A new generation of unruly wildlife has some experts wondering whether what we’re missing isn’t so much habitat as adult supervision.
By Dawn Stover October-December 2009 (Vol. 10, No. 4)
On a dark night last fall, 11-year-old Joe Hess was playing a backyard game of hide-and-seek with his younger brother and two friends near Grand Coulee Dam in eastern Washington. Lying face-down in the grass, Joe thought he saw Magellan—a huge housecat that lived next door—out of the corner of his eye. When the cat pounced on the boy’s head, Joe leaped to his feet and yelled, “No!” But it wasn’t Magellan—Joe was staring at a cougar that looked a little bigger than a German shepherd.
Joe slowly backed away from the animal, then turned and ran inside the house. He had a few shallow scratches but was otherwise unharmed. The wildlife agents who responded to the scene told Joe’s parents that the cougar was probably a young animal, about a year old, that had recently left home to begin life on its own. Joe’s lack of serious injuries might have meant the cat was just playing with him. Or maybe it was simply an inexperienced predator, unsure of whether a boy belonged on the menu.
Cougar encounters like this one are becoming increasingly common in the United States. Most people assume that’s because cougar populations are growing, or because the big cats are coming into closer contact with the expanding web of human suburbs. But Robert Wielgus, director of the Large Carnivore Conservation Lab at Washington State University, believes there is something far more complex at work.
In research that has stirred controversy in academic and policy circles, Wielgus argues that poorly designed hunting policies might be triggering an increase in cougar-human conflicts. As hunters kill disproportionate numbers of mature, male cougars, a generation of disorderly teenage cats is taking over their turf. Without adults to keep them in check, Wielgus believes, the unruly juveniles are more likely to run afoul of humans, livestock and pets.
Cougars aren’t the only species with troubled teens. Off the Florida coast, small sharks attack swimmers more often than large ones do. In Africa, orphaned male elephants have killed humans and rhinoceroses. And in the southwestern U.S., young California condors have destroyed roof tiles and torn off windshield wipers after being released into the wild. The naughty condor behavior decreased markedly when researchers began a “mentoring” program that houses puppet-reared chicks with an adult condor for about a year before they are released. And the marauding elephants calmed down when older bulls were introduced. In a provocative theory that suggests adolescent wildlife may be surprisingly similar to human teenagers, some scientists believe adult supervision could be the key to better behavior for cougars, too.
“Sometimes they hiss at you as you’re climbing,” says Hugh Robinson, a University of Montana researcher who, as a graduate student, helped Wielgus track down cougars. For more than a decade, Wielgus’s research teams have been fitting the big cats with radio collars and monitoring their movements. To locate the cougars, researchers get up at 4:30 on winter mornings and set out on snowmobiles. If they find fresh tracks in the snow, the researchers bring in a houndsman with trained dogs to follow the scent and drive the cougar into a tree. Once the cat is treed, the team moves in and shoots it with a tranquilizer dart. If the cougar doesn’t then jump—or fall—out of the tree, a researcher climbs up and lowers the cat to the ground with a rope.
From 1998 to 2003, Wielgus’s team turned up some unexpected findings as they tracked a group of cougars in northeastern Washington, northern Idaho, and southeastern British Columbia. At the time, cougar populations were believed to be exploding across the U.S. This perception was driven in part by an increase in cougar attacks. Beginning in the 1970s, cougar attacks on humans went from about four per decade in the U.S. and Canada to about 18 per decade, says Paul Beier, a Northern Arizona University professor who studies cougar attacks. Although such altercations are rare compared with, say, attacks by domestic dogs—which kill about 16 Americans every year and send another 386,000 to the emergency room—they generate a lot of media coverage, which builds an outsized impression of cougars’ presence.
In Wielgus’s home state of Washington, this perception was furthered by a 1996 ban on using hounds to hunt cougars—which many believed would reduce the number of cougars killed by hunters—as well as a rising number of cougar complaints. In 1995, the Washington Department of Fish and Wildlife registered 247 cougar complaints. By 1998, that number had skyrocketed to 927.
Wielgus’s study—published in 2006, three years after the radio-collar monitoring was completed—found that the cougar population was actually declining rapidly. (1) What really struck Wielgus’s team was that they found almost no male cougars older than four years of age.
Wielgus suspected hunting policies were the culprit. Wildlife managers have long seen hunting as a way to keep cougar populations in check, placating ranchers and homeowners who worry the cats will prey on livestock or children. Wielgus thought hunters might be picking off most of the big, mature males, which make the best trophies. To test his theory, Wielgus added two more groups of cougars to the tracking program—one in a heavily hunted area and another in a comparable but lightly hunted area. In a recent study in Ecology, he and his coauthors concluded that heavy hunting indeed decimates older males. (2) Another study showed the size of the cougar population in the heavily hunted area did not change, but the population structure shifted toward younger animals. (3)
Conventional wisdom holds that eliminating large male cougars keeps people and livestock safe. But Wielgus believes this paves the way for a bigger threat: unruly young males who move in from nearby areas and, unlike mature cougars who have learned to avoid humans, don’t always mind their manners.
The life of a male cougar is not an easy one. Raised by a single mom, he is forced to leave home by the age of two. His father, who marks and patrols a territory that may include the home ranges of several females and cover hundreds of square miles, does not tolerate other adult males in the area. So the son strikes out on his own, traveling long distances in search of a new home where he can find food and females. Only about 40 percent of young males survive their first winter alone, sometimes by occupying the loosely defended fringes of an older male’s territory. A young male lucky enough to find an unoccupied territory will spend the rest of his life guarding the boundaries established by the previous occupant. “It’s like a home going up for sale,” says Wielgus. “The property remains the same; there’s just a new owner.”
These homeowners are elusive creatures. Harley Shaw, who spent 27 years as a wildlife biologist working in cougar country for the Arizona Game and Fish Department, has seen only four cougars without the help of tracking collars or hounds. But studies using GPS collars have found that cougars spend a surprising amount of time cruising the edges of suburban neighborhoods, undetected. Some biologists cite this as proof that humans and cougars can peacefully coexist. “Usually they are inclined to avoid us,” Shaw says. “If they didn’t, we would have a lot more attacks and encounters.”
Wielgus worries that these elusive tendencies are breaking down. When older males die, they leave behind an open territory that’s often within range of human settlements. The males who move in are younger, unaccustomed to humans, and—possibly—more brazen and curious. But can this really make them more likely to run afoul of people and livestock?
This question weighs heavily on the mind of Ben Maletzke, a WSU graduate student who is comparing cougar complaints from the heavily hunted and lightly hunted areas. His preliminary findings suggest that the heavily hunted area has five times as many complaints per capita, and eight times as many livestock predations, as the lightly hunted area—even though the density of cougars and livestock is about the same in both areas. Wielgus suspects that teenage immigrants in the heavily hunted area may be responsible for most of the trouble.
In other words, hunting policies that allow a disproportionate number of males to be killed may be exacerbating the very problem they set out to solve. Paul Beier’s studies of attacks on humans support this counterintuitive notion. Beier says that at least half of the cougars involved in these attacks are juvenile animals, typically around a year old. “The older ones are smarter and know how to behave better,” Beier says.
The scientists have also discovered that, in the heavily hunted area, the home ranges of the new arrivals are much larger and overlap more than in the lightly hunted area, because the animals are not old enough to maintain strict boundaries. “It’s territorial chaos,” Wielgus says. “Instead of one old cougar that keeps his nose clean, you’ve got three teenagers wreaking havoc.”
Wielgus’s ideas don’t sit well with everyone. His critics and even some of his own former graduate students are not completely convinced that age is a key factor in human-cougar conflicts. “Hunting definitely does cause an influx of juvenile males,” says the University of Montana’s Robinson, but he doesn’t yet see solid proof that juveniles are more trouble-prone than older cats. “It’s still just a hypothesis,” he says.
Maybe increased attacks have nothing to do with a cougar’s age but instead simply result from the cats’ being new to the area. In many cases, the new arrivals have been squeezed out of remote wilderness habitat and forced into areas where they are more likely to encounter humans. “There’s so much more to the equation than just being a young cat,” says Mat Alldredge, a researcher at the Colorado Division of Wildlife who is studying cougar demographics and human interactions along the Front Range. And with few cats surviving to a ripe old age, there may be no way to know whether older animals would be better behaved than youngsters. “I think humans are primarily responsible for all the interaction you see,” Alldredge says. “We’re moving into these areas where cougars and deer are.”
As a possible solution, Alldredge is testing scare tactics, which he euphemistically refers to as “aversive techniques.” The idea is to teach cougars to be apprehensive about approaching populated areas. Some of the cougars Alldredge traps and relocates are being released with a special sendoff: beanbag rounds fired from a noisy, 12-gauge shotgun. “It’s an ‘extra’ to see whether it helps keep them away” from populated areas, he explains.
A bigger fix might be to revise hunting policies in a way that ensures older, wiser males remain in the cougar population. In a recent study in PLoS ONE, University of Minnesota professor Craig Packer and his coauthors estimated that killing only males that are at least four years old would ensure that they live long enough to produce offspring and protect them from other males. (4) Perhaps there should be a minimum “catch size” for cougars, Packer says, similar to the laws that require sport fishermen to release small fish so that they can grow up to be big fish.
“You cannot manage animals like chess pieces,” says Gay Bradshaw, an expert on animal psychology and neuroscience who heads The Kerulos Center in Jacksonville, Oregon. Bradshaw has written extensively about how elephants, lions, and other species have distinct cultures that humans are only starting to glimpse. Until these cultures are understood and respected, she believes, it will be virtually impossible to live peaceably with cougars and other wildlife.
It’s a controversial idea that raises a provocative question: Instead of just eradicating “problem” cougars or other animals, should we try to understand them in the same way we understand humans who come from broken homes or violent neighborhoods?
Bradshaw has documented how witnessing a shooting—or living in daily fear of being shot—can trigger posttraumatic stress disorder in lions and elephants. These animals have the same brain structures and mechanisms that in humans are responsible for intelligence, emotion, and culture, Bradshaw says. And young male elephants seem to behave better when there are mature bulls around.
Wielgus has no doubt that cougars follow a similar dynamic, even though this makes him an outlier among his colleagues. Cougars are solitary animals, but Wielgus notes they do come into contact with each other. He believes these interactions may teach youngsters to distinguish between appropriate and inappropriate prey and behavior. In turn, Wielgus thinks it’s time to consider how hunting and other human activities can cause social chaos among these animals. Older male cougars may not be role models, says Wielgus, “but they certainly serve as a police force.”
If this seems like a bizarre idea, think of it in human terms: imagine what any community would be like if most of the adult men disappeared. We may not understand what makes 18-year-old males more likely than 48-year-old men to do dangerous things, Wielgus says, but we know that the world would be a different place if teenagers were in charge. ❧
1. Lambert, C.M.S. et al. 2006. Cougar population dynamics and viability in the Pacific Northwest. Journal of Wildlife Management 70(1):246-254.
2. Cooley, H.S. et al. 2009. Does hunting regulate cougar populations? A test of the compensatory mortality hypothesis. Ecology 90(10):2913-2921.
3. Robinson, H.S. et al. 2008. Sink populations in carnivore management: Cougar demography and immigration in a hunted population. Ecological Applications 18(4):1028-1037.
4. Packer, C. et al. 2009. Sport hunting, predator control and conservation of large carnivores. PLoS ONE 4(6):e5941.
Dawn Stover is an editor at large for Popular Science magazine and has also written for Earth 3.0, New Scientist, and Outside. She lives in White Salmon, Washington.