Juvenile Monitoring

Summer 2021 salmon and steelhead snorkel counts

California Sea Grant and Sonoma Water biologists conduct snorkel surveys each summer in order to document the presence, distribution and minimum count of young-of-the-year (yoy) salmon and steelhead. These fish were spawned and hatched the previous winter or spring. Snorkel surveys are conducted in every second pool and expanded counts are generated by doubling the observed count, to get a rough estimate. 

In 2021, wild coho yoy were observed in 17 of the 43 streams surveyed, with an expanded count of 5,262. This is 52% of the five-year average.

Steelhead yoy were seen in 27 of the 43 surveyed streams and the expanded count was 12,717--just 25% of the five-year average. 

See the Summer Monitoring Reports for a detailed overview of snorkel survey methods and outcomes for each year. *Tip: Table 1 shows how many fish we saw in each stream.

juvenile coho salmon
Wild juvenile coho salmon on Felta Creek


California Sea Grant biologist searches for juvenile fish