Preliminary Summer 2018 Juvenile Salmonid Survey Results In

Snorkel surveys are one of the techniques used to look for juvenile coho salmon.

NPS / Jessica Weinberg McClosky

November 2018 - The juvenile coho population in both Olema and Redwood creeks was smaller than expected given the observed spawning activity during the winter of 2017–2018. One possible reason for lower survival rates was a big storm in early April, during a time when newly emerged coho fry are extremely vulnerable. Although it is not uncommon to get storm events in early April, the magnitude of this storm combined with the later timing of redd deposition likely resulted in substantial coho fry mortality.

Biologists estimate over 1,700 juvenile coho were living in the mainstem of Olema Creek at the time of September surveys. The juvenile population for Redwood Creek is quite a bit larger, with a preliminary estimate of over 4,500 juvenile coho this past August. Read more in the full update or contact Michael Reichmuth for more information.

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