[3] States, Politicians Gang Up On Sea Lions

After several years of stepping up harassment of marine mammals feasting on ESA-listed spring chinook at Bonneville Dam, Washington and Oregon have finally thrown in the towel. Both states have made formal applications to the federal government for the authority to kill the pesky sea lions, which are protected under the Marine Mammal Protection Act.

Last year, marine mammals chewed their way through about 3 percent of the spring run and were cavorting in Bonneville's fish ladder, much to the pleasure of TV newspeople, despite heroic efforts by the Corps of Engineers to outsmart the hungry critters. The Corps put up bars, shot firecrackers, and even tried "underwater acoustic deterrents" to keep the hungry pinnipeds away from the migrating fish.

Marine mammal numbers on the West Coast have tripled since falling under the protection of the 1972 Marine Mammal Act. The California sea lion population is now estimated at about 250,000. Steller's sea lions make up another 31,000, and the harbor seal population in Oregon and Washington adds up to about 25,000 more pinnipeds.

Biologists say the predation problem at the dam has increased more than sevenfold in recent years. Meanwhile, another thousand or so sea lions cruise the lower river every spring, eating an unknown amount of salmon and sturgeon. Biologists say sea lions eat about six salmon a day if fish are available.

But the process to get legal authority to kill a few sea lions may take years, and must include a review by a task force represented by states, feds, tribes, scientists, and conservation and fishing groups

That lengthy possibility propelled three Northwest politicians to introduce a bill in October that would allow the Secretary of Commerce to issue permits to allow the "lethal taking" of up to 10 sea lions by next spring if other measures don't work.

Washington's Doc Hastings (R), Brian Baird (D), and Norm Dicks (D) crafted the bill in such a way that up to six permits could be issued. The bill also says that the total number of sea lions that might be killed could not exceed one percent of "the annual potential biological removal level of California sea lions."

Baird said the bill is a tool to use after all other options have been exhausted, "and it will send a strong message that the all-you-can-eat salmon buffet at the Bonneville Dam is closed."

The states' application calls for removing a limited number of California sea lions within six miles of the dam, along with other marked animals that have been seen there eating salmon.

"Lethal removal is a management tool we prefer not to use, but one that may be necessary to restore balance to the Columbia River ecosystem where threatened and endangered stocks of salmon and steelhead are being preyed on by a healthy and growing population of California sea lions," said Guy Norman of WDFW's southwest regional office.

Last month, at the Corps of Engineers annual research review in Portland, scientists reported on studies undertaken in recent years dealing with the sea lion problem.

In one study, radio-tagged salmon were tracked to see if hazing activities designed to deter the marine mammals would have adverse affects on fish passage. Salmon actually showed a proclivity for entering fishways while hazing was going on and while the "acoustic deterrent device" was in operation, though the researchers said it was not a statistically significant difference.

This year, sea lions saw both fireworks and rubber bullets headed their way, along with a 205-decibel 15 kHz frequency sound at fishway entrances. Other agencies manned boats to haze the mammals up close.

But overall, this year's hazing efforts kept the predation level similar to that observed in 2005 when 3.4 percent of the run was estimated to have been intercepted by the salmon-loving sea lions, though down a bit to 2.8 percent.

The Corps said about 72 California sea lions, 10 Steller's sea lions and 3 harbor seals were documented in 2006. With an average of about 27 marine mammals around the dam on any given day, the researchers found that hazing didn't make any difference in those numbers, but the grating installed at fishways kept most sea lions from entering.

Their conclusion so far? Non-lethal deterrence has proved ineffective in reducing predation, but more intense hazing efforts may keep sea lions away from fishway entrances.

Last spring, about 96,000 spring chinook were counted at Bonneville Dam. Close to 3,000 of them were estimated to have been eaten by sea lions. About 8,800 upriver springers were caught in tribal fisheries, and about 1,900 in non-Indian sport and commercial fisheries. -B. R.

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