Written by: Eric Ettlinger, Aquatic Ecologist
The first big storm of the season arrived on November 28, just as I was sending out the last spawner update. Lagunitas Creek flows increased to over 200 cubic feet per second, prompting a surge of coho salmon to swim upstream. Surveys last week found three coho in Devil’s Gulch, 34 coho in San Geronimo Creek, and 52 coho in Lagunitas Creek.
Most of these coho congregated in deep pools to await the next rain and higher stream flows. A school of 32 coho is currently holding in the “Swimming Hole” in Samuel P. Taylor State Park, although they’re very difficult to see. Getting a precise count required lowering a camera on a rope and then post-processing the murky footage. That effort was worth it, however, because among the coho we observed one chum salmon and two adult steelhead. We don’t typically see steelhead until January, and these are the earliest steelhead seen since 2005.
Rain is forecast for Sunday, which will hopefully raise stream flows enough to get large numbers of coho moving and spawning. Monday may be a good day to look for coho jumping through the Inkwells into San Geronimo Creek.
Below is a table of spawner observations to date. The steelhead seen this week bring our salmonid species total to five, for the second year in a row. We’ll conduct one more survey tomorrow, which will increase this week’s coho count, and possibly the counts of Chinook, chum, and maybe even steelhead.