January 31, 2019 โ The following is excerpted from a story published today by The Atlantic:
Let us first establish that sea lions are supposed to live in the sea.
Since the 1990s, however, male sea lionsโa handful at first, now dozensโhave been captivated by the attractions of the Willamette River. They travel all the way from Southern California to Oregon and then swim up 100 miles of river to arrive at an expansive waterfall, the largest in the region. Here, salmon returning to spawn have to make an exhausting journey up the fish ladders of the Willamette Falls. And here, the sea lions have found a veritable feast.
โ[Theyโre kind of sitting ducks,โ the wildlife biologist Sheanna Steingass told me, describing the salmon. She paused to consider the metaphor. โOr sitting fish.โ Every sea lion eats three to five fish a day.
In another world, this could just be a story about the intelligence of sea lions and their adaptability to river life. But in this worldโwhere salmon populations throughout North America have plummeted, and where the winter steelhead run at Willamette Falls has fallen from 25,000 fish in the 1970s to just hundreds in 2018โitโs a dire story for the fish. After spending years trying and failing to deter the sea lions by nonlethal means, the Oregon Department of Fish and Wildlife, where Steingass leads the marine-mammal program, started โlethal removalโ of sea lions in December. As of mid-January, they have trapped and euthanized five sea lions at Willamette Falls.
Killing animals to save other animals is always controversial. Animal-rights groups like the Humane Society of the United States denounced the sea-lion killings, calling them a distraction from the salmonโs real problems. And itโs true that a long chain of human actionsโoverfishing, destruction of salmon habitats, dams blocking their migration, hatchery mistakesโhave led to what everyone can admit is this nonoptimal situation.
โIn a perfect world, in an unaltered world, this wasnโt a problem, because historically there were 16 million salmon in the Columbia River,โ says Doug Hatch, a senior fisheries scientist at the Columbia River Inter-Tribal Fish Commission. The sea lionโs appetites would have barely made a dent. Itโs only because humans have so unbalanced the natural world that as drastic an action as culling sea lions could appear to be the fix.
Read the full story at The Atlantic