The Oregon Department of Fish and Wildlife has started killing sea lions below Willamette Falls to protect a fragile run of winter steelhead.
The state got a federal permit in November to kill up to 93 California sea lions per year below the falls. So far, officials have killed three sea lions using the same traps they used last year to relocate the animals to the coast.
A recent study found sea lions were eating so many threatened winter steelhead at Willamette Falls that certain runs were at a high risk of going extinct. One year, they ate about a quarter of a run that was already down to about 500 fish.
Bryan Wright, program manager for ODFW, said half a dozen sea lions are eating steelhead below the falls right now.
“The only fish in the river right now are the winter steelhead," he said. "If we can remove all these sea lions right now that will be a huge benefit to them.”
Wright said the state plans to kill about 40 of the sea lions that frequent the falls by May. Then, he said, the number of sea lions returning in future years should drop to single digits.
Before the state got permission to kill sea lions at the falls, ODFW tried relocating about a dozen sea lions to the coast in pickup trucks. But all the sea lions they drove to Newport wound up swimming back to Willamette Falls. While the effort may have saved some fish from getting eaten, officials concluded it wasn't a long-term solution.
"Unfortunately, that didn’t work," Wright said. "But one benefit of that work was that we figured out how to safely capture them, move them, transfer them and figure out all the logistics. Because of that effort we were able to quickly pick up where we left off and start the lethal removal program using the same techniques."
Oregon and Washington have already killed more than 150 sea lions below Bonneville Dam to protect threatened and endangered salmon on the Columbia River. The animals are trapped in cages and chemically euthanized under supervision of a veterinarian.
Congress passed a bill last month that will make it easier for states and tribes to kill sea lions, but that bill hasn’t taken effect yet.