2018-2019 Coho Salmon Spawning Season Begins

Male and female pink salmon in Sitka National Historical Park, Alaska. Although these fish typically spawn in streams from Oregon to Alaska, individuals have been spotted in Lagunitas Creek for the second year in a row.

NPS / Ken Beck

A Surprise Visitor

November 2018 - Even before this seasons first rainfall, California Department of Fish and Wildlife staff had already spotted pink salmon in Lagunitas Creek for the second season in a row. Because they are usually found in streams from Oregon to Alaska, it is assumed that these fish have strayed here from other, more northern watersheds.

Spawners Need Rain

The spawning season started off dry, but Coho and Steelhead Monitoring Program surveys began the last week in November following the season’s first rainfall. Survey crews counted four live coho and one carcass on Olema Creek, and one live coho and one carcass on Redwood Creek. Although this number is small it is a good sign to have spawners returning this early in the season. Monitors don’t typically see peak coho spawning until late December, even in years with plentiful October and November rainfall.

The coho spawners arriving this winter were last seen during the winter of 2015–2016. At that time, biologists found 66 coho redds (nests) in Olema Creek and 15 in Redwood Creek. Hopefully ocean conditions were favorable during the spring of 2017 through the summer of 2018, and we can surpass those numbers this year. A much higher proportion of immature salmon (jacks) seen last year suggests ocean conditions may have indeed been favorable if these young coho were able to find enough food at sea to be large enough to return early.

Another Year of Coho Jumpstart Coming!

In August of 2016, approximately 200 juvenile coho from Redwood Creek were brought to the Don Clausen Fish Hatchery in a multi-agency collaborative rescue effort led by the California Department of Fish and Wildlife. After two years, these now adult fish are ready to be released once creek flows rise high enough. Stay tuned for updates as the season progresses.

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