Rains make way for Lagunitas Creek coho return

12/04/2019

After a dry fall, the first storms of the winter kicked off the annual migration of coho salmon from the Pacific Ocean to the streams where they spawn. Over 10 inches of rain fell on Lake Lagunitas last week—slicking roads, knocking out power and felling branches. Streamflows are now high enough to allow endangered central California coast coho to migrate through Lagunitas Creek and into tributaries, said Eric Ettlinger, an aquatic ecologist for the Marin Municipal Water District. Already, other species have been spotted. The first species to arrive was the pink salmon, which create distinctively small gravel nests, or redds. Ten of those nests have been observed since September. The second species to arrive—in October—was the chum salmon; only two have been seen, but the species is rare in the region. Chinook salmon arrived in November, and so far, biologist have observed 41 of them and 13 of their redds. But the main attraction, due to the fishes’ bright colors and their abundance compared to other species—is the coho salmon run. “Flows are currently too high and muddy to see the fish, but over the next few days [coho] will hopefully be visible migrating, jumping, fighting and spawning throughout the watershed,” Mr. Ettlinger wrote for the water district’s blog. Biologists from the district, the National Park Service, the Watershed Stewards Program and the California Department of Fish and Wildlife will count the coho, whose run is expected to be below average, based on a hypothesis that ties the number of fish returning to the number of smolts leaving 18 months ago. Survival in the ocean is also a key factor. Last year’s run was the largest in 12 years, with over 700 adults and 300 redds. But even with a banner year last winter, the coho still fell short of the watershed target of 2,600 adults set by the National Oceanic and Atmospheric Administration. If that number is reached consistently for three years, and targets were also hit in other Northern California streams, the species would be considered recovered. Turtle Island Restoration Network is celebrating the annual return with walking tours along the creek. “This is one of Marin’s most amazing wildlife spectacles, and no nature enthusiast should miss it,” said Todd Steiner, the group’s executive director. Tours start at 10 a.m. every Saturday in Samuel P. Taylor State Park. For more information and advance tickets, visit seaturtles.org/creekwalk.