Fury erupts as sea lions face ‘mass slaughter’ in three US states,
A debate has intensified across the Pacific Northwest as officials consider expanding the lethal removal of sea lions in an effort to protect declining salmon populations and support regional fisheries.
An estimated 4,000 to 4,500 sea lions inhabit the Columbia River basin across Washington, Oregon and Idaho, where the animals feed on migrating salmon and steelhead.
Supporters of the effort argue sea lion predation has become a growing threat to already vulnerable fish runs relied on by local communities, tribal fisheries and commercial fishermen.
The push gained momentum in April after Washington Representative Marie Gluesenkamp Perez urged the Trump administration to approve the ‘direct, lethal removal’ of sea lions to help protect threatened salmon populations.
Gluesenkamp Perez said sea lions have at times eaten four times more salmon than fishermen and Native American tribes harvest in a year.
She also noted that nearly one in four fish passing through Bonneville Dam during the 2025 spring season showed wounds linked to sea lion bites.
Critics, however, argue sea lions are being unfairly blamed for a crisis driven largely by habitat destruction, overfishing, hydroelectric dams and climate change.
One X user wrote: ‘I do not support the mass slaughter of the sea lions, which are not invasive, for preying on their natural prey.’
An estimated 4,000 to 4,500 sea lions inhabit the Columbia River basin across Washington, Oregon and Idaho, where the animals feed on migrating salmon and steelhead.
The Columbia River Basin once sustained between 10 million and 16 million salmon and steelhead, but more than one-third of those historic populations are now extinct, while many remaining runs are considered critically low.
Sea lions often congregate below Bonneville Dam, where migrating fish are forced through narrow passages that make them easy targets for predators.
Gluesenkamp Perez argued the crisis has reached a breaking point, claiming sea lions have at times eaten four times more salmon than fishermen and Native American tribes harvest in a year.
She also said nearly one in four fish passing through Bonneville Dam during the 2025 spring season showed wounds linked to sea lion bites.
‘When grocery prices are at record highs, it is insulting to my community to waste taxpayer dollars while fishermen continue to be denied their ability to put food on the table for their families,’ she said. The Daily Mail has contacted Gluesenkamp Perez for comment.
Sea lions remain protected under the Marine Mammal Protection Act of 1972, which generally prohibits harassing, capturing or killing marine mammals without federal authorization.
Congress expanded removal powers in 2018, allowing wildlife managers to remove up to 540 California sea lions and 176 Steller sea lions over five years, although officials say far fewer animals have actually been removed.
Under current rules, authorities trap sea lions near dams and fish ladders before euthanizing them under veterinary supervision. Officials also use underwater explosive deterrents known as ‘seal bombs’ to drive the animals away from salmon migration routes.
Authorities have used underwater fireworks to deter sea lions from the waters, but studies have found that the non-lethal tactic could cause severe injuries and even death. Pictured is a sea lion suspected of enduring a firework, resulting in its bulging eyes
Seal bombs detonate underwater, creating shockwaves that can damage marine mammals’ hearing or cause serious injuries. Necropsies on sea lions recovered by
The Marine Mammal Center found trauma believed to be linked to the blasts, including fractured jaws, burns and severe tissue injuries.
NOAA Fisheries has previously described sea lion predation as a significant threat to several endangered salmon runs in the Columbia Basin. Officials have also argued that non-lethal deterrence alone has not stopped sea lions from returning to key feeding areas near dams.
Critics, however, argue sea lions are only one factor contributing to the salmon crisis and say habitat destruction, overfishing, hydroelectric dams and climate change have played larger roles in the decline.
Supporters of the effort argue sea lion predation has become a growing threat to already vulnerable fish runs relied on by local communities, tribal fisheries and commercial fishermen
Hydroelectric dams have been blamed for disrupting migration routes, altering river habitats and increasing mortality rates for juvenile salmon traveling to the ocean and adult fish returning upstream to spawn.
Experts say urban development and water diversion have also reduced and warmed river habitats needed for salmon spawning, while climate change has disrupted both freshwater and ocean stages of the fish’s life cycle.
One X user wrote: ‘The dams are basically making it so that they have an all-you-can-eat salmon buffet.’
Another posted: ‘I do not support the mass slaughter of the sea lions, which are not invasive, for preying on their natural prey.’
Others, however, defended the removals, arguing sea lions have increasingly learned to gather near bottlenecks where salmon are especially vulnerable.
One local user wrote: ‘They do not naturally come as far upstream as they have been, but they’ve learned fish like to congregate near obstructions like Bonneville or Willamette Falls. They decimate native salmon and sturgeon populations.’
