Wednesday February 26, 2025
PhysOrg —
New research from the Stone Center published today in Ecology Letters finds that coho salmon, 1 of 5 Pacific salmon species, have more dynamic migration patterns than previously thought. The study reveals these alternative life histories made coho populations more stable over time, which could be a missing piece in conservation research and action more broadly.
Salmon are keystone species (they play an essential role in the health and function of their larger ecosystems) and coho are endangered in California. Researchers with UC Berkeley and California Sea Grant led the 12-year-long study in Willow Creek, a tributary to the Russian River located in northern California’s Sonoma County, to evaluate the effectiveness of salmon restoration efforts.
“It’s commonly thought that, during their first year of life in freshwater, coho live and eat near to where they hatched prior to migrating to the ocean for adulthood,” said Dr. Hank Baker, lead author of the paper and postdoctoral researcher within the Carlson and Grantham labs and Freshwater Group at UC Berkeley.
“However, we noticed that some individuals leave their natal habitat early and spend months in other parts of the river network before migrating. We found that this subtle diversity within the population contributed quite dramatically to a more robust and stable population overall.” The effect is similar to that of a well-diversified financial portfolio, according to Baker.