Orcas from L pod, usually seen in state waters, surfaces Sunday near Cypress Point, Calif. Their move may be because of fewer salmon in their Washington feeding area. (NANCY BLACK / MONTEREY BAY WHALE WATCH)
In what a leading orca researcher calls an ominous sign, a group of the killer whales that frequent Puget Sound and nearby waters has turned up feeding off the coast of California for the sixth winter in a row.
L pod, one of three orca families that frequent Washington waters, was spotted Sunday off Monterey Bay.
The fact that the orcas are apparently ranging farther than they once did suggests that Washington's winter stocks of chinook, the orcas' main food, have dropped too low to support them, said Ken Balcomb, a San Juan Island scientist who has studied the orcas since mid-1970s.
Now, if the orcas want to eat, "they've got to go somewhere else," said Balcomb, founder of the Center for Whale Research.
Solving the problem might require a moratorium on salmon fishing for several years, Balcomb wrote in a statement released Monday by the research center.
"The path society is on, according to fisheries experts, is that chinook stocks will be driven to extinction before the end of this century," Balcomb wrote. "We consider that ... worse news for fishermen than a few years of closure to allow stocks the best opportunity to recover."
Before about 2000, L pod and K pod turned up most years during the winter and spring, at least occasionally, in Washington waters, Balcomb said. That suggests they were hanging around in the Pacific, someplace closer than California, he said, because it's doubtful the orcas would make the eight-day trip down to California more than once a year. Bottom line: It looks like the killer whales' behavior has changed.
A recent orca-recovery plan by the National Marine Fisheries Service said until recent years, it was thought the orcas never traveled south of the Columbia River, which historically had numerous salmon.
The report also called reduced chinook numbers here a critical problem for the orcas, which are protected under the Endangered Species Act.
Brad Hanson, a biologist at the fisheries service, said Balcomb's analysis is plausible.
"Oh, certainly. There's been large changes in salmon populations over time," Hanson said. "Obviously the animals are going to respond to that. ... They're highly mobile predators."
As for the orcas' California visits, he said: "We're going to continue to take a long, hard look at this."
Balcomb referred to a controversy over whale-watching boats in Washington waters: "This may solve the 'problem' of whale watching in Washington state. They may just move down there," he said.
"California is being much more proactive in their salmon recovery and setting aside marine reserves (no-fishing zones) and looking forward to recovering salmon, whereas up here fishing interests and commercial interests get first dibs."
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