Doug Smith, Yellowstone National Park Wolf Project Leader interview

Recently, the Montana Pioneer spoke with Doug Smith, Yellowstone National Park Wolf Project Leader and Senior Biologist at the Yellowstone Center for Resources, about the nature of the wolves introduced to Yellowstone National Park in 1995, including the “non native subspecies” charge advanced by critics, and about ongoing research on wolves in the park.

MP: What were the genetic sources of wolves introduced into YNP—where did the existing wolf population originate?

DS: Forty one wolves were introduced to YNP in 1995. There were 14 in 1995 from Alberta, and 17 in 1996 from British Columbia, and 10 in 1997 from near Choteau, Montana. We have genetic evidence that some of those wolves went on to breed. So, 10 of the wolves that were introduced were from Montana, and 31 were from Canada.

MP: What were the main characteristics that were different between the wolves from Canada and the wolves that pre-existed here in Yellowstone, say 150 years ago? Is that known?

DS: Not really. All we have are skulls to judge it from. What we know from studying the skulls are that the wolves are essentially the same. The Canadian wolves were about 7 to 8 percent larger than the pre-existing wolves of Yellowstone. Seven to eight percent is within the variation of size difference found in wolf skulls all over North America, so the difference is statistically insignificant. It is important to compare apples to apples, so-to-speak. Pups and immature animals are smaller, and males are about 20 percent larger than females, at full size. It is important to compare similar age and gender skulls to each other. So comparing the handful of skulls that were preserved here as museum samples with over 150 skulls of wolves that have died here since they were introduced, the skulls are essentially the same, but the ones from Canada are slightly bigger.

Taxonomically (classifying in categories such as genus, species, and subspecies), you get differences between species when there are limitations on their ability to mix genetically. Wolves are stopped by nothing. They will cross mountain ranges, rivers, even pack ice. That’s how good this animal is at moving around. So what we have is this constant intermixing of genes that prevents them from becoming really different subspecies. Wolves origin-ated in North America a couple of million years ago. When glaciers connected Alaska and Russia, they crossed over into Russia. They got bigger over there. In the last 600,000 to 700,000 years differently evolved wolves have crossed back to North America in three waves. The remnants of the oldest wave of wolves returning to North America are now the most southern species, and also the smallest, Canis lupus baileyi, the Mexican wolf. The middle wave of evolved wolves returning to this continent from Asia are the gray  wolves we have here now, and the most recent are the largest, the arctic wolves.

MP: Were the wolves introduced into YNP significantly different physically or behaviorally from the wolves that were here?

DS: The short answer is no. Wolves are ecological generalists. They can live on a variety of things. We looked for wolves that were previously exposed to bison and elk. The Canadian wolves had a small percentage of bison hair in their scat, but primarily elk and deer hair. We thought that was ideal, as that is the same diet—primarily elk and deer—as we have here. The available wolves from Minnesota had no experience with mountainous terrain or herds of elk or bison. We selected wolves from the same Rocky Mountain ecosystem, with the same kind of prey, to enhance the likelihood of the introduced wolves surviving. I want to clarify the misconception that larger Canadian wolves were preying on smaller American elk [thereby reducing the elk population inordinately]. In fact, the much smaller southwestern Mexican wolf brings down elk. The elk the Mexican wolves prey on in Arizona and New Mexico originally came from Yellowstone, as did the elk in Canada. The optimal number of adult wolves necessary to bring down an elk is only four, but a pair of wolves can also kill an elk.

MP: We hear reports that there were wolves already in Yellowstone that could have multiplied without reintroduction.

DS: There were no wolves here when we introduced the current wolves in 1995. There were no specially adapted wolves [as critics have claimed] in Yellowstone that did not run in packs, or use trails or roads, that didn’t howl, and that preyed on small prey, unlike the wolves we have now. There has simply never been a wolf recorded anywhere that lives like that. Furthermore, there is no better bird dog for a wolf than a wolf itself. We had radio collars on all 41 wolves we released over a 3-year period. If there were extant wolves already on the landscape, they would have found them. The wolves we released never turned up any other wolves, dead or alive. And by the way, they rarely eat other wolves that they kill.

MP: Wolves killing other wolves is the main cause of wolf deaths in the park, correct?

DS: Yes, almost half of the 15 YNP wolves that died in 2012 were killed by other wolves. However, for wolves living outside the park, 80 percent of the wolf deaths are caused by humans, mostly by shooting them.

MP: How many wolves are in YNP now?

DS: Last year at the end of 2012 there were at least 83 wolves occupying YNP in 10 packs (6 breeding pairs). This is approximately a 15 percent decline from the previous three years when the numbers had stabilized at around 100 wolves. Wolf numbers have declined by about 50 percent since 2007, mostly because of a smaller elk population.

MP: Would the 1994 population of gray wolves that lived in Montana have naturally recovered, given the protection of the Endangered Species Act?

DS: That was a big opinion-based debate by wolf biologists at the time, led by Bob Ream of the University of Montana. In his opinion, wolves would have recovered given enough time—50, 60 or 70 years. Other people think they would not have made it. Yellowstone National Park and the five National Forests around it can be likened to a huge island. It’s the most impressive wild land we have got in the lower 48, and some people say it’s the most impressive temperate zone wild land in the world. But it’s got an abrupt boundary to it. I frequently fly over here in an airplane, and at the boundary of a National Forest, it turns into a sea of humanity. And wolves are notoriously bad at getting through seas of humanity. Wolves get shot a lot. When we were dealing with a handful of wolves, maybe 40 to 60, how many of those would have been heading this way? So far, we have not yet documented a wolf coming from northwest Montana into Yellowstone. We have documented them coming from Idaho, but that’s a lot closer and the linkages are better, primarily in the Centennial Mountains. Wolves don’t do well over huge landscapes dominated by people. By introducing wolves they were legally not a fully protected species under the Endangered Species Act. People wanted to be able to shoot them when they got into livestock, which they could not have done if they were a fully protected species.

MP: Wolves from Idaho have now invaded the original Glacier National Park wolves, right?

DS: The Idaho wolf population is now fully connected to the northwest Montana wolf population. Interest-ingly, a study of historic wolf DNA from pelts and skulls shows that over 50 percent of wolf genetic diversity was lost when the continental United States population was reduced to a few hundred wolves in Minnesota. Wolves were the top carnivores in North America. Wolves evolved to adapt to the local conditions, and they will do so again.

MP: The tapeworm cysts spread by wolves that critics rail about, what risk to humans does this pose?

DS: The Echinococcus granulo sus tapeworm was already here. Wolves didn’t bring it in. The coyotes, foxes and domestic dogs likely had it before wolves. The human health risk from tapeworms is almost nil. If anyone should have Echinococcus tapeworm it’s me. I’ve handled over 500 wolves in my career. I take their temperature with a rectal thermometer. That’s where the tapeworm eggs come out. I now wear rubber gloves, but I wash my hands in snow, then eat my lunch. I wouldn’t worry much about it.

MP: What are the primary benefits and disadvantages of having wild ranging wolf packs in the Northern Rockies?

DS: The simplest way to answer that is that there is no question that wolves made people’s lives more complicated, and that’s a good reason not to have them. Some people love them, some people hate them, and wolves are a polarizing animal. People have to spend a lot of time dealing with the controversy that comes with wolves. Life is simpler without wolves. I admit that if you are a rancher, having wolves around is worrisome. I understand that it’s not just the cows they kill; it’s the sleepless nights. I think that’s the best argument to not have them.
What’s the ecological value of wolves? I don’t know. It’s a human dominated world. We control everything. So why do we need wolves? Landscapes look the way they do because of agriculture, forestry, hunting, mining, development—all those things trump things like wolves. So you really don’t get huge ecological benefits of wolves outside of National Parks. In National Parks you do. So why have wolves on these huge landscapes where there are people? Good question. The best answer is, because people want them there. You know, there are a lot of people that don’t like wolves. There is an equally large number that do like them, because living in Idaho, Montana and Wyoming is unique and different than living in places like Illinois, Iowa and Arkansas. You have grizzly bears, you have wolves, you have cougars. And that brings in a lot of tourism dollars. Wolves and grizzly bears are the two top attractions to Yellowstone. Idaho, Montana and Wyoming are perceived as being pristine, just because of the mere existence of the three large, toothy carnivores. It makes visiting or living here more valuable and a better experience. Economics are more important than ecology when it comes to carnivore populations in Yellowstone National Park.

Right now, it’s as natural as it’s ever been in Yellowstone Park. Now we have more predators than we have ever had, which means we have fewer elk, and fewer elk means we have all these other ecological benefits, like beavers and songbirds and fishes, and generally enhanced riparian habitat, because fewer elk means less browsing of riparian habitat. So it’s a more balanced ecosystem. We only get that because we have natural densities of carnivores. As soon as you cross the park line, all the densities of those carnivores go down because humans manage them. And that is fine; it’s not a criticism. The carnivores are on the landscape. That’s the thing that the tourists like, but they are not at their normal densities that would occur if people didn’t manage them.

MP: What about surplus killing by wolves [where, for example, ranchers report wolves killing or maiming a dozen sheep in one night]?

DS: Surplus killing by wolves doesn’t really exist, per-se. We have watched wolves when they have killed more meat than they can immediately consume, and they always come back to finish the carcass unless they are spooked off by people. Hunting success rates for wolves are in the 5 percent to 15 percent range with elk. So they actually get about one in ten of the elk they go after. Eighty five percent to 95 percent of the time, the elk wins, and the wolves get nothing to eat. So, from an evolutionary perspective, if the wolves are not highly motivated to kill whenever they can, they will lose out. Of the 500 wolves I have handled, all across America, in the Midwest, Canada, Alaska, Yellowstone and Idaho, most of them are skinny beneath their beautiful fur. When I have felt their backbones and their pelvises, they usually are skinny. They are just getting by. The prey is better at getting away than the wolves are at killing the prey. So it is so hard to get dinner and when they do get a chance to kill, they kill. That’s how you get so-called surplus killing, when the elk are weak and in deep snow, wolves will kill more than they can eat. Also, defenseless sheep will be killed in large numbers because the wolves can do so. But I would argue that if the rancher didn’t come out the next day with a rifle, the wolves would eat all those sheep, even if it took them weeks to do so.

Wolves don’t kill for the fun of it, when they are likely to get their head bashed in getting dinner. We have seen 15 or more wolves that have been killed by elk, bison, deer and moose. Wolves are risk averse. They don’t want to try to kill something that’s going to get their head bashed in or their stomach kicked in, but when it’s easy, they will kill more than they can immediately eat, but those circumstances crop up pretty rarely. The wolves always cycle back to finish the carcass.

MP: What is the effect of wolves on the coyote population?

DS: Wolves kill coyotes when they approach wolf kills. Pre wolf-introduction, coyotes were living in packs in YNP, and that’s something that’s unusual. When there are wolves around, the coyotes pretty much live in pairs. Coyotes love coming in and stealing from wolves, and that got them killed. According to unpublished research, supposedly the coyote population dropped in half after the wolf introduction. Over 90 percent of the coyotes that are documented as being killed by wolves have been killed at wolf kill sites—they over estimated the wolves being meat drunk. So the coyotes quit running in packs, and went back to living in pairs, and became more wary around carcasses. The coyotes supposedly socially adapted to wolves, and their population went back to pre-wolf levels. This research is incomplete and inconclusive, but fascinating.

MP: Thank you, Doug. We appreciate this opportunity to present knowledge you have gained over the years about wolves, and at the same time address some of the contro-versies.

DS: Wolves are troublesome and controversial. I understand that. A lot of people don’t like them, but a lot of people do like them, and they make money for a lot of people. What I am really after is to get as good a quality of information out there as possible, to help the debate to be a little bit better.  The extreme anti-wolf person and the extreme pro-wolf person are always going to be problematic; they are never going to be happy. But this big group of people in the middle can come together on more than they think. If we can get an established group of facts about wolves correctly understood, I do think we can make progress in treating wolves just like any other animal, like a cougar, like a bear, like an elk. Sometimes and in some places their numbers need to be cut back, and just like any other form of wildlife, they need to be scientifically managed.

Interview conducted by Quincy Orhai for the Montana Pioneer.


The importance of predators: the Yellowstone case

A segment of the video “Predators” from “Strange days on planet Earth” (NatGeo). A very good example of how vital the role of top predators is in ecosystems is shown in Yellowstone with the reintroduction of wolves.

Bison carcass draws feeding frenzy of grizzlies, wolves in Yellowstone Park

Yellowstone Park bison, grizzlies

A grizzly sow claims a bison carcass in Yellowstone National Park last month from a male grizzly, called a boar, as her three cubs await the all-clear signal. The interaction of bears, wolves and scavenger birds played out only 400 yards across the Lamar River in mid-September.

Yellowstone Park bison, grizzlies

The sow seems to be giving the boar a cursing. A good berry crop has kept bears out of trouble with humans so far this fall, but hunting season along the edges of their habitat is a draw since hunters leave gut piles from elk and deer they’ve shot.

Yellowstone bison, grizzlies, wolves

As the sow moves the boar away, wolves sneak in on the distracted grizzly cubs.

Yellowstone grizzly and cubs

After dining on the bison carcass, the grizzly sow and cubs drink from the Lamar River.

Three cubs

It’s not unusual for a grizzly bear to have three cubs; two or three is normal.

The sow and a black wolf go nose to nose

The sow and a black wolf go nose to nose in a standoff.

In almost 20 years of shooting photographs in Yellowstone National Park, Pete Bengeyfield had never seen anything quite like an interaction that played out about 400 yards away.

Across the Lamar River near its intersection with Soda Butte Creek, a bison had died on the sagebrush-dotted prairie. Claiming the carcass was a large male grizzly bear — called a boar. As the boar ate, five wolves from the Junction Butte wolf pack circled, waiting for an opportunity to dash in for a stray morsel of flesh to satisfy their own hunger. On the edges, crows, ravens and magpies stood and flitted, awaiting their chance to clean up.

This scene in itself was impressive, but what really made the show extraordinary was when a sow grizzly and her three cubs ambled in. It was a predator-scavenger menagerie.

“The behavior was phenomenal for three days,” Bengeyfield said. “I’ve never seen anything that interesting within camera range.”

Captured on camera

Bengeyfield’s series of photos show a variety of interesting interactions among the animals: four wolves laying around the carcass as the boar stands atop the bison as if to say, “Hey, this is my bison, you better stay back;” the sow and her cubs approaching and getting an ears-back glare from the boar and two wolves in a not-so-veiled threat that they didn’t want any more competition for the food; the sow standing atop the carcass in a cloud of dust, both bears with their mouths agape, as she claims the carcass while her cubs wait to the side; the sow, mouth opened as if roaring into the boar’s ear as his back is to the camera and she stands atop the carcass; the sow appearing ready to bite the big boar in the face as he pulls his head out of the way and growls back; the sow moving off the carcass to shoo off a snarling wolf; three wolves surrounding the three cubs, who are tightly grouped together; the sow coming to the rescue as a black wolf flees while looking back over its shoulder; the sow standing nose-to-nose with the black wolf, the cubs behind her and the black wolf backed up by two gray wolves — a Yellowstone standoff; the sow standing upright on its hind legs as it looks toward the photographer amid a gathering of crows, magpies, the cubs and one wolf.

The interaction played out over three days, Sept. 15-17, weeks before a government shutdown closed the park to the public. Bengeyfield had heard about the photo opportunity from his friend, Bob Landis, a renowned videographer who roams the national park.

Bengeyfield estimated the human crowd gathered to watch the animals numbered about 125. To see the best show, they had to arrive early. That’s because most of the action occurred at first light when the sow and cubs sauntered down to the kill site.

Unfortunately, at that time of day the light for shooting photographs was dim. Bengeyfield was using his 600mm lens topped with a 1.4 converter to get closer to the action, effectively boosting the lens to 1,260mm.

“But even then the image had to be cropped,” he said.

Feeding frenzy

Fall is when bears enter a phase called hyperphagia, when they are trying to consume as many calories as possible to build up fat before entering hibernation. That can make them extremely defensive of food sources.

Boars are also known to kill grizzly cubs so that the sows will go into estrus and can be bred by the boar. So to see four bears on one carcass prompted speculation that maybe the cubs were the boar’s offspring, Bengeyfield said.

Such communal feeding by grizzly bears on a carcass does occur occasionally, said Kerry Gunther, Yellowstone’s bear management biologist, although it’s not common. More often, a boar will displace a sow to claim the carcass. To ensure no other animal eats the carcass, the bear will often sleep on top of its dead prey.

The other theory is that, after feeding for a couple of days, the boar simply couldn’t eat anymore, so he wasn’t as possessive of the carcass when it came to the sow and cubs.

That wasn’t the case with the sow, her cubs and the wolves, though, Bengeyfield said. At times, the wolves would try and isolate one of the cubs, angering the sow who would charge out to protect her offspring.

“They never tolerated the wolves who tried to get the cubs,” he said.

Sticking with it

Bengeyfield is a retired Forest Service hydrologist who lives in Dillon. He often travels from his home to the park to shoot photos. He’s also given photo tours and taught classes in the park.

Often, his field trips are unproductive and he comes away with few good wildlife shots.

“There have been a lot of times there’s been nothing, so I was due,” Bengeyfield said.

So to have such an interesting interaction within camera range was exhilarating and fulfilling.

“When that occurs, you stay with it till it’s done,” Bengeyfield said. “That doesn’t happen that often that close to the road.”


Nature Notes Yellowstone as a mixing bowl

Yellowstone National Park seems like a giant mixing bowl, with park managers and scientists adding and changing ingredients, then stirring the bowl and studying the swirling brew to see how the changes affect the other parts of the mixture. This is especially evident in the park’s populations of aspens, willows, elk, wolves and grizzly bears.

In 1968, park managers stopped culling the elk herds in the northern part of Yellowstone. After that, elk numbers increased to a 1992 high of an estimated 20,000 elk. Grizzlies in the Greater Yellowstone Ecosystem suffered a population drop to perhaps as low as 185 bears in the 1970s. Following changes in bear management, their numbers have rebounded to over 600 bears at the present. Meanwhile, along with the rise in elk numbers, the number and size of willow and aspen stands has dropped precipitously.

The biggest change to the mixing bowl came with the re-introduction of wolves in 1995. Since then, elk numbers have dropped by 60 percent to 3,900 elk, apparently due to both wolf predation and the current drought. Wolf numbers built to a high in 2007, but have since dropped by 60 percent to 2012’s 98 wolves living in 10 packs, apparently due to fewer elk and disease. The packs in the park’s interior have dropped less than the packs along the northern edge, apparently because interior wolves rely more on bison and less on elk.

Amidst all of this swirling mixture, the clear winner in terms of population has been grizzly bears, who continue to increase in numbers. It helps that wolves are providing meat for bears and it is estimated that 80 percent of wolf kills are seized by bears.

In a video watched last fall in West Yellowstone, a grizzly bear casually followed a wolf pack, obviously waiting for the wolves to make a kill so that the bear could then take it away. Wolves may be more agile and able to harass a bear, but the powerful bear usually wins possession of an elk or bison carcass.

Bears do not often kill adult elk but they do kill three times as many elk calves each spring as wolves. It could be that increasing bear numbers are also helping suppress the elk population. It is not thought, however, that bear numbers are influencing wolf numbers.

A recent study pointed out that bear scat contains double the amount of berry remains as scat did a few years ago. The reason seems to be fewer elk are eating fewer berry bushes, therefore providing more berries to bears each fall, at a time when bears need to pack on the pounds in preparation for winter’s hibernation.

During the re-introduction of wolves into Yellowstone, there was talk of why this country had so few beavers. The huge elk population was eating the young aspen and willow shoots, and starving out any beavers. Wolves would create a “landscape of fear” forcing elk to move around more and reduce the pressure on aspen and willow stands.

Recent studies have found, however, that the aspen and willow stands are still not recovering. While wolves are eating elk, they are not forcing elk to change their browsing habits.

Now it is thought the park’s wildfire suppression strategies are also limiting new aspen and willow growth and further steps will need to be taken to increase aspen and willow stands.

The stirring of this beautiful bowl goes on and only time will tell what happens next in this swirling mixture of willow, aspen, elk, wolves and bears.


The Trophic Cascade from the Gray Wolf

The Canyon Wolf Pack alpha pair lead their pups along a ridge near Mammoth Hot Springs in Yellowstone National Park, Wyoming. (Mike Cavaroc)
The Canyon Wolf Pack alpha pair lead their pups along a ridge near Mammoth Hot Springs in Yellowstone National Park.

I won’t waste your time in discussing political agendas and biases for and against the gray wolf. We all know that it is a controversial species that many feel is not at all welcome in nature, despite the fact that it has been an integral part of that very nature for tens of thousands of years. Virtually all of the biases against these mystical creatures comes from a simple misunderstanding of their very nature. In previous posts, I have discussed at length why more wolves are needed across the country and dissected the bias from both standpoints. One key factor I have never laid out in full detail, however, is the trophic cascade of events that happens once wolves reestablish a healthy presence in their chosen environment.

First of all, what exactly is a trophic cascade? Put simply, a trophic cascade is a series of natural events that occur from a predator’s presence that benefits life farther down the food chain. In this case, just by doing what a gray wolf is naturally supposed to do, life all around it flourishes, as outlined below. These are not theories or hopeful expectations of what could or might happen, rather, these are actual processes and reactions that have happened and have been documented through both eye-witness accounts and collected data from the last two decades in the Greater Yellowstone Ecosystem.

An Elk’s Role in the Trophic Cascade of Wolves

Bull elk who kept their antlers through the winter run through sagebrush in Grand Teton National Park, Wyoming. (Mike Cavaroc)
Bull Elk Running

One of the two most controversial subjects when discussing the wolf (the other being cattle ranching), elk are the primary ingredient when it comes to the trophic cascade. As the gray wolf’s first choice of food, wolves routinely and systematically weed out the sickest and weakest elk. This has been proven over and over again thanks to the autopsies carried out by Yellowstone National Park on the elk that have been preyed upon by wolves there. This leaves only the stronger and more agile elk alive to pass their genes on, making the entire herd stronger.

How Trees Flourish with Wolves Present

With a consistent threat of being chased around by wolves, elk are on the move more and more with any sign of danger. Since aspen, willow, and cottonwood tree sprouts are a good source of nutrition for elk, the movement of the herd allows these sprouts to grow into mature trees. In the absence of wolves, the elk become complacent, often staying in one location throughout the summer season, never allowing the sprouts to grow enough to become full trees. As a result, all of the aforementioned trees begin to suffer because none of the younger trees are given enough time to grow. Only with a healthy presence of wolves do all these trees begin to thrive again.

 (Mike Cavaroc)
New aspen tree growth

The image on the right clearly represents the difference in the trees due to the presence, and in this case, lack of presence of the wolves. The old, tall tree in the foreground was leftover from when wolves were last roaming the area before their extirpation in the 1930s, or sooner. After that there was no new aspen tree growth because of an exploding elk population and a lack of predators to keep the elk moving, thus the elk were free to graze on all the new sprouts. The large, extensive grove of trees that are smaller are all less than 20 years old, whose growth coincides with the reintroduction of wolves to the region. The image illustrates just how many aspens were trying to grow, but never could until the wolves came back. Of the thousands of new trees that would not even fit into this photo, there were less than a dozen adult trees alive, and there are groves just like it all over Jackson Hole and beyond.

Why Beavers Owe Thanks to Wolves

A beaver chews on an aspen tree branch in its pond in Grand Teton National Park, Wyoming. (Mike Cavaroc)
Beaver Eating Aspen Branch

With aspen, willow, and cottonwood trees all beginning to grow into healthy adult trees, beavers will now have plenty of food to build dams and lodges, in addition to having a plentiful food supply. Prior to the wolves’ reintroduction in Yellowstone National Park in 1995, the beaver was on the verge of going extinct in the area. Even by 2001, only one full beaver colony existed. By 2011, there were nine beaver colonies spread out throughout the park, all because wolves chased elk, thus allowing trees to grow which allowed beavers to use for food and construction.

How Beaver Ponds Benefit the Ecosystem

A moose calf drinks from a pond in Grand Teton National Park, Wyoming. (Mike Cavaroc)
Moose Calf Drinking in Pond

With a healthy beaver population come more beaver ponds. With more beaver ponds come more places for migratory birds to stop and rest along their journeys. Likewise, the riparian environments invite many other bird species to nest while also providing a drinking source for countless animals. The beaver ponds also act against erosion and provide even more nourishment for vital willow trees, which the beavers themselves depend on, as well as moose. Though moose can become prey for wolves, moose also depend heavily on willow leaves and pond vegetation in the warmer months, in addition to having a cool place to lay down and keep out of the heat, all provided by beavers. Calmer portions of the creeks also provide a comfortable environment for otters, fish, and amphibians.

Why Grizzly Bears Partly Owe Their Recovery to Wolves

Grizzly Bear #610 of Grand Teton National Park shows one of her three cubs how to rip down an aspen tree. (Mike Cavaroc)
Grizzly Bear and Cub on Aspen

Wolves are the only predator that will routinely and regularly take down adult, big game wildlife larger than the average deer. With the carcasses that they leave behind, a plethora of other animals benefit. The grizzly bear was never fully extirpated from the lower 48 like the wolf was. A very solitary animal, a grizzly bear can survive deep in treacherous terrain, easily evading humans. As a result, a small presence managed to survive in the 20th century in the most remote areas of Yellowstone National Park. Their recovery into the latter half of the century was still remarkably slow and sightings were very rare. Enter the gray wolf. Within a matter of years, reports of grizzly bear sightings began to come from as far away as Grand Teton National Park to the south by the end of the century. Now, Grand Teton National Park boasts equal, and often times better, grizzly bear viewing than its northern neighbor, Yellowstone National Park. When wolves take down an elk, they gorge themselves with up to 20 pounds of meat each before retreating back to the den, often leaving a lone wolf to guard the carcass, unless the pack itself has had enough. That still leaves hundreds of pounds of nutrition for any other animal capable of chasing away a wolf, particularly a grizzly bear. With the extra nourishment during spring and summer months for grizzlies and their cubs, the grizzly bear population began to explode around the region, paralleling the wolf population while this other vital predator began to help balance out the ecosystem.

Coyotes Return to Scavenging with Wolves Present

A coyote quietly sneaks through snow and sagebrush in Yellowstone National Park, Wyoming. (Mike Cavaroc)
Coyote sneaking through snow

Coyotes are not predators. If you see a pack of coyotes hunting an animal, that is a sure sign that that ecosystem has a severe lack of predators. Coyotes by their very nature are scavengers and rodent hunters. In areas where wolves have been, or are, absent, coyotes are frequently seen harassing animals that they are simply not equipped to take down. Doing so is a clear indicator of how desperate they are for food. With wolves present, the carcasses that they leave behind are plenty of food for coyotes to eat from and maintain a healthy life until the next meal, even after grizzly and black bears have had their fill. Similarly, wolves kill any coyotes they find in their territory. This leads to a smaller coyote population, allowing for many other species to establish a more meaningful presence. Hares and even young big game, such as deer and pronghorn, are given more of a chance to grow into adults. Fewer coyotes also means more squirrels and ground rodents, leading to a much healthier population of birds of prey such as bald eagles and owls.

With Less Coyotes, Foxes Have More Presence

A red fox curls up for a nap on the snow in Grand Teton National Park, Wyoming. (Mike Cavaroc)
Fox sleeping in snow

Thanks to a smaller coyote population, foxes now have the opportunity to feed on more wildlife, such as hares and ground-nesting birds such as killdeer. With foxes preying on many of those animals, even the vegetation on the ground is also affected. Bugs that live on those plants are also affected because of the ground-nesting birds. As a result, this creates more balance in the ground vegetation itself.

With Wolves Nearby, Cougars Return to Their Natural Habitat

Mountain lion kittens sit cautiously behind their mother in Grand Teton National Park, Wyoming. (Mike Cavaroc)
Mountain Lion Mother and Kittens

Without the presence of wolves, mountain lions often venture into open valleys to find their prey, a place that is very outside of their normal habitat. Naturally, cougars prefer dense, wooded areas with plenty of trees. Without another significant predator to take down big game adults, the mountain lions often had no choice but to wander into valleys to find their prey. Upon the return of wolves, however, deer began to flee back into the trees. In addition, the wolves would take over the mountain lion carcasses lying in valleys. This led to a shift in both the mountain lions and their prey as both fled back into the woods. With wolves back in their territory, mountain lions can now return to being the dominant predator in the forests. (Bears are often found in forests, but prefer to hunt and graze in meadows.)

Other Locations Suffering from a Lack of a Trophic Cascade

The canyon walls of Zion Canyon begin to cast shadows across Zion Canyon in Zion National Park, Utah. (Mike Cavaroc)
Zion Canyon from Angel’s Landing

Anyone who has been to Zion National Park has most likely visited Zion Canyon and seen the lush cottonwood trees lining the Virgin River. Did you know, however, that those cottonwood trees may not be around forever? Heavy human traffic in Zion Canyon has forced the historically rich mountain lion population to flee the area, leaving the native deer population to explode and casually graze wherever they want on whatever they want. This is having a devastating effect on new cottonwood trees as well as the river channel itself. Similar catastrophes are occurring completely under the radar in Yosemite National Park and many other areas as well.

So how do you dissipate human traffic to a protected area? Protect more areas. Millions of people plan out vacations every year around protected areas such as national parks. If there were at least twice as many of them, more people would have more options to visit, and from there more solutions could be found to help reestablish a healthy ecosystem. It certainly would not fix the issue alone, but it would definitely be a good first step in the right direction, while at the same time bringing an enormous boost to the economy.

It is truly remarkable how one animal affects an entire ecosystem. Take that one animal out of the equation, and everything you have just read falls completely apart. Gray wolves, and in many areas cougars, are the cornerstone of a healthy ecosystem and anyone who will tell you otherwise has simply refused to educate themselves on how the natural world operates in perfect harmony when it is allowed to. More protection and more tolerance of our predatory treasures are not just good ideas, but undeniably required in order to preserve and maintain the natural beauty of North America.


Hard wolves’ lives as hunter: smashed skulls, missing teeth and broken ribs are common injuries

Experts study wolf skeletons for clues into behavior

Becky Kramer The Spokesman-Review

The wolf’s skull told a painful story. Teeth were broken and missing; the jawbone infected. An injury – probably caused by a kick to the wolf’s face – had also festered.

Despite poor health, the gray wolf kept his status as alpha male of the Rose Creek pack until he died, probably of septicemia, said Sue Ware, a paleopathologist who works for Denver’s Museum of Nature and Science. A week before his death, tourists in Yellowstone National Park videoed him “hanging off the rear quarters of an elk,” Ware said.

It’s a remarkable story, said Ware, who studies the bones of Yellowstone’s wolves after they die.

“Here’s an animal – the entire front part of his face is infected. How much pain was that?” she said. Yet the wolf still managed to clamp its teeth into a fleeing elk.

Ware is about halfway through a 10-year study looking at Yellowstone wolves’ health histories and cause of death.

Wildlife research often focuses on bigger picture issues, such as wolves’ impact on deer and elk populations, or landscape level changes since wolf reintroduction. Ware’s work, however, takes a more intimate look at the predators’ lives.

Her research will help shed light on how disease and injury affect individual behavior, and ultimately, the pack.

Ware’s work underscores the risks that wolves take in pursuit of prey. Smashed skulls, missing teeth and broken ribs from elk and bison hooves are common injuries.

One wolf skull had a healed-over bite wound from a cougar attack.

“To be an alpha wolf, you either have to be successful in avoiding disease or injury, or have the fortitude to suffer through,” said Jim Halfpenny, a carnivore ecologist from Gardiner, Mont., and a collaborator in Ware’s research.

“We find a lot of bite wounds in the muzzle from pack disciplinary action,” he said.

The research is part of the Yellowstone Wolf Recovery Program through the National Park Service.

Ware’s work is forensic in nature. Yellowstone technicians look for evidence at the scene about the wolves’ cause of death when they pick up the bodies. Observations of park biologists and regular Yellowstone wolf-watchers are often invaluable for reconstructing wolves’ activities in the days before their death.

“This is the only place in the world where you can do this kind of study,” Ware said.

The dead wolves are stored in a freezer at Mammoth Hot Springs in Yellowstone until Ware can collect them. She uses Colorado State University’s laboratory space to skin and dissect animals.

Each medical exam takes four days, including photographs and drawings. Cataloging the bones takes another two weeks. So far, she’s processed 217 wolves. Twelve more are in the freezer.

While the carcasses provide important information, skeletons are Ware’s forte. She also studies the bones of dire wolves – a larger, North American wolf that went extinct about 10,000 years ago. The skeletons tell her that wolf injuries have been consistent over the centuries.

“When you go out in the morning, you’re not sure if you are going to come back, or come back in one piece,” Ware said. “If you get kicked or stomped on or gored, infection is always lurking.”

Few wolves in Yellowstone live beyond age 10. Besides the injuries from hunting, wolf-on-wolf violence is another significant cause of mortality.

After Ware’s studies are finished, the wolf skeletons are returned to the Heritage & Research Center in Gardiner, which houses the National Park Service’s collections.

Ware, a supporter of wolves’ return to Yellowstone, said she hopes her work will give people a better appreciation for predators’ dangerous and difficult lives.

“Ninety percent of people on the planet don’t have any idea of the role that carnivores play” in the ecosystem, she said.