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Marine heatwaves shape size‐dependent thermal exposure, habitat use and marine residency in Arctic char ( Salvelinus alpinus )NARA Subscribed
Marine heatwaves (MHWs) are increasing in high‐latitude oceans, yet behavioural responses of anadromous fishes to these potential stressors during short marine feeding seasons remain poorly understood. We combined acoustic telemetry (internal temperature and depth) with satellite‐derived sea surface temperature data to quantify Arctic char ( Salvelinus alpinus ) responses to MHWs in the coastal Labrador Sea across two contrast...
Variability in Fecundity–Body Size Relationships for Atlantic Salmon Associated With Body Condition and Life HistoryNARA Subscribed
While body size is the primary driver of fecundity, other factors may contribute to variation in these relationships. Anadromous populations of Atlantic salmon ( Salmo salar ) have diverse life histories, and fisheries management relies on accurate fecundity estimates. We used Bayesian hierarchical models to determine the relationship between fecundity and fork length, and other life‐history characteristics, for 25 spawning po...
Angler demographics and motivations are an important consideration to successful fisheries management. We examined 29 years of angler license and activity records from the recreational Atlantic salmon fishery in Newfoundland and Labrador, Canada to: (1) provide a contemporary evaluation of angler demographic trends; (2) evaluate age and regional differences between anglers who prioritized retention versus catch‐and‐release; an...
Assessing resource use as a predictor for Atlantic salmon ( Salmo salar ) smolt body sizeNARA Subscribed
Atlantic salmon ( Salmo salar ) have experienced significant population declines in eastern Canada for the past 30 years, primarily attributed to at‐sea mortality. To identify factors contributing to smolt body size, which has been associated with variations in survival, we examined various predictors in linear mixed‐effect models using data from out‐migrating smolts collected from 2000 to 2016 at three rivers: Conne River (NF...
Salmonids in hot water: An unprecedented warm‐water event in Labrador, a subarctic region of CanadaNARA Subscribed
Unprecedented warm river temperatures in July 2023 in Labrador, a subarctic region of Canada, were the highest since monitoring began (1994–2023) and ranged from 19.4°C (Hunt River) to 22.5°C (Eagle River). Incipient lethal water temperatures were exceeded for adult Atlantic salmon and brook trout (≥25°C) on 14 days in five of seven rivers and Arctic charr (≥24°C) on 17 days in six of seven rivers. Consequently, Labrador had t...
Illegal incidents and violations related to Atlantic salmon fishing in Newfoundland and Labrador, Canada, during 2001–2020NARA Subscribed
Resource user compliance is a key element in effective fisheries management. Herein, we examine two decades of enforcement records pertaining to Atlantic salmon from Newfoundland and Labrador, Canada. Illegal incidents were negatively correlated with the number of licensed anglers but not salmon abundance. Over two decades, illegal incidents declined by 66%, even after correcting for the positive relationship between enforceme...
We describe observations of sea lamprey ( Petromyzon marinus ) and striped bass ( Morone saxatilis ) incursions into Labrador, Canada. While P. marinus have been periodically observed in similar latitudes, their numbers have conspicuously increased in estuarine environments in 2020. In contrast, M. saxatilis were not observed from Labrador until 2017 but appear to be declining after the initial surge in abundance that peaked i...
The post‐glacial colonization of Gander Lake in Newfoundland, Canada, by Arctic Charr ( Salvelinus alpinus) provides the opportunity to study the genomic basis of adaptation to extreme deep‐water environments. Colonization of deep‐water (>50 m) habitats often requires extensive adaptation to cope with novel environmental challenges from high hydrostatic pressure, low temperature, and low light, but the genomic mechanisms under...
Warming water temperatures, combined with increased mortality following catch and release, could have synergistic consequences if rivers remain open to catch and release at high water temperatures, and catchability of fish remains similar across water temperatures. Here archived data for Atlantic salmon, Salmo salar L., were used to (a) quantify the influence of water temperature on catchability and (b) refine estimates of abs...
Investigations on the marine feeding of Atlantic salmon ( Salmo salar L.) in the Northwest Atlantic are limited compared with the Northeast Atlantic. Climate‐induced changes to food webs in Atlantic salmon feeding areas have been noted, alongside increased mortality despite a cessation of most marine fisheries. As forage efficiency may be hampering survival, it was important to address this knowledge gap. Atlantic salmon were...
Identification of discrete and unique assemblages of individuals or populations is central to the management of exploited species. Advances in population genomics provide new opportunities for re‐evaluating existing conservation units but comparisons among approaches remain rare. We compare the utility of RAD ‐seq, a single nucleotide polymorphism ( SNP ) array and a microsatellite panel to resolve spatial structuring under a...
Migrations between different habitats are key events in the lives of many organisms. Such movements involve annually recurring travel over long distances usually triggered by seasonal changes in the environment. Often, the migration is associated with travel to or from reproduction areas to regions of growth. Young anadromous Atlantic salmon ( Salmo salar ) emigrate from freshwater nursery areas during spring and early summer...
A perspective on Salvelinus researchNARA Subscribed
Eleven Arctic charr ( Salvelinus alpinus ) (370–512 mm) and eight sea trout ( Salmo trutta ) (370–585 mm in length) were tagged externally or internally with depth‐ and temperature‐measuring data‐storage tags (DST) before they were released into the sea in the Alta Fjord in north Norway in June 2002. All sea trout were recaptured after they spent 1–40 days at sea, while all Arctic charr were recaptured after 0.5–33 days at sea...
Thermal habitat experienced by Atlantic salmon ( Salmo salar L.) kelts in coastal Newfoundland watersNARA Subscribed
Thermal habitat was recorded by data storage tags (DSTs) applied to Atlantic salmon ( Salmo salar L.) kelts during their seaward migration in the spring of 1998 at enumeration facilities in Highlands River, Humber River, Western Arm Brook, and Campbellton River, Newfoundland. In total, 139 DSTs were applied and data were downloaded from eleven of the recovered tags. The recovered tags had been applied at Highlands, Campbellton...
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