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Protecting fish in the Northwest Endangered: Fewer fish at the Ballard Locks in Seattle succeed in returning to spawn in the freshwater of Lake Washington. Hungry California sea lions have contributed to their decline.

SEATTLE — SEATTLE -- It's a place of instinctual attraction for residents of the Northwest, this observation room of the fish ladder at the Ballard Locks. They stop to see an increasingly rare phenomenon: the return of the salmon and steelhead, back from the ocean to spawn in their natal streams.

The underground room is dimly lighted. Behind the submerged windows, the fish are usually milling and shimmying, pointed upstream, waiting their turn to hurl themselves up the concrete-step waterfalls of the fish ladder. The water's traces of cedar and fir needles from the banks of the fish's original streams are calling the fish home to mate and die.

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But sometimes the windows show nothing but empty water. And several months a year something bigger and slower can be seen: California sea lions, chowing down on the fish. In some runs of returning fish, the sea lions devour 60 percent.

Their actions pose questions that people can't easily answer: How many of each species should live on the planet? What should people do when one species threatens another? And what if both species are protected by law?

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Some people in the Northwest blame the sea lions for the declining numbers of fish, while others suggest there is a chain of causes: the sea lions, of course, but also pollution, the decline of natural habitat, and the construction of locks that link the saltwater of Puget Sound with the freshwater of Lake Washington.

If it weren't for the sea lions' carnage, the efforts to control them would be almost funny. Trying to shoo the sea lions away, researchers have used underwater firecrackers. They have tried killer whale songs. They have used rubber-tipped arrows. They have tried nets, traps, dead fish laced with nasty-tasting lithium chloride and outright capture. They have shipped the sea lions south; the mammals returned in a matter of days. Last year five sea lions received a death warrant, but none has yet been shot.

Now enters Fake Willy, a fiberglass killer whale, which a local radio station has proposed submerging to scare away the sea lions. Most of the permits for the 200-pound structure have been granted, but some biologists fear that the mammals will pay no attention it and that the fiberglass whale will just scare the fish.

The steelhead has been hardest hit. It's a seagoing rainbow trout, born in freshwater streams, growing up in the ocean and returning home to spawn. Unlike a salmon, it doesn't necessarily die after mating; some have been known to make the treacherous trip several times.

In the past decade, the population of returning steelhead has fallen from about 3,000 in the early 1980s to 70 in 1994, says Patricia Graesser, spokeswoman for the Army Corps of Engineers, which operates the locks. At least 1,600 are required for a healthy, sustainable fishery. Last winter, only 234 steelhead made it back.

Mike Mahovlich, a fisheries biologist with the Muckleshoot Indian tribe, which historically fished in Lake Washington and co-manages the steelhead run with Washington State, blames the population growth of the sea lion.

In 1972 Congress passed the Marine Mammal Protection Act, outlawing the shooting of California sea lions. Fifteen years ago there were about 13,000 of them; now, after 24 years of protection, the population is estimated to be 200,000.

"When a 1,000-pound animal can get into an enclosed area and just hammer fish, it's sad, but you've got to do something about it," says Mahovlich. "They can just wipe out a run.

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"Just because they have brown eyes and look nice, people think they're tame," he says. "They're not." He advocates shooting the sea lions that eat the most steelhead.

In 1988, 39 sea lions were caught and shipped to southern Washington. Twenty-nine returned, some within four days. The next year, six were taken down to the Channel Islands off Southern California. Three returned.

This year the federal government permitted the state to kill the five sea lions responsible for eating the most fish, a decision now being challenged in court. But Sea World in Orlando stepped in, offering to take the animals. Only three could be caught, one of which then died.

But sea lions aren't the fish's only problem. Some people blame the existence of the locks, which move 80,000 vessels a year. One study found that 50 percent of the year-old sockeye salmon were killed or severely injured passing through the barnacle-encrusted locks on their way to sea. And freshwater spilling over the top of the locks in winter frequently lures returning fish away from the ladder entrance, says Will Anderson, campaign coordinator for the Progressive Animal Welfare Society.

"The Corps of Engineers, they're responsible for this whole mess as far as I'm concerned," Anderson says. "Put them in cages in Sea World. It would be far more effective in protecting salmon."

A large part of the fish's upstream habitat has been destroyed by logging and industrialization -- 30,000 acres of Washington wildlife habitat is lost annually to development. And no one knows for sure how changing conditions in the Pacific Ocean may affect the fish.

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Trout Unlimited, the national organization of fishing enthusiasts, plans to capture about 10 percent of the steelhead run this winter, incubate the eggs, fertilize them and scatter the offspring into tributaries of the lake where steelhead used to live. A new group, People Interested in Saving Steelhead, Sea Lions at the Ballard Locks, hopes to launch Fake Willy sometime this year.

Some people are guardedly optimistic that removing three sea lions last year may have lessened the threat to the fish. "The eating of wild steelhead by sea lions appears to be behavior that's learned, so we're removing some of the old-timers who have been coming back year after year after year," says Tim Waters, spokesman for Washington Department of Fish and Wildlife.

He expects that policy to continue for four to six years. Officials also believe the noise devices near the locks are taking effect, now that the sea lions there have become more scarce.

"From the surface of the water it sounds like an 800-pound cricket down there, chirping once every two seconds, at 120 to 130 decibels underwater," says Brian Gorman, spokesman for the National Marine Fisheries Service.

Perhaps these efforts will preserve the steelhead for future generations. "I have five grandsons who are all fishermen, and I want them to be able to enjoy these fish," says Frank Urabeck of Trout Unlimited. "If nothing else, they should be able to see them at the fish ladder coming through, and see the beauty of these fish that come from salt water into Lake Washington."

Pub Date: 10/16/96


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