Thermal sensitivity and flow-mediated migratory delays drive climate risk for coastal sockeye salmon
Back to previous page
| Authors: | Atlas, WI; Seitz, KM; Jorgenson, JWN; Millard-Martin, B; Housty, WG; Ramos-Espinoza, D; Burnett, NJ; Reid, M; Moore, JW |
| Year: | 2021 |
| Journal: | Facets 6: 71-89 Article Link (DOI) |
| Title: | Thermal sensitivity and flow-mediated migratory delays drive climate risk for coastal sockeye salmon |
| Abstract: | Climate change is subjecting aquatic species to increasing temperatures and shifting hydrologic conditions. Understanding how these changes affect individual survival can help guide conservation and management actions. Anadromous Pacific salmon (Oncorhynchus spp.) in some large river systems are acutely impacted by the river temperatures and flows encountered during their spawning migrations. However, comparatively little is known about drivers of en route mortality for salmon in smaller coastal watersheds, and climate impacts may differ across watersheds and locally adapted salmon populations. To understand the effects of climate on the survival of coastal sockeye salmon (Oncorhynchus nerka; hIsn in Hailzaqv), we tagged 1785 individual fish with passive integrated transponders across four migration seasons in the Koeye River-a low-elevation watershed in coastal British Columbia-and tracked them during their relatively short migration (similar to 13 km) from river entry to spawning grounds. Overall, 64.7% of sockeye survived to enter the spawning grounds, and survival decreased rapidly when water temperatures exceeded 15 degrees C. The best-fitting model included an interaction between river flow and temperature, such that temperature effects were worse when flows were low, and river entry ceased at the lowest flows. Results revealed temperature-mediated mortality and migration delays from low water that may synergistically reduce survival among sockeye salmon returning to coastal watersheds. |
Please send suggestions for improving this publication database to
sass-support@sfu.ca.
Departmental members may update their publication list.