To some people, sea lions are smart, lovable creatures that shouldn’t be harmed in any way. To others they’re loud, destructive pests that need to be controlled.
As sea lion populations grow, both sides have gripes about how these hulking pinnipeds are being managed on the Columbia River.
Some want to see wildlife managers kill more sea lions to protect fragile runs of salmon and steelhead – especially as new research suggests sea lions may be eating a lot more fish than previously thought. Others say killing sea lions is scapegoating, and it won’t solve the bigger environmental problems that put the fish at risk in the first place.
This spring, around 2,400 barking sea lions piled into Astoria’s East Mooring Basin – astonishing biologists who have been monitoring them here for years. The sea lion numbers shattered last year’s record of 1,400 of these marine mammals in the marina.
A lack of food in the ocean and a big smelt run drew them in and soon California sea lions, which can weigh 700 pounds or more apiece, had taken over the Astoria docks that should be harboring boats. That alone is problem for Bill Hunsinger, who oversees those docks as a commissioner with the Port of Astoria.
“They’ve absolutely destroyed them,” he said. “You can’t bring people down to these docks when you have this type of situation.”
But the port’s damaged, unusable docks are only the beginning of Hunsinger’s problems with sea lions that he have been sinking boats, disturbing nearby hotel guests and even biting people and their dogs, he said.
And that’s on top of all the prized spring salmon they’re eating – at times plucking them right off the lines of recreational anglers.
“The fisheries are going to be lost,” he said. “I talked to three guys who went fishing two weekends ago. They had nine fish on and never got one to the boat. Lost ’em all to sea lions.”
Experts say the overall California sea lion population is as big as it’s ever been, thanks in part to the 1972 Marine Mammal Protection Act’s restrictions on hunting or harming them. Fish and wildlife managers with Oregon and Washington have killed about 70 sea lions on the Columbia to protect threatened and endangered salmon and steelhead. But Hunsinger and others say they should be killing more.
To protect fish runs from sea lion predation, Columbia River tribes are hoping to get authorization from Congress to kill more sea lions – beyond what the states of Oregon and Washington are authorized to kill.
Right now, Columbia River Indian tribes’ fish commission is using non-lethal hazing to try to deter sea lions from eating salmon at Bonneville Dam – the first bottleneck for fish on the river. As thousands of returning adult salmon and steelhead swim to their spawning grounds to reproduce, the dam slows them down and makes them easy pickings for sea lions.
Below the dam, tribal members chase down sea lions and shoot firecrackers at them to push the animals farther downriver and away from the bottleneck.
But with dozens of sea lions feeding near the dam, it’s not hard to find one tearing through a fish, thrashing his head out the water to break off a bite while sea gulls swoop down for the scraps.
This is what managers call a predation event. And according to Doug Hatch, a senior fisheries biologist for the Columbia River Inter-Tribal Fish Commission, non-lethal hazing with firecrackers can only do so much to prevent it.
“For the times that we’re hazing, it’s pretty effective,” Hatch said. “But as soon as we leave the animals will come back.”
Hatch said more sea lions should be killed to protect fragile runs of salmon and steelhead – not just at Bonneville but throughout the lower river.
Looming over the debate about managing sea lions is an ominous number. Last year, a federal study that tracked returning salmon from the mouth of the Columbia to Bonneville Dam found that 45 percent of the fish went inexplicably missing somewhere along the way.
“The smoking gun is sea lions,” Hatch said. “Sea lion abundance has increased tremendously over the past several years – particularly this year it’s much higher than we’ve seen it before.”
It’s unclear exactly how many of the missing fish were eaten by sea lions, but if all of them were, that’s a huge portion of the salmon people are spending millions of dollars trying to protect and restore – much bigger than the 2-5 percent rate of sea lion predation of salmon documented the U.S. Army Corps of Engineers at Bonneville Dam.
A new experiment this year aims to fill the gaps in what we know about how many salmon sea lions are eating in the Columbia. Scientists have tagged some sea lions with accelerometers that track the distinctive head-shaking motion they make when they eat salmon. Managers are hoping that the tags will allow them to get a better count on how many fish sea lions are eating in the 146 miles of the river below Bonneville Dam.
But no matter how many salmon sea lions are eating, people who love sea lions contend that it’s wrong to kill them for doing what they naturally do.
“Sea lions are beautiful, amazing animals,” said Ninette Jones of the Sea Lion Defense Brigade. “We have just been blown away by the outpouring of support for these animals.”
Jones’ group watches over sea lions in Astoria and at Bonneville Dam. She said sea lions have a natural predator-prey relationship with salmon and it’s actually people who have put salmon at risk of extinction. Given all the other environmental problems on the Columbia River, including the dams, she said, blaming sea lions is taking the easy, cheaper way out of the complex problems people have created on the river.
“The salmon populations were going extinct when there were no sea lions in the river back in the ’80s,” she said. “So to draw the connection that the sea lions are causing the extinction of salmon it’s basically scapegoating but it’s not going to address the real cause of the extinction of salmon. Even if they killed all the sea lions it’s not going to save the salmon.”
Jones also argues having state wildlife managers killing sea lions is encouraging people to take matters into their own hands and to shoot sea lions illegally. Earlier this month, her group found sea lions bleeding on the docks in Astoria from apparent gunshot wounds.
Robin Brown, marine mammal program lead with the Oregon Department of Fish and Wildlife, defended his agency’s policy of lethally removing some sea lions. The state only kills sea lions that have been identified and observed eating salmon below Bonneville Dam, he said, and the 73 killed since 2006 represent a tiny portion of the total population.
“We try to manage for the resource that’s at the greatest risk,” Brown said. “There are over 300,000 California sea lions in the population now and that population is at no risk whatsoever. Yet a lot of these salmon and steelhead populations have been reduced, granted through the actions of people over many years, but those very small populations of salmon and steeled are at great risk of extinction.”
Back in Astoria, port commissioner Bill Hunsinger disagreed with Jones about the effect of the government’s lethal removals. He said the government needs to increase its lethal removal of sea lions to prevent more people from taking matters into their own hands and shooting them illegally. But he doesn’t disagree that sea lions are beautiful.
“Well, they are. And they’re entertaining,” he said. “But they need to go entertain somebody else in someplace else.”
Soon many of the sea lions will leave the Columbia River for their breeding grounds farther south. But there’s little doubt they’ll be back – barking and eating fish again – next spring.
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