Coho Spawners Come Up Short in 2019-2020, but Steelhead Return Looking Strong

Volunteers and a biologist hike along a creek towards the next calm reach where there might be coho or steelhead redds to count and measure.

NPS / Jessica Weinberg McClosky

February 2020 - Recent surveys revealed the coho run has ended for our coastal Marin streams. Overall, coho spawning numbers were lower than anticipated, even with beneficial December rainfall. Surveys will continue through April to document steelhead spawning.

On Redwood Creek, salmonid monitoring teams made up of staff and volunteers counted three live adult coho and three coho redds (nests). They also observed adult steelhead in the stream beginning at the end of December which is a bit earlier than usual. We are now halfway through the typical steelhead spawning season, and redd numbers (22 so far) look promising for a second strong season in a row. Biologists could not confirm which species constructed eight additional redds on Redwood Creek.

On Olema Creek, monitoring teams counted a total of two coho redds, 17 live adult coho, and three coho carcasses. In addition,they observed five live steelhead adults, one steelhead carcass, and seven steelhead redds. Only one redd was counted for which salmonid species could not be determined. Most of the live coho adults were observed holding in pools for several weeks in January. They appeared to be male and were likely waiting on late-season females to migrate upstream.

Surveys were also performed on Pine Gulch and Cheda Creeks this season. On Cheda Creek, a small tributary to Lagunitas Creek, survey teams found one redd for which the salmonid species could not be identified. On Pine Gulch, they counted one live adult steelhead and 17 steelhead redds. Contact Michael Reichmuth to learn more.

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