WASHINGTON – A plan to restore salmon runs in California’s Sacramento River could also help revive killer whale populations in Puget Sound, as federal scientists struggle to protect endangered species in a complex ecosystem that stretches along the Pacific Coast from California to Alaska.

Without wild salmon from the Sacramento and American rivers in their diet, the killer whales might face extinction, scientists concluded in a biological opinion that could result in even more severe water restrictions for farmers in the drought-stricken, 400-mile-long Central Valley of California. The valley is the nation’s most productive farm region.

The plan has faced heated criticism from agricultural interests and politicians in California, but environmentalists said it represented a welcome departure by the Obama administration from its predecessor in dealing with Endangered Species Act issues.

The Sacramento plan, they add, represents a sharp contrast to the plan for restoring wild salmon populations on the Columbia and Snake rivers in Washington and Idaho. That plan, written by the Bush administration, essentially concluded that long-term decline in those federally protected runs did not jeopardize the killer whales’ existence, because hatchery fish could make up the difference.

The 85 orcas of the Southern Resident Killer Whale population travel in three pods, spending much of their time roaming the inland waters from the San Juan Islands to south Puget Sound. During the winter they have been found offshore, ranging as far south as Monterey Bay in California and as far north as British Columbia’s Queen Charlotte Islands.

In the mid-1990s, there were nearly 100 orcas in the three Southern Resident pods. The population fell to fewer than 80 by 2001. In 2005, the whales were granted federal protection as an endangered species.

Researches believe the decline has resulted from pollution that could cause immune or reproductive system dysfunction, and from oil spills, noise and other vessel disturbances, along with reduced quantity and quality of prey.

The Sacramento and American river systems combined were once among the top salmon spawning rivers on the West Coast, trailing only the Columbia and Snake.

Prompted by lawsuits, the National Marine Fisheries Service last month published its latest plan for the Sacramento and American rivers’ winter and fall chinook runs. Without further curtailments of water for the federal Central Valley Project and California’s State Water Project, the runs are in danger, the plan said.

The killer whale population is extremely fragile, and scientists said the loss or serious injury to just one could reduce the odds of the pods’ survival.

The scientists also said that hatchery-raised salmon couldn’t be counted on to sustain the killer whales’ survival.

“Healthy wild salmon populations are important to the long-term maintenance of prey populations available to Southern Residents, because it is uncertain whether a hatchery-only stock could be sustained indefinitely,” the scientists said.

Not only are there concerns about long-term funding for the hatcheries, but scientists have questions about whether hatchery fish are as genetically strong.

Meanwhile, the latest plan for the Columbia-Snake wild salmon runs concluded that continued operation of the federal hydroelectric dams on the two rivers was “not likely to adversely effect” the killer whales. Earlier, federal scientists found that “perhaps the single greatest change in food availability for resident killer whales since the late 1800s has been the decline of salmon from the Columbia River basin.”

Though the Columbia-Snake salmon plan acknowledges the potential problems with hatchery fish, it dismisses, at least for now, their impact on killer whale food supplies.

Lynne Barre, a National Marine Fisheries Service scientist in Seattle, helped write both plans and downplays any differences.

“I think we say the same thing,” Barre said.

But environmentalists say the differences are obvious.

“The contrasts are striking,” said Todd True, a lawyer for the Seattle office of Earthjustice, which has challenged the Columbia-Snake plan in a lawsuit in federal court in Portland.

True said the Sacramento salmon plan was a “candid piece of work that had a strong independent review and the absence of political interference.”

The judge in the Portland case has given the Obama administration until Aug. 15 to indicate whether it will stick with the Columbia-Snake salmon plan or offer a new one.

Les Blumenthal: 202-383-0008

lblumenthal@mcclatchydc.com

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