Every day at 6 AM, a team of Oregon Fish and Wildlife officers check the traps. The cages encircle docks—sea lions love sunbathing—throughout the Columbia River Basin, at a strategic point just before the Willamette Falls, a natural feature in a tributary of the same name. If a trap door is closed, officers barge the sea lion out of the river and wrangle the agitated mammal into yet another trap, before driving it 230 miles to the California coast, only to have the same sea lion virtually beeline back to the same stretch of the Columbia.
At which point, the cycle begins all over again.
For a decade now, OFW has been caught in this capture-release-recapture loop of trapping sea lions. Hauling a 500-pound pinniped from its watery perch can be dangerous, though it’s one of the only intervention strategies the wildlife team has had since the sea lions first moved into the Columbia River to pursue steelhead trout and Chinook salmon. The mammals are considered endangered and have extremely strict kill regulations, but those two fish types they’re eating through, the trout and salmon, are likewise both threatened and endangered species. If the trap-release-retrap circle continues, OFW thinks there’s a high likelihood one of those fish populations will go extinct.
It’s a case study in the unforeseen consequences of well-meaning attempts at wildlife conservation, so protective as to be counterproductive. As more and different kinds of nonnative sea lions have arrived in the Columbia River Basin over the years, state, federal, tribal, and animal rights organizations remain locked in negotiations over legal precedents and predicted ramifications. Things came to a head at the end of January when the governors of Idaho, Washington, and Oregon asked Congress to lift some restrictions on the lethal removal of the endangered sea lions.
Oregon officers are permitted to kill 92 sea lions each year, but Shawn Clements, a senior policy advisor with OFW, calculates a 90 percent chance of at least one Oregon fish run being wiped out in the coming years if state management groups aren’t granted more, and easier, kills.
“We are essentially sitting by and watching fish stocks get to the point they are,” Clements told me. The question is, will more lethal removal actually bring the fish stocks back to healthy levels?
This problem of pinnipeds in the river began when another issue with the species was solved: The sea lion population sat at 90,000 individuals just before the Marine Mammal Protection Act passed in 1972; by 2012, that number had rocketed past 300,000.
As the population grew, a couple thousand sea lions nosed their way into the Columbia River Basin. Though there’s no historical documentation of sea lions in this region, a small percentage learned where to go, specifically the dams and waterfalls where Chinook salmon and steelhead trout, which race the same rivers to reach their breeding grounds, collect. The fish slow down at barriers like Willamette Falls and Bonneville Dam, a power generator in the Columbia and a popular tourist spot, piling up while waiting their turn to jump the impasse, often right into striking range of expectant, hungry sea lions.
This scenario cements the pinnipeds as drivers of the sinking fish numbers, says Brandon Chasco, a recent doctoral recipient who studied how western sea lions and killer whales were impacting salmon populations. “What we found was that sea lions just don’t aim to eat that much salmon except in specific locations—and one is the Columbia River,” Chasco told me. “There’s no doubt that if you took them out, you’d have more fish.”
OFW estimates the 60 to 100 sea lions cycling through Willamette Falls each year eat six to nine percent of spring salmon and 11 to 25 percent of winter trout. The trout are hit harder because their upstream return overlaps with the pre-mating, bulk-up season for male sea lions. Migrating to reproduce, the fish are snapped up before they have the chance to multiply.
Chinook salmon and steelhead trout runs across the Pacific Northwest regularly rank as the most expensive members on the endangered species list. In 2016, the population branches trying to hop the Willamette Falls received a combined $29 million from state and federal protection programs. It’s these fish that Clements predicts are most most at risk of disappearing if officials aren’t allowed to lethally remove more sea lions than they’re already permitted.
Clements also anticipates this kind of loss because it’s happened before. In the 1980s, four sea lions knocked off 80 percent of another Columbia River trout run in a single season. At the time, the Marine Mammal Protection Act allowed for no lethal removal. When the National Ocean and Atmospheric Administration approved the removal of those four sea lions in 1994, only 70 steelhead had made it past the mammals that season.
To earn its current kill limit, OFW warned of an 80s-style situation. The allocations are a case-by-case basis and very strict—pinnipeds are still endangered, after all. The 92 removals OFW is currently allowed annually are exclusive to sea lions at Bonneville Dam, and the department is currently waiting on NOAA to review its application for lethal removal at Willamette. To complete a kill, OFW has to prove to NOAA that an identifiable sea lion has been hanging around for five days and documented with salmon or trout in its mouth. If NOAA approves the target list addition, OFW then must wait for the wanted sea lion to fall into one of the traps itself. It’s only after no zoos or aquariums are willing to take in the animal that it can be euthanized.
This is why the department has never hit its limit, NOAA Portland branch chief Robert Anderson tells me. “It’s a process-heavy thing, but we’re largely okay with that, given that it’s a problem that authorizes lethal removal of marine mammals,” Anderson said. “You want to get it right.”
To OFW, the approval process isn’t keeping pace with the problem. The governors of Oregon, Idaho, and Washington agree, and asked Congress to loosen the Marine Mammal Protection Act for the sake of the fish, a commodity central to all three state economies. Clements says he watches pinnipeds stay longer each season, and that members of one species to which removal permits don’t apply, Steller sea lions, recently staked out some dam and waterfall territory. Steller sea lions average a whopping 1,200 pounds, a bulk made entirely of fish.
“These are buzzy animals and no one likes to see them being killed,” said Clements. “So it’s really hard to pass any measures. We’re not asking for the world here, we’re just asking for more flexibility.”
“This is an open system, a treadmill of death.”
Sharon Young, by contrast, thinks OFW has plenty of leeway. Young, the Humane Society field director for marine wildlife, was part of two lawsuits the organization has filed over the lethal removal requests. Young was also involved in granting the first exemption in the 80s, and to her, the situations aren’t the same. Back then it was clear, Young says, that those four individual sea lions were to blame and had to go. But with the list of accused pinnipeds (200 and counting) now updated on a weekly basis, there’s no end in sight, she argues. What if a sea lion isn’t a problem returning every season, but rather a one-time visitor?
“This is an open system, a treadmill of death,” Young says.
Besides, there are other ways to boost threatened fish populations, according to Young. Hatchery salmon often compete with wild fish for resources, a problem USFW has acknowledged, so maybe releases could be retimed, Young says, so the bred fish pose less of a threat to wild-born, endangered fish. Or, let fishers catch all the bass. Introduced decades ago, the popular sport fish thrives in this nonnative habitat—by eating salmon. Even reducing the limit on how many salmon can be caught, Young adds, would help. The maximum catch fishers can take each year goes up to 17 percent, depending on the success of the run.
State and federal fish and wildlife agencies need to better address the other salmon threats, Young says.
“You may feel better ‘cause you got the one [sea lion] that had a fish in its mouth,” she said, “but we continue to maintain what their own facts show: what they’re doing is ineffective.”
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To the Columbia River Inter-Tribal Fish Commission, the sea lions are the last threat left to be dealt with. The organization has acted on behalf of the Yakama, Umatilla, Warm Springs, and Nez Perce tribes—the people with the most to lose when it comes to Pacific Northwest fish—on various revival strategies since 1977.
“We feel like the underrepresented action has been predation by sea lions,” Doug Hatch, a senior research scientist with the inter-tribal commission, told me. Federal laws prevent the commission from helping euthanize the animals, so the commission photographs activities and use noise-makers to temporarily scare sea lions out of harm’s way. Hatch’s division is working on tracking sea lions with motion sensors, part of a catch method known as “shake and break,” a bite-and-whip motion that registers a unique mark on the devices. Ideally, the data would help pinpoint troublesome pinnipeds sooner.
“It’s not something we want to do, lethally-removing sea lions,” said Hatch. “Protecting salmon is what we want to do.”
“It’s an emerging issue, so it’s been a scramble,” he added. “Well, maybe you can’t call 10 years a scramble.”
Meanwhile, in the first two weeks of March alone, the OFW sea lion trap team completed 11 releases. After each, the officers turned to satellite images to see how quickly the sea lions, backs branded, reappeared at the waterfall. The slowest took a week to swim back to the Columbia River Basin. The fastest made the return trip in 72 hours.
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