North American diadromous fishes: Drivers of decline and potential for recovery in the Anthropocene

Science Advances, Journal Year: 2022, Volume and Issue: 8(4)

Published: Jan. 28, 2022

Diadromous fishes migrate between freshwater and marine habitats to complete their life cycle, a complexity that makes them vulnerable the adverse effects of current past human activities on land in oceans. Many North American species are critically endangered, entire populations have been lost. Major factors driving declines include overfishing, pollution, water withdrawals, aquaculture, non-native species, habitat degradation, over-zealous application hatcheries designed mitigate other factors, climate change. Perhaps, most broadly tractable effective affecting diadromous removals dams prevent or hinder migrations, alter environment, often favor biotic communities. Future survival many fish may depend this.

Language: Английский

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Cold-water habitats, climate refugia, and their utility for conserving salmonid fishes

Canadian Journal of Fisheries and Aquatic Sciences, Journal Year: 2023, Volume and Issue: 80(7), P. 1187 - 1206

Published: March 15, 2023

Anthropogenic climate change is warming global temperatures, with significant implications for salmonid fishes that depend on the availability of cold water during one or more life stages. Along southern range extents many species, and elsewhere warm temperatures are increasingly problematic, identification protection restoration habitats may serve as refugia where local populations can persist emerging an important conservation tactic. In this perspective piece, we address concept utility refugia—drawing a distinction commonly considered thermal refuges—describe technological advances enable accurate temperature mapping species distribution modeling in lotic environments, outline key uncertainties opportunities to chart constructive path forward topic will continue grow importance. Identifying not panacea conservation, but argue there tangible benefits doing so, least which options it affords thinking acting strategically within context changing century.

Language: Английский

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An evaluation of the potential factors affecting lifetime reproductive success in salmonids

Evolutionary Applications, Journal Year: 2021, Volume and Issue: 14(8), P. 1929 - 1957

Published: June 9, 2021

Abstract Lifetime reproductive success (LRS), the number of offspring produced over an organism's lifetime, is a fundamental component Darwinian fitness. For taxa such as salmonids with multiple species conservation concern, understanding factors affecting LRS critical for development and implementation successful management practices. Here, we reviewed published literature to synthesize in including significant effects hatchery rearing, life history, phenotypic variation, behavioral spawning interactions. Additionally, found that affected by competitive behavior on grounds, genetic compatibility, local adaptation, hybridization. Our review existing revealed limitations studies, emphasize following areas warrant further attention future research: (1) expanding range studies assessing across different life‐history strategies, specifically accounting distinct migratory phenotypes; (2) broadening variety represented salmonid fitness studies; (3) constructing multigenerational pedigrees track long‐term effects; (4) conducting investigate aquatic stressors, anthropogenic effects, pathogens, environmental both freshwater marine environments, overall body condition, (5) utilizing appropriate statistical approaches determine explain greatest variation providing information regarding biological significance, power limitations, potential sources error parentage studies. Overall, this emphasizes have profoundly advanced scientific fitness, but substantial challenges need be overcome assist recovery these keystone ecosystems.

Language: Английский

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Trends in Chinook salmon spawner abundance and total run size highlight linkages between life history, geography and decline

Fish and Fisheries, Journal Year: 2023, Volume and Issue: 24(4), P. 595 - 617

Published: April 18, 2023

Abstract Chinook salmon ( Oncorhynchus tshawytscha , Salmonidae) are foundational to social‐ecological systems of the Northeast Pacific Rim and exhibit a rich diversity life histories including in their adult migration timing, age at critical life‐history transitions marine feeding distributions. In recent decades have experienced declines across much native range; however, changes productivity abundance rarely been evaluated relation variation. To understand trends production, how they related history, we compiled time series data from Fraser River Sacramento on total run size (pre‐fishery abundance) escapement (post‐fishery spawner fit models estimate this bioregion. Our analysis revealed that most populations declining, with negative (57 79) (16 23) size. Trends were acutely for interior spring Fraser, Columbia Snake Rivers California. Summer fall had mixed trends, several summer upriver bright exhibiting increases 1990s 2019. research reveals widespread important species, but local complexity mediated by population‐level migratory behaviours watershed‐scale restoration actions. Understanding linkages between resilience should inform rebuilding efforts highlight need conserve intraspecific biodiversity.

Language: Английский

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Adult spawners: A critical period for subarctic Chinook salmon in a changing climate

Global Change Biology, Journal Year: 2023, Volume and Issue: 29(7), P. 1759 - 1773

Published: Jan. 20, 2023

Abstract Concurrent, distribution‐wide abundance declines of some Pacific salmon species, including Chinook ( Oncorhynchus tshawytscha ), highlights the need to understand how vulnerability at different life stages climate stressors affects population dynamics and fisheries sustainability. Yukon River stocks are among largest subarctic populations, near northernmost extent species range. Existing research suggests that largely driven by factors occurring between adult spawner stage their offspring's first summer sea (second year post‐hatching). However, specific mechanisms sustaining chronic poor productivity unknown, there is a tremendous sense urgency causes, as these have taken serious toll on commercial, recreational, indigenous subsistence fisheries. Therefore, we leveraged multiple existing datasets spanning parent juvenile history in freshwater marine habitats. We analyzed environmental data association with production offspring survive (juveniles per spawner). These analyses suggest more than 45% variability associated river temperatures or water discharge levels during spawning migration. Over past two decades, parents experienced warmer lower mainstem produced fewer juveniles adult. propose critical period regulating dynamics. also conceptual model can explain associations using independent focused nutrition heat stress. It sobering consider habitats may already be unfavorable cold‐water species. Our findings immediate implications, given common assumption northern ranges offer refugia from stressors.

Language: Английский

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A Comprehensive Review of the Impacts of Climate Change on Salmon: Strengths and Weaknesses of the Literature by Life Stage

Fishes, Journal Year: 2023, Volume and Issue: 8(6), P. 319 - 319

Published: June 16, 2023

As we confront novel environmental challenges, a full understanding of the physical and biological processes that govern species responses to climate change will help maintain biodiversity support conservation measures are more robust irreducible uncertainty. However, impacts so complex, literature on salmon trout is vast researchers decision makers scramble make sense it all. Therefore, conducted systematic review anadromous as resource for stakeholders, managers, researchers. We reviewed studies published from 2010 2021 address these fish organized them in database 1169 1853 papers. Papers labeled with keywords across eight categories related subject matter study methods. compared by process life stage used comparisons assess strengths weaknesses. then summarized expected phenotypic genetic management actions stage. Overall, found largest research gaps interactions, behavioral responses, effects carry over stages. With this collection literature, can better apply scarce resources, fill knowledge gaps, informed decisions do not ignore

Language: Английский

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Behavioural responses to acute warming precede critical shifts in the cellular and physiological thermal stress responses in a salmonid fish (brook trout, Salvelinus fontinalis)

Journal of Experimental Biology, Journal Year: 2025, Volume and Issue: 228(3)

Published: Jan. 8, 2025

ABSTRACT From a conservation perspective, it is important to identify when sub-lethal temperatures begin adversely impact an organism. However, unclear whether, during acute exposures, cellular thresholds occur at similar other physiological or behavioural changes, associated with common endpoints measured in fishes estimate thermal tolerance. To test this, we estimated temperature preference (15.1±1.1°C, mean±s.d.) using shuttle box, agitation (22.0±1.4°C), defined as the point where fish exhibits avoidance response, and upper limit (CTmax, 28.2±0.4°C) for 1 year old brook trout (Salvelinus fontinalis) acclimated 10°C. We then acutely exposed different subset of mean pre-determined sampled tissues they reached target after 60 min recovery 10°C transcriptomic analysis. used qPCR mRNA transcript levels genes heat shock proteins, oxidative stress, apoptosis inducible transcription factors. A major shift transcriptome response occurred once was reached, which may possible link between stress response.

Language: Английский

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Tidal–hydrological dynamics of water temperature across freshwater forested wetlands on the northeastern Pacific coast

JAWRA Journal of the American Water Resources Association, Journal Year: 2025, Volume and Issue: 61(1)

Published: Jan. 2, 2025

Abstract Tidal freshwater forests were once extensive across temperate coastlines, but loss and fragmentation have made estimation of their ecosystem functions challenging. We measured water temperature for 2 years in three Sitka spruce tidal forests, a restoration site, an adjacent emergent marsh on the Columbia River, Washington, United States. assessed spatial variability within sites including effects hydrology, differences among bay tributary between mainstem Columbia, marsh. The nearest to had lower interior temperatures than channel confluences by up 2.5°C (weekly median temperature) 2.0°C maximum temperature), with most cooling occurring during low‐flow months July–September. Tributary 1.9°C cooler 4.2°C mainstem. Temperatures two decreased −0.16°C/100 m −0.07°C/100 m, average. site smallest within‐site gradient. Differences greatest when range was low, while higher ranges associated warmer more variable interiors relative confluences. These results suggest that these can provide refugia cold biota salmon.

Language: Английский

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From threats to solutions: A literature review of climate adaptation in anadromous salmon and trout

Ecosphere, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 1, 2025

Abstract Understanding the evolutionary responses of anadromous salmon and trout to climate change is critical for effective conservation planning. In this study, we conducted a comprehensive review literature published from 2010 2020 synthesize current knowledge on impacts these fish populations. Specifically, focused 199 papers that explored processes in response changing environmental conditions. Our analysis revealed several key themes, including interwoven influences human activities genetic variation, phenotypic traits, population dynamics. We found geographic patterns diversity are closely linked climatic gradients, highlighting importance strategies variation existing adaptive capacity. Additionally, temporal trends phenology, maturation age, fecundity indicate ongoing plastic change. Importantly, were identified as significant drivers maladaptation emphasize need targeted monitoring specific mitigate loss enhance study underscores identifying protecting areas high rare genes, particularly regions projected experience rapid shifts. conclusion, our findings identify strengths gaps research investigating role dynamics face By capitalizing new tools sequencing, genomic analysis, automated field data collection, can establish baselines tracking Better integration into projections future will lead more ensure long‐term resilience iconic species other wildlife.

Language: Английский

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River environment effects on adult migration phenology and rate of spring-run Chinook Salmon

Transactions of the American Fisheries Society, Journal Year: 2025, Volume and Issue: unknown

Published: March 18, 2025

ABSTRACT Objective Our overarching objective was to better understand how river environment affects the migration phenology and behavior of adult Chinook Salmon Oncorhynchus tshawytscha in a watershed (Oregon’s Willamette River basin) where climate warming other habitat impacts threaten spring-run population. Methods We analyzed annual spring runs using 23-year time series daily counts at Falls (river kilometer 42, measuring from River–Columbia confluence) relation discharge temperature data nearby gauge site. also examined stock-specific upstream rates with general linear models monitoring 909 radio-tagged explore effects fish traits on movement through 13 main-stem tributary reaches. Results migrated earlier warm, low-flow years. Mean conditions May were best predictors median run timing dates, which ranged early mid-June. Radio-tagged salmon moved faster when temperatures higher lower. Tagged much (∼25–50 km/d) low-gradient reaches than steeper (mostly <10 km/d). Individual traits, including stock origin, generally not statistically associated rate after accounting for water discharge. Phenology results Yukon, Columbia, Snake basins broadly aligned those basin. Conclusions study offer mechanistic explanation why migrations occur warmer years across broad geographic range. The suggest that some spring-migrating populations may continue trend earlier, behaviorally plastic response uncertain implications. Of particular concern are risks presented by increased freshwater residency like upper Salmon.

Language: Английский

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