Coldwater, stenothermic fish seem bound to suffer under the spectre of future warming

Journal of Great Lakes Research, Journal Year: 2024, Volume and Issue: 50(3), P. 102351 - 102351

Published: May 1, 2024

Climate change has the potential to impact lacustrine fish populations by affecting both their physiologies and phenologies. Coldwater, stenothermic fishes that spawn in winter may be at highest risk of being negatively impacted predicted future climate warming. To investigate this subject, we tested temperature on embryonic larval stages coldwater, salmonid whitefishes (coregonines). Embryos two coregonine species from Upper Lake Constance (a large, deep perialpine lake bordering Austria, Germany Switzerland) were incubated three temperatures approximating historic water temperatures. After hatching, larvae all incubation treatments transferred rearing treatments. Hatching times advanced higher temperatures, whilst mortality performance responses generally negative, suggesting warming will reduce recruitment Constance. The varied specific sensitivity temperature. Additionally, found affected up a half months after hatching. Using our data hatching times, infer could advance phenologies weeks end 21st century.

Language: Английский

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Sexual selection matters in genetic rescue, but productivity benefits fade over time: a multi-generation experiment to inform conservation

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2025, Volume and Issue: 292(2039)

Published: Jan. 1, 2025

Globally, many species are threatened by population decline because of anthropogenic changes leading to fragmentation, genetic isolation and inbreeding depression. Genetic rescue, the controlled introduction variation, is a method used relieve such effects in small populations. However, without understanding how characteristics rescuers impact rescue attempts interventions run risk being sub-optimal, or even counterproductive. We use red flour beetle ( Tribolium castaneum ) test rescuer sex, sexual selection background, on productivity. record productivity 24 36 replicated populations for ten generations following intervention. find little no sex efficacy but show that background elevated makes individuals more effective rescuers. In both experiments, diminish 6–10 after rescue. Our results confirm can be influenced level rescuing an important factor. any increase fitness associated with may last limited number generations, suggesting implications conservation policy practice.

Language: Английский

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Genome-Assisted Gene-Flow Rescued Genetic Diversity Without Hindering Growth Performance in an Inbred Coho Salmon (Oncorhynchus kisutch) Population Selected for High Growth Phenotype

Marine Biotechnology, Journal Year: 2025, Volume and Issue: 27(1)

Published: Feb. 1, 2025

Abstract Selective breeding is a powerful tool for improving aquaculture production. A well-managed program essential, as populations can otherwise lose genetic diversity, leading to reduced selection response and inbreeding excesses. In such cases, diversity in broodstock must be restored by introducing individuals from external populations. However, this reduce the accumulated gains selective breeding. introduction of with superior phenotypes will allow restoration without sacrificing these gains. study, we demonstrated possibility using selectively bred (SB) randomly (RB) population coho salmon ( Oncorhynchus kisutch ). Forty males growth were selected RB genomic crossed 127 collected females SB population, producing newly (NB) population. Genetic assessed statistics effective number alleles, allele richness, observed heterozygosity 11 microsatellite markers, was higher NB than RB. Additionally, fork length body weight compared among three after 12 months post-fertilization common tanks. The least-squares means similar between (164.9 mm 57.9 g) (161.1 53.7 g), while both significantly greater (150.4 43.0 g). Our results highlight effectiveness genome-assisted gene flow restoring compromising gain growth.

Language: Английский

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Variation in Salmon Migration Phenology Bolsters Population Stability but Is Threatened by Drought

Ecology Letters, Journal Year: 2025, Volume and Issue: 28(2)

Published: Feb. 1, 2025

ABSTRACT Intrapopulation variation in movement is common nature but its effects on population dynamics are poorly understood. Using data from 3270 individually‐marked fish representing nine cohorts of coho salmon ( Oncorhynchus kisutch ) California, we show that bimodal intrapopulation the timing juvenile down‐migration their natal habitat and subsequent residence non‐natal affects growth, emigration timing, abundance stability adult returns. Non‐natal (early down‐migrants) exhibited more variable growth earlier to estuary than (late down‐migrants). While rearing was common, were overrepresented among returns, total returns 1.4 times stable alone. Our results demonstrate migratory behaviour bolsters stability. However, reduced low water years, suggesting drought exacerbates instability by reducing critical variation.

Language: Английский

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Genomic Insights Into Inbreeding and Adaptive Divergence of Trout Populations to Inform Genetic Rescue

Evolutionary Applications, Journal Year: 2025, Volume and Issue: 18(3)

Published: March 1, 2025

Genetic rescue, specifically translocation to facilitate gene flow among populations and reduce the effects of inbreeding, is an increasingly used approach in conservation. However, this comes with trade-offs, wherein may fitness when have adaptive differentiation (i.e., outbreeding depression). A better understanding interaction between isolation, divergence key traits, such as life history will help inform genetic rescue efforts. Stream-dwelling salmonids, westslope cutthroat trout (Oncorhynchus lewisi; WCT), are well-suited for examining these trade-offs because they isolated by habitat degradation, exhibit substantial variation traits populations, include many species conservation concern. few genomic studies examined potential inbreeding versus depression salmonids. We > 150,000 SNPs examine coefficients 565 individuals across 25 WCT that differed their isolation status demographic histories. Analyses runs homozygosity revealed several had "flatlined" having extremely low high coefficients. Additionally, we conducted genome scans identify outlier loci could explain differences 10 populations. Genome identified one candidate region influenced maximum length age-1 age-2 growth. limited number suggests be driven genes small effect or phenotypic plasticity. Although should considered, suggest benefit most genetically depauperate

Language: Английский

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Anatomy of a range contraction: Flow–phenology mismatches threaten salmonid fishes near their trailing edge

Proceedings of the National Academy of Sciences, Journal Year: 2025, Volume and Issue: 122(14)

Published: March 31, 2025

Climate change is redistributing life on Earth, with profound impacts for ecosystems and human well-being. While repeat surveys separated by multidecadal intervals can determine whether observed shifts are in the expected direction (e.g., poleward or upslope due to climate change), they do not reveal their mechanisms time scales: were gradual responses environmental trends punctuated disturbance events. Here, we document population reductions temporary range contractions at multiple sites resulting from drought three Pacific salmonids ranges’ trailing edge. During California’s 2012 2016 historic multiyear drought, 2013 2014 winter stood apart because rainfall was both reduced delayed. Extremely low river flows during breeding season (“flow–phenology mismatch”) precluded access habitat. Chinook ( Oncorhynchus tshawytscha) experienced a down-river shift, entire cohorts failed individual tributaries (steelhead trout, O. mykiss ) watersheds (coho salmon, kisutch) . Salmonids returned impacted subsequent years, rescued reserves ocean, history diversity, and, one case, conservation broodstock program. Large losses can, however, leave trailing-edge populations vulnerable extinction demographic stochasticity, making permanent contraction more likely. When only few large storms occur high flow season, timing of particular plays an outsized role determining which migratory fish species able riverine grounds persist.

Language: Английский

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Putting Structural Variants Into Practice: The Role of Chromosomal Inversions in the Management of Marine Environments

Molecular Ecology, Journal Year: 2025, Volume and Issue: unknown

Published: May 8, 2025

ABSTRACT Major threats to marine species and ecosystems include overfishing, invasive species, pollution climate change. The changing not only imposes direct through the impacts of severe heatwaves, cyclones ocean acidification but also complicates fisheries management by driving range shifts. dynamic nature these means that future our oceans will depend on ability adapt. This has led calls for genetic interventions focussed enhancing species' adaptive capacity, including translocations, restocking selective breeding. Assessing benefits risks such approaches requires an improved understanding architecture variation, in relation climate‐resilient phenotypes locally adapted populations fitness hybrids. Large structural variants as chromosomal inversions play important role local adaptation linking multiple loci. Consequently, are likely be particularly when managing capacity. However, under some circumstances, they accumulate deleterious mutations, potentially increasing risk inbreeding depression. Genetic takes account dual roles is more effective at ensuring population persistence. We summarise evolutionary factors influencing variation inversions, review found taxa, provide a framework predict consequences ignoring key scenarios. conclude describing practical methods bridge gap between theory application conservation.

Language: Английский

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Comparing the ecological consequences of globally invasive fishes versus their F1 hybrids in recreational fisheries

Published: May 13, 2024

Recreational angling is a major introduction pathway for non-native fish into freshwaters, where multiple fishes are often released waterbodies to diversify the opportunities. When these taxonomically similar, then there concern that their hybridisation will result in F1 generations comprising of novel phenotypes outperform parental species, resulting impacts ecological engineering species being accelerated. Across two water temperatures (18 o C, 26 C), comparative functional response analyses (CFR) quantified consumption patterns globally invasive freshwater carp Cyprinus carpio and goldfish Carassius auratus, plus hybrids, before testing differences specific growth rates (SGRs). In CFRs, consumed significantly more prey at 18 C than other fishes, with no between any C. SGRs also did not differ substantially either temperature. These results suggest high impacting produce performance could accelerate invaded ecosystems. Accordingly, risks use recreational remain an issue primarily associated parent populations, this can be reflected invasion management.

Language: Английский

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Reintroduction of spring‐run Chinook salmon in the San Joaquin River: Evaluating genetic and phenotypic effects of captive breeding

Conservation Science and Practice, Journal Year: 2024, Volume and Issue: 6(9)

Published: Aug. 23, 2024

Abstract Captive‐breeding programs are increasingly implemented to curb population declines but can have unintended negative effects on genetic diversity and phenotypes. Through an analysis of ~10 years monitoring, pedigree information, phenotypic data, we evaluated a captive‐breeding program that uses adaptive management reduce inbreeding improve captive broodstock performance. A was established in 2012 reintroduce spring‐run Chinook salmon the southern edge their range California's San Joaquin River (SJR), using fish produced each year at nearby Feather Hatchery (FRH). We found SJR adequately captured FRH source mate pairings guided by relatedness reduced inbreeding. However, reared captivity had smaller body size maturity comparison which matures sea, this effect disappeared when juveniles were released from mature sea. Phenotypic traits female parents also influenced reproductive performance; older mothers those with eggs offspring lower survival. These findings demonstrate monitoring information be powerful tools for reducing risks breeding evaluating effectiveness.

Language: Английский

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Genomic‐Guided Conservation Actions to Restore the Most Endangered Conifer in the Mediterranean Basin

Molecular Ecology, Journal Year: 2024, Volume and Issue: unknown

Published: Dec. 6, 2024

ABSTRACT Species with extremely small population sizes are critically endangered because of reduced genetic diversity, increased inbreeding and hybridisation threats. Genomic tools significantly advance conservation by revealing insights into species, notably in monitoring frameworks. Sicilian fir ( Abies nebrodensis ) is the most conifer Europe only 30 adult trees an 84‐ha area. Using 20,824 SNPs from RAD‐seq, employing genome assembly a custom 120 SNP‐array, we evaluated mating patterns, effective size trees, 118 natural seedlings, 2064 nursery seedlings past actions. We assessed introgression neighbouring non‐native plantations (~6%) established intra‐population assisted gene flow (AGF) program selecting genetically dissimilar individuals investigating outcome through simulations. analysis unveiled significant diversity among firs, comparable to non‐endangered Mediterranean firs larger populations. However, forthcoming generation declined due high self‐fertilisation, leading marked F IS = 0.38) alarmingly low N e 6). Nursery seedling revealed similar selfing rates (~2%) firs. Although AGF could help mitigate loss, it may not alleviate species vulnerability imminent environmental challenges, perpetuating risk extinction vortex. Hence, impact decline on depression, along exploring potential hybrids for load alleviation future adaptation, crucial strategies.

Language: Английский

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