Rain spikes Marin’s salmon, otter viewing
From our perch above Devil’s Gulch Creek, a small stream in Marin County, it felt like we were glimpsing a secret world.
At the bottom of a ravine edged by redwoods, we sighted a pair of 2-footlong endangered coho salmon, bright crimson in their spawning colors, one digging a nest while the other waited a few feet away.
It’s nature’s way, when the season’s first rains recharge Lagunitas Creek and its tributaries, of drawing in coho salmon to spawn. Watching them has become the Bay Area’s newest outdoor spectator sport. River otters, which try to eat the salmon, often are sighted as well.
The best sites to see the coho salmon are in Lagunitas Creek at Samuel P. Taylor State Park, the nearby Leo T. Cronin Fish Viewing Area, Shafter Bridge and the Ink Wells, Devil’s Gulch, Roy’s Pool near San Geronimo, and downstream of the Peters Dam below Kent Lake. Access is from Sir Francis Drake Boulevard, the major artery that provides access from Fairfax to west Marin. On my best day, I saw 40 jumping salmon at the Ink Wells, as well as a family of sea otters.
More than 11 inches of rain has fallen on the flank of Mount Tamalpais, with more forecast for Friday and Sunday. The rain has jump-started the annual migratory run of coho salmon and, with it, the chance to see them do their thing.
Guided trips offer best chance
On Saturday in Samuel P. Taylor State Park, naturalist Catie Clune positioned a group at an overlook of Lagunitas Creek: Those folks were rewarded when two coho salmon spawned right in front of them. They later saw another dozen staging nearby.
“We saw one pair actively spawning in the main stem of Lagunitas Creek,” Clune said. “She was digging and a large male was actively guarding her from other males. We continued down the stream to a holding pool that is deep enough for fish to wait it out until the next big rain. We could see over a dozen fish.”
Clune said this weekend’s forecast rain would trigger movement of coho salmon all through the river system.
Guided trips provide the best chance of sighting the coho. Creekwalk Tours are available through the group SPAWN, which operates under the organization Turtle Island Restoration Network. Spaces are $15 with advance registration and space for 20, and take place on weekends through Jan. 12.
Do not arrive for a creek walk without advance registration. Last winter, after a one-line note in a column in The Chronicle, 80 people arrived for a guided walk. If you want the sure thing with a guide, sign up first.
2 feet of crimson
If you haven’t seen a coho salmon, the sight of one in a stream — often the size of a trout creek — can blow your lid off. The fish average about 2 feet long, and in spawning colors, the males turn crimson red. When your timing is right, you can see them jumping through small waterfalls, such as at the Ink Wells, and building nests in shallow creeks.
They live their adult lives in the ocean, where they are chrome-bright silver. As late fall arrives, they migrate from across the sea and into Tomales Bay. When the rains spike Lagunitas Creek, the salmon launch up past Whitehouse Pool and into Lagunitas Creek and its tributaries.
On peak weekends, hundreds of people can travel to Marin in hopes of sighting the coho, and over the course of the winter season, thousands. Watching them from viewing stations, bridges and bluffs overlooking streams has no effect on the behavior of the fish, said Rebekah Staub, who works on outreach for stream tours. As a protected species, fishing for them has long been banned. In the ocean, if caught by accident, a rare event, they must be released immediately without touching the fish (easily accomplished with required barbless hooks).
About 500 adult coho salmon usually arrive in Lagunitas Creek from mid-December through mid-January. They produce about 10,000 smolt that venture through Tomales Bay to the ocean. Over the years, the numbers cycle up and down according to stream conditions. In drought years, the flow of fish can be reduced to a trickle that resembles the creek. This winter is starting out like there will be a flood of fish.
In late December, steelhead then follow. About 25 streams across the Bay Area can draw in steelhead when water flows are sufficient. They include Pescadero and San Gregorio creeks on the San Mateo coast, San Francisquito Creek in Palo Alto, Alameda Creek from Newark to Niles to Sunol, the Napa River and Walnut Creek.