL) conducted underwater video surveys in the fall of 1999 and 2000 to determine the extent of the fall chinook salmon spawning and to estimate the number of redds occurring in deeper water. Estimates of redds occurring in water depths exceeding 2.2 m at 143,000 cubic feet per second (kcfs) were 499 in 1999 (Mueller and Dauble 1999) and 567 redds >2.2 m at 127 kcfs in 2000 (this study). The majority of the redds found were confined near the main river channel adjacent to Pierce Island. Chum salmon (O. keta) also have been documented using the mouth of Hamilton Creek and portions of Hamilton Slough for spawning. The majority of chum salmon were found to spawn in shallow water at the mouth of Hamilton Creek adjacent to Ives Island. Estimates of the natural chum salmon spawning population for 1998 were 226 (Van der Naald et al. 1999). Chum salmon spawning near Ives Island are part of the Columbia River evolutionary significant unit (ESU), and are included in the Endangered Species Act of 1973 (ESA) listing in March 1999. Our main objective of this study was to locate deep water spawning locations of fall chinook salmon in the main Columbia River channel and to collect additional data on physical habitat parameters at spawning sites. The secondary objective was to map any chum salmon redds located in the deep sections of

  17. A synthesis of innovative experiences in population education in Asia and the Pacific.

    PubMed

    1982-07-01

    Several innovative experiences in population education in Asian and Pacific countries have been designed that enhance its effective contribution to the alleviation of population related problems. As a contributor to national development goals, population education programs are used to refocus the entire educational system to hasten and facilitate macro-level development efforts to slow population growth in order to improve the standard of living. Several countries have included the programs in their development plans. Population education has also contributed to the renovation of school curricula at the primary, secondary, and tertiary levels in terms of content and teaching methodologies. 3 approaches are used to integrate population education in existing disciplines in formal education. The subunit approach prepares teaching units which are added to an existing unit in the course syllabus of a subject area. This approach is used in the Philippines, Korea, and Thailand. Infusion expands existing units in the syllabi to include population related ideas. The education content remains the same but relevant new examples are substituted. In the 3rd approach, the curricula of selected subjects are overhauled to allow for the permeation of relevant ideas. Population education has been integrated into several nonformal education programs including literacy and adult education, labor training, and agricultural extension. Several approaches are utilized. Separate courses are developed and used in ongoing programs such as training for field functionaries or out-of-school youth and adults. Infusion is used especially in literacy and rural development programs to demonstrate the relationship between population issues and quality of life. Core learning kit approaches are self-contained, using teaching/learning materials to convey a predetermined set of population education concepts to target audiences with common interests and needs. 6 training schemes have evolved to train

  18. SALMON: A WORLD AND HISTORICAL PERSPECTIVE

    EPA Science Inventory

    The four nations of Salmon World have existed for 10,000 years. Since the end of the last Ice Age, salmon established naturally substantial populations and prospered in four large regions of the earth: (1) the European side of the North Atlantic; (2) the North American side of...

  19. THE FOUR NATIONS OF SALMON WORLD

    EPA Science Inventory

    The four nations of Salmon World have existed for 10,000 years. Since the end of the last Ice Age, salmon established naturally substantial populations and prospered in four large regions of the earth: (1) the European side of the North Atlantic; (2) the North American side of...

  20. Salmon's Laws.

    ERIC Educational Resources Information Center

    Shannon, Thomas A.

    1994-01-01

    Presents Paul Salmon's old-fashioned, common-sense guidelines for success in practical school administration. The maxims advise on problem ownership; the value of selective neglect; the importance of empowerment, enthusiasm, and effective communication; and the need for positive reinforcement, cultivation of support, and good relations with media,…

  1. Population genomics of Pacific lamprey: adaptive variation in a highly dispersive species.

    PubMed

    Hess, Jon E; Campbell, Nathan R; Close, David A; Docker, Margaret F; Narum, Shawn R

    2013-06-01

    Unlike most anadromous fishes that have evolved strict homing behaviour, Pacific lamprey (Entosphenus tridentatus) seem to lack philopatry as evidenced by minimal population structure across the species range. Yet unexplained findings of within-region population genetic heterogeneity coupled with the morphological and behavioural diversity described for the species suggest that adaptive genetic variation underlying fitness traits may be responsible. We employed restriction site-associated DNA sequencing to genotype 4439 quality filtered single nucleotide polymorphism (SNP) loci for 518 individuals collected across a broad geographical area including British Columbia, Washington, Oregon and California. A subset of putatively neutral markers (N = 4068) identified a significant amount of variation among three broad populations: northern British Columbia, Columbia River/southern coast and 'dwarf' adults (F(CT) = 0.02, P ≪ 0.001). Additionally, 162 SNPs were identified as adaptive through outlier tests, and inclusion of these markers revealed a signal of adaptive variation related to geography and life history. The majority of the 162 adaptive SNPs were not independent and formed four groups of linked loci. Analyses with matsam software found that 42 of these outlier SNPs were significantly associated with geography, run timing and dwarf life history, and 27 of these 42 SNPs aligned with known genes or highly conserved genomic regions using the genome browser available for sea lamprey. This study provides both neutral and adaptive context for observed genetic divergence among collections and thus reconciles previous findings of population genetic heterogeneity within a species that displays extensive gene flow.

  2. The spatial scale of genetic subdivision in populations of Ifremeria nautilei, a hydrothermal-vent gastropod from the southwest Pacific

    PubMed Central

    2011-01-01

    Background Deep-sea hydrothermal vents provide patchy, ephemeral habitats for specialized communities of animals that depend on chemoautotrophic primary production. Unlike eastern Pacific hydrothermal vents, where population structure has been studied at large (thousands of kilometres) and small (hundreds of meters) spatial scales, population structure of western Pacific vents has received limited attention. This study addresses the scale at which genetic differentiation occurs among populations of a western Pacific vent-restricted gastropod, Ifremeria nautilei. Results We used mitochondrial and DNA microsatellite markers to infer patterns of gene flow and population subdivision. A nested sampling strategy was employed to compare genetic diversity in discrete patches of Ifremeria nautilei separated by a few meters within a single vent field to distances as great as several thousand kilometres between back-arc basins that encompass the known range of the species. No genetic subdivisions were detected among patches, mounds, or sites within Manus Basin. Although I. nautilei from Lau and North Fiji Basins (~1000 km apart) also exhibited no evidence for genetic subdivision, these populations were genetically distinct from the Manus Basin population. Conclusions An unknown process that restricts contemporary gene flow isolates the Manus Basin population of Ifremeria nautilei from widespread populations that occupy the North Fiji and Lau Basins. A robust understanding of the genetic structure of hydrothermal vent populations at multiple spatial scales defines natural conservation units and can help minimize loss of genetic diversity in situations where human activities are proposed and managed. PMID:22192622

  3. Results and evaluation of a survey to estimate Pacific walrus population size, 2006

    USGS Publications Warehouse

    Speckman, Suzann G.; Chernook, Vladimir I.; Burn, Douglas M.; Udevitz, Mark S.; Kochnev, Anatoly A.; Vasilev, Alexander; Jay, Chadwick V.; Lisovsky, Alexander; Fischbach, Anthony S.; Benter, R. Bradley

    2011-01-01

    In spring 2006, we conducted a collaborative U.S.-Russia survey to estimate abundance of the Pacific walrus (Odobenus rosmarus divergens). The Bering Sea was partitioned into survey blocks, and a systematic random sample of transects within a subset of the blocks was surveyed with airborne thermal scanners using standard strip-transect methodology. Counts of walruses in photographed groups were used to model the relation between thermal signatures and the number of walruses in groups, which was used to estimate the number of walruses in groups that were detected by the scanner but not photographed. We also modeled the probability of thermally detecting various-sized walrus groups to estimate the number of walruses in groups undetected by the scanner. We used data from radio-tagged walruses to adjust on-ice estimates to account for walruses in the water during the survey. The estimated area of available habitat averaged 668,000 km2 and the area of surveyed blocks was 318,204 km2. The number of Pacific walruses within the surveyed area was estimated at 129,000 with 95% confidence limits of 55,000 to 507,000 individuals. This value can be used by managers as a minimum estimate of the total population size.

  4. Integration of Random Forest with population-based outlier analyses provides insight on the genomic basis and evolution of run timing in Chinook salmon (Oncorhynchus tshawytscha).

    PubMed

    Brieuc, Marine S O; Ono, Kotaro; Drinan, Daniel P; Naish, Kerry A

    2015-06-01

    Anadromous Chinook salmon populations vary in the period of river entry at the initiation of adult freshwater migration, facilitating optimal arrival at natal spawning. Run timing is a polygenic trait that shows evidence of rapid parallel evolution in some lineages, signifying a key role for this phenotype in the ecological divergence between populations. Studying the genetic basis of local adaptation in quantitative traits is often impractical in wild populations. Therefore, we used a novel approach, Random Forest, to detect markers linked to run timing across 14 populations from contrasting environments in the Columbia River and Puget Sound, USA. The approach permits detection of loci of small effect on the phenotype. Divergence between populations at these loci was then examined using both principle component analysis and FST outlier analyses, to determine whether shared genetic changes resulted in similar phenotypes across different lineages. Sequencing of 9107 RAD markers in 414 individuals identified 33 predictor loci explaining 79.2% of trait variance. Discriminant analysis of principal components of the predictors revealed both shared and unique evolutionary pathways in the trait across different lineages, characterized by minor allele frequency changes. However, genome mapping of predictor loci also identified positional overlap with two genomic outlier regions, consistent with selection on loci of large effect. Therefore, the results suggest selective sweeps on few loci and minor changes in loci that were detected by this study. Use of a polygenic framework has provided initial insight into how divergence in a trait has occurred in the wild. PMID:25913096

  5. Integration of Random Forest with population-based outlier analyses provides insight on the genomic basis and evolution of run timing in Chinook salmon (Oncorhynchus tshawytscha).

    PubMed

    Brieuc, Marine S O; Ono, Kotaro; Drinan, Daniel P; Naish, Kerry A

    2015-06-01

    Anadromous Chinook salmon populations vary in the period of river entry at the initiation of adult freshwater migration, facilitating optimal arrival at natal spawning. Run timing is a polygenic trait that shows evidence of rapid parallel evolution in some lineages, signifying a key role for this phenotype in the ecological divergence between populations. Studying the genetic basis of local adaptation in quantitative traits is often impractical in wild populations. Therefore, we used a novel approach, Random Forest, to detect markers linked to run timing across 14 populations from contrasting environments in the Columbia River and Puget Sound, USA. The approach permits detection of loci of small effect on the phenotype. Divergence between populations at these loci was then examined using both principle component analysis and FST outlier analyses, to determine whether shared genetic changes resulted in similar phenotypes across different lineages. Sequencing of 9107 RAD markers in 414 individuals identified 33 predictor loci explaining 79.2% of trait variance. Discriminant analysis of principal components of the predictors revealed both shared and unique evolutionary pathways in the trait across different lineages, characterized by minor allele frequency changes. However, genome mapping of predictor loci also identified positional overlap with two genomic outlier regions, consistent with selection on loci of large effect. Therefore, the results suggest selective sweeps on few loci and minor changes in loci that were detected by this study. Use of a polygenic framework has provided initial insight into how divergence in a trait has occurred in the wild.

  6. Large genetic distances among Aedes aegypti populations along the South Pacific coast of Mexico.

    PubMed

    García-Franco, Francisco; Muńoz, Maria De Lourdes; Lozano-Fuentes, Saul; Fernandez-Salas, Ildefonso; Garcia-Rejon, Julian; Beaty, Barry J; Black, William C

    2002-05-01

    A population genetic analysis was conducted among 20 Aedes aegypti collections from 19 cities along the south Pacific coast in the Mexican states of Guerrero, Oaxaca, and Chiapas and in Coatepeque, Guatemala. Genetic variation was scored at 131 random amplified polymorphic DNA loci. The amount of genetic differentiation among collections was approximately 3 times as great as detected among collections in an earlier study in northeastern Mexico. Regression analysis of linear or road distances on linearized F(ST) indicated that collections are genetically isolated by distance. Cluster analysis failed to group collections in geographic proximity, and there was as much genetic variation among collections 60 km apart as there was among all collections (approximately 900-km range). The large genetic differentiation in southern Mexico reflects reduced gene flow among mosquitoes arising in a greater diversity of habitats and altitudes than exists among northeastern collections. It is likely that dispersal via human commerce in the northeast confounds patterns of natural gene flow.

  7. Population genetics of the invasive cryptogenic anemone, Anemonia alicemartinae, along the southeastern Pacific coast

    NASA Astrophysics Data System (ADS)

    Canales-Aguirre, C. B.; Quiñones, A.; Hernández, C. E.; Neill, P. E.; Brante, A.

    2015-08-01

    One of the most important issues in biological invasions is understanding the factors and mechanisms determining the invasion success of non-native species. Theoretical and empirical works have shown that genetic diversity is a determinant of invasion success; thus, studying spatial patterns of genetic diversity, and exploring how biological and physical factors shape this population trait, are fundamental for understanding this phenomenon. Coastal marine ecosystems are one of the most susceptible habitats to invasion given the complex network of maritime transport. In this work we study the cryptogenic anemone, Anemonia alicemartinae, which has rapidly increased its geographical range southward during the last 50 years (approx. 2000 km) along the southeastern Pacific coast. Based on COI mtDNA sequences we evaluated three main hypotheses: a) the genetic diversity of A. alicemartinae decreases according to the direction of invasion (from north to south); b) there is biogeographic-phylogeographic concordance at the 30°S biogeographic break; and c) the demographic history is coherent with a recent geographic expansion. A total of 161 individual samples of A. alicemartinae were collected along the southeastern Pacific coast range of distribution, covering more than 2000 km, including samples along the 30°S biogeographical break. Results showed low genetic diversity (Hd = 0.253; π = 0.08) and a lack of geographic population genetic structure (FST = - 0.009, p-value = 0.656). The highest genetic diversity was observed in Peru (Chero and Mesas) and at localities close to the main Chilean seaports. We did not observe concordance between biogeographic and phylogeographic patterns or isolation by distance. Demographic indices (D = - 2.604, p < 0.001; Fu's = - 26.619, p < 0.001), as well as a star-like configuration of the haplotype network support recent population expansion of this species. Our results, together with historical field observations, support the idea that

  8. Genetic divergence in nuclear genomes between populations of Fagus crenata along the Japan Sea and Pacific sides of Japan.

    PubMed

    Hiraoka, Koichi; Tomaru, Nobuhiro

    2009-05-01

    Genetic diversity and structure in Fagus crenata were studied by analyzing 14 nuclear microsatellite loci in 23 populations distributed throughout the species' range. Although population differentiation was very low (F (ST) = 0.027; R (ST) = 0.041), both neighbor-joining tree and Bayesian clustering analyses provided clear evidence of genetic divergence between populations along the Japan Sea (Japan Sea lineage) and Pacific (Pacific lineage) sides of Japan, indicating that physical barriers to migration and gene flow, notably the mountain ranges separating the populations along the Japan Sea and Pacific sides, have promoted genetic divergence between these populations. The two lineages of the nuclear genome are generally consistent with those of the chloroplast genome detected in a previous study, with several discrepancies between the two genomes. Within-population genetic diversity was generally very high (average H (E) = 0.839), but decreased in a clinal fashion from southwest to northeast, largely among populations of the Japan Sea lineage. This geographical gradient may have resulted from the late-glacial and postglacial recolonization to the northeast, which led to a loss of within-population genetic diversity due to cumulative founder effects. PMID:19238323

  9. Piscine reovirus, but not Jaundice Syndrome, was transmissible to Chinook Salmon, Oncorhynchus tshawytscha (Walbaum), Sockeye Salmon, Oncorhynchus nerka (Walbaum), and Atlantic Salmon, Salmo salar L.

    USGS Publications Warehouse

    Garver, Kyle A.; Marty, Gary D.; Cockburn, Sarah N.; Richard, Jon; Hawley, Laura M.; Müller, Anita; Thompson, Rachel L.; Purcell, Maureen K.; Saksida, Sonja M.

    2016-01-01

    A Jaundice Syndrome occurs sporadically among sea-pen-farmed Chinook Salmon in British Columbia, the westernmost province of Canada. Affected salmon are easily identified by a distinctive yellow discolouration of the abdominal and periorbital regions. Through traditional diagnostics, no bacterial or viral agents were cultured from tissues of jaundiced Chinook Salmon; however, piscine reovirus (PRV) was identified via RT-rPCR in all 10 affected fish sampled. By histopathology, Jaundice Syndrome is an acute to peracute systemic disease, and the time from first clinical signs to death is likely <48 h; renal tubular epithelial cell necrosis is the most consistent lesion. In an infectivity trial, Chinook Salmon, Sockeye Salmon and Atlantic Salmon, intraperitoneally inoculated with a PRV-positive organ homogenate from jaundiced Chinook Salmon, developed no gross or microscopic evidence of jaundice despite persistence of PRV for the 5-month holding period. The results from this study demonstrate that the Jaundice Syndrome was not transmissible by injection of material from infected fish and that PRV was not the sole aetiological factor for the condition. Additionally, these findings showed the Pacific coast strain of PRV, while transmissible, was of low pathogenicity for Atlantic Salmon, Chinook Salmon and Sockeye Salmon.

  10. Piscine reovirus, but not Jaundice Syndrome, was transmissible to Chinook Salmon, Oncorhynchus tshawytscha (Walbaum), Sockeye Salmon, Oncorhynchus nerka (Walbaum), and Atlantic Salmon, Salmo salar L.

    PubMed

    Garver, K A; Marty, G D; Cockburn, S N; Richard, J; Hawley, L M; Müller, A; Thompson, R L; Purcell, M K; Saksida, S

    2016-02-01

    A Jaundice Syndrome occurs sporadically among sea-pen-farmed Chinook Salmon in British Columbia, the westernmost province of Canada. Affected salmon are easily identified by a distinctive yellow discolouration of the abdominal and periorbital regions. Through traditional diagnostics, no bacterial or viral agents were cultured from tissues of jaundiced Chinook Salmon; however, piscine reovirus (PRV) was identified via RT-rPCR in all 10 affected fish sampled. By histopathology, Jaundice Syndrome is an acute to peracute systemic disease, and the time from first clinical signs to death is likely <48 h; renal tubular epithelial cell necrosis is the most consistent lesion. In an infectivity trial, Chinook Salmon, Sockeye Salmon and Atlantic Salmon, intraperitoneally inoculated with a PRV-positive organ homogenate from jaundiced Chinook Salmon, developed no gross or microscopic evidence of jaundice despite persistence of PRV for the 5-month holding period. The results from this study demonstrate that the Jaundice Syndrome was not transmissible by injection of material from infected fish and that PRV was not the sole aetiological factor for the condition. Additionally, these findings showed the Pacific coast strain of PRV, while transmissible, was of low pathogenicity for Atlantic Salmon, Chinook Salmon and Sockeye Salmon. PMID:25630226

  11. Genetic characterization of five hatchery populations of the Pacific Abalone (Haliotis discus hannai) using microsatellite markers.

    PubMed

    An, Hye Suck; Lee, Jang Wook; Kim, Hyun Chul; Myeong, Jeong-In

    2011-01-01

    The Pacific abalone, Haliotis discus hannai, is a popular food in Eastern Asia. Aquacultural production of this species has increased because of recent resource declines, the growing consumption, and ongoing government-operated stock release programs. Therefore, the genetic characterization of hatchery populations is necessary to maintain the genetic diversity of this species and to develop more effective aquaculture practices. We analyzed the genetic structures of five cultured populations in Korea using six microsatellite markers. The number of alleles per locus ranged from 15 to 64, with an average of 23.5. The mean observed and expected heterozygosities were 0.797 and 0.904, respectively. The inbreeding coefficient F(IS) ranged from 0.054 to 0.184 (mean F(IS) = 0.121 ± 0.056). The genetic differentiation across all populations was low but significant (overall F(ST) = 0.009, P < 0.01). Pairwise multilocus F(ST) tests, estimates of genetic distance, and phylogenetic and principal component analyses did not show a consistent relationship between geographic and genetic distances. These results could reflect extensive aquaculture, the exchange of breeds and eggs between hatcheries and/or genetic drift due to intensive breeding practices. Thus, for optimal resource management, the genetic variation of hatchery stocks should be monitored and inbreeding controlled within the abalone stocks that are being released every year. This genetic information will be useful for the management of both H. discus hannai fisheries and the aquaculture industry.

  12. The Asian-American and Pacific Islander population and the American Cancer Society initiative.

    PubMed

    Vance, Ralph

    2005-12-15

    The American Cancer Society (ACS) Nationwide Asian-American/Pacific Islander (AAPI) Initiative is a continuing collaboration between the ACS and other organizations and community groups. With a view to incorporating access to quality treatment as an over-arching principal, the objectives of the AAPI Initiative are to provide strategic oversight to the ACS for outreach to AAPI populations and to develop a nationwide plan for the purpose of making ACS programs and services available to these populations. After a series of meetings in 2002, including a joint meeting between the Asian American Network for Cancer Awareness, Research, and Training (AANCART) and the ACS, the first ACS Nationwide AAPI Council meeting was held in early 2003. The goals and objectives of this initiative are 1) to develop a plan for delivery of ACS programs and services to the AAPI population, 2) to develop a program for collaboration with organizations that can help the ACS reach its objectives, 3) to develop an advocacy program that enables the ACS to reach its objectives, and 4) to develop an income-development program to both reach and maintain these objectives. The ACS-AANCART collaboration is a great example of the type of collaboration that will make not only the ACS but also the cancer community as a whole successful in eradicating cancer as a major public health problem.

  13. Seasonal abundance of the microplankton population in the North Pacific central gyre

    NASA Astrophysics Data System (ADS)

    Beers, John R.; Reid, Freda M. H.; Stewart, Gene L.

    1982-02-01

    Population structure as numerical and biomas abundance was determined for the microplankton (˜ to 200 μm organisms) sampled throughout and just below the euphotic zone at five times of year other than fall in the North Pacific central gyre around 28°N, 155°W. Average total microplankton carbon of all strata varied by twofold or less over the cruises, conforming to the hypothesis of low heterogeneity of biomass in central oceanic gyral populations. For example, mean euphotic zone abundance ranged from 5.9 μg Cl -1 (late winter) to 10.5 μg Cl -1 (spring), averaging 7.9 μg Cl -1. Its variability and that of stations within cruises were similar. Microplankton did not show a maximum correlated with the chlorophyll α maximum seen near the base o