Baby salmon trickle back to Russian River waterways after a long absence
After an absence of more than a decade, a trickle of salmon are finally finding their way back to Sonoma County streams, thanks to private landowners and a coalition of conservationists.
Roughly 22 million years ago, the fish we know as salmon evolved the complicated biology they needed to commute between inland freshwater streams and the open salty ocean. Thus began one of the most remarkable life cycle journeys known on the planet.
Two million years ago, on the ancient California coastline, the salmon would have found a perfect cold and clear waterway emptying into the Pacific near the mouth of today's Russian River. Running a hundred miles back among high ridges and dense redwood forest, its widely branching network of creeks and tributaries made ideal habitat for the spawning fish and its young.
And that paleo-Russian River has been the salmon's home ever since.
So it came as a shock in 2001 when naturalists, fishermen and the community discovered that the number of coho salmon counted returning to the Russian River, once totaling 100,000, had dwindled to only 5.
It was found that throughout the watershed, the populations had crashed, and the salmon were disappearing, stream by stream. By 2004, only 3 of 39 tributaries and creeks in the entire watershed held any coho at all.
This past December, in a quiet event out of public view, red-flushed mature coho salmon were once again found spawning in the tree-shaded upper reaches of Mill Creek west of Healdsburg, where they had been virtually absent for decades.
That small, exciting homecoming was no accident. It came after more than 10 years of study and planning, captive breeding and painstaking stream rehabilitation by a smorgasbord of local, state, and federal agencies, private groups, academic institutions, community coalitions and concerned individuals.
And the vital key and the unsung heroes of the salmon rescue, according to those involved, are some of the private landowners whose property surrounds Mill Creek. In a scene that's playing out along hundreds of miles of streams and creeks across Sonoma County, individual landowners are proving to be the crucial link in bringing the salmon home again.
Tracking the salmon
Everyone involved with salmon rescue in Sonoma County knows Mariska Obedzinski, because it's her job to count the salmon. A fisheries biologist, Obedzinski is the coho monitoring coordinator for UC Sea Grant. Counting, for Obedzinski and team members Nick Bauer and Zac Reinstein, involves daily checks of underwater traps during the spring, snorkeling through chains of creekbed pools during the summer, and monitoring remote sensors to spot salmon carrying tiny implanted tracking devices.
Before the coho can be upgraded from the red-line federal “endangered” classification, Obedzinski must find 10,100 salmon in the watershed for three consecutive years. This past January, the estimate was 456. That makes every single salmon spawning again in prime habitat like Mill Creek vitally important.
Challenges for the coho
Mill Creek collects water from mountains in one of the wettest spots in Sonoma County, near Venado. Then it burbles and winds for 15 miles through wooded mountain canyons and second growth redwoods, before entering Dry Creek about a mile from the Russian River, and 35 miles from the sea.
Experts consider the upper reaches of Mill Creek to have the perfect mix of what coho need to survive: steady flowing water, woody cover, cool pools and clean gravel beds for salmon eggs. Water flow is especially critical: after hatching, juvenile coho spend an entire year or more in the stream before heading to the sea. “Their biggest challenge,” Obedzinski says, “is surviving that first summer, because streams begin to dwindle and pools shrink as soon as rains end in February or March.”
Unfortunately, civilization has not been kind to the salmon's streams. Today, about 95 percent of Sonoma County's million acres are privately owned, and that means to survive the salmon must compete for water with the residents, ranches, vineyards, dairies and farms along their streams.
The other challenge coho face is the marathon swim home. After living two or three years in the Pacific Ocean, male and female salmon will successfully navigate upstream, through strong winter currents and rock-strewn mountain canyons, swimming to elevations of more than 1,500 feet, to find their ancestral stream and each other, to start the next generation.
Unless, of course, they meet a dam.
And that was the problem with Mill Creek: about a mile up, there was a dam. First built in the early 1900s in a narrow steep-sided canyon, it sits on four adjoining private properties, and is still being used as the source of drinking water for two creekside homes.