Lagunitas Creek Spawner Update

by Eric Ettlinger

The holiday season is a tough time to keep up with regular spawner updates, and a lot has been happening in Lagunitas Creek over the last three weeks. Right after my previous update (12/17/12) we were hit by the second large storm of the season, which dropped over seven inches of rain. Stream flows peaked at 1,900 cubic feet per second and within a week Kent Lake began spilling. Flows have remained too high since then to conduct surveys in the main stem of Lagunitas Creek.

A pair of coho salmon spawn in Lagunitas Creek.

On December 27, the day before Kent Lake started to spill, MMWD biologists conducted a survey in the ½-mile reach between the Leo T. Cronin Fish Viewing Area and Peters Dam. They observed 28 coho and 12 new redds. Folks who visited the Fish Viewing Area around that time were lucky enough to witness the best salmon viewing in the last few years.

To date we’ve counted 320 live coho and 170 coho redds, which are the highest counts for early January since 2006. More than half of the redds found so far have been in San Geronimo Creek and Devil’s Gulch, where we’ve documented 49 and 42 coho redds, respectively. By the end of this week we’ll be able to once again survey the main stem of Lagunitas Creek, where we expect to find quite a few more coho redds.

MMWD fisheries intern Ariana Chiapella of the AmeriCorps Watershed Stewards Project prepares to collect tissue samples from a spent female coho salmon.

The timing of spawning this season has been consistent with historical trends (see chart), so within the next three or four weeks coho spawning should essentially be over. But as coho decline, steelhead spawning will ramp up. We observed live steelhead for the first time last week in San Geronimo Creek. Steelhead spawning typically peaks in mid-February and continues through April. This year we’re expecting an above-average steelhead run to return to the Lagunitas Creek Watershed.