Kill Sea lions who eat salmon

“If you’re a seal, the Ballard Locks are a great place to find a snack. Seals eat a lot of salmon as they migrate through the Locks’ fish ladder to try to reach spawning grounds on the other side. Some of those salmon are Chinook, the only food of the starving Southern Resident orcas.” -- Elis O’Neil, KUOW.org, September 23, 2020.

What I think

If you’ve visited the Ballard Locks in Seattle or Willamette Falls near Portland, you might have witnessed sea lions or seals, known as pinnipeds, feasting on salmon in a natural buffet line. These man-made choke points—perfect for a patient, opportunistic pinniped—exacerbate the struggle to protect salmon runs while managing a booming population of protected marine mammals.

Despite costly attempts to scare pinnipeds off with rubber bullets or loud deterrents, they continue to make their way back to these salmon-rich bottlenecks. Stories like that of Herschel, a notorious sea lion relocated hundreds of miles down the California coast at a significant taxpayer expense, highlight the challenge. In Herschel’s case, as in many others, the sea lions promptly returned to these lucrative hunting grounds.

Before we dramatically altered the physical landscape, salmon and pinnipeds coexisted naturally. But as we built waterways and infrastructure—like locks and fish ladders designed to help salmon return to spawning grounds—we also created choke points. These areas have since become hotspots where hungry pinnipeds converge on delicious salmon.

Meanwhile, on land, we’ve systematically destroyed salmon habitat through development, prompting us to pass protective measures like the Endangered Species Act in 1973, listing several salmon populations as endangered. Ironically, the year before this Act, we began protecting marine mammals, whose populations have since rebounded, filling marinas and docks along the West Coast with 700-pound sea lions that are as noisy as they are numerous.

Today, as infrastructure needs explode and environmental policy becomes more complex, so does the difficulty of managing these two protected species. However, an often-overlooked part of this story is that Congress actually allows limited lethal removal of pinnipeds at locations like the Columbia River, Ballard Locks, and Willamette Falls. Under the Marine Mammal Protection Act, state agencies (with federal authorization) have occasionally exercised this authority. Still, don’t expect to witness any dramatic shootings in public —lethal removal requires capturing the animals and taking them away for euthanasia.

This challenging balance between conserving salmon and managing pinniped populations shows how complicated wildlife policy becomes. There is no easy solution.

Why should you care

 Next time you visit Ballard Locks, Willamette Falls, or another salmon bottleneck and spot pinnipeds enjoying their feast, take a moment to dig into the full story behind what you’re seeing. Tour guides and other visitors might focus on the resilience of salmon or the nuisance of the sea lions, but there’s more to it. Legal lethal control is often left out of public discussions, possibly to avoid a public relations mess.

Recognizing these conflicting policies can give you a new perspective. Congress often crafts legislation that, paradoxically, contains provisions that work against its own stated goals. The Marine Mammal Protection Act is a classic example: while designed to protect pinnipeds, it also allows for their removal when they threaten endangered salmon runs. These contradictory solutions reflect the tangled realities of wildlife policy.

But most of all, think of the adult salmon who only wants to get home. After years in the ocean, dodging predators, navigating deteriorating habitats, and battling poor water quality, each one makes a grueling journey back to its birthplace to spawn. They don’t have Google or Apple Maps; they’re guided by instinct alone. Yet at the very last stretch, after an incredible journey, they could lose to a waiting sea lion.

Disclaimer: I worked on a 2018 environmental review for the lethal take of sea lions at Willamette Falls, when I was a contractor for NOAA Fisheries. The review can be found at https://www.fisheries.noaa.gov/west-coast/laws-policies/marine-mammals-nepa-documents 

For more information:

https://amp.theguardian.com/us-news/2020/aug/15/us-sea-lions-columbia-river-salmon-steelhead-trout

https://www.kuow.org/stories/seals-keep-snacking-on-salmon-at-the-ballard-locks-researchers-are-trying-a-new-way-to-stop-them

https://hakaimagazine.com/features/herschel-the-very-hungry-sea-lion/ 

https://www.fisheries.noaa.gov/feature-story/california-sea-lion-population-rebounded-new-highs

https://www.govlink.org/watersheds/8/pdf/Pinniped_Mgmt_Recs_Ballard_Locks_final_Jan2024.pdf

https://www.opb.org/news/article/kill-sea-lions-oregon-willamette-falls/