SEE ALSO: Can Salmon Farmers Clean up Their Act?

King Salmon in Search of a Future

OF THE FIVE SALMON species that occur in California, the king (chinook) is the most esteemed. It can weigh up to 127 pounds. Today's largest king salmon runs occur in the Sacramento-San Joaquin River system, four times a year: in winter, spring, early fall, and late fall. The spawning population of the winter run has declined by 99 percent in the past 25 years, and the National Marine Fisheries Service has listed it as endangered. The spring run is a candidate for similar listing.

The causes of the salmon's imperiled condition are obvious. Only five percent of the Sacramento River basin's historic salmon habitat remains, 300 of 6,000 miles. Dams block the fish from ancestral spawning grounds, river water is diverted for agriculture and urban development, sediment from road cuts and from logged and urbanized hillsides muddies the water. The early fall run is also vulnerable because it depends in great part on hatchery-produced juvenile fish from captive salmon broodstock, which are more susceptible than wild stock to genetic inbreeding and infectious disease outbreaks.

Similar problems have depleted salmon runs on the Klamath and Smith Rivers and on smaller coastal rivers, including the Redwood, Mad, and Mattole.

State and federal resource agencies are funding efforts to restore spawning habitat, to screen irrigation diversion outlets that kill young salmon, and to remove derelict dams. In July of this year, Secretary of the Interior Bruce Babbitt presided over the removal of four small, outmoded irrigation dams on Butte Creek, a tributary of the Sacramento River, reopening eight miles of prime spawning habitat for salmon. In June, the federal Ninth Circuit Court of Appeal ruled that state and federal agencies must include provisions to protect salmon runs in renewing water contracts.

No significant action has been taken, however, to stop the destruction caused by the pumps near Tracy, which withdraw water from the Sacramento-San Joaquin Delta for agricultural use in the Central Valley and urban use in southern California. The pumping system, run by federal and state water agencies, is a "black hole" for fish, says Zeke Grader, executive director of the Pacific Coast Federation of Fishermen's Associations. The massive withdrawals degrade water quality and reduce food supplies for fish. The huge pumps entrain and kill juvenile fish. Changes in the amount and timing of the withdrawals could make the pumping system more fish-friendly and expedite salmon recovery. However, proposals for these changes are enmeshed in a legislative stalemate over how to allocate water supplies.    --WM