The Battle for the Columbia: Balancing Predators and Prey
The ecological balance of the Columbia River is reaching a tipping point. For years, a silent war has been waged between the region’s iconic salmon and steelhead and the ravenous sea lions that have claimed the river as their hunting ground.
Steller and California sea lions have migrated up the Columbia and its tributaries, discovering a convenient food source: endangered fish gathering at dams and falls. These “pinch points” make the fish easy prey, turning the river’s infrastructure into a buffet for pinnipeds.
The impact is staggering. According to data cited by Representative Marie Gluesenkamp Perez, sea lions have consumed four times as many salmon in a single year as local fishermen and Tribes have harvested. The physical evidence is undeniable; during the 2025 spring season, nearly one-fourth of the fish at Bonneville Dam showed wounds from sea lion bites.
Moving the Line: The Push for Expanded Removal Zones
One of the most significant trends in river management is the push to expand where sea lion removals can legally occur. Currently, Notice established boundaries for these actions, but advocates are arguing these limits are outdated.
Representative Gluesenkamp Perez is currently urging the Trump administration to extend the allowable removal area downriver. The goal is to move the boundary from River Mile 112, east of Camas, further down to River Mile 66 near Longview.
The reasoning is biological: by River Mile 66, near the Cowlitz River and the Lewis and Clark Bridge, the water is no longer salty enough to be a natural sea lion habitat. By expanding the zone to this point, authorities could potentially intercept predators before they move further inland to devastate local fish populations.
Rethinking the Method: From Euthanasia to Direct Action
For decades, the process of removing sea lions has been governed by strict, often cumbersome protocols. Under current guidelines, wildlife managers must often capture the animals in traps, remove them from the river, and utilize a licensed veterinarian to chemically euthanize them with darts.
Following this, carcasses must be transported to a tertiary location for disposal and autopsy. Critics argue these requirements are too “onerous and costly” to be effective against a growing predator population.
We are likely to notice a shift toward more “direct, lethal removal.” This potential change in strategy was highlighted in the 2026 Commerce, Science and Justice spending bill, which directs the National Oceanic and Atmospheric Administration (NOAA) to study which removal strategies yield the best results.
A Legal Tug-of-War: Protected Species vs. Protected Species
The conflict in the Columbia River is a classic regulatory paradox. On one side is the Marine Mammal Protection Act, which makes it illegal to harass, hunt, or kill marine mammals. On the other is the Endangered Species Act, which protects 13 threatened and endangered salmon runs.
As sea lions compete directly with anglers and Tribes, the pressure on federal agencies like NOAA to grant more exceptions to the Marine Mammal Protection Act is increasing. The future of the river’s biodiversity may depend on how the government balances the survival of a protected predator against the survival of an endangered prey.
Frequently Asked Questions
Why are sea lions a problem for the Columbia River?
They prey on endangered salmon and steelhead, often gathering at dams and falls where the fish are trapped, significantly reducing the population available for nature and local fisheries.
Is it legal to kill sea lions?
Generally, no, as they are protected under the Marine Mammal Protection Act. However, there are specific exceptions that allow state and Tribal authorities to perform removals, sometimes lethally.
What is the proposed change to removal zones?
There is a push to extend the removal area from River Mile 112 to River Mile 66 (near Longview), where the water is fresh enough that sea lions are no longer in their natural habitat.
Join the Conversation
Do you believe lethal removal is the only way to save the Columbia’s salmon, or should we seek non-lethal alternatives? Let us know your thoughts in the comments below or subscribe to our newsletter for more updates on Pacific Northwest ecology.
