From the outside, the sprawling new red shed at the base of Warm Springs Dam, in Sonoma, Calif., looks suited to cows, pigs and other farm animals. But a peek inside reveals several dozen above-ground tanks, resembling water troughs, and pools, resembling Doughboy Pools. In total, the tanks and pools hold roughly 200,000 young coho salmon, ranging in size from smaller than a pinky finger, to the length of a forearm.
This new building officially opened with a ribbon cutting ceremony yesterday, and will house the 10-year-old Russian River Coho Salmon Captive Broodstock Program, which aims to bring Central Coast coho back from the brink of extinction.
“We started this program just in the nick of time,” said Ben White, a biologist with the U.S. Army Corps of Engineers, who oversees daily operations at the hatchery. Prior to the new building, the pools for raising the fish were housed under nets to fend off birds and raccoons. The new building offers the fish better protection, and the salmon's caretakers shelter from the elements. “Both humans and fish,” White says, “will be happier and safer.”
It is loss of habitat, however, and not roving raccoons, that primarily threatens these fish. Without this program, coho in the Russian River would likely be extinct. Today, White and others are hopeful that a sustainable, wild breeding population can re-establish.
The coho of California’s Central Coast are traditionally a reproductively isolated group, extending roughly from Humboldt County in the north to Santa Cruz in the south. The group is distinct enough, biologists believe, to warrant classification as an evolutionarily significant unit, allowing them to be listed for protection under the Endangered Species Act.
Historically, the Russian River, which flows southward through Mendocino and Sonoma Counties, was the most
significant breeding and feeding ground for these fish. As river conditions changed, due to development, agriculture and dams, including temporary seasonal (or "summer") dams, water levels dropped, average temperatures rose and the river muddied.
Biologists noticed a precipitous decline among coho in the late 1990s. Numbers dwindled so drastically that in 2001 biologists from the U.S. Army Corps of Engineers and other state and federal agencies staged a rescue operation -- capturing what wild fish they could find to begin a captive breeding program.
The Russian River Coho Salmon Captive Broodstock Program has released hatchery-raised coho since 2004. But, until this year, return rates have been poor. The fish are marked with small tags, roughly the size of a grain of rice, inserted into their abdomen, that trigger sensors when they return at the end of their life cycle. The winter of 2009 - 10 was the first year that more than 20 fish were observed returning to the Russian River. This winter, nearly 200 were seen, of the nearly 170,00 released. (Researchers estimate three to four times that number actually came back.) While scientists would like to see far more than that -- around 3,000 would be great, they say -- it’s a good start.
Hatchery programs are frequently criticized by environmental groups for artificially boosting fish numbers and masking the real cause of fish decline -- loss of habitat. The truth is, no matter how well housed the breeding program, there is no substitution for good rivers.
Given the dire circumstances, however, a breeding program for the wild population is the best option. “It’s a desperate measure," says Bakke, “a sign you’re at the end of your string.”
The fact is there would be no coho left in the river without this program, says DuBay. But she admits, “The long-term survival of the fish will come only from improving the health of the river.” Later this summer, the agency will begin a project to restore 6 miles of habitat along the river. A drop in the proverbial bucket, but a start.
“These fish indicate the health of the whole ecosystem,” DuBay says. “Helping them helps other fish, and other plants and animals. Plus, you want your children and grandchildren to see these fish. They’re worth saving.”
Danielle Venton is a former High Country News intern and reporter for KRCB in Sonoma County, California.
Image(s): 1) Coho salmon/Alaska Department of Fish and Game; 2) Rep. Mike Thompson at the ribbon-cutting ceremony of the new building housing the Russian River Coho Salmon Captive Broodstock Program/Danielle Venton; 3) A biologists removes covers from a juvenile coho tank at the Broodstock Program/Danielle Venton.