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Abstract Glacier retreat poses risks and benefits for species of cultural and economic importance. One example is Pacific salmon ( Oncorhynchus spp.), supporting subsistence harvests, and commercial and recreational fisheries worth billions of dollars annually. Although decreases in summer streamflow and warming freshwater is reducing salmon habitat quality in parts of their range, glacier retreat is creating new streams and lakes that salmon can colonize. However, potential gains in future salmon habitat associated with glacier loss have yet to be quantified across the range of Pacific salmon. Here we project future gains in Pacific salmon freshwater habitat by linking a model of glacier mass change for 315 glaciers, forced by five different Global Climate Models, with a simple model of salmon stream habitat potential throughout the Pacific Mountain ranges of western North America. We project that by the year 2100 glacier retreat will create 6,146 (±1,619) km of new streams accessible for colonization by Pacific salmon, of which 1,930 (±569) km have the potential to be used for spawning and juvenile rearing, representing 0 to 27% gains within the 18 sub-regions we studied. These findings can inform proactive management and conservation of Pacific salmon in this era of rapid climate change.
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Species distribution models estimate time-varying juvenile salmon distributions in the north- and southeastern Bering Sea
This study compares alternative implementations of species distribution models (SDMs) for quantifying static and dynamic patterns in marine habitat use, with a case study focusing on juvenile salmon in the eastern Bering Sea. We compare the performance of two prevalent SDM frameworks—generalized additive models (GAMs) and vector autoregressive spatio-temporal (VAST) models—in predicting juvenile salmon distributions and assessing interannual variation in habitat utilization. The two SDM frameworks produced similar spatial predictions but performed differently in tests of within-sample and out-of-sample predictive power. Our findings indicate that VAST models may provide more precise estimates of distribution compared to GAMs. Maps of predicted juvenile salmon distributions showed highest salmon densities in habitats within the 50 m isobath of the continental shelf, underscoring the importance of these coastal areas, although among-species differences were evident. Model performance results suggested evidence for spatial variation in juvenile salmon species’ distributions through time. Our findings suggest that an SDM approach can be effective for estimating static and dynamic juvenile salmon distributions, and for providing insights that are useful in spatial fisheries management contexts.
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- Award ID(s):
- 2022190
- PAR ID:
- 10658081
- Publisher / Repository:
- Canadian Journal of Fisheries and Aquatic Sciences
- Date Published:
- Journal Name:
- Canadian Journal of Fisheries and Aquatic Sciences
- Volume:
- 82
- ISSN:
- 0706-652X
- Page Range / eLocation ID:
- 1 to 13
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1139/cjfas-2024-0137
