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Sea Lions Gobble Up Salmon in NW

A new bill would allow the killing of some sea lions to stop the scourge of salmon predation in the Columbia River.
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Each year in the early spring, California sea lions leave the Pacific Ocean for the Columbia River for a fish feast, swimming 145 miles upriver to the Bonneville Dam to gorge on spring Chinook salmon, steelhead, and other fish, many from runs protected under the federal Endangered Species Act.

Tribal fishers first noticed the sea lions 20 years ago. Oregon, Washington and Idaho began monitoring in 2002, and since, sea lions have eaten tens of thousands of migrating fish in the Columbia River. They consume 20 to 45 percent of the spring Chinook salmon—especially revered by the Warm Springs, Umatilla, Yakama and Nez Perce treaty tribes—for their importance to tribal ceremonial life.

The sea lions’ exponentially increasing population has frustrated efforts to recover the river’s endangered fish populations, say U.S. Representatives Jaime Herrera Beutler (R-Washington) and Kurt Schrader (D-Oregon). The lawmakers introduced a bipartisan bill, the Endangered Salmon and Fisheries Predation Prevention Act, that builds on previous versions of legislation to remove permanently a limited number of predatory California sea lions that cause the most harm.


“BPA ratepayers and my constituents pay hundreds of millions of dollars annually as part of the largest mitigation program in the country for threatened and endangered species,” Rep. Kurt Schrader said in a statement, referring to the Bonneville Power Administration. “Even the National Marine Fisheries Service called the mortality of salmon returning to the Columbia River Basin that’s attributable to sea lions alarming. This legislation will provide the states and tribal managers the authority they need to eliminate this threat once and for all.”

A key provision in the bill would provide tribes with the same authority currently allowed the states. As it stands, the Columbia River Inter-Tribal Fish Commission (CRITFC), which provides fisheries management, biological and environmental research to the tribes, is limited to hazing the animals. But non-lethal measures alone are not and will not be sufficient to ensure survival of endangered salmon, said Charles Hudson, Intergovernmental Affairs Director at CRITFC.

“The experience at Ballard Locks proves this,” Hudson said. “Same story on the Columbia. The river is too big, the sea lion population too large, for hazing alone to halt the problem.”

California sea lions first appeared at Seattle’s Ballard Locks in the 1970s, feasting on winter steelhead clustered at the fish ladders. Other sea lions joined them. Biologists shot at them with rubber bullets. They used underwater firecrackers, acoustic harassment, and fed them fish poisoned to make them sick to their stomachs. The sea lions learned how to avoid the biologists.

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Removing the sea lions from the Locks didn’t work, either.

Wildlife managers trucked 39 Californias to the outer Washington coast in the late 1980s. Of those, 29 came back. Then they trucked them to California. It only slowed them down. That was before options for lethal removal, and by 2008 the Ballard Locks steelhead run was extinct.

Although conditions differ on the Columbia River, a task force agreed that sea lions were taking such a toll on threatened and endangered fish at the Bonneville Dam that it warranted permanent removal of documented problematic animals. Animal rights advocates, including the U.S. Humane Society, have intervened in the past to stop the lethal removal of sea lions.

The Bonneville Dam on the Columbia River, where sea lions feast on endangered salmon.

The Bonneville Dam on the Columbia River, where sea lions feast on endangered salmon.

State wildlife managers have removed 161 sea lions since 2012, and this year NOAA Marine Fisheries reauthorized the five-year decision through 2021. But last year alone around 190 sea lions killed more than 9,500 adult spring Chinook within sight of the dam.

A review this year by the National Marine Fisheries Service of the removal plan concluded that predation has continued to increase at an unprecedented rate, and management efforts are insufficient to reduce the severity of the threat, especially in the Columbia River and at Willamette Falls (in Oregon).

Yakama Nation Tribal Councilman Gerry Lewis said all parties involved in Columbia Basin fish issues have compromised so that endangered species can survive. The treaty tribes, who ceded millions of acres and reserved their rights to fish, have greatly reduced their fisheries, he said. So have commercial and sports fishers. Hydro dams have given up power production to spill water at a cost to taxpayers, while agricultural operations in some of the country’s most fertile land have had to curtail irrigation.

Sea lions, like the tribes who fish the Columbia, have been here for millennia. Only 10,000 California sea lions were left when Congress passed the Marine Mammal Protection Act in 1972. It’s a great success story. Their numbers exploded to 300,000 today. The Act now recognizes, though, that their growing population of predators is jeopardizing salmon and steelhead stocks in the Columbia River and putting them at risk of extinction.

“Our tribes are working hard to restore ecological balance to a highly altered and degraded river system,” explained CRITFC Chairman Leland Bill. “The Marine Mammal Protection Act and the Endangered Species Act are thoughtful laws. However, they need to be reconciled with one another.”