Wednesday June 29, 2022
PhysOrg —
Salmon famously travel hundreds of miles upstream to reach their home waters to spawn, but climate change is shrinking their destination. A new study offers high-resolution details on how Chinook salmon habitats are being lost on Bear Valley Creek, a headwater stream of the Salmon River in central Idaho.
The study, published today in the AGU journal Geophysical Research Letters, suggests lower water volumes and warming temperatures are dramatically shrinking spawning beds and nurseries for the culturally and economically important fish. Researchers predict salmon here could lose nearly half their total habitat in this river as soon as 2040 due to an estimated 50% decrease in river discharge.
Daniele Tonina, lead author of the new study and a professor of ecohydraulics at the University of Idaho, and colleagues examined a 14-kilometer stretch of Bear Valley Creek, which is known for hosting a robust population of Chinook salmon. With a wide valley, meandering main river and cozy side-streams, the site is representative of ideal salmon habitats in the Pacific Northwest.