The 2024/25 winter spawning run of Central California Coast coho salmon (CCC) in the lower Russian River watershed brought fruition to ongoing local salmon recovery efforts. The data collected this last winter reveals an impressive return of adult coho salmon in the lower Russian River watershed and reinforces the importance of the Russian River Coho Salmon Captive Broodstock Program.
Since 2001, the Russian River Coho Salmon Captive Broodstock Program has closely monitored annual migration of coho salmon in the Russian River. A coalition consisting of the U.S. Army Corps of Engineers (USACE), the National Oceanic and Atmospheric Administration Fisheries Service (NOAA), the California Department of Fish and Wildlife (CDFW), Sonoma Water, and California Sea Grant, runs the program.
USACE Broodstock Program fisheries biologists operating from the Don Clausen Fish Hatchery at Warm Springs Dam spawn coho salmon from regional native stock. They have developed a spawning matrix in order to maintain genetic integrity, choosing the most distantly related adult coho salmon for breeding at the hatchery. When the juvenile coho grow to a suitable size, program personnel transport them from the hatchery and release them into historic coho tributaries in the lower Russian River watershed. The releases are part of an important salmon recovery technique known as “imprinting” in which juveniles develop a sense of natal origin. When imprinting is successful, the adult coho salmon return to the streams they were released in and spawn naturally.
Broodstock Program fisheries technicians monitoring Willow Creek, a major spawning and rearing tributary in the lower Russian River watershed, counted over 100 coho redds in the 2024/25 winter spawning run. This volume represents a record return since monitoring collection began in 2001. Prior to last season, the redd count record held in Willow Creek was just under 20.
Overall, preliminary data estimates 1,041 hatchery adults returned to the Russian River watershed, with over 250 naturally spawning in Willow Creek. Program personnel count returning adult coho using PIT tag antennae placed in various creeks throughout the watershed; finalized reporting will be released later in 2025.
During the 2023/24 winter run, streams along the Mendocino coastline also recorded their highest numbers in 16 years with over 15,000 adult coho counted. Many factors have contributed, including recent above-average annual rainfall amounts in the North Coast region. Moreover, commercial and recreational fishing for coho salmon has been prohibited for nearly 20 years. Investment in habitat restoration has also increased; NOAA alone spent over $80 million in habitat restoration and monitoring. CCC remain federally-listed as endangered, but fisheries biologists in the North Coast region are excited, nonetheless. CSPA commends and supports these ongoing efforts to promote natural spawning in California’s watersheds in hopes of the full recovery of Central Coast coho salmon.
