Cooling rivers in warmer regions may save salmon
Posted on April 29th, 2008Climatewire: The best hope for cold-water chinook salmon to survive global warming may be near sweltering Fresno, Calif., in the San Joaquin River, experts say — where salmon have been extinct for 60 years.
A half-billion-dollar project to restore fish runs in the San Joaquin is set to begin in 18 months. Fishery experts say salmon living in the river would be able to withstand the effects of climate change better than salmon in cooler places like Northern California.
The reason: The highest part of the High Sierra would continue to provide the cold water that the salmon must have to survive in the San Joaquin River. Northern California has the lower end of the Sierra and, scientists say, will eventually lose much of its snowpack and much of its cold water.
“The restored San Joaquin may be an important place for the survival of salmon in the next century,” said fishery biologist Peter Moyle of the University of California at Davis.
A worldwide panel of experts reported last year that about 40 percent of the salmon habitat in the Pacific Northwest could be lost because of climate change.
But area farmers, forced by legal settlement to give up irrigation water for the project, are skeptical.
“I’m very concerned about investing in bringing back these fish if we’re just going to lose them later on,” said farmer Kole Upton.
Farmers agreed in 2006 to cooperate in the restoration only because they were losing a marathon legal battle over the issue. They remain worried about the $2.5 billion agriculture economy that the river helped to create on the valley’s east side.
Now, they are committed to giving up an average of 19 percent of their water annually to reconnect the San Joaquin with the Sacramento-San Joaquin River Delta (Mark Grossi, Fresno Bee, April 27). – RB