Last updated: January 19, 2022
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December 2021 Rainfall Guides Coho Salmon Up West Marin Creeks
By Tara Blake and Natale Urquhart
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Adult coho salmon in the John West Fork tributary of Olema Creek. Almost three weeks of near-constant rainfall in December 2021 provided ideal conditions for spawning coho.
January 2022 - Almost three weeks of near-constant rainfall in December provided ideal conditions for spawning coho salmon. However, the survey conditions for our San Francisco Bay Area Network fisheries crew were less than ideal. High flows prevented us from performing regular weekly surveys. The water also remains quite murky, which makes it harder to spot fish and redds (fish nests). Despite the low visibility, our surveys and the salmon have carried on.
Since the coho spawning season started in late November, our crew has recorded coho in Olema, Redwood, and Cheda Creeks. In total, we've spotted over 150 coho adults. Olema Creek and its largest tributary, John West Fork, are hosting the majority of these fish with over 100 adult coho and 43 coho redds recorded. To date, live fish counts and redds on Olema are on par with the last time we saw this cohort in the winter of 2018-2019. Unlike the Chinook observed in the fall, current coho spawners are likely naturally born (as opposed to being hatchery-raised), so seeing them in high numbers at this point in the season is encouraging.
NPS / Michael Reichmuth
During this time of the year, steelhead trout are often observed swimming alongside coho salmon. So far, we've only found three live steelhead and two steelhead redds. It is still early in their spawning season though, and we anticipate seeing more in the coming months.
For more information
- San Francisco Bay Area Network Salmonid Monitoring webpage
- Pacific Coast Science & Learning Center Coho & Steelhead webpage
- Contact Fishery Biologist Michael Reichmuth
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