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No More Salmon for Pesky Sea Lions

by Susan Gordon
The News Tribune, April 26, 2008

Salmon isn't on the menu at Point Defiance Zoo & Aquarium, but for the next couple of weeks Tacoma's zoo will host a bunch of sea lions with expensive tastes.

The first of what could be many guests arrived Thursday night from the Columbia River below Bonneville Dam, where they and dozens of other male California sea lions have dined on returning runs of spring chinook salmon for the past several years.

The behavior has earned the hungry marine mammals a nuisance reputation among Washington and Oregon fish and wildlife managers, who blame them for eating more than 4 percent of the fish heading upriver.

On Thursday, wildlife officials removed six sea lions from the waters below the dam, about 40 miles east of Portland.

Point Defiance officials offered an animal quarantine area - off-limits to the public - as a temporary hostel for the animals before they're returned to the Columbia or shipped to other zoos.

The Tacoma zoo played a similar role 12 years ago, when a different group of hungry sea lions was removed from Seattle's Ballard Locks, said John Rupp, aquatic animal curator.

Of the six trucked to the zoo Thursday, three were to be branded for future identification and returned to the river's mouth Friday evening, a state biologist said.

The other three are to spend the next few days in Tacoma before they're packed in special shipping crates and flown - accompanied by trained handlers - to permanent homes elsewhere.

"We have a possibility of relocating and finding homes for 19," said Rupp, who helped arrange some of the adoptions.

Among future homes are zoos in St. Louis and Brownsville, Texas, plus Sea World locations in Texas, Florida and California, he said.

While the captives wait for plane rides, they'll be penned in a 30-by-30-foot fenced enclosure within the zoo's animal rescue and rehabilitation center, Rupp said. There's no pool, but a spray of water dampens the yard, which also offers shade.

As for the menu, Point Defiance will give the sea lions its usual marine mammal mix: mackerel, capelin, smelt and herring, Rupp said. But no salmon.

"That was a luxury they had at the dam," he said with a chuckle.

Four Sea World handlers will care for the creatures during their stay at Point Defiance. Each receiving zoo or aquarium is paying travel costs, Rupp said.

"Our involvement and expense is minimal," he added.

At Bonneville, trapping is to resume Monday. Action on Thursday followed a Wednesday court decision that prohibited killing but allowed removal of specific troublemakers.

Among those confined at Point Defiance on Friday was C-319. The 1,100-pound mammoth is among 15 or 20 sea lions drawn each spring to the fish-filled waters below the dam, said Steve Jeffries, a state Department of Fish and Wildlife marine mammal biologist.

"He's one of the worst salmon-killers at Bonneville," Jeffries said. "He makes his living killing spring chinook."

For example, during a single two-month period last year, C-319 gained 500 pounds, Jeffries said. Biologists know this because they've trapped and weighed the beast several times.

To survive, sea lions must consume food equal to 8 percent of their weight daily, Jeffries said. So if a sea lion hanging out below Bonneville weighs 1,000 pounds, it's probably eating 80 pounds of chinook daily, Jeffries said.

Ordinarily, sea lions are protected by federal law. But in 2006, Washington, Oregon and Idaho officials asked federal officials for permission to destroy certain sea lions below Bonneville because they eat so many imperiled salmon and steelhead.

In March, federal officials agreed to permit killing as many as 85 sea lions annually as long as wildlife officials first tried to place them in zoos. On Wednesday, a federal appeals court at least temporarily ruled out extermination.

At Point Defiance on Friday, wildlife veterinarians and biologists from two states examined each of the big beasts to make sure they were free of disease so they don't carry germs to other zoos or aquariums.

"In general, these animals are healthy," Jeffries said. "They wouldn't be at Bonneville actively foraging if they weren't."

When it comes to handling animals as big as sea lions, even cursory physicals are difficult. It took six people to weigh and measure them, draw blood and take urine for laboratory tests, Jeffries said.

To deliver the sea lions to Tacoma, biologists used a specially modified horse trailer, big enough to haul six animals at once. Zoo workers used a forklift to remove each sea lion from the trailer, in which they had spent the night.

Confinement didn't appear to bother them.

"They were just sleeping when I came in," said Rupp, who got his first look at the sea lions Friday morning.

Jeffries, who noticed the same behavior, wasn't surprised.

"They do two things," he said. "They kill salmon and they sleep."

Susan Gordon
No More Salmon for Pesky Sea Lions
The News Tribune, April 26, 2008

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