Owl Wars

The latest conservation conflicts pit one species against another. To save an iconic bird in the Pacific Northwest, the government is taking no chances—and no prisoners.

On a hot, still afternoon in early June, Chris McCafferty stepped off an overgrown forest road and plunged into the dense, moss-covered woods of Oregon’s Coast Range. Wearing jeans, suspenders and a backpack loaded with live mice, the shaggy-haired biologist traversed a steep slope, stepping over fallen branches and past thorny salmonberry bushes. There were no trails to guide the way, but McCafferty moved quickly on familiar, if precarious, terrain. Over the past 24 years, the 46-year-old has spent many days and many nights monitoring the region’s Northern spotted owls—a wise-eyed puffball of a top predator that is also a longstanding icon of the Pacific Northwest’s ancient forests.

When McCafferty started studying spotted owls, first for the U.S. Forest Service and then as a biologist at Oregon State University in Corvallis, the round-bellied birds, which stand about a foot-and-a-half high, appeared wherever there was habitat that would support them: mostly vast and undisturbed groves stocked with centuries-old trees. As time went on, though, their populations plummeted. Meanwhile, numbers of barred owls—a species that is slightly larger, and striped rather than speckled—quickly soared. Today, with enough evidence to link those trends, it’s clear that barred owls are pushing spotted owls out of their already shrunken territories—and possibly toward extinction. To prevent that from happening, the U.S. Fish and Wildlife Service has launched an experiment to test an unsettling management strategy: killing one type of owl to save another.

After nearly a decade of planning, the first large-scale, federally funded experiment to save spotted owls by killing barred owls is ramping up in four study sites from California to Washington. One of those sites is in Oregon’s Coast Range, where McCafferty’s trek in early June came on the heels of one of the experiment’s first major pushes. Last winter, United States Geological Survey biologist David Wiens and his team killed 244 barred owls in the area, where the spotted owl population has shrunk from 110 territorial pairs in the early 90s to 14 today.

With a plan that could end up killing thousands of barred owls in all four sites over the next few years, the experiment is the latest development in a series of owl wars that have persisted for decades. As bodies pile up, the plan is refueling the flames, highlighting the often-absurd decisions humans make about which animals matter most, and inviting new scrutiny of the god-like role we assume in deciding what should stay and what should go on a changing planet.

Killing animals that are cute, fluffy, or charismatic is a harder sell, even if the animals are raising all sorts of hell.

McCafferty’s hope that June day was to find not just the pair of spotted owls he had seen a few weeks earlier, but also a nestling or two. Already anxious because his team had recently found an ominous barred owl feather nearby, he hiked for 15 sweaty minutes before pausing upslope from a 400-year-old Western red cedar and a Douglas fir with a broken top, where he knew the pair had built a nest. He lifted his fingers to his lips and let out a two-toned, squeaky whistle. With a quick flap of wings, the resident female landed on a stump about 40 feet away. “Hi there,” McCafferty said. “We were getting a little worried.”

With a gloved hand, he grabbed a brown mouse out of his pack and dangled it by its tail over a fallen tree. If the owl had nestlings, she should take the meal straight to them. But as soon as McCafferty let the mouse go, the owl swooped over, grabbed it, went back to her stump, and ate it. McCafferty—a Virginia native with sharp cheekbones who left the sprawl of suburban Washington D.C. to seek a job working with birds in rural Oregon in 1992—grasped for explanations. Maybe she was extra-hungry and needed to fill her own belly before she could feed her young. Maybe she just hadn’t adjusted to her new parenting routines. Maybe the heat was making her lazy. She let out a quick hoot, but it seemed to McCafferty she would’ve put more effort into it if she were calling to her young.

“I want to hold out hope that she’s still got young out here,” he said. “You always want to try to convince yourself there might be hope. But it kind of doesn’t look good.”

Owl Distribution in the US/Canada

     Barred Owl
     Spotted Owl

Nobody knows for sure why barred owls expanded beyond their original range in the northeastern United States, but birders’ notes document a westward march, starting around 1900. By the 1930s, the birds had reached the Rockies. In 1959 came the first West Coast sighting in British Columbia. In the mid-’80s, a biologist working on Mt. Baker in Washington State noticed barred owls in some of the sites where he had long been tracking spotted owls. Eventually, the intrepid predators landed in California. Their presence was a novelty at first. McCafferty remembers seeing his first barred owl in Oregon in 1992. “In retrospect, we should’ve all realized this was the beginning of something disastrous,” he says. “We were young and dumb.”

While barred owls continued to surprise curious bird-watchers in the West for years, their appearance didn’t at first seem connected to the rapid decline of spotted owls, whose populations were taking a nosedive in the 1980s. Native to the Pacific coast, from southwestern British Columbia to northern California, spotted owls dine on flying squirrels, wood rats and other rodents that live in mature forests, and they are highly sensitive to changes in their environment. As logging encroached and old-growth forests fell, spotted owls became a lynchpin in battles that pitted conservation groups against timber companies, and plunged Americans into a searing debate about the relative value of animals and jobs. The owls became a conservation icon, eventually motivating the 1994 adoption of the Northwest Forest Plan, which laid a path toward compromise by setting aside protected reserves and allowing for both logging and species protection on federal lands.

By the mid-’90s, though, growing numbers of barred owls were increasingly cramming into territories, including those in pristine old-growth stands, that had long been occupied by their spotted cousins. The trajectory of change was suspicious, says Robin Bown, a wildlife biologist at the U.S. Fish and Wildlife Service in Portland. As barred owls moved south, spotted owl numbers fell, and that trend continued on down the coast.

“I believe if we messed up the system, we’re responsible for fixing it.”

—Robin Bown, USFWS

Not only were barred owls starting to seem like a real threat, but to some observers, their arrival in the Northwest reeked of human influence. It’s a point that remains contentious—and one that’s crucial to discussions about our duty to fix the problem. According to one hypothesis, barred owls started their westward expansion because of changes that swept the plains around the turn of the 20th century, including a homestead deal in the late 1800s that gave pioneers extra land if they planted trees. Gradually, the Midwest was transformed from prairie to patches of woodlands, providing enough refuges for opportunistic barred owls to slowly make their way across the country.

It’s possible that barred owls would’ve crossed the country regardless. But most owl experts now think that, at the very least, settlement of the Great Plains gave barred owls stepping stones for the journey. Since spotted owls were already being battered by the destruction of old-growth forests, the arrival of barred owls in the Northwest could have made for a double whammy of human influence, Bown says. In her view, we need to admit culpability and right our wrongs. “I believe if we messed up the system, we’re responsible for fixing it,” she says.

What is increasingly clear is that barred owls are adaptable colonizers, if not outright bullies. For one study, Wiens’s team put radio tags on 29 spotted owls and 28 barred owls in western Oregon to follow their every move. Results, published in 2014, showed that barred owls are bad for spotted owls in just about every way, including family planning. The closer spotted owls lived to barred owls, the less likely they were to produce young.

It’s easy to see why. Barred owls are bigger and more aggressive in defense of their territories; sometimes they even attack people in parks. Unlike spotted owls, barred owls will eat almost anything, including salamanders, crayfish, crickets, worms, and small birds. And they’re more tolerant of crowding. Wiens frequently sees two or three pairs of barred owls in territories that used to be claimed by just one pair of spotted owls.

The power dynamic is not going well for spotted owls. In a study published earlier this year, scientists documented a steady decline of about 4 percent per year in sites around Washington, Oregon, and California. Overall, from 1985 to 2013, spotted owl numbers dropped as much as 80 percent in some areas of the Pacific Northwest. Barred owls have surpassed northern spotted owls in numbers throughout their range. “Every time biologists have hoped there was some situation where barred owls would do poorly and spotted owls would do better, we have not found any,” Bown says. “It’s becoming more and more alarming.”

There is at least one exception: In a small plot of private land in northern California, spotted owl numbers have been holding steady—ever since biologists started killing barred owls there seven years ago.

Back in the Oregon forest, McCafferty pulled out a second mouse for the owl, whose beak was stained with blood from eating the first. Now that she’d had a snack, he hoped she would bring this one to her nest, finally revealing that there were, indeed, babies. Again, he placed a mouse on a log. Again, the owl swooped in and grabbed it. But again, she did not fly to the treetops, instead settling on a nearby stump, killing the mouse and caching it in the tree for later. She did the same with two more mice. Then she stared at the biologist, a stoic competitor in a blinking contest that began 11 years earlier, when McCafferty caught and tagged her with two ID bands on her ankles at a spot about 25 miles away. “I’ve got history with her,” he said.

The bird seemed both acutely aware of the people looking at her and intensely engaged with McCafferty in particular. She occasionally shifted on her perch like a posing teenager, revealing a personality typical of spotted owls, according to biologist Lowell Diller. Diller became engrossed with the birds in 1989, when he moved from an academic job in Maryland to work as a consultant for a northern California timber company, now called Green Diamond Resource Co. With spotted owls about to be listed under the Endangered Species Act, the company had an imminent problem: Its land was teeming with the birds.

Diller’s first task was to survey the property for spotted owls. He quickly fell for the animals, which are sharply intelligent, charmingly interactive and mesmerizing to behold. “It’s hard for a biologist who cares about animals to study spotted owls and not fall in love with them,” he says. “They’re amazing birds. They’re icons of mature forests. They’re so charismatic.”

His findings, which came out just as the listing decision was being made, were surprising. As with all things owl at the time, they were also contentious: spotted owls were doing fine in Green Diamond’s managed redwood forests. Conservationists reeled at the results, fearing they would give loggers free reign to decimate ancient forests. On the flip side, many local residents worried that the quest to save owls was going to rob people of jobs. As the situation became increasingly politicized, Diller’s personal life suffered. Once a revered professor, he was blindsided by the sudden prejudice he faced. He was accused of being a “biostitute”—selling out to his employer, willing to say anything for money. One salesperson at a local camera store refused to help him when he explained why he needed to take photos of the treetops. “She said, ‘Oh, you’re that kind of biologist,’ and she turned and walked away,” Diller recalls. “She left me standing there and wouldn’t sell me camera equipment because I worked for a timber company.”

“It has become clear that, without management intervention of some kind, spotted owls will be lost in most if not all portions of their range.”

—David Wiens, USGS

Those ruffled feathers had mostly settled by the time Diller got a call, 17 years later in 2006, from Jack Dumbacher, a molecular geneticist at the California Academy of Sciences in San Francisco. Dumbacher had been talking with Fish and Wildlife officials about trying some barred-owl removal experiments to find out whether the birds were pushing spotted owls out or simply filling in the spaces left behind by the spotted owl declines. In an early test, they removed a few barred owls from Oregon’s Klamath National Forest. But public opposition quickly stopped the effort, and the wildlife officials introduced Dumbacher to Diller instead. On Green Diamond’s private redwood forests, they would be able to circumvent some of the legal and political pressures that were likely to hold up their work on federal lands. Working for a museum, Dumbacher could also get permits to kill as many as 20 individuals of a species for his collections. Diller joined Dumbacher in the field over two cool, foggy nights in May 2006, during which Dumbacher shot three pairs of barred owls. Diller couldn’t watch. “It seemed so wrong,” he says. “I had to turn away.”

It was harder to ignore what happened next. In every place where Dumbacher had removed barred owls, spotted owls appeared, often after long absences. One banded individual that hadn’t been seen in three years greeted Diller at its original roosting site just 13 days after Dumbacher’s visit. It was powerful, if anecdotal, evidence that Diller thought was worth testing with a controlled experiment. Soon, he was pulling the trigger himself, eventually killing more than 80 barred owls over the next few years in three treatment areas on Green Diamond land near the Pacific coast, in California’s Humboldt and Del Norte counties.

The results were dramatic. Compared to similar plots of land where spotted owl populations continued to decline, in the treatment areas, the birds rebounded. Although it was a small pilot study in a region where barred owl numbers are relatively low, the findings offered support for the new experiment to try removals both on a larger scale and in other, more typical, parts of the owls’ range throughout Washington and Oregon.

“The pressing question is whether similar results can be obtained in other conditions,” says Wiens, the USGS biologist, who is in charge of removals in the Coast Range region, “because it has become clear that, without management intervention of some kind, spotted owls will be lost in most if not all portions of their range.”

Killing animals in the name of conservation has become common practice, both in the U.S. and abroad, often in cases where invasive species have wreaked havoc on ecosystems. In recent years, government agencies have killed, issued permits to kill, or considered killing: ravens to save desert tortoises, hawks to save Hawaiian crows, mute swans to protect New York’s ducks, geese and other water fowl, and sea lions to protect salmon, which are also getting assistance from the systematic killing of cormorants, Caspian terns, and northern pike.

Some culling efforts have helped, like the removal of parasitic cowbirds in the Midwest to protect willow flycatchers, Kirtland’s warblers and other birds. Others have been disastrous, like the removal of feral cats in Tasmania, which only caused more cats to creep in. Many have been controversial. And while it’s not so hard to convince people to accept the killing of dangerous or unappealing invasives, like Burmese pythons in the Everglades (which has taken on festival-like status), killing animals that are cute, fluffy, or charismatic is a harder sell, even if the animals are raising all sorts of hell.

When the U.S. Fish and Wildlife Service started to consider an experiment to kill barred owls on federal lands, it was clear they would need to manage emotions as much as they needed to manage the animals. “We knew any kind of removal of something as charismatic and fuzzy and brown-eyed as a barred owl, no matter how good the data, was going to be uncomfortable for people,” says Bown, the Portland-based FWS biologist.

To preempt the fallout, the FWS went on a public-engagement offensive in 2009, organizing workshops in Portland and Eugene with a diverse list of guests that included representatives from conservation groups, tribes, timber companies, and animal welfare organizations, as well as scientists and a bioethicist named William Lynn. Participants discussed a variety of non-lethal alternatives—sterilizing barred owls, luring them away with food, capturing them to keep in captivity. And they discussed the potential downsides of those alternatives, including stress for the animals and costly or unrealistically labor-intensive work for the researchers. Bown had already conducted a nationwide search for facilities that would take captive barred owls and found homes for fewer than 10 individuals.

Lynn, who is based at the Marsh Institute at Clark University in Worcester, Massachusetts, led the ethics conversations, aiming to help the people involved use logic instead of emotions to make decisions. Ethics reviews force a hard look at moral values—like an aversion to killing animals or an affinity for native species. In the style of a Quaker meeting, Lynn listened to everyone and then articulated what he heard them coming to agree on.

Rigorous ethical analyses are common in biomedical studies, but this was the first time one was applied to a federal wildlife management decision in the U.S., Lynn says. And that marked a profound shift toward recognizing the potentially devastating impact of environmental decision-making—and the tough position that ordinary scientists face when given the task of choosing between life and death. “These are absolutely tragic decisions—one way or another, there’s tragedy involved,” says Michael Paul Nelson, an environmental ethicist at Oregon State University in Corvallis who was not involved in the meetings but has watched the issue develop. “It’s not clear that people who have to make these tough decisions are trained or capable of doing it, and that’s putting them in a weird position.”

The Oregon meetings lasted for days, and Lynn noticed several pivotal moments, when participants on different sides of the issue realized they actually shared a deep caring for animals and that nobody was thrilled with the choices. In the end, consensus emerged that the removal experiment was worth trying as a stopgap measure, to prevent spotted owls from disappearing in the wild. Even the ethicist was moved by the experience, and came to realize that doing nothing would likely mean that spotted owls would go extinct. “I went in profoundly skeptical,” Lynn says. “This changed me.”

The official plan designates four study areas. During the summer and fall, research teams at each site conduct surveys to get a barred owl head count. Come winter, they then try to remove as many of those birds as they can. The killing must be done as humanely as possible, via a quick and clean shot and only when birds are in close range. Nestlings and parents with dependent young must be spared. “People were unwilling,” Lynn says, “to go in and massacre a family.”

Wiens, who is 47, uses a 12-gauge shotgun that was designed by Diller’s brother. It is equipped with a flashlight, red laser spotter and four-foot long silencing extension. Standing a lanky 6 feet 6 inches tall with a hopeful, kid-like face, Wiens had never held a gun before he went through extensive training for the experiment. The job still makes him uncomfortable. Still, it didn’t feel right to lead the study if he couldn’t do the dirty work himself. “I never envisioned myself doing this sort of thing,” he says. “I also believe that, to run an experiment like this, I have to know what it’s like. I still do it a limited amount because it’s pretty disturbing to me.”

It will take at least four years of data to know if the experiment is making a dent, Wiens says. In the meantime, he tries to focus on the good that stands to come from it. He plans to send some of his barred owl kills to universities, museums, and other facilities, including the Cal Academy, where Dumbacher and colleagues are investigating the effects of rodenticides on the birds and using genetic analyses to reveal new details about both owl species and the interbreeding that sometimes happens between them. (It’s another odd twist that adds yet more questions about what we should do when natural selection escapes our control.) The experiment might also benefit other animals that have been decimated by barred owl invasion, such as frogs, salamanders, and other owl species. Disrupted food webs are often overlooked with so much focus on birds.

Controversy over the plan has been surprisingly quiet, perhaps because the Fish and Wildlife Service has been so transparent about its motivations. Beneath the basic question of whether it’s okay to kill in the name of conservation, though, is a deeper conundrum that digs into the heart of the Endangered Species Act. The law was designed to preserve the diversity of life on earth—but it also mandates that listed species must be protected, no matter what. To do right by the ESA, in other words, scientists must sometimes cause harm—a paradox that may be cropping up with increasing frequency as conflicts between animals and people escalate.

By chopping nature into discrete species, the ESA also forces black-and-white thinking onto the fuzzy reality of the natural world. And that approach fails to accommodate changes that can occur with migration, natural selection, the merging of genomes through interbreeding, and other messy ecological processes—all of which are happening to owls on a national stage. If given a chance, Dumbacher says, the owls could force fresh conversations about what deserves protection and at what costs, offering an unprecedented opportunity to alter society’s deep-level thinking about how to make wildlife management decisions. What if a heart-tugging story about owls could get ordinary citizens to finally care about the gritty details of how evolution and conservation work?

Still, yet to be determined is how to define success, and how to know when to stop. As large scale as it is, the federal removal experiment is still relatively narrow in scope. It is not intended to wipe out barred owls from the West completely or to kill barred owls forever. Instead, the goal is to test whether barred owl removal in some areas will enable spotted owl populations to rebound. It may just be the first step in determining whether both species can co-exist, at least until biologists can find a more sustainable way to manage the situation. The project is capped by a 10-year timeline. Stopping early is always an option. Wiens suspects five years will be enough to know if it’s working.

Not everyone is on board, including Eric Forsman, the biologist who initially raised concerns about spotted owls in the 1970s and has argued vocally that the killing, even for a finite period, is likely futile. Another concern is that shooting barred owls will take yet more attention away from the habitat loss that slammed spotted owls in the first place, says Shawn Cottrell, northwest director of Defenders of Wildlife in Seattle and former executive director of the Seattle Audubon Society. His organization supports the federal experiment, he says, but he doesn’t want to see barred owls become a scapegoat for everything else that’s going wrong in the environment. “If we think we can solve the problem just by dealing with barred owls,” he says, “it’s not going to work.”

The uncertain finish line raises another lingering concern: if the experiment doesn’t work, will thousands of animals have died in vain? “There is an absolute absurdity to it, maybe a whole set of absurdities, like nested layers of absurdity,” says Nelson, the Oregon bioethicist. “Do we really believe we can fine-tune the world so much that we can predict how all these things will interact? Haven’t we learned that lesson?”

“If we think we can solve the problem just by dealing with barred owls, it’s not going to work.”

—Shawn Cantrell, Defenders of Wildlife

Three days after his first failed attempt to find the young spotted owls, McCafferty returned to the same spot and checked again. His expectations were low, but this time, the female grabbed the mice and immediately swept them away, taking the rodents back to the young, recently fledged owls. One sat high in a big-leaf maple. The other was huddled lower down in a vine maple. The fluffy owlets are the only two known young to come out of the nesting season in the study site this year, and their prospects of making it to adulthood are anything but certain: On two subsequent visits, McCafferty’s team has seen only one of the two.

The little owl family is just one data point in a long-haul study with a lot of agonizing work still ahead. But McCafferty sees it as a positive sign, especially as good reproductive years for Oregon’s spotted owls have become fewer and farther between. By settling down and rearing young this season, he says, these two owls demonstrated a transformation from just a year ago, when the female never showed up in the study area at all, and the male appeared all over the place. The pair was clearly in no shape to start a family then. But now, they’ve given their species at least one more fighter.

Perhaps the hatchings are a lucky blip in a sea of declining numbers. McCafferty clings to a more hopeful possibility: Maybe the spotted owls in the Oregon Coast Range site are feeling liberated by their newfound freedom from barred owls. “I do see that as a symbol, that there are some possible early signs of success,” McCafferty says. “That there’s a future here.”

Header image of adult spotted owl in a Pacific Northwest forest by Gerry Ellis/Minden Pictures.

Emily Sohn

Emily Sohn is a freelance journalist in Minneapolis whose stories have appeared in National Geographic, Outside, The Washington Post, The New York Times, Nature, NPR, and many other publications.

Laura Fravel

Laura Fravel is a Portland-based filmmaker and photographer who is passionate about creating conversations around environmental and social issues. Her worked has appeared on National Geographic, Smithsonian, PBS, and The New York Times, among others. You can see more of her work at

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