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Abstract Climate change is altering the distribution and abundance of marine species, especially in Arctic and sub‐Arctic regions. In the eastern Bering Sea, home of the world's largest run of sockeye salmon (Oncorhynchus nerka), juvenile sockeye salmon abundance has increased and their migration path shifted north with warming, 2002–2018. The reasons for these changes are poorly understood. For these sockeye salmon, we quantify environmental and biological covariate effects within spatio‐temporal species distribution models. Spatio‐temporally, with respect to juvenile sockeye salmon densities: (1) sea surface temperature had a nonlinear effect, (2) large copepod, Calanus, a minor prey item, had no effect, (3) age‐0 pollock (Gadus chalcogrammus), a major prey item during warm years, had a positive linear effect, and (4) juvenile pink salmon (O. gorbuscha) had a positive linear effect. Temporally, annual biomass of juvenile sockeye salmon was nonlinearly related to sea temperature and positively related to age‐0 pollock and juvenile pink salmon abundance. Results indicate that sockeye salmon distributed with and increased in abundance with increases in prey, and reached a threshold for optimal temperatures in the eastern Bering Sea. Changes in population dynamics and distribution of sockeye salmon in response to environmental variability have potential implications for projecting specific future food securities and management of fisheries in Arctic waters.

Abstract Alternative life‐history tactics are predicted to affect within‐population genetic processes but have received little attention. For example, the impact of precocious males on effective population size (Ne) has not been quantified directly in Pacific salmon Oncorhynchus spp., even though they can make up a large percentage of the total male spawners. We investigated the contribution of precocial males (“jacks”) to Ne in a naturally spawning population of Coho Salmon O. kisutch from the Auke Creek watershed in Juneau, Alaska. Mature adults that returned from 2009 to 2019 (~8000 individuals) were genotyped at 259 single‐nucleotide polymorphism (SNP) loci for parentage analysis. We used demographic and genetic methods to estimate the effective number of breeders per year (Nb). Jack contribution to Nb was assessed by comparing values of Nb calculated with and without jacks and their offspring. Over a range of Nb values (108–406), the average jack contribution to Nb from 2009 to 2015 was 12.9% (SE = 3.8%). Jacks consistently made up over 20% of the total male spawners. The presence of jacks did not seem to influence Nb/N. The linkage disequilibrium Ne estimate was lower than the demographic estimate, possibly due to immigration effects on population genetic processes: based on external marks and parentage data, we estimated that immigrant spawners produced 4.5% of all returning offspring. Our results demonstrate that jacks can influence Nb and Ne and can make a substantial contribution to population dynamics and conservation of threatened stocks.

Abstract As Pacific salmon (Oncorhynchus spp.) decline across much of their range, it is imperative to further develop minimally invasive tools to quantify population abundance. One such advancement, trans‐generational genetic mark–recapture (tGMR), uses parentage analysis to estimate the size of wild populations. Our study examined the precision and accuracy of tGMR through a comparison to a traditional mark–recapture estimate for Chilkat River Chinook salmon (O. tshawytscha) in Southeast Alaska. We examined how adult sampling location and timing impact tGMR by comparing estimates derived using samples collected in the lower river mainstem to those using samples obtained in upriver spawning tributaries. Results indicated that tGMR estimates using a representative sample of mainstem adults were most concordant with, and 3% more precise than, the traditional mark–recapture estimate for this stock. Importantly, the timing and location of adult sampling were found to impact abundance estimates, depending on what proportion of the population dies or moves to unsampled areas between downriver and upriver sampling events. Additionally, we identified potential sources of bias in tGMR arising from violations of key assumptions using a novel individual‐based modeling framework, parameterized with empirical values from the Chilkat River. Simulations demonstrated that increased reproductive success and sampling selectivity of older, larger individuals, introduced negative bias into tGMR estimates. Our individual‐based model offers a customizable and accessible method to identify and quantify these biases in tGMR applications (https://github.com/swrosenbaum/tGMR_simulations). We underscore the critical role of system‐specific sampling design considerations in ensuring the precision and accuracy of tGMR projects. This study validates tGMR as a potentially useful tool for improved population enumeration in semelparous species.

Abstract Recent empirical studies have quantified correlation between survival and recovery by estimating these parameters as correlated random effects with hierarchical Bayesian multivariate models fit to tag‐recovery data. In these applications, increasingly negative correlation between survival and recovery has been interpreted as evidence for increasingly additive harvest mortality. The power of these hierarchal models to detect nonzero correlations has rarely been evaluated, and these few studies have not focused on tag‐recovery data, which is a common data type. We assessed the power of multivariate hierarchical models to detect negative correlation between annual survival and recovery. Using three priors for multivariate normal distributions, we fit hierarchical effects models to a mallard (Anas platyrhychos) tag‐recovery data set and to simulated data with sample sizes corresponding to different levels of monitoring intensity. We also demonstrate more robust summary statistics for tag‐recovery data sets than total individuals tagged. Different priors led to substantially different estimates of correlation from the mallard data. Our power analysis of simulated data indicated most prior distribution and sample size combinations could not estimate strongly negative correlation with useful precision or accuracy. Many correlation estimates spanned the available parameter space (−1,1) and underestimated the magnitude of negative correlation. Only one prior combined with our most intensive monitoring scenario provided reliable results. Underestimating the magnitude of correlation coincided with overestimating the variability of annual survival, but not annual recovery. The inadequacy of prior distributions and sample size combinations previously assumed adequate for obtaining robust inference from tag‐recovery data represents a concern in the application of Bayesian hierarchical models to tag‐recovery data. Our analysis approach provides a means for examining prior influence and sample size on hierarchical models fit to capture–recapture data while emphasizing transferability of results between empirical and simulation studies.

Disentangling the influences of climate change from other stressors affecting the population dynamics of aquatic species is particularly pressing for northern latitude ecosystems, where climate‐driven warming is occurring faster than the global average. Chinook salmon (Oncorhynchus tshawytscha) in the Yukon‐Kuskokwim (YK) region occupy the northern extent of their species' range and are experiencing prolonged declines in abundance resulting in fisheries closures and impacts to the well‐being of Indigenous people and local communities. These declines have been associated with physical (e.g., temperature, streamflow) and biological (e.g., body size, competition) conditions, but uncertainty remains about the relative influence of these drivers on productivity across populations and how salmon–environment relationships vary across watersheds. To fill these knowledge gaps, we estimated the effects of marine and freshwater environmental indicators, body size, and indices of competition, on the productivity (adult returns‐per‐spawner) of 26 Chinook salmon populations in the YK region using a Bayesian hierarchical stock‐recruitment model. Across most populations, productivity declined with smaller spawner body size and sea surface temperatures that were colder in the winter and warmer in the summer during the first year at sea. Decreased productivity was also associated with above average fall maximum daily streamflow, increased sea ice cover prior to juvenile outmigration, and abundance of marine competitors, but the strength of these effects varied among populations. Maximum daily stream temperature during spawning migration had a nonlinear relationship with productivity, with reduced productivity in years when temperatures exceeded thresholds in main stem rivers. These results demonstrate for the first time that well‐documented declines in body size of YK Chinook salmon were associated with declining population productivity, while taking climate into account. [ABSTRACT FROM AUTHOR]

Understanding how ecosystem change influences fishery resources through trophic pathways is a key tenet of ecosystem‐based fishery management. System models (SM), which use numerical modeling to describe physical and biological processes, can advance inclusion of ecosystem and prey information in fisheries management; however, incorporating SMs in management requires evaluation against empirical data. The Bering Ecosystem Study Nutrient‐Phytoplankton‐Zooplankton (BESTNPZ) model is an SM (originally created by the Bering Ecosystem Study, which initiated in 2006 and was expanded by Kearney et al.) includes zooplankton biomass hindcasts for the Bering Sea. In the Bering Sea, zooplankton are an important prey item for fishery species, yet the zooplankton component of this SM has not been validated against empirical data. We compared empirical zooplankton data to BESTNPZ hindcast estimates for three zooplankton functional groups and found that the two sources of information are on different absolute scales. We found high correlation between relative seasonal biomass trends estimated by BESTNPZ and empirical data for large off‐shelf copepods (Neocalanus spp.) and low correlations for large on‐shelf copepods and small copepods (Calanus spp. and Pseudocalanus spp., respectively). To address these discrepancies, we constructed hybrid species distribution models (H‐SDM), which predict zooplankton biomass using the BESTNPZ hindcast and environmental covariates. We found that H‐SDMs offered marginal improvements over correlative species distribution models (C‐SDMs) relying solely on empirical data for spatial extrapolation and little improvement for most functional groups when forecasting short‐term temporal zooplankton biomass trends. Overall, we suggest that interpretation of current BESTNPZ hindcasts should be tempered by our understanding of key mismatches in absolute scale, seasonality, and annual indices between BESTNPZ and empirical data. [ABSTRACT FROM AUTHOR]

Pacific salmon (Oncorhynchus spp.) spend much of their life near the ocean surface where climatic and oceanographic conditions affect their habitat and survival. Despite decades of study, critical knowledge gaps persist regarding their ecology and distributions. Consequently, it has been difficult to assess how environmental conditions influence the high‐seas distribution and habitat use of these culturally and socioeconomically important fishes, presenting challenges to fisheries managers trying to evaluate how climate change and fishing activities may impact salmon populations. We used a recently compiled, comprehensive database of historical coastal and high‐seas salmon survey data (1953–2022) in the North Pacific to fit species distribution models that (1) characterize the marine spatial distribution of six species of Oncorhynchus, (2) evaluate species‐specific temperature preferences, and (3) investigate how species' temperature preferences influence distribution. Sea surface temperature, along with seasonal migrations associated with spawning and feeding, significantly affects the distribution of all species, where the warm limits of estimated preferred thermal ranges were more similar than the cold limits. Furthermore, the distributions of some species appear more responsive to temperature than others and recently observed warm conditions have likely impacted realized ranges. These models have expanded our understanding of salmon ocean distributions and thermal niches by providing a unique window into this often unobserved but important part of the life cycle. They also serve as a baseline for future investigations into the mechanisms influencing salmon spatial ecology, responses to climate change, and vulnerability to harvest across the North Pacific. [ABSTRACT FROM AUTHOR]

Rapid climate change is altering Arctic ecosystems at unprecedented rates. These changes in the physical environment may open new corridors for species range expansions, with substantial implications for subsistence‐dependent communities and sensitive ecosystems. Over the past 20 years, rising incidental harvest of Pacific salmon by subsistence fishers has been monitored across a widening range spanning multiple land claim jurisdictions in Arctic Canada. In this study, we connect Indigenous and scientific knowledges to explore potential oceanographic mechanisms facilitating this ongoing northward expansion of Pacific salmon into the western Canadian Arctic. A regression analysis was used to reveal and characterize a two‐part mechanism related to thermal and sea‐ice conditions in the Chukchi and Beaufort seas that explains nearly all of the variation in the relative abundance of salmon observed within this region. The results indicate that warmer late‐spring temperatures in a Chukchi Sea watch‐zone and persistent, suitable summer thermal conditions in a Beaufort Sea watch‐zone together create a range‐expansion corridor and are associated with higher salmon occurrences in subsistence harvests. Furthermore, there is a body of knowledge to suggest that these conditions, and consequently the presence and abundance of Pacific salmon, will become more persistent in the coming decades. Our collaborative approach positions us to document, explore, and explain mechanisms driving changes in fish biodiversity that have the potential to, or are already affecting, Indigenous rights‐holders in a rapidly warming Arctic. [ABSTRACT FROM AUTHOR]

Climate change is altering the distribution and abundance of marine species, especially in Arctic and sub‐Arctic regions. In the eastern Bering Sea, home of the world's largest run of sockeye salmon (Oncorhynchus nerka), juvenile sockeye salmon abundance has increased and their migration path shifted north with warming, 2002–2018. The reasons for these changes are poorly understood. For these sockeye salmon, we quantify environmental and biological covariate effects within spatio‐temporal species distribution models. Spatio‐temporally, with respect to juvenile sockeye salmon densities: (1) sea surface temperature had a nonlinear effect, (2) large copepod, Calanus, a minor prey item, had no effect, (3) age‐0 pollock (Gadus chalcogrammus), a major prey item during warm years, had a positive linear effect, and (4) juvenile pink salmon (O. gorbuscha) had a positive linear effect. Temporally, annual biomass of juvenile sockeye salmon was nonlinearly related to sea temperature and positively related to age‐0 pollock and juvenile pink salmon abundance. Results indicate that sockeye salmon distributed with and increased in abundance with increases in prey, and reached a threshold for optimal temperatures in the eastern Bering Sea. Changes in population dynamics and distribution of sockeye salmon in response to environmental variability have potential implications for projecting specific future food securities and management of fisheries in Arctic waters. [ABSTRACT FROM AUTHOR]

Chinook salmon (Oncorhynchus tshawytscha) populations have experienced widespread declines in abundance and abrupt shifts toward younger and smaller adults returning to spawn in rivers. The causal agents underpinning these shifts are largely unknown. Here we investigate the potential role of late-stage marine mortality, defined as occurring after the first winter at sea, in driving this species' changing age structure. Simulations using a stage-based life cycle model that included additional mortality during after the first winter at sea better reflected observed changes in the age structure of a well-studied and representative population of Chinook salmon from the Yukon River drainage, compared with a model estimating environmentally-driven variation in age-specific survival alone. Although the specific agents of late-stage mortality are not known, our finding is consistent with work reporting predation by salmon sharks (Lamna ditropis) and marine mammals including killer whales (Orcinus orca). Taken as a whole, this work suggests that Pacific salmon mortality after the first winter at sea is likely to be higher than previously thought and highlights the need to investigate selective sources of mortality, such as predation, as major contributors to rapidly changing age structure of spawning adult Chinook salmon.

We tested the hypothesis that ocean temperature effects on productivity for northeast Pacific pink (Oncorhynchus gorbuscha), sockeye (Oncorhynchus nerka), and chum salmon (Oncorhynchus keta) changed after 1988-1989, coincident with a decline in Aleutian Low variance. Nonstationary temperature effects were tested with three different analytical methods (correlation, mixed-effects models, and variable coefficient generalized additive models) applied to spawner-recruit time series from 86 wild runs between Puget Sound and the northern Bering Sea. All three methods supported the hypothesis, with evidence for change in temperature effects that was strongest in the Gulf of Alaska, British Columbia, and Washington and weakest in the Bering Sea. Productivity for all three species showed generally positive responses to ocean temperature in Alaska before 1988-1989, but generally neutral responses after 1988-1989. British Columbia and Washington salmon showed either neutral responses to temperature (pink), negative responses that weakened after 1988-1989 (sockeye), or a switch from neutral to negative responses (chum). We conclude that the inverse response of Alaskan and more southern salmon populations to temperature variability is a time-dependent phenomenon. Nous avons teste l'hypothese selon laquelle les effets de la temperature de l'ocean sur la productivite des saumons roses (Oncorhynchus gorbuscha), sockeye (Oncorhynchus nerka) et keta (Oncorhynchus keta) du nord-est de l'ocean Pacifique ont change apres 1988-1989, coincidant avec une diminution de la variance de la depression des Aleoutiennes. La presence d'effets non stationnaires de la temperature a ete verifiee par trois methodes analytiques differentes (correlation, modeles a effets mixtes et modeles additifs generalises a coefficients variables) appliquees a des series chronologiques geniteurs-recrues pour 86 migrations de saumons sauvages du Puget Sound a la mer de Behring septentrionale. Les trois methodes appuient l'hypothese, les indices de variations des effets de la temperature etant les plus importants pour le golfe d'Alaska, la Colombie-Britannique et l'Etat de Washington, et les plus faibles pour la mer de Behring. La productivite des trois especes presentait des reactions generalement positives a la temperature de l'ocean en Alaska avant 1988-1989, mais des reactions generalement neutres par la suite. Les saumons de la Colombie-Britannique et l'Etat de Washington presentaient des reactions a la temperature soit neutres (roses), negatives et diminuant apres 1988-1989 (sockeye) ou une transition de reactions neutres a negatives (keta). Nous concluons que les reactions inverses des populations de l'Alaska et des populations plus au sud a la variabilite de la temperature constituent un phenomene dependant du temps. [Traduit par la Redaction], Introduction The Pacific Decadal Oscillation (PDO) was first recognized in relation to inverse production regimes between Pacific salmon (Onchorynchus spp.) in Alaska and more southern areas (Mantua et al. 1997; [...]

Bristol Bay, Alaska, is home to the largest sockeye salmon (Oncorhynchus nerka) fishery in the world, harvesting an average of 25 million fish with an ex-vessel value exceeding US$100 million annually. Daily fishing effort is adaptively managed to achieve stock-specific escapement goals. Traditional methods for defining these goals relied on stock-recruitment analysis; however, this approach often ignores three fundamental sources of uncertainty: estimation error, implementation uncertainty, and time-varying recruitment dynamics. To compare escapement goal alternatives, we conducted a management strategy evaluation that simulated time-varying recruitment across production regimes and replicated the daily in-season management process. Results indicate (i) implementation uncertainty can be reasonably approximated with simple rules reflecting fishery managers' daily decision process; (ii) despite implementation uncertainty, escapement goals are likely to be realized or exceeded, on average; and (iii) management strategies targeting escapement levels estimated by traditional methods to produce maximum sustainable yield may result in lower catch and greater variability in fishing opportunity compared with a strategy with defining high and low escapement goals that are targeted depending on assessed run size, which may maximize future catch while reducing the frequency of extremely low harvests. La baie de Bristol, en Alaska, est le lieu de la plus importante peche au saumon sockeye (Oncorhynchus nerka) du monde, avec une production annuelle moyenne de 25 millions de poissons d'une valeur au debarquement de plus de US$100 millions. L'effort de peche journalier est gere de maniere adaptative pour permettre l'atteinte d'objectifs d'echappement propres au stock. Si les methodes traditionnelles d'etablissement de ces objectifs reposent sur l'analyse du recrutement au stock, cette approche ne tient pas compte, dans bien des cas, de trois sources fondamentales d'incertitude, a savoir l'erreur d'estimation, l'incertitude associee a la mise en reuvre et la dynamique de recrutement variable dans le temps. Afin de comparer differents objectifs d'echappement, nous avons realise une evaluation des strategies de gestion qui simule le recrutement variable dans le temps pour differents regimes de production et reproduit le processus de gestion journaliere durant la saison. Les resultats indiquent que (i) de simples regles refletant le processus decisionnel journalier des gestionnaires de la peche peuvent produire une approximation raisonnable de l'incertitude associee a la mise en reuvre, (ii) malgre l'incertitude associee a la mise en reuvre, les objectifs d'echappement sont susceptibles d'etre atteints ou depasses en moyenne et (iii) des strategies de gestion qui visent des niveaux d'echappement estimes par des methodes traditionnelles pour produire le rendement equilibre maximal peuvent se traduire par des prises plus faibles et une plus grande variabilite des possibilites de peche qu'une strategie qui comprend des objectifs d'echappement eleves et faibles utilises tour a tour selon l'effectif de la montaison evalue, ce qui pourrait maximiser les prises futures tout en reduisant la frequence de productions extremement faibles. [Traduit par la Redaction], Introduction Fisheries management can be made more effective through systematic analysis of management alternatives, where the likelihood and relative risk of potential outcomes are quantified while accounting for both biological [...]

We develop an economically sophisticated management strategy evaluation for four sockeye salmon (Onchorhynchus nerka) fishing districts in Bristol Bay, Alaska, to evaluate whether proposed increases in escapement goals--the number of fish allowed up each river to spawn--could improve fishery outcomes for the industry and the region. Higher escapements increase average runs toward biological maximum sustainable yield, but this is driven by infrequent years of very abundant runs. Our economic model shows processors do not add capacity in response to infrequent abundant runs. Therefore, interannual variance in district-specific catch increases because years with little or no fishing become more frequent to meet higher escapement in low-run years, but industry cannot capture greater value in the high-run years. In abundant runs, processors shift available labor to focus on high-volume, lower-margin products; in very abundant years, insufficient processing capacity allows additional fish to escape. Mobile driftnet vessels that can move to rivers experiencing high runs each year benefit, but district specialists in the small boat and set-net fleets are more vulnerable to years with little or no catch.Nous developpons une evaluation de strategies de gestion economiquement complexes pour quatre districts de peche au saumon rouge (Onchorhynchus nerka) dans la baie de Bristol (Alaska) pour determiner si des augmentations proposees des objectifs d'echappement, soit le nombre de poissons qui peuvent remonter chaque cours d'eau pour frayer, pourraient ameliorer les resultats des peches pour l'industrie et la region. Un plus grand echappement accroit les migrations moyennes qui contribuent au rendement equilibre maximal biologique, mais cela est principalement le fait d'annees peu frequentes de migrations tres abondantes. Notre modele economique montre que les transformateurs ne rehaussent pas leurs capacites en reponse a des migrations abondantes peu frequentes. La variance interannuelle des prises par district augmente donc parce que les annees ou il y a peu ou pas de peche deviennent plus frequentes pour respecter les objectifs d'echappement plus eleves durant les annees de faible migration, mais l'industrie ne peut recuperer une plus-value accrue durant les annees de fortes migrations. Quand les migrations sont abondantes, les transformateurs reaffectent la main-d'reuvre disponible a des produits a grand volume, mais a faible marge beneficiaire, alors que quand les migrations sont tres abondantes, l'insuffisance de la capacite de transformation permet l'echappement d'un plus grand nombre de poissons que prevu. Les navires mobiles a filets derivants qui peuvent se deplacer vers les cours d'eau a migrations abondantes chaque annee en beneficient, mais les pecheurs qui se specialisent dans un district donne dans les flottes de petits bateaux et a filets fixes sont plus vulnerables durant les annees de prises faibles ou nulles. [Traduit par la Redaction], IntroductionThe sockeye salmon (Onchorhynchus nerka) fishery in Bristol Bay, Alaska, illustrates how economic and biological objectives can lead to different harvest policy recommendations. Despite its decades-long biological success, the salmon [...]

Abstract Background Respiratory alarm monitoring and rapid response team alerts on hospital general floors are based on detection of simple numeric threshold breaches. Although some uncontrolled observation trials in select patient populations have been encouraging, randomized controlled trials suggest that this simplistic approach may not reduce the unexpected death rate in this complex environment. The purpose of this review is to examine the history and scientific basis for threshold alarms and to compare thresholds with the actual pathophysiologic patterns of evolving death which must be timely detected. Methods The Pubmed database was searched for articles relating to methods for triggering rapid response teams and respiratory alarms and these were contrasted with the fundamental timed pathophysiologic patterns of death which evolve due to sepsis, congestive heart failure, pulmonary embolism, hypoventilation, narcotic overdose, and sleep apnea. Results In contrast to the simplicity of the numeric threshold breach method of generating alerts, the actual patterns of evolving death are complex and do not share common features until near death. On hospital general floors, unexpected clinical instability leading to death often progresses along three distinct patterns which can be designated as Types I, II and III. Type I is a pattern comprised of hyperventilation compensated respiratory failure typical of congestive heart failure and sepsis. Here, early hyperventilation and respiratory alkalosis can conceal the onset of instability. Type II is the pattern of classic CO2 narcosis. Type III occurs only during sleep and is a pattern of ventilation and SPO2 cycling caused by instability of ventilation and/or upper airway control followed by precipitous and fatal oxygen desaturation if arousal failure is induced by narcotics and/or sedation. Conclusion The traditional threshold breach method of detecting instability on hospital wards was not scientifically derived; explaining the failure of threshold based monitoring and rapid response team activation in randomized trials. Furthermore, the thresholds themselves are arbitrary and capricious. There are three common fundamental pathophysiologic patterns of unexpected hospital death. These patterns are too complex for early detection by any unifying numeric threshold. New methods and technologies which detect and identify the actual patterns of evolving death should be investigated.

Abstract Habitat alteration and species exploitation are fundamental issues in conservation, yet their interacting effects on food webs are rarely considered. We used a foraging model based on the Wood River basin (Alaska, USA) to explore how watershed development and commercial fisheries affect energy flow from sockeye salmon to brown bears. We found that, where salmon are abundant, fisheries can harvest large fractions of runs without substantially reducing bear consumption of salmon, but that watershed development could strongly reduce bear consumption if it shortens the duration of foraging opportunities by reducing population‐level variation in salmon spawn timing. Habitats with the lowest resource abundance (small streams) were particularly profitable for bear foraging because they offer salmon at unique times of the season. This result challenges environmental impact assessments that assume ecological effects respond solely to changes in resource abundance.

Understanding population-specific spawner-recruit relationships is necessary for sustainable salmon management. Where multiple populations are harvested together, run reconstruction methods partition mixed-stock catches and allocate recruits back to their populations of origin. Traditional run reconstruction methods often use age composition data to inform catch partitioning. However age-only methods do not account for stock-specific differences in the availability of fish to harvest within fishing areas or the incidental harvest of nontarget stocks in nearby fishing areas. Advances in molecular genetic techniques permit genetic stock identification (GSI) of both contemporary and historical catch samples. We present a statistical model for salmon run reconstruction that utilizes both age composition and GSI data to estimate differences in the availability of stocks within, and interception rates among, terminal fisheries. When applied to the commercial sockeye salmon (Oncorhynchus nerka) fishery in Bristol Bay, Alaska, new estimates of population productivity differed from those generated using previous age-only methods by 0.1%-155.1%, with stock-specific mean absolute percent differences of 9.7%-38.7% across years, underscoring the value of genetic data for run reconstruction. With more accurate run reconstruction methods, spawner-recruit relationships can be identified more precisely, thus providing more accurate management targets for salmon fisheries. Une comprehension des relations geniteurs-recrues propres a la population est necessaire a une gestion durable des saumons. La ou plusieurs populations sont exploitees ensemble, des methodes de reconstitution des montaisons repartissent les prises de stocks mixtes et affectent les recrues a leurs populations d'origine. Les methodes traditionnelles de reconstitution de montaisons emploient souvent des donnees de composition par age pour guider la repartition des prises. Cependant, les methodes reposant seulement sur l'age ne rendent pas compte des differences propres au stock du nombre de poissons disponibles pour exploitation dans les zones de peche ou des prises accessoires de stocks non cibles dans les zones de peche environnantes. Des avancees dans les techniques de genetique moleculaire permettent l'identification genetique au stock (IGS) d'echantillons de prises tant actuelles que passees. Nous presentons un modele statistique pour la reconstitution de montaisons de saumons qui utilise la composition par age et des donnees d'IGS pour estimer les differences de disponibilite de stocks dans les peches terminales et les taux d'interception entre ces dernieres. Appliquees a la peche commerciale au saumon sockeye (Oncorhynchus nerka) dans la baie de Bristol, en Alaska, les nouvelles estimations de la productivite des populations divergent de 0,1 % a 155,1 % des estimations produites par des methodes anterieures ne reposant que sur l'age, les differences absolues moyennes pour des stocks donnes allant de 9,7 % a 38,7 % selon l'annee, ce qui souligne la valeur des donnees genetiques pour la reconstitution de montaisons. Des methodes de reconstitution de montaisons plus exactes permettent une definition plus precise des relations geniteurs-recrues, produisant ainsi des cibles de gestion plus exactes pour les peches au saumon. [Traduit par la Redaction], Introduction Successful management of commercially exploited species depends on an accurate understanding of how catch and harvest policy influences abundance over time. Management of fish resources to achieve maximum sustainable [...]