Salmon-Eating Sea Lions Facing Death by Lethal Injection
by Jen Matteis
They’re a welcome attraction at Sea Lions Caves, San Francisco’s Pier 39, and other sites on the West Coast, but 40 miles east of Portland, wildlife officials are killing California sea lions by lethal injection. The crime? Eating endangered Chinook salmon and steelhead trout at the Bonneville Dam on the Columbia River.
California sea lions congregate at the dam’s fish ladders during the salmon runs, from January through May. The Marine Mammal Protection Act typically protects sea lions–except when they threaten an endangered species.
So far this month, four have been killed; 92 are on the list for possible removal. The sea lions on the list fulfill certain criteria: they are branded, which makes them easy to identify; they were seen eating salmon or steelhead near the dam; they were seen at the dam for a total of five days, which can accrue over a period of years; and they haven’t responded to non-lethal hazing, or the use of explosives to scare them away.
According to Rick Hargrave, spokeperson for the Oregon Department of Fish and Wildlife, killing sea lions isn’t the preferred option, but hazing became ineffective.
“It’s not our first option–you don’t want to get to the point where you’re putting down one species for the recovery of another,” he said.
Since the spring of 2008, wildlife officials have euthanized 25 sea lions. The sea lions are trapped in floating cages that attract their natural tendency to haul their bodies out of the water.
“If it’s an animal that’s on the list for removal, the door will be closed. They transfer the sea lions from that larger cage to a smaller transfer cage, and then they barge them around to a smaller area at Bonneville. Vets come in and take a look at the animal and take notes, then the lethal injection process begins and they put the animal down,” Hargrave said.
Five additional sea lions died in captivity, and 10 were relocated to zoos and aquariums. The Shedd Aquarium in Chicago has said it will take one more sea lion. It already houses two “problem animals” from the Bonneville Dam, Biff and Otis–the latter was about 250 pounds overweight on his diet of endangered Chinook salmon.
“Otis and Biff were among a group of sea lions who had found an easy meal of Chinook salmon along the fish ladders of the Bonneville Dam,” reports the Shedd Aquarium’s website. “They couldn’t stay away from the unintended seafood bar.”
The easy pickings at the fish ladder combined with less fish in the ocean may cause sea lions to congregate at the dam. According to Hargrave, it’s unclear whether traveling 140 miles inland to the dam constitutes natural behavior.
“There’s two sides of the fence on this; some folks say this is perfectly natural, it’s been going on for thousands of years. We’re saying this is more of a recent phenomenon that has occurred within the last 10 years or so,” he said. “When you have a small run and this level of predation occurs, then you see this dramatic impact on the fish. That’s why we need the authority to stop the sea lion predation, recognizing that these more recent robust runs of salmon might not always occur.”
The Humane Society of the United States has filed several lawsuits, and is currently seeking an injunction to stop the killings. A judge overruled one lawsuit last month, but did institute a cap of 30 sea lions maximum that could be killed in 2012, along with a ban on the use of firearms.
According to its website, the Humane Society believes that the sea lions have a negligible impact on salmon compared to fishing. Fishermen are permitted up to 17 percent of the Chinook salmon, although that includes fish raised in hatcheries for the purpose of commercial and sport fishing. It’s estimated that sea lions take between one and four percent. However, Hargrave noted that the percent taken by sea lions could be as high as 18 percent, as the estimate doesn’t take into consideration predation that occurs underwater or during the night. For wild endangered fish, the limit is two percent mortality on the run size. Steller sea lions also congregate at the dam and present a major threat to sturgeon, but they are protected by their own endangered status.
The dam itself is another obvious fish-killer. “The National Marine Fisheries Service estimates the Federal Columbia River Power System kills 16.8 percent of adult Snake River Basin steelhead and 59.9 percent of juveniles,” reports the Humane Society website.
Both sides are united in a goal of having healthy populations of salmon and steelhead–whether the “problem animal” is man or sea lions depends on the perspective.
“Passionate people on all sides agree that we want healthy populations,” said Hargrave. “There’s typically professional disagreement on how we get there.”
For more information, visit www.dfw.state.or.us/fish/SeaLion/index.asp