Monday August 29, 2022

Hakai Magazine

Each summer at the Ballard Locks near Seattle, Washington, thousands of tourists gather to watch steelhead trout and coho, sockeye, and chinook salmon valiantly leap up the fish ladder as they head from Puget Sound to Lake Washington and the spawning grounds beyond. So, too, do a handful of hungry seals and sea lions.

“Pinnipeds—seals and sea lions—are way smarter than I think we give them credit for,” says Laura Bogaard, an ecologist with Oceans Initiative, a Seattle-based nonprofit research organization. “They figured out it’s an all-you-can-eat buffet.”

For decades, pinnipeds have been congregating at the Ballard Locks to gorge themselves on fish populations already stressed by pollution, habitat loss, and overfishing. To protect the fish, conservation managers have been trying a variety of methods to shoo them away. They installed a fiberglass killer whale that bellows predatory calls and used a device known as a pinger to try to scare the pinnipeds away. (The pinger, it turned out, had more of a dinner-bell effect.) They have even fed the pinnipeds fish laced with lithium chloride, a noxious but not deadly chemical, and continue to use firecracker-like seal bombs.

Nothing they’ve tried seems to work. The issue has been so longstanding that some conservation managers argue for measures as extreme as culling problematic pinnipeds.

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