PORTLAND, Ore. - Wildlife officials have tried everything to keep sea lions from eating endangered salmon, dropping bombs that explode underwater and firing rubber bullets and bean bags from shotguns and boats. Now they are resorting to issuing death sentences to the most chronic offenders.
A California sea lion last week became the first salmon predator to be euthanized this year under a program that is administered by wildlife officials in Oregon and Washington and the National Oceanic and Atmospheric Administration.
Last year, 11 sea lions were euthanized. Four were transferred to zoos or aquariums.
The sea lions represent a massive headache each year as chinook salmon begin arriving at the Bonneville Dam east of Portland, congregating in large numbers as they return from the ocean. Sea lions have become keenly aware that the dam is a great spot to feast on salmon, easy pickings as they wait to go up the dam's fish ladders.
"They learn. They come up here and know it's a good place to eat, and sooner or later the salmon are going to arrive," said Robert Stansell, a fisheries biologist with the U.S. Army Corps of Engineers.
Sea lions have gobbled salmon forever. But their numbers have soared in recent years, as has the number of those cruising upriver to dine on salmon at Bonneville Dam.
At least three of the upper Columbia River spring salmon runs that pass through the dam are listed as threatened under the Endangered Species Act, most significantly the spring chinook salmon run.
The sea lions' growing numbers forced state, federal and tribal agencies to intensify efforts to protect the region's multibillion-dollar salmon recovery program. Last year sea lions ate 4,489 salmon.