the film

Aggressive Sea Lion Hazing
to Begin at Bonneville Dam

by Vince Patton, February 27, 2007

Federal and state biologists are preparing for the earliest and most aggressive hazing program ever to attempt to drive salmon hungry sea lions away from Bonneville Dam.

Unlike last year's hazing which staggered on for four days followed by four days off, this year the harassment will blitz the sea lions from dawn to dusk, seven days a week from March 1 through the end of May. The only breaks will come at night.

"It's a maximum effort," says Army Corps of Engineers biologist Robert Stansell. "We're trying all the non lethal tools we have in our hands at this point."

The Corps will harass sea lions with noisemakers shot over their heads from the decks of the dam, with far more latitude than was allowed last year.

Stansell says, "This time they'll have full capability to haze and harass any sea lion they see and chase it down to where the boats can catch them."

From boats, agents from the departments of fish & wildlife for Oregon & Washington will be equipped to shoot at the marine mammals with rubber shot gun shells.

Seal bombs, the waterproof equivalent of 1/4 of a stick of dynamite will also be used until fish arrive in large numbers.

Biologists are predicting a lower spring salmon run this year. That makes hungry sea lions an even greater problem given their history of eating an estimated 3,000 salmon last year at the dam.

Spotters at the dam have counted seven stellar sea lions at the dam since early January, which is normal for that breed. What's unique is the early arrival of seven California sea lions at the dam a month earlier than ever spotted before. Stansell says, "They're just going to hang around and wait for the chinook run to show up."

The goal of the super aggressive hazing is to drive the sea lions away from the dam far enough for boats to then cut in and drive the animals even farther downstream.

One other new tool is also in place. A floating platform now sits anchored next to a concrete berm popular with sea lions as a place to haul out of the water. The platform is actually a trap. If they're lucky, biologists will be able to capture problem sea lions and cart them back to the Pacific Ocean for release.

The states and tribes have urged the federal government to approve the killing of about 80 problem sea lions at the dam. That process could take years. In the mean time, all agencies must prove they have tried every other means possible.

Despite the failure of last year's hazing, Stansell expresses confidence. "I think we're going to be able to chase a number of animals out of here," he says. But he also concedes there are die hard animals who know an easy feast when they see it which will be very hard to chase away.

Officials have not broken down the costs of the hazing program by itself. However the National Ocean & Atmospheric Administration says hazing combined with sea lion branding is estimated to cost $300,000.

"If it's successful, I don't know if we could ever keep it up financially," says Stansell, "but we're at least giving it a try."

Vince Patton
Aggressive Sea Lion Hazing to Begin at Bonneville Dam, February 27, 2007

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