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In an era of global change, historical natural history data can improve our understanding of ecological phenomena, particularly when evaluated with contemporary Indigenous and place‐based knowledge. The Yáláƛi (Goose Island) Archipelago is a group of islands in Heiltsuk (Haíɫzaqv) territory on the Central Coast of British Columbia, Canada. Not only has this region been important to the Heiltsuk for millennia but also it is both a federally and internationally recognized important bird area. In this study, we compare data collected by Charles J. Guiguet, a biologist who documented bird communities at Yáláƛi in the summer of 1948, to three different contemporary surveys and to citizen‐science data. We find that the relative abundances of forest bird species (i.e., birds that use the terrestrial island ecosystems) in 1948 differed to those observed in systematic surveys in 2011. While Orange‐crowned Warblers, Dark‐eyed Juncos, and Red Crossbills comprised 55% of detections by Guiguet in 1948, the three most abundant species in 2011 were Bald Eagles, Varied Thrushes, and Pacific Wrens, and these accounted for only 25% of detections. Although we could not make a quantitative comparison, we provide summaries of each species observed in surveys or reported on eBird. We also incorporate Heiltsuk place‐based knowledge to enrich our discussion of the variability in bird communities over time, from how changes in mammal communities and human use may have shaped vegetation dynamics to how large‐scale natural phenomena impacted topography. To understand which birds are present and how their communities are changing over time, we recommend continued monitoring of the bird communities at Yáláƛi. [ABSTRACT FROM AUTHOR]

Foraging success can be mediated by parasites, but this is poorly understood for marine fish whose aggregations and patchy prey fields create conditions for intense intraspecific competition. We evaluated whether sea louse infection is associated with decreased stomach fullness of wild juvenile sockeye salmon (Oncorhynchus nerka) in Johnstone Strait, British Columbia, during their marine migration from the Fraser River. Caligus clemensi comprised 98.6% of the pre-adult and adult lice and 86.5% of the copepodites (freshly attached juvenile lice); the rest were Lepeophtheirus salmonis. We found that infection status was an important predictor of relative stomach fullness for juvenile sockeye (wet stomach content mass divided by body mass), as indicated by mixed-effects model selection, and that highly infected fish had 17% [+ or -] 8% lower relative stomach fullness than did lightly infected fish. This louse-associated reduction in relative stomach fullness occurs as the juvenile sockeye migrate through a food-limited environment and, presumably, elevated competition. Given that early marine growth for juvenile salmon is often a predictor of survival, our results highlight the importance of understanding sublethal effects of parasites on salmonids and possibly other fish species. Les parasites peuvent moduler le succes d'approvisionnement, mais ce phenomene n'est pas bien compris en ce qui concerne les poissons marins, dont les groupements et la repartition parcellaire des proies creent des conditions favorables a une concurrence intraspecifique intense. Nous avons verifie si les infections aux poux du poisson sont associees a la plenitude stomacale des saumons rouges (Oncorhynchus nerka) juveniles sauvages dans le detroit de Johnstone (Colombie-Britannique) durant leur migration vers la mer a partir du fleuve Fraser. Caligus clemensi represente 98,6% des poux du poisson preadultes et adultes et 86,5% des copepodites (individus recemment fixes), alors que Lepeophtheirus salmonis constitue le reste. Nous avons constate que l'etat d'infection est un important predicteur de la plenitude stomacale relative pour les saumons rouges juveniles (masse humide du contenu stomacal divisee par la masse corporelle), comme l'indique la selection de modeles a effets mixtes, et que la plenitude stomacale relative de poissons fortement infectes est de 17%[+ or -]8% inferieure a celle des poissons peu infectes. Cette reduction de la plenitude stomacale relative associee aux poux se produit au moment ou les jeunes saumons rouges en migration passent par un milieu ou la nourriture est restreinte et ou la concurrence est probablement forte. Comme la croissance precoce en mer des saumons juveniles est souvent une variable predictive de la survie, nos resultats soulignent l'importance d'une bonne comprehension des effets subletaux des parasites sur les salmonides et possiblement d'autres especes de poissons. [Traduit par la Redaction], Introduction Foraging success is tightly linked to growth and survival of individuals, both of which are predictors of fitness and population dynamics (Crombie 1947; Sutherland 1996). Fish frequently experience patchy [...]

Salmon provide a key source of marine-derived nutrients to aquatic and surrounding terrestrial habitats in coastal areas of the North Pacific. Bears are a major predator of salmon and provide an important pathway for carcass transfer to riparian zones. We studied selective consumption of salmon (Oncorhynchus keta and Oncorhynchus gorbuscha) by bears (Ursus arctos and Ursus americanus) on 12 streams on the central coast of British Columbia, Canada. We predicted that bears would select more energy-rich parts, and eat less of each fish (i.e., selective consumption), in streams with more prey and simpler habitat (i.e., streams that facilitate salmon capture). Bears were 12% more likely to consume fish selectively in narrow, shallow streams with less pool volume, where salmon are easier to catch, than in deep, wide streams. However, bears were also 21% more likely to selectively consume fish in streams with more wood obstacles and undercut banks, where hunting was predicted to be more difficult. This suggests that stream characteristics can have significant indirect effects on riparian nutrient subsidies to ecosystems through selective feeding by bears. Les saumons constituent une importante source de nutriments d'origine marine pour les habitats aquatiques et terrestres avoisinants dans les regions littorales du Pacifique Nord. Les ours sont un des principaux predateurs des saumons et constituent une importante voie pour le transfert de carcasses aux zones riveraines. Nous avons etudie la consommation selective de saumons (Oncorhynchus keta et Oncothynchus gorbuscha) par les ours (Ursus arctos et Ursus americanus) dans 12 cours d'eau du littoral central de la Colombie-Britannique (Canada). Nous avions predit que les ours selectionneraient les parties plus riches en energie et mangeraient moins de chaque poisson (c.-a-d. consommation selective) dans les cours d'eau caracterises par un plus grand nombre de proies et des habitats plus simples (c.-a-d. les cours d'eau ou la capture de saumons est plus facile). Les ours etaient plus susceptibles, par une marge de 12 %, de consommer des poissons de maniere selective dans les cours d'eau etroits et peu profonds caracterises par un volume de fosses plus faible, dans lesquels les saumons sont plus faciles a capturer, que dans les cours d'eau larges et profonds. Cependant, les ours etaient aussi plus susceptibles, par une marge de 21 %, de consommer les poissons de maniere selective dans les cours d'eau presentant plus d'obstacles ligneux et de berges sapees, ou il etait predit que la chasse serait plus difficile. Cela indiquerait que les caracteristiques du cours d'eau peuvent avoir d'importants effets indirects sur les apports de nutriments riverains aux ecosystemes par l'entremise de l'alimentation selective des ours., Introduction Pacific salmon (Oncorhynchus spp.) are an important source of cross-boundary, marine-derived nutrient delivery to North Pacific coastal ecosystems. Salmon spend most of their lives growing in the sea, before [...]

The impacts of climate change are widespread and threaten natural systems globally. Yet, within regions, heterogeneous physical landscapes can differentially filter climate, leading to local response diversity. For example, it is possible that while freshwater lakes are sensitive to climate change, they may exhibit a diversity of thermal responses owing to their unique morphology, which in turn can differentially affect the growth and survival of vulnerable biota such as fishes. In particular, salmonids are cold‐water fishes with complex life histories shaped by diverse freshwater habitats that are sensitive to warming temperatures. Here we examine the influence of habitat on the growth of sockeye salmon (Oncorhynchus nerka) in nursery lakes of Canada's Skeena River watershed over a century of change in regional temperature and intraspecific competition. We found that freshwater growth has generally increased over the last century. While growth tended to be higher in years with relatively higher summer air temperatures (a proxy for lake temperature), long‐term increases in growth appear largely influenced by reduced competition. However, habitat played an important role in modulating the effect of high temperature. Specifically, growth was positively associated with rising temperatures in relatively deep (>50 m) nursery lakes, whereas warmer temperatures were not associated with a change in growth for fish among shallow lakes. The influence of temperature on growth also was modulated by glacier extent whereby the growth of fish from lakes situated in watersheds with little (i.e., <5%) glacier cover increased with rising temperatures, but decreased with rising temperatures for fish in lakes within more glaciated watersheds. Maintaining the integrity of an array of freshwater habitats—and the processes that generate and maintain them—will help foster a diverse climate‐response portfolio for important fish species, which in turn can ensure that salmon watersheds are resilient to future environmental change. [ABSTRACT FROM AUTHOR]

Canada's Policy for Conservation of Wild Pacific Salmon has been heralded as a transformative approach to the management of wild salmon whereby conservation is the highest priority. Given that changes to the Policy are under consideration, it is timely that we understand whether our state of knowledge and the status of wild salmon in Canada have indeed improved after its adoption in 2005. To answer these questions, we used two indices of improvement: (i) monitoring effort and (ii) abundance of spawning adults. Our results, based on data for all species from British Columbia's north and central coasts, show that monitoring effort has continued to erode, abundance of spawning adults has significantly declined for several species, the status of many salmon Conservation Units are in zones of concern, and 42% of the Conservation Units that we assessed as Red (threatened) would have improved in status had the Canadian fishery been reduced. We conclude with recommendations to help improve our knowledge of the status of salmon and enable a robust and successfully implemented Wild Salmon Policy for the future. La Politique du Canada pour la conservation du saumon sauvage du Pacifique a ete annoncee comme constituant une tranformation dans l'approche de gestion du saumon sauvage axee prioritairement sur la conservation. Comme la modification de la politique est actuellement a l'etude, il est opportun de se demander si l'etat des connaissances et le statut des saumons sauvages au Canada se sont effectivement ameliores apres l'adoption de la Politique en 2005. Pour repondre a ces questions, nous utilisons les deux indices d'amelioration suivants : (i) l'effort de surveillance et (ii) l'abondance des adultes geniteurs. Nos resultats, qui reposent sur des donnees pour toutes les especes le long du littoral nord et central de la Colombie-Britannique, montrent que l'effort de surveillance continue de s'eroder, que l'abondance des adultes geniteurs a diminue de maniere significative pour plusieurs especes, que le statut de nombreuses Unites de conservation du saumon est preoccupant et que le statut de 42% des Unites de conservation que nous avons evalue comme etant rouge (mauvais etat) se serait ameliore si la peche canadienne avait ete reduite. Nous concluons en formulant des recommandations pour aider a ameliorer les connaissances sur l'etat du saumon et permettre la mise en oeuvre efficace d'une politique sur le saumon sauvage a l'avenir. [Traduit par la Redaction], Introduction Canada's Policy for Conservation of Wild Pacific Salmon, referred to as the Wild Salmon Policy (WSP; DFO 2005), provides an integrated approach to the management of wild salmon (Oncorhynchus [...]