<img height="1" width="1" style="display:none" src="https://www.facebook.com/tr?id=192888919167017&amp;ev=PageView&amp;noscript=1">
Thursday, September 28, 2023
Sept. 28, 2023

Linkedin Pinterest

Sea lions, seals might be hampering Washington salmon recovery. What can be done?


SAN JUAN CHANNEL — The earthy, fishy smell wafted aboard Joseph Gaydos’ research vessel first. Then came the guttural growls.

Dozens of massive tan Steller’s sea lions were resting on the rocky islet.

Gaydos, science director at SeaDoc Society, estimated 100 sea lions were hanging out. Sites like this one, at Whale Rocks off Lopez and San Juan islands, are now havens for more of the charismatic sea lions and seals than ever.

And they’re hungry for the Pacific Northwest’s endangered salmon.

While seal and sea lion populations are at the highest since counts began, salmon populations that help feed the mammals are down to 6 to 7% of their historical abundance, Gaydos said.

State officials are now exploring whether to kill sea lions and seals in the Salish Sea and outer coast in a desperate effort to save salmon species from extinction. A new report commissioned by the state Legislature and completed by the Washington Academy of the Sciences says seals and sea lions are likely impeding salmon recovery, and the full impacts of predation on salmon may not be fully understood without lethal intervention.

The report and new recommendations from a committee of scientists are ramping up the decades-old conversation about seals and sea lions eating too many salmon and how humans should or shouldn’t intervene. The pinnipeds, as they’re formally known, were documented taking advantage of human-made barriers like dams, locks and floating bridges to corral fish for a feeding frenzy. Washington state was authorized by Congress to expand a program to capture and euthanize sea lions in the Columbia River Basin in 2018.

Now similar actions are being considered in the Salish Sea, from Hood Canal to the San Juans, and even to the Washington coast.

It’s a brutal and controversial option that some researchers say has the potential to save culturally, economically and ecologically important fish on the brink.

While serving on Gov. Jay Inslee’s Southern Resident Orca Taskforce, Gaydos heard the impassioned opinions on whether or not pinnipeds are the problem. Southern resident orcas’ primary food source is Chinook salmon, and helping Chinook would ultimately help starving orcas.

About four years ago, Gaydos suggested pulling together the latest research and taking another look at whether an informed decision can be made. Under the taskforce’s recommendation, the Legislature allocated $140,000 in funding for the project.

“This is something we all need,” Gaydos said. “We need to find a common ground of what our level of understanding is about the science.”

The state Department of Fish and Wildlife sent the report to the natural resource and appropriations committees in the Legislature in November. The governor’s budget proposal includes the request for the ongoing pinniped work to continue.

Fish and wildlife officials in the meantime will continue building on pinniped population surveys and diet studies. According to officials, the agency will need funding to study the management options and determine what’s next.

Unintended consequences

Midden sites — archaeological sites including domestic waste — along Washington’s north coast have revealed the northern fur seal had long been one of the top food sources for the ancestors of the Makah Tribe and other coastal tribes, said Jon Scordino, Makah marine mammal biologist and a member of the committee that led the new report. And there’s evidence that some Indigenous people up and down the West Coast — from California to Alaska — hunted seals and sea lions for thousands of years.

Colonizers nearly hunted the creatures to extinction for the fur trade, at the same time severing some Indigenous peoples’ access to subsistence culture. Congress in 1972 passed the Marine Mammal Protection Act to help seals, sea lions and other animals rebound without the threat of human intervention.

The law was a success, re-wilding the Salish Sea and coast of Washington with more whales, sea lions, harbor porpoises and seals than had been seen in a generation (with the exception of imperiled southern resident orcas that frequent Puget Sound and feed on endangered Chinook).

Three mammals specifically have skyrocketed. From 1975 to 2015, the harbor seal population in the Salish Sea exploded from about 6,000 to around 50,000. And California sea lions rose from 50,000 to somewhere around 300,000 on the West Coast of the U.S., according to the Northwest Indian Fisheries Commission. Populations of Steller’s sea lions living around Washington, Oregon and California steadily rose from an estimated 15,000 in 1982 to .

The animals have been granted more protections than many other marine species.

Because of that, Scordino said, the ecosystem is now out of balance.

“When we remove humans as predators it causes an abundance of pinnipeds,” he said. “In some ways, that’s great. But it does have an impact on the other components of the ecosystem: salmon and forage fish like herring and other things.”

Longtime Washingtonians may remember Herschel and his posse of sea lions who made the news in the 1980s for slurping up steelhead in the Ballard Locks before the fish could make it to their spawning grounds.

Fisheries managers tried almost everything to stop the pinnipeds from decimating fish populations in the locks and elsewhere. A fiberglass orca decoy named “Fake Willy” and chemical-stuffed fish couldn’t stop Herschel. And efforts to haze sea lions in the Columbia River with firecrackers, seal bombs and recordings of orca calls failed. Fisheries managers even tried driving the creatures hundreds of miles away.

But they always came back, Gaydos said.

They’re smart animals, no different than your pet dog, he said. And they’re just doing what they know best, hunting tasty salmon, often while using human-made barriers to their advantage.

Emerging research

While more research is needed to better understand the relationship between pinniped predation and salmon abundance, the report found seals and sea lions are, at the very least, a factor affecting salmon recovery.

Many of Washington’s salmon runs are on life support: Some of the fish are raised from eggs in hatcheries and slowly released to the hostile waters, while others need to be trucked around human-made barriers to their habitat. These efforts are seeking to prevent losing species to extinction while tribes, nonprofits and other local governments work to recover the Salish Sea from habitat destruction, pollution and climate change.

“We’re doing a lot of work to restore habitat, to rebuild populations in the river and to get better ocean survival,” said Jason Gobin, Tulalip fish and wildlife director. “But we’re losing half of those fish we’ve put forward to the seals and sea lions.”

Seals and sea lions were first documented meddling with net-caught fish in Tulalip Bay, near Marysville, in the 1980s.

On a subfreezing December day last year, about a dozen silvery speckled harbor seals opened their eyes and shimmied their bodies along the edge of a log boom, awakened by sputtering fishing boats coasting into the Tulalip marina. In the late fall, a few dozen of the seals often hunt spawning chum salmon in Tulalip Bay as the fish make their way back to Battle Creek, Gobin said. The seals usually retire to the log boom for an afternoon nap.

It was only recently understood that pinnipeds eat juvenile salmon too, said Megan Moore, a National Oceanic and Atmospheric Administration research fisheries biologist who served on the committee leading the report.

Her research on steelhead survival rates at the Hood Canal Bridge was really telling, she said.

Steelhead are slowing down at the bridge — the concrete pontoons supporting the floating bridge deck extend about 15 feet under the surface of the water, creating a barrier for animals migrating at or near the surface. When they encounter the bridge they basically hit a concrete wall. That backup creates a drive-thru buffet for pinnipeds, leading to a fish survival rate of about 50%.

“And it doesn’t seem to be improving,” Moore said. “It seems to have gotten worse in the last few years.”

A 2016 sampling of harbor seal poop around Puget Sound revealed the seals rely on Chinook salmon for about 1 or 2% of their diet. That small percentage equaled an estimated 1.4 million juvenile Chinook a month.

Even in places with fewer barriers to fish passage, like the Nisqually estuary that has been restored mostly back to its natural state, pinniped predation rates are high, Moore said.

About 20% of the baby steelhead migrating through the Nisqually estuary die. And, according to a 2022 study, about 90% of those deaths are from harbor seals.

Pinnipeds have reaped the benefits of sweeping federal protections. But salmon and steelhead, most classified under the Endangered Species Act as threatened or endangered, have foundered. Unlike seals and sea lions, salmon and steelhead can be harvested. And much of their freshwater habitat includes physical and climate-driven barriers like low water levels and rising temperatures.

Each year salmonid species hatch in the cool freshwater tributaries of the Salish Sea. Some of them rely on estuaries to gear up for survival. Here, fish go through a process where their scales harden and change. They prepare to head into a different ecosystem — the ocean — and the most dangerous time of their life thus far.

About 5 million wild and roughly 25 million hatchery Chinook make the journey from the Salish Sea to the Pacific Ocean each year. A “non-trivial” amount stay within Puget Sound.

Wild populations of all salmon and steelhead have decreased since the 1970s, while hatchery production of Chinook, chum and pink salmon has increased.

In the late 1970s, salmon had a better shot at surviving in the saltwater than today, according to a 2021 study cited in the report. While there are many possible causes of that mortality, “pinniped predation is considered a primary driver of increasing mortality rates.”

The new report commissioned by the Legislature suggests the problem is nuanced.

Some estuaries may see much higher levels of predation by seals and sea lions, and in others, other players like birds and other animals may be affecting salmon, said Casey Clark, the lead marine mammal researcher for the state Department of Fish and Wildlife.

The agency has started to study specific sites where seal and sea lion predation has been reported. Preliminary data from a pilot project on the Stillaguamish River shows that seal predation may not be the biggest limiting factor for two populations of threatened Chinook — other predators and factors are at play.

“When we are thinking about predation management, there’s a lot of uncertainties that are raised,” said Nate Pamplin, director of external affairs for the Department of Fish and Wildlife.

“Oftentimes those uncertainties kind of implied like the conversation should end,” he said. “And here, the Academy of Sciences have pulled in all that uncertainty and said even with that uncertainty, they still felt that there was a preponderance of evidence that pinniped predation may be impeding salmon recovery and thus, managers, you should probably consider pursuing the next step.”

Delicate next steps

So what would “lethal intervention” look like?

In 2018, Congress approved a change in the Marine Mammal Protection Act to allow for more sea lions to be killed in a portion of the Columbia River to reduce predation on salmon and steelhead. And in 2020, Congress approved an amendment to up the ante.

In the highly altered Columbia River basin, managers including tribes and Washington and Oregon state fish and wildlife officials have permanently removed 380 California and Steller’s sea lions. Some sea lions were trapped and placed in captivity, and others were euthanized.

Use of firearms is prohibited. Instead, a combination of trapping and darting can be used, with the kill administered by a lethal injection of tranquilizing drugs.

It took about a decade to amend the federal legislation to expand lethal management on the Columbia.

The proposal received 22,000 comments during public review. Fewer than 200 of those comments were in support.

Sea lions are not the sole offender in blocking salmon recovery; it’s also habitat degradation, harvest and hydro systems blocking the passage, Sharon Young, former marine mammal field director for the Humane Society, said in a 2020 interview. And, she said, predator management hasn’t worked as expected in the past.

But lethal intervention on the Columbia moved forward thanks to the political will and research behind it, said Scordino, the Makah biologist.

“So now, whether or not we can have something outside of a system like the Columbia — which is well outside of the normal range of where the pinnipeds are — it’s a little bit different,” he said.

It’s unknown how removing pinnipeds would affect the greater Salish Sea ecosystem.

For example, wolves kill elk and deer, said Gaydos, the SeaDoc science director. But biologists know that wolves benefit the population and the ecosystem by being around.

“That’s something we don’t really understand with pinnipeds right now,” he said. “If we were to remove pinnipeds, what would the impact be on other predators of salmon? How would that affect hake? How would that affect dog fish populations?”

Selectively euthanizing seals and sea lions would likely pose little risk to their populations, the new report suggests. But, unlike the salmon-eating southern resident orcas, Bigg’s orcas prey on pinnipeds. Messing with the food web could have broader implications.

And it’s unclear if other predators would eat those salmon even if pinnipeds were removed.

There’s a lot of research to be done and approvals to be received before lethal intervention is on the table, said Pamplin, the state fish and wildlife external affairs director.

Storytellers, policymakers and advocates have long sought to point fingers at a couple of things affecting salmon recovery, said Jay Julius, founder of Se’Si’Le, an Indigenous-led environmental nonprofit. It’s much bigger than the sea lions, he said. It’s humans acting as superior beings and extracting from the natural world.

“I think that’s the pattern that’s led us to where we are. Salmon are being managed by the state and feds to extinction, and therefore, my people, myself are being managed to extinction whether we like it or not,” he said. “We need a different outlook.”