Genetic study may help state's salmon population

California salmon fishermen might benefit from a $2 million study using genetics and global positioning systems to link the ocean location where fish are caught with the rivers from which they were spawned.

Gathering such information one day might better protect the state’s weaker salmon stocks, the fish from rivers where regulators predict relatively low abundance in a particular season.

Through the use of genetic testing and GPS tracking, the theory is fishermen could be directed to better avoid those restricted salmon. In return, at times they might receive more access to fish from rivers with larger spawning runs.

“That’s exactly what the Canadians are doing with their chinook salmon fishery off the coast of British Columbia,” said John Carlos Garza, a research geneticist based in Santa Cruz with the National Marine Fisheries Service.

The result, Garza said, is Canadian fisherman have “pretty dramatically” reduced their catch from struggling salmon runs while pursuing larger catches from more abundant rivers.

A smaller scale study last year in California produced noteworthy results, which Garza shared last week at a salmon meeting in Santa Rosa.

In the region off Mendocino County between Point Arena and Shelter Cove, 42 percent of the study’s catch in April came from Central Valley rivers. Of the rest, 21 percent came from the Klamath, 20 percent from Oregon’s Rogue and 7 percent from other North Coast rivers, predominantly the Eel and the Russian.

In contrast, 60 percent of the fish caught between San Francisco Bay and Point Arena in July came from Central Valley rivers.

Garza said the data suggests an abnormally low abundance of Sacramento River salmon last year.

In April 2006, a study using recreational catches off Monterey showed that 92 percent of the fish came from the Central Valley system. A year later that figure had dropped to 71 percent.

This Friday in Sacramento, the Pacific Fishery Management Council will select three options for the coming season.

Many fishermen predict one option will be a statewide ban on fishing due to poor returns predicted for the Sacramento River, normally the state’s most productive river. Such a ban would rule out the research this season, those involved said.

In April, the council will recommend season rules to the U.S. Commerce Department, which oversees the salmon fishery. The commercial season normally begins May 1.

Currently salmon regulators try to manage the fishery by relying on historic catch data, which is limited because only a fraction of the caught fish are tagged by a hatchery and, thus, can be linked to a particular river. Catch location also is much less precise than what can be recorded with the study’s approach using GPS tracking.

Oregon and California are working together on the genetic study, funded by both federal fisheries and disaster aid.

Fishermen could receive about $1 million to take part in the study, said David Goldenberg, chief executive officer of the California Salmon Council, a state-created marketing group based in Sacramento.

The fishermen would be paid to land the fish, use a GPS unit to pinpoint the catch location and take a small clip from a fin to be analyzed later by scientist. The fish then might be harvested or returned to the ocean.

Chuck Wise, a Bodega Bay fisherman and the outgoing president of the Pacific Coast Federation of Fishermen’s Associations, said the study would prove valuable if such a program some day allowed regulators to open or close fishing grounds in the midst of a salmon season.

“Then we could work on the stronger stocks,” Wise said.

You can reach Staff Writer Robert Digitale at 521-5285 or robert.digitale@pressdemocrat.com.