Killing to Conserve

Is it effective, or ethical, to cull one protected species to help another?

Halfway up the Oregon coast at a place called Sea Lion Caves, a $14 entry fee will buy you an elevator ride 208 feet down through solid rock into one of the world’s largest sea caves. Sea Lion Caves has been a coastal tourist attraction since the early 1960s, and the elevator that takes visitors down more than 20 stories in 30 seconds deposits them into an observation area overlooking the cave and the big waves that come roaring through its entrance. Last December was a good time to visit. Heavy storms had been pounding the Oregon coast with rain and rough seas for a couple of weeks, driving large numbers of Steller and California sea lions into the cave in search of refuge, creating a cacophony of bellowing animals and booming surf.

photo of a sea lion and a salmonphoto Scott Darbey, on FlickrWildlife officials have been euthanizing some California sea lions that swim up to the Bonneviile Dam on the Columbia River and prey on migrating Chinook salmon.

From a population reduced to about 10,000 in the 1950s, California sea lion numbers have grown to nearly 390,000 since they were protected under the Marine Mammal Protection Act of 1972, which made it illegal to kill, or “take,” them without a permit. While most of the animals wintering on the Oregon coast stick to offshore habitat, bays, and estuaries, since 2000 a small number of sea lions, 100 or so, have been swimming 145 miles up the Columbia River, from its mouth at Astoria to Bonneville Dam, to eat upstream migrating salmon that stack up at the base of the dam and fish ladders. Some of the fish they devour are upriver spring Chinook salmon, which are listed as endangered under the Endangered Species Act (ESA). For that crime, the Oregon and Washington fish and wildlife departments, with authorization from the federal government, have euthanized by lethal injection at least 75 California sea lions since 2008.

Manipulating wildlife populations by killing animals, often euphemistically referred to as “control” or “removal,” is hardly new. Take the state-sponsored extermination of wolves (at the behest of livestock owners) in the middle of the twentieth century that wiped out nearly all gray wolves in the lower 48 states. More recently, between 2000 and 2010, the federal agency Wildlife Services killed at least two million native wild mammals, mostly to protect farmers’ and ranchers’ interests. Mountain lions, wolves, and coyotes are also regularly killed by state and federal wildlife agencies to increase populations of deer and elk for game hunters. Before they were federally protected, California sea lions were often shot because they competed with the commercial and sport fishing industries, and both Washington and Oregon paid a bounty on them from the 1920s into the 1960s.

But over the past couple of years, state and federal wildlife agencies have been carrying out targeted culls of certain animals and birds, and protected ones at that, for an entirely different reason: to help other more critically endangered or threatened species.

In addition to euthanizing California sea lions, wildlife officials have been shooting double-crested cormorants and barred owls, and poisoning ravens – species that have certain federal protections – all ostensibly to help struggling populations of Chinook salmon, greater sage grouse, and spotted owls – species that are either listed under the ESA or are potentially eligible for eventual listing.

This raises the question: Does killing abundant but protected wildlife to help other, more vulnerable protected wildlife represent good, scientific, and ethical wildlife management, or does it represent an attempt to avoid taking action on more important, but politically difficult, causes of a species’ decline at the expense of the targeted animals?

An investigation into the matter reveals that in many of these cases, the animals and birds the agencies chose to cull were not the root cause of the threatened species’ decline.

In Washington and Oregon, wild salmon and steelhead runs declined precipitously in the first half of the twentieth century and their populations have never fully recovered since. Currently, 13 Columbia River basin stocks of wild Pacific salmon and steelhead are listed under the ESA.

photo of a salmon, jumpingphoto by Taomeister, on FlickrUpstream migrating salmon often get stuck at the base of dams and fish ladders. The multiple impacts of dams run by the US Army Corps of Engineers on the Columbia and Snake rivers are among the key causes declining of fish populations.

The multiple impacts of hydropower dams run by the US Army Corps of Engineers on the Columbia and Snake rivers are among the key causes declining of fish populations. Dams block passage of these fish to and from their riverine spawning and rearing habitat and the Pacific Ocean. At dams where fish passage is not provided, this blockage is permanent. According to the Northwest Power and Conservation Council, more than 55 percent of the spawning and rearing habitat once available to wild salmon and steelhead in the Columbia River Basin is permanently blocked by dams. At dams like Bonneville, many ocean-bound juvenile fish – sometimes as much as 90 percent of a run – are killed by dam turbines as they swim downstream.

Sea lions weren’t the initial culprits, and even now they are hardly the only, or even the worst, offenders when it comes to salmon mortality. True, each spring, a small number of sea lions target the spring Chinook salmon spawning run. For instance, according to the Army Corps, between January 1 and May 31, 2015, California and Steller sea lions ate an estimated 8,474 Chinook salmon and steelhead at Bonneville Dam, which spans the Columbia River between Oregon and Washington State. During that time period, nearly 234,000 Chinook salmon and 5,217 steelhead passed over the dam. However, even when the runs are this big they are composed primarily of hatchery fish, which are not protected by law.

It is difficult to figure out just how many of the fish eaten by the sea lions were wild. The numbers differ depending on who’s reporting them. Oregon Department of Fish and Wildlife estimates that 15 to 23 percent of fish consumed at Bonneville Dam are wild Chinook salmon and steelhead, and NOAA puts the figure higher at around 33 percent. But Wild Fish Conservancy, an organization opposed to the sea lion removal program, estimates that just over 2 percent of wild Chinook passing through Bonneville dam each year are eaten by sea lions, compared to a 22 percent mortality associated with the Columbia River dam system. (They did not have an estimate for how many steelhead the sea lions killed.)

Nonetheless, some wild spring Chinook salmon runs are so fragile that fish biologists feel lucky if even 100 make it over the dams to their natal spawning grounds. Since Oregon and Washington state fishery managers prefer to cover all of their bases, they regard removing sea lions as an important component of their efforts to protect the fish.

“As biologists, we don’t like to remove the animals,” says Robin Brown, Oregon Department of Fish and Wildlife marine mammal research leader. “But we have to manage for the most valuable population and that is the wild fish…. To put it into perspective, we are removing a very small number of California sea lions out of an extremely healthy population.”

Since 2008, every year the states of Oregon and Washington and the Columbia River Inter-Tribal Fish Commission have been allowed to haze, and if necessary, euthanize up to 92 California sea lions that are deemed to be chronically eating salmon and steelhead at Bonneville Dam. Offending animals are captured in live traps and then given lethal injections. In 2015, biologists euthanized 30 California sea lions and sent two to the Queens Zoo in New York. Three more sea lions were killed in trap related accidents. The number of culled sea lions ranges from about 15 to 30 each year. Authorization to haze and euthanize sea lions is given by the National Oceanic and Atmospheric Administration under a provision of the Marine Mammal Protection Act, and is subject to renewal every four years. Brown says there is no way to measure whether the program benefits wild fish populations, but it is assumed to help to some degree.

The thing is, fish and wildlife managers tend to focus on whole populations and regard individual animals as expendable for a greater good. But they are increasingly dealing with a public that values individual animals and is concerned with how they are treated, as was dramatically exemplified last July by the international outrage over the shooting of Cecil the lion by an American trophy hunter in Zimbabwe. People are also asking serious questions about whether there are other, nonlethal ways to deal with wildlife conflicts, such as the nonlethal deterrents used to keep wolves away from livestock or the use of birth control to manage wild horse populations.

“What we have here is the idea of killing in the name of conservation,” says Michael Nelson, professor of environmental ethics and philosophy at Oregon State University’s School of Forestry, who has written extensively on the subject, and on the ethics of hunting wolves in particular. “If animals don’t matter very much, then you can say: ‘We’ll kill a few of them and see if it does what we think it will do.’”

“As people become more involved and understand how the [wildlife management] system is used, they may see it as a temporary solution that avoids the fundamental problem,” Nelson says. “Within the scientific community we need to sell that what we do will work.”

On the lower Columbia River, another program intended to help steelhead and salmon populations appears to fail on that count.

Cormorants, native to the Pacific Northwest, are fish-eating birds whose diet includes young salmon and steelhead. As with sea lions, they are often accused of contributing to declining wild fish populations. Though protected by the Migratory Bird Treaty Act of 1918, which makes it illegal for anyone to kill the birds without a permit, resentful fishermen occasionally shoot them illegally anyway.

Double-crested Cormorantphoto by Amanda, on FlickrLast year the Audubon Society discovered that high-level employees of the Fish and Wildlife Service had suppressed research by its own scientists, as well as by the US Geological Survey, that had found that killing cormorants on Oregon’s East Sand Island, would provide no benefit to wild fish populations.

Oregon’s East Sand Island, near the mouth of the Columbia River, is a 62-acre natural sandy island that has been enlarged by the Army Corps of Engineers, which manages it, and hosts the largest nesting colonies of double-crested cormorants in the world. The island’s 2013 cormorant breeding population was estimated at 15,000 breeding pairs.

Wildlife agencies had been hazing the cormorants, mainly by chasing them off by high-speed boats for a number of years, but in 2014, the Army Corps began taking public comment on a plan to reduce the population by killing about 11,000 of the birds on East Sand Island and destroying roughly 26,000 nests over four years. The stated objective was to reduce the number of endangered juvenile Snake River steelhead eaten by cormorants, estimated to be about two million a year.

Opposition by conservation groups and the public wasn’t enough to stop the plan. In April 2015, the Army Corps received a depredation permit from the Fish and Wildlife Service to kill the protected birds, and from May to October last year, agents from the federal Wildlife Services shot 2,346 cormorants and oiled 5,089 nests to prevent embryos from developing. Gunners equipped with rifles and night vision goggles shot the birds at night from towers on the island, as well as from boats on the river during the day.

Acting on a tip after the killing started, the Audubon Society of Portland, which has spearheaded opposition to the cormorant killing program, got a court order requiring the Fish and Wildlife Service to turn over emails and other documents related to the permitting decision. What Audubon discovered was that scientists from that agency and the US Geological Survey had concluded that killing the cormorants would provide no benefit to the fish, and that high-level employees of the Fish and Wildlife Service had suppressed that information throughout the public review process.

In 2014, Fish and Wildlife Service and USGS researchers completed a report that looked at survival data from tagged Snake River steelhead, as well as the number of tagged adult steelhead that survived their ocean life stage and returned to freshwater to spawn. What the researchers found was that the number of juvenile steelhead eaten by the double-crested cormorants did not reduce the population because if you took cormorant predation out of the equation, those fish would become vulnerable to other predators. The same number of fish would still be lost. The researchers also determined that killing cormorants would not increase the number of steelhead returning to spawn – the more important number for wild fish recovery. Furthermore, the researchers estimated that 50 to 90 percent of juvenile fish in each run were killed while trying to make it through the several dams on the Columbia River. In other words, unlike the fish eaten by cormorants, the juvenile fish killed by the dams would have otherwise survived to reach the sea. Not only would killing cormorants have no effect on overall juvenile fish survival, they concluded, but it is the dams that are radically reducing the number of young steelhead and salmon that make it to the ocean.

“It was the worst kind of scapegoating,” says Bob Sallinger, conservation director for the Audubon Society of Portland. “The idea that they’ll kill 15 percent of the West Coast population of cormorants while the agency’s scientists were telling them that it wouldn’t have any effect is unconscionable.” The Audubon Society of Portland, along with four other conservation groups, has brought a lawsuit to stop the killing campaign, and is calling for a government investigation of the alleged cover-up. A ruling on the suit is expected this spring.

A similar scenario has played out in Idaho between ravens, which are protected under the Migratory Bird Treaty Act, and struggling sage grouse populations. While sea lions and cormorants have become scapegoats for large dams in Washington, ravens may be taking the fall for ranching in the mountain West.

According to a 2014 study by the Wildlife Conservation Society, US Geological Survey, and Idaho State University, there has been a significant increase in common raven numbers in the sagebrush ecosystem over the past 40 years. The increase is mainly due to habitat fragmentation and the proliferation of tall, human-made structures, particularly power transmission towers, which provide additional raven nest sites. The study also speculates that the increase in raven populations is increasing predation on sage grouse nests.

photo of a Sage Grouse (Centrocercus urophasianus)photo by Ron Knight, on FlickrIn 2013 the Idaho State Legislature authorized the culling of 4,000 ravens to help stave off the precipitous decline of greater sage grouse populations.Raven eat sage grouse eggs. But some environmentalists contend that killing ravens is just a way to avoid dealing with a major threat to sage grouse – livestock grazing.

Greater sage grouse populations, in turn, have been declining precipitously throughout their range in sagebrush country, victims of habitat loss and degradation from human activities, especially energy development and livestock grazing. From an estimated historical population of as many as 16 million, sage grouse numbers have declined to about 425,000. Between 1999 and 2005, the Fish and Wildlife Service received eight petitions to list the greater sage grouse under the ESA, but the agency decided last year that listing wasn’t warranted.

To prevent a future listing and the potential economic disruption it could cause, states within the sage grouse’s range have meanwhile been developing their own plans to help the birds. The Idaho Fish and Game Commission decided that reducing the raven population would be one of the components of the state’s sage grouse recovery plan. “There is no question that raven numbers have increased drastically in the West and the Great Basin,” explains Don Kemner, state habitat manager for the Idaho Department of Fish and Game. “Ravens eat sage grouse eggs and chicks and part of the loss of sage grouse is related to that.”

In 2013 the Idaho State Legislature authorized $100,000 for the agency to kill 4,000 ravens. Initially, the federal Wildlife Services was going to do the job, but after it got bogged down in writing an Environmental Assessment, required of federal agencies, Idaho Fish and Game, which has no such requirement, conducted the killing campaign. With a Fish and Wildlife Service permit to kill protected ravens, state biologists shot ravens and destroyed nests in 2014. Because ravens are scavengers, in 2015 biologists set out chicken eggs laced with DRC-1339, an avicide that causes death from uremic poisoning and organ damage, in two areas of southern Idaho. It’s not yet clear whether the cull has had the desired effect. After Idaho’s sage grouse count is taken this year, state biologists will look to see if there has been an increase in bird’s numbers where ravens were poisoned before continuing the program.

Wildlife managers have to deal with a public that is concerned about individual animals.

Wildlife advocates had rallied against the plan but were unable to stop it. Ken Cole, Idaho director for Western Watersheds Project, says killing ravens is just a way to avoid dealing with a major threat to sage grouse – livestock grazing.

“The big problem is that livestock are removing the grass that sage grouse need to hide in,” Cole says. Sage grouse build their nests under sagebrush, which is often surrounded by grass. The grass hides the nest from predators. “That’s the first thing the cattle eat,” he says. “So much of the range has been depopulated of grass growing around sagebrush.” This makes the nests more vulnerable to being spotted by ravens. “Rather than attending to that, they want to kill the ravens,” continues Cole, whose group regularly opposes federal cattle grazing policies. “Cattle is king in this state and many groups can’t or won’t challenge cattle grazing on public lands.”

Another showdown, this one between barred owls and spotted owls in the Pacific Northwest, calls into question the long-term viability of these lethal conservation programs. Since the early 1900s, barred owls, which are protected under the Migratory Birds Act, have slowly expanded their range westward from the eastern US and Canada. They now inhabit virtually all West Coast habitat of the northern spotted owl, where they outcompete spotted owls for nesting territory and food. Biologists believe that, combined with habitat loss due to logging in the region, the barred owl’s expansion and dominance threatens the long-term existence of the spotted owl, which is listed as threatened under the ESA.

Beginning in 2013, the Fish and Wildlife Service began shooting barred owls in three areas of California, Washington, and Oregon as part of a four-year study to see if reducing their numbers would help northern spotted owl populations rebound. As of November 2015, the agency had killed 378 barred owls. If successful, the plan is to launch the program on a more widespread scale.

Eric Forsman, who studied northern spotted owls extensively for years as a wildlife biologist with the US Forest Service, is skeptical about the idea that killing barred owls can help northern spotted owls. “I don’t see it as a long-term solution,” he says. “You would have to do it forever and when you stop, the barred owls will come back.” Forsman notes that a perpetually ongoing control program would be tremendously expensive, impossible to conduct in remote areas, and in the long-term, probably won’t make a difference to the owls’ survival. “I’m somewhat pessimistic,” he says.

Back in 2013, during the International Wolf Symposium in Duluth, Minnesota, well-known conservation biologist and wolf expert Luigi Boitani pointed out that North American wildlife managers reach for the lethal option when dealing with wolves far more quickly than their European counterparts. That holds equally true for other wildlife too: Animals that are perceived as a problem, or just get in our way, are often killed as the first resort. Now that policy has been extended to protected animals, even though many of these culls are proving to be both ineffective and unsustainable. Unfortunately, lethal action is so ingrained in wildlife management in our country today that, as with cormorants on the lower Columbia River, even when science shows it won’t help, agencies push ahead with their plans anyway.

The case of the owls, meanwhile, shines a light on yet another aspect of wildlife management: the ethics of human intervention. Biologists haven’t been able to ascertain if the barred owl invasion is caused by human alteration of the environment, including intensive logging, or by a natural range expansion of the barred owl. “If you are a hardcore scientist and it’s a natural event, you have to say that this has happened a million times in the history of the Earth with one species outcompeting another into extinction,” Forsman says.

That’s the ultimate conundrum: Human impact on natural systems is now so profound that it can be difficult to parse how much we can ultimately do to fix the problems we cause, or in some cases, whether we should attempt a fix at all. In the case of wildlife management, given all these uncertainties, how can we decide which animals should pay the price for conserving others? And are such decisions ethically defensible? As environmental ethicist Michael Nelson points out, “As people push for more ethical treatment of wildlife, the collective versus the individual are beginning to collide with each other.”

Perhaps that’s a good thing.

The public outcry over Cecil the lion’s killing in Zimbabwe last year prompted nearly 50 airlines to ban transporting lion trophies, and helped speed up the Fish and Wildlife Service’s decision to designate some African lion populations as threatened under the ESA, limiting the import of lion trophies to the US. Though the circumstances under which Cecil was killed are vastly different from the ones under which sea lion, cormorant, and barred owl slaughters are being carried out in the US, the global outrage at the lion’s death highlights how a focus on the individual can help a species as a whole.

Maybe more public pushback on killing individual sea lions and cormorants as “wildlife management” will force us to rethink the presence of dams and other factors that do far more injury to wild salmon. If ravens and sage grouse are equally valued, then we must reconsider our haste in choosing lethal management strategies, and more seriously address the land uses that threaten sagebrush habitat. And as humans increasingly affect the ecological function of the planet, there may be times – as perhaps ultimately with the northern spotted owl – when all we really can do is let go.

You Make Our Work Possible

You Make Our Work Possible

We don’t have a paywall because, as a nonprofit publication, our mission is to inform, educate and inspire action to protect our living world. Which is why we rely on readers like you for support. If you believe in the work we do, please consider making a tax-deductible year-end donation to our Green Journalism Fund.

Get the Journal in your inbox.
Sign up for our weekly newsletter.

Subscribe Now

Get four issues of the magazine at the discounted rate of $20.