Mary Callahan, THE PRESS DEMOCRAT
The Russian River’s once celebrated salmon populations have long been imperiled by logging, development, gravel mining and other human activities that have eliminated flood plains, channelized river and stream flows, and limited the woody debris and shade that keeps the water cool enough for young fish to survive.
More intense and frequent droughts have further eroded conditions, not just for the coho, but for steelhead and chinook salmon, both listed as threatened under the federal Endangered Species Act.
They were once abundant in the cold, clear water of North Bay creeks and streams. Now, the survival of coho salmon is being challenged like never before.
The coho has a three-year life cycle that takes it from stream to ocean and back to stream to spawn the next generation.
But the changing climate now threatens the species at every life stage, raising new questions about their recovery.
It’s not just a species at stake. At risk is the very resilience of the forest and watershed that evolved around them, fed by marine nutrients brought upstream and deposited inland by adult spawners that, after reproducing, die and decompose.
“Salmon are a keystone species, which means they perform a really important ecosystem service,” said Sarah Nossaman Pierce, a California Sea Grant fisheries biologist with the Russian River Monitoring Program. “Salmon and steelhead (trout) bring marine-based nutrients into the system and essentially feed the forest, plants, birds and wildlife.”
The challenge, she said, is “ecosystem resilience”
“People say, ‘Why do you care about the salmon?’ Unfortunately, if they can’t survive, human beings aren’t far behind,” she said.