CHAPTER 8
To the extent we can ever paint a rich and meaningful portrait of a wolf’s life, we have to first understand that its very existence turns around markedly different behaviors at different times of year. Wolves at this latitude breed in February, giving birth in April after a gestation period of about sixty-three days. From that time on the animals will spend their summers anchored either to the birthing den or, beginning about a month later, to aboveground, denlike locations called rendezvous sites. The sole event that allows the group to finally transition out of this somewhat rooted period to the highly free-ranging behavior we see through winter is the physical maturation of the pups. As soon as youngsters are capable of traveling with the adults, typically in September or October, the pack begins to move as a unit.
While as researchers we invariably end up juggling a variety of investigations, what drives much of our work has to do with figuring out the exact nature of the relationship between wolves and their prey. Historically, across North America this has been one of the most controversial wildlife management issues ever considered, reflecting the fact that wolves have a lot of influence on prey animals that we humans tend to want for ourselves.1 During the early phase of this project, I polled wolf biologists across the continent, asking what they thought would be the most important study task we could undertake, both during and after the initial releases. A clear majority said we should monitor kill rates. In other words, most scientists felt it vital to determine how many prey—or more specifically, the amount of meat ingested per wolf—was occurring over a specific amount of time.
With this in mind, the first thing we did was set up a study to determine what kind of prey wolves were choosing, as well as how often they managed to actually make a kill. The idea was to answer that question posed by the scientists at two different times of year: first in early winter, when prey animals are healthy and usually difficult to bring down, and then again in late winter, when the prey is a lot weaker, and therefore far more vulnerable. Once again we turned to Isle Royale for ideas. Every year since 1958, from January through early March, researchers there have flown out to the island to carefully monitor wolf moose interactions. These flights, which occur every day the weather permits, have as one of their main goals to find wolf kills—a task made easier both because moose are large, so the wolves spend a lot of time on each kill, but also by virtue of the fact that midwinter thaws on the island are rare, which makes it much easier to snow track from the air.
But conditions are a lot different in Yellowstone, where mountains and forested ravines make it difficult to track animals from overhead. What’s more, winter thaws are much more common here, and along with gusty winds can make snow tracking difficult. Throw in several thousand ungulates, which in their own comings and goings often end up erasing many of the wolf tracks, and you can see that emulating an Isle Royale study—especially without radio collars—would be incredibly challenging, if not impossible. Still, we used the pearl of the Isle Royale idea, flying every day the weather permits, spending much of our time looking for kills.
Given that we couldn’t sustain the more than two months of flying currently being done at Isle Royale, our next task was to come up with a workable research schedule. To help with this part of the equation we turned to the Brooks Range of Alaska, where biologists Bruce Dale and Layne Adams had come up with the idea of monitoring wolf killing activity through thirty-day study periods, flying every day possible for a single month.2 Because we needed snow on the ground to aid us in spotting kills, we decided the early winter study should take place from November 15 through December 14, while our late winter period would go from March 1 through March 30. Just as on Isle Royale, we named these intensive research periods Winter Study, and they’ve become an enormously important part of our program. During the course of these periods we try to reach every wolf kill, except the extremely remote ones, traveling by foot, ski, or horseback, thereby gaining a lot of details not evident from the air.
A backbone of our work—here, as with wolf studies in other places—is fixed-wing aircraft, in particular that tried-and-true airplane of the far northern bush, the Piper Super Cub. Capable of carrying only a pilot and passenger, the Super Cub is for starters inexpensive to operate. To put it in perspective, flying a Super Cub costs us around $125 per hour, compared to anywhere from $700 to $1,400 per hour for a helicopter. First built in 1952, the model we use (PA-18) is unique among airplanes for the almost unmatchable lift provided by the wing. It’s highly maneuverable at slow speeds, can make tight circles, and has proven so safe at low elevations that some people know it as the poor-man’s helicopter. For all these reasons, probably more North American wildlife research is done from Super Cubs than from any other airplane. Some pilots are so enamored of the Super Cub that it’s the only plane they’ll fly, leading them to be known by the moniker “Cub Pilot.”
Given how astonishingly visible many of Yellowstone’s wolves are from the ground, we also monitor kills by stationing observers there. Actually, packs living close to the highway in the northern portion of the park have proven so easy to watch that observers can determine whether they have a kill on an almost daily basis. This information is ultimately compared with that gathered by the aerial crews. Using both sets of statistics we then apply a fairly complex mathematical equation to help adjust for human error, as well to more closely estimate the likely number of kills neither ground nor aerial crews were able to find.
If this all sounds like a lot of work, it is—far more than the government has money to pay for. For this reason each year we assemble an extraordinarily dedicated team of volunteers—nine people for each and every Winter Study. Without their assistance, we couldn’t pull off the project. Almost to a person these people dedicate their hearts and souls to the task, giving themselves over to hard work in bitterly cold conditions, the hours often spanning daybreak to dark. Prior to each Winter Study we provide a three-day training session, during which knowledge gets transferred from experienced volunteers to those newly hired. This mix of new and old helpers goes a long way in assuring the data are gathered with a high degree of accuracy. (It takes a person about one Winter Study to really get the hang of it; thankfully, most who come stay on for more than one season.) We’ve never once advertised for these positions. Word of mouth, mixed with the intense interest many people have in wolves, has proven more than enough.
What we’ve learned about wolf kill rates—that question so many biologists were curious about—is that on average Yellowstone’s wolves kill 1.4 elk per wolf per month in early winter, and 2.2 elk per wolf per month late in the season, for an average of 1.8 elk per month across the course of a winter. This means a group of ten wolves—the average pack size in Yellowstone—takes an elk about every third day in early winter and one about every other day in late winter. (Curiously, while from 1995 through 2000 the kill rate on the northern range showed exactly this kind of increase across the winter season, since 2000 such swells haven’t occurred. In other words, for some reason the wolves are eating less than they used to. Supporting this finding is the fact that the weights of the northern range wolves, especially pups, declined, while in the park interior weights held steady. We suspect this had something to do with the region’s prolonged drought.)
It’s worth noting that shortly after this book was first published in 2005, wolf kill rates during winter actually declined, dropping by about one elk per wolf per month. And yet actual consumption rates didn’t decline at all. In other words, even though the number of elk kills had gone down, the wolves were eating the same amount of meat. This is explained by the fact that in the early years wolves were taking more calf elk and old cows. Then, when the region was hit by drought, wolves began taking more bull elk instead, capitalizing on the fact that drought causes big reductions in the nutrition quality of vegetation, and that tends to weaken bull elk. This lasted three or four years, and then, with recent years bringing more moisture, and thus better grazing opportunities for elk, the wolves switched back again, relying on old cows and calves.
As for the summer months, our research suggests wolves eat roughly 25 to 35 percent less at that time of year. Some of this summer diet consists of mule deer, which return to the park after having wintered outside its boundaries.
Crunch the numbers and you end up with a grand total of about 180 to 190 elk being taken every year by each ten-member pack on the northern range. If we assume that interior wolf packs kill about the same number of elk that the northern range packs do—and we think they do—the number of elk killed every year across Yellowstone would be 3,000 to 3,200. Again, these are ballpark figures. Besides having learned a lot about how many prey animals wolves take, we’ve also gained a better understanding of how they go about it—knowledge earned from actually watching them interact with elk and bison. Once again, initially we didn’t think such insights would be available to us, given that elsewhere in North America wolf attacks on prey are rarely witnessed. In his thirty-five years on Isle Royale, for example, Rolf Peterson has seen only six kills.3 Compare that to the past decade in Yellowstone, where collectively we’ve seen more than a hundred. For starters, our observations confirmed what other studies elsewhere have suggested, which is that wolves manage to actually make a kill only about 15 to 20 percent of the time.
One of the questions we’ve been pondering as of late has to do with bison. At the time wolves were reintroduced to Yellowstone, there were roughly five hundred bison on the northern range in winter; today there are more than two thousand. Is it possible we could simply be swapping the enormous elk herd that was here in the mid-90s for a big bison herd? Bison, by the way, are estimated to consume as much vegetation as two or even three elk. What’s more, because they have a bigger gut, bison can process poorer quality forage than elk can, which means they avoid the whole business of following the “green wave” each spring, tracking through the summer that grass that holds the highest nutrient content. (For more about the green wave, see page 178.) Today, when elk make their autumn trek from the high country back down to winter range in the Lamar Valley, they’re finding several hundred bison have been camped there. Could there end up being a competition for food between elk and bison? Is the northern range going to become a wolf, elk, bison system, as has long been the case in the interior of the park? (Right now bison aren’t heavily preyed on by wolves; that said, bison still die, of course, and the carrion from those animals can be an important source of food for wolves.) Our next research project will hopefully begin to answer these important questions.
Most wolf researchers feel that as wolves travel they also hunt. How much energy they put into that hunting, though, depends on their level of motivation. If it’s not been all that long since a wolf fed, the desire to kill again will be fairly low; still, stumbling across a vulnerable prey animal may lead to a halfhearted attempt at making a kill. The hungrier the wolf gets, the more energy it will give—and the more risk it will take—for the chance to gain a meal.
In all probability wolves carry a kind of territorial map in their heads, knowing full well which places on their home ground are likely to provide the best hunting opportunities at various times of the year. What’s more, their noses are easily good enough to allow them to detect prey from several miles away. On first encountering a prey animal, wolves often just watch them (indeed, that may be all they do), looking for any sign of vulnerability. For their part, any elk within eyeshot will often go from a state of casual attention to a heightened state of alert only if they see a wolf showing signs of actual hunting. Sometimes that means wolves dropping into a low, half-crouching posture, but more often it has to do with more subtle clues, rules of the game that are difficult for most of us to even perceive. Either way, this tendency of prey animals to not react to wolves unless they’re really a threat is critical when it comes to conserving energy. In winter especially, any animal that bolted at the mere sight of a predator would have a hard time surviving.
If the encounter does escalate beyond a spectator sport, the wolves will approach the prey, interacting with it as a means of testing. (Indeed, it’s helpful to think of each state of a wolf-prey encounter as an ever more stringent test to determine vulnerability.) Still, even as things grow more intense, the encounter is as likely to simply end as it is to lead to an attempt at a kill. Often when wolves approach, prey will run from them, which can result in a chase—what we call an attack. Sometimes, though, the prey animal won’t flee (this is especially common with bison), preferring instead to stand its ground. By all indications, this is a great strategy for rebuffing a wolf attack. Making a kill is a lot harder for a wolf when a prey animal is facing it, with its strong kicking legs and sharp hooves—and in some cases, horns or antlers—poised and ready, than when its legs are otherwise occupied in running away. In November 2004 I watched three wolves attacking a herd of about two hundred elk. One cow elk not only refused to run but actually charged the wolves, at which point they merely jumped out of her way. As the chase unfolded, the fleeing herd cycled back around a few times toward this cantankerous cow, and every time the wolves chose to give her a wide berth. Clearly, they wanted nothing to do with her.
As the attack continues to escalate, the wolves may pick out either a group of fleeing prey or a lone individual. Again, what they’re doing comes down to a matter of testing, trying to target only catchable animals. Once a prey animal is targeted, the wolves may or may not attempt to actually capture it. In fact many attacks end right there, as the wolves realize the prey is healthy enough to outrun them. If it is vulnerable, though, the wolves may attempt to take it by trying to sink their teeth into the prey animal and then hang on. A wolf’s canines are especially well suited for such a task. The base of these teeth are elliptical—as opposed to round, like a cat’s teeth—which allows them to withstand extraordinary amounts of forward and backward force without breaking.4 While of course such an event is no picnic for the prey, it can be brutally hard on the wolves, too, since sinking their teeth into a running or kicking prey animal can result in broken ribs or legs, cracked skulls, even death. I’ve seen wolves that were hanging on a prey animal stepped on, kicked, flung into the air, and slammed into logs. Wolf 174, a former alpha female of Mollie’s Pack, badly injured her front foot while attacking a bison. I watched her limp for months. For a time she wouldn’t put any weight at all on the foot, yet at the moment the pack encountered an elk or bison they wanted to kill, she was right there, trying her best to help. I was amazed at her dogged tenacity, despite what looked to be a severe wound.
After painstakingly analyzing several hundred wolf attacks in Yellowstone, researcher Dan MacNulty found that wolves attempting to kill prey animals tend to display six behaviors, or “states.”5 These are search, approach, watch, attack, target, and capture. These states can vary in their order, be repeated, or even come to an end only to start up all over again, at least until the wolves finally see what they need in order to move in for a kill. And again, most of the time it’s the prey that wins.
As we’ve suggested, when it comes to wolves selecting prey, elk are clearly the animal of choice. Yet depending on the season, a wolf’s diet may broaden to include several of the other seven ungulates that live either full time or seasonally in Yellowstone. Wolves in the interior of the park especially may take bison, though for the most part this happens in late winter, when that thoroughly imposing creature is typically at its weakest. It takes a lot of winter to wear bison down enough so wolves can actually kill them, and even then the battles are fierce, often lasting the better part of a day. On at least one occasion a bull bison has killed a wolf and severely injured a second. Twice we’ve seen wolves thrown through the air like sacks of potatoes—once courtesy of a bison’s horns, the other by means of a hard kick from a hind leg. Yet by late winter Mollie’s wolves, for example, will be taking on average a bison every week. Again, the strategy wolves employ for tackling any large prey—be it bison or moose, bull elk or musk ox—is to avoid the front of the animal, where it’s all too easy to be kicked or gored by an antler or horn. The vast majority of attacks by Yellowstone wolf packs on bison are focused on the hind quarters.
There are also moose to be had in the national park, though over the past decade we know of only about three dozen actually falling to wolves. Moose too are formidable, with cows weighing in at about a thousand pounds, and bulls tipping the scales at roughly fourteen hundred—seven and ten times the size of a large wolf, respectively. Mule deer, meanwhile, as we mentioned, tend to migrate out of the park for the winter, though in summer they can be found in sufficient numbers for wolves to make at least an occasional meal. Mule deer make up just under 2 percent of a Yellowstone wolf’s winter diet, while in summer that climbs to 25 percent—a figure we determined by studying scats found around den sites. On the other hand there are relatively few white-tailed deer in Yellowstone; so far we’ve failed to record a single one being taken by wolves. Finally, we know of wolves taking only two bighorn sheep and two mountain goats, that low number reflecting the fact that both of these creatures can easily scamper across terrain completely unnavigable to most predators.6
No matter how many different prey animals might be available, wolves typically have a “primary choice” (which again, in the case of Yellowstone, is elk). What the wolves might do if the day comes when their first choice isn’t so readily available is one of the hottest questions in the park today. Some research suggests that as the primary prey base declines wolf numbers will decline right along with them—the prey numbers leading the predators. Other studies, though, indicate that wolves may switch to other prey, focusing instead on their second choice. Of course this assumes not only that there are sufficient numbers of that second choice but also, just as important, that the prey animals are actually vulnerable. In theory, at least, if wolves were able to successfully make such a shift, their numbers might stay higher. And that, in turn, could allow them to continue to exert a bigger effect on their primary prey, the elk. Elk numbers might stay lower, in other words, than if predator and prey populations were dancing to the same ebbs and flows.
As winter yields to the warming winds of April, we begin paying special attention to those wolves giving birth to pups—a phase of research called Den Study. Seeing a wolf den is a pretty hard thing to do, so well concealed are they, and for some packs we never do manage to find them. Still, it’s important that we try, especially given the need to manage the area surrounding the sites in a way that protects the wolves from human disturbance. The problem with such field work is that we run the risk of disturbing the wolves at a critical time in their life cycle. To reduce potential problems we never take up observation positions close to a den, using spotting scopes from locations often more than a mile away. (Such precautions aren’t always followed in other places. On Canada’s Arctic tundra, for example, where suitable den sites are limited and therefore predictable, some biologists conduct capture operations simply by waiting until wolves are denning.7 Outside the scientific community, at least one canoeing guide service in the region specializes in finding wolves at their dens, then picking up the pups and handing them off to clients.8 Research is ongoing to determine just how touchy wolves might be about such practices; so far, as with nearly everything else, the results are site specific and dependent on individual wolf personality.)9 We’re also interested in the phenomenon of wolves using the same den over and over, sometimes even after the death of the breeding female who excavated it in the first place, as we saw both with wolf Number 7 of the Leopold Pack and Number 42 of the Druids. From what we’ve figured so far, about 70 percent of dens are ones used in the previous year.
With the coming of summer we start the business of counting pups. If finding dens is tough, laying eyes on young pups can be harder still. We’re never quite sure if our counts are accurate—among other things, there can always be a pup or two hiding in the den while others are out frolicking—which means it’s difficult to make accurate estimates of early pup mortality. Those we do spot are often in full-blown puppy mode, biting the tails of adults, wrestling with each other in great tumbles of fur, leaping into the air for no apparent reason other than it’s a whole lot of fun. This penchant for play will continue well through the summer—from youngsters tossing pieces of carcass into the air and catching them like Frisbees, to entire families sliding down remnant patches of snow.
Well after the wolves have left their dens, we go in to gather data—making notes about the basic characteristics of a given site, also gathering scat, or feces, which allows us to figure out what the wolves are eating in the warm months. (Given the overlap in size of coyote and wolf scats, wolf dens are the most reliable places for picking up droppings.) For me this is the season of hiking and riding horseback to far-flung locations, drifting through the magnificent valleys, plateaus, and forests that comprise the Yellowstone backcountry; trailing along streams lined with monkeyflower and fireweed, watching for elk calves romping in the meadows, for the flash of red-tailed hawks.
Besides checking den sites and picking up scat, once a week we locate from the air all the packs in the park, tracking them by means of signals being given off by their radio collars. Among other things this allows us to examine differences in the use of summer territory versus winter territory, and through that, understand better how wolf life changes through the seasons. We know, for instance, that in summer wolves rarely travel together, instead moving singly or in twos or threes. This splitting up means locating collared wolves takes a lot longer in summer months than in winter, when the group tends to travel more as a single unit. Such loose organization reflects the kind of prey Yellowstone’s wolves tend to eat during warm months; generally speaking, in that season comes a more mixed diet—deer, elk calves, elk, carrion, ground squirrels, and beavers—whereas in winter months the packs dine mostly on elk.
No doubt about it, the wolf’s shining season comes in the heart of winter. Warm months bring heat, of which they’re not at all fond, as well as bugs and smaller amounts of food. And on top of all that, stronger prey. Besides, there’s really no such thing as weather too cold for a wolf. During initial reintroduction activity, with the animals in transport boxes and the thermometer stuck at minus thirty degrees, they seemed completely unfazed.
A wolf’s easy season, though, is for biologists the most challenging, in part because it’s when we do radio collaring operations—typically in January and February. (Lately, given that the drought of the past six years has rendered midwinter no better for snow conditions than earlier in the season, in 2003 we darted seventeen wolves in the month of November. Likewise in 2001 we darted several in early December.) Initially every wolf reintroduced to Yellowstone wore a radio collar. After all, the thinking went, we literally had them in hand, and by collaring each individual we’d be better positioned to gauge the success of the reintroduction. Since that time we’ve reduced the number of collared wolves to between 35 and 40 percent of the population. Roughly twenty-five animals are collared each year, 60 percent of them pups. Being able to follow the wolves on a regular basis allows us to better understand their needs and behaviors, and through that, hopefully make more intelligent management decisions. Collaring remains an ongoing priority both because batteries wear down after a time, but also because there are always animals dispersing, some going on to start other packs.
We now have in place guidelines that prevent us from collaring more than 50 percent of the wolves in any given pack. In addition ear tags, while used in many wildlife studies around the country, are intentionally not used on Yellowstone’s wolves. Both decisions reflect the fact that many visitors enjoy wild animals looking wild, with no evidence of humans having meddled in their lives. While we continue to place a high priority on gathering scientific information, so too do we need to be concerned about preserving the aesthetics of wild nature.
Make no mistake about it, catching a wolf isn’t an easy feat. Just keeping up-to-date with collar losses through death and dispersal can be demanding. Capture’s on my mind most of the year. On some days I look forward to it, but other times I dread it—not because of the work, but because of the stresses of wanting to do it safely, not to mention within budget. While flying around in a helicopter (used in conjunction with the Piper Super Cub) and then handling wolves offers great scientific opportunity, issues of logistics, weather, and general risk—not to mention the cunning nature of the wolves themselves—make for challenging days. Still, once aloft in the helicopter, strapped in with the door off and darting rifle in hand, scanning the wild landscape playing out below, I’m there 100 percent. Picking out a wolf to catch, hearing the sound of helicopter blades ripping and clawing at the air—in those moments absolutely nothing else calls for my attention. And these days, that’s a pretty remarkable place to be.
Once wolves have been chased by a helicopter during a darting operation, they become awfully clever at avoiding us the next time. Which is why it’s extremely hard to capture the same wolf twice. On top of that, helicopter darting was developed in the north, on lands without trees. But much of Yellowstone has plenty of timber, and at the point the wolves reach it, they win—a fact they’re clearly aware of. The Chief Joseph Pack especially shows uncanny skill at this kind of maneuvering; many a time I’ve hovered over them in a helicopter while they stood in the trees and looked up at me, seemingly defiant. On the other hand, we have as a goal to always chase the wolves as little as possible to achieve an acceptable degree of collaring. Not only do we want to avoid bothering wolves more than we have to—or, for that matter, provide them with a free education on how to avoid helicopters—but we also don’t want to ruin for visitors the blissful quietude of Yellowstone. (That said, the effort to protect the peace and quiet of the park isn’t without trade-offs. In 2005, for example, we reduced our summer overflight schedule by 40 percent. As previously mentioned, we had a record level of mortality in radio-collared adults. Less frequent overflights meant that by the time we got to the carcasses they were infested with maggots, preventing us from doing autopsies to determine cause of death.)
With other capture methods like trapping, the animal may lie alone, sometimes for hours, before someone reaches it. Darting allows us to tend to it right away. When a gunner hits a wolf with a dart, the helicopter immediately peels off, allowing the animal time to go down without any extra anxiety. Likewise, as collars are being placed around a wolf’s neck, vital signs are continuously monitored. Nor will we leave an area until we know the animal is up and about again—a policy that sometimes requires leaving spotters on the ground some distance away, watching for the animals to rouse. People often ask if this kind of handling might result in wolves becoming habituated to humans, in turn causing them to get into trouble in nearby communities or on cattle and sheep ranches. But as we mentioned earlier, wolves aren’t just naturally wary, but, lacking someone actually feeding them, are terrifically difficult to habituate. During darting operations, the only handling that occurs is when the wolf is sound asleep from the tranquilizer.
The systematic darting and collaring of wolves in Yellowstone began in 1998, nearly three years after the initial release. As a capture technique darting requires plenty of skill, the darter basically leaning out the open side door of a helicopter, secured by a harness attached to the frame of the aircraft. The movement of the machine tends to be erratic, subject to unpredictable jolts from ground winds, not to mention the swoop and wiggle that comes from the pilot trying to match the running of the wolves themselves. This is why, despite the best abilities of the man behind the dart gun, it’s all for naught without an incredibly skilled pilot at the controls, able to follow a speeding, zigzagging animal determined to find cover. Even under ideal circumstances it takes a gunner roughly five or ten seconds to reload, allowing a wolf running at thirty miles an hour to cover more than seven hundred feet.
Wisely, the Park Service insists on lots of training to be certified as a dart gunner. I completed such prep in 1999 in a course involving live helicopter trials, taught by National Park Service wildlife capture specialist Michael Coffey. Shortly afterward I traveled to Alaska to work with Layne Adams, a veteran wolf darter of the US Biological Survey. Well aware of the hazards that can come from getting overly excited, Layne treats the subject very matter-of-factly. Even so, the first wolf I ever tried to dart got away, basically because I forgot to pull the hammer back on the dart rifle. When I squeezed the trigger, nothing happened. The animal simply ran off into the trees. (The helicopter pilot nicknamed that wolf “Waterloo,” then insisted on finding him for me another day.) It would be the first in a long string of lessons about the need to be able to think clearly in the wake of what’s always a powerful rush of adrenaline—not to mention the occasional helicopter pilot yelling to “shoot now!” or offering not-so-helpful comments like “What happened? How’d you miss that shot?” I also learned a lot from US Fish and Wildlife Service biologist Carter Niemeyer, who by the time I got my feet wet had already darted several hundred wolves in the Lower 48. For a couple years we worked alongside each other, taking turns at the gun, routinely bantering back and forth about who was doing a better job and taking more difficult shots, a kind of friendly jabbing that allowed me to keep the pressure in check. Ed Bangs, wolf recovery coordinator for the northern Rockies, also was extremely helpful in the darting department.
Before actually climbing aboard the helicopter and putting my finger on the trigger of a darting rifle, I spent literally hundreds of hours flying in the spotter plane. Cruising some fifteen hundred feet above the ground, spotters—as mentioned earlier—are the eyes of the project, the ones who actually find the wolves for the darter. Spotters also keep a darted wolf in sight, so that when the drug finally takes effect, the helicopter can easily find the animal, pick it up, and take it to the people responsible for processing. While all this is going on the plane also stays in touch with headquarters, calling in every fifteen minutes, allowing us among other things to keep abreast of developing weather.
More often than not, the pilot of that yellow Piper Super Cub in the skies above Yellowstone is Roger Stradley—not just a superb pilot, but so well attuned to every aspect of the operation that we long ago started referring to him as “General Stradley” or just plain “the General.” Taught by his father, a World War II flight instructor, Roger’s been flying Yellowstone since 1952 and knows so well every creek, lake, mountain, ridge, and plateau that long ago I stopped even bringing a map. At this point he’s got roughly fifty thousand hours in this type of plane, and the way he flies gives life to the old saying that you don’t really fly a Super Cub, you strap it on. When weather moves in on us, especially wind, Roger has a handle on where he can go to get us out of it; some mountain passes or valleys work better than others, depending on the conditions, and he knows them all.
Sixteen years of wolf research in Yellowstone have brought plenty of excitement, especially during collaring operations. I recall in particular November of 2003—a time of year in the northern climates I’d grown to love, when the occasional brilliant sunny day slips in between the gray and wind and cold. It was to be our earliest starting date for collaring operations, the previous record having been December 10. On our list of most wanted for the day was the Geode Creek Pack, which by that point was down to just one collar for the entire group. Other targets we were hoping for included members of the Mollie and Nez Perce Packs—the latter wolves being especially challenging, given that they rarely presented themselves in places where they could easily be darted. Giving us hope on that first day was the fact that Roger Stradley, piloting the spotter plane, had found both packs out in the open—Nez Perce working the sprawling expanses of the Hayden Valley, and Mollie’s in that part of the Pelican Valley not heavily forested.
At the controls of the darting helicopter was an outstanding pilot, Gary Brennan of Hawkins and Powers Aviation, working a Jet Long Ranger III—an aircraft with a lot more oomph than some other models, which I never appreciated more than when we were dangling a paltry hundred feet or so above the ground. We left the airport at Gardiner headed first for Pelican—eager to reach Mollie’s wolves since only the two alphas of that pack were collared, and the batteries were getting old. Just as we were getting ready to leave, though, the General radioed from the spotter plane and changed plans, diverting us to the Hayden Valley to get the Nez Perce Pack instead. The call was confusing, what with to my mind Mollie’s being the bigger priority. But radio transmissions are never a good place for lengthy discussions, not only because words routinely end up cut or garbled, but because there’s a need to not tie up the air waves. I’d learn later that fog had rolled into the Pelican Valley, making work there impossible; Roger’s plan was to complete the collaring of Nez Perce first, at which point he hoped the weather in Pelican would improve.
This was my first darting trip of the year, so I was feeling a little rusty, full of early season jitters. While the Nez Perce wolves remained out in the open, I knew I’d have only one chance before they hit the trees, sending us back home to try again another day. Complicating matters was that there was only about an eight-inch layer of snow—not enough to slow the wolves down, leaving them fast-moving targets filled with plenty of “juke and jive.” Greyhounds, we sometimes call them in these conditions, speeding dogs that make landing a tranquilizer dart a tough proposition. Thanks, though, to some skillful piloting we quickly darted four members of the pack, including the old, grizzled-looking alpha female, Number 48, whose radio collar batteries were already dead. Also darted that day was Number 340, a two-to three-year-old female who later that winter would take off to form her own pack near Old Faithful, a group now known as the Biscuit Basin Pack. Yet when it came time to try for alpha male Number 72, whose collar also needed replacing, I missed badly.
By this time the fog had lifted in Pelican Valley, and we headed over to try our luck with Mollie’s Pack. We knew this would be a different operation altogether; both alphas were old, all too familiar with the darting drill, which meant they’d waste little time hustling for cover. Sure enough, even before we entered the outer edges of the Pelican Valley, they were up and running for the trees, all but two ignoring the hovering helicopter. One of those who paused for a second look was an enormous male, Number 194, last captured four years earlier, now wearing a collar with dead batteries. His sheer size reduced his capacity for fancy maneuvering, which allowed us to get a dart into him fairly quickly. The second animal was an uncollared pup, a lot more agile than big old Number 194, but whose inexperience led him to make the mistake of running into the open where we were able to quickly dart him. We called the General in the spotter plane and he told us that was it—there were no more wolves in the open. All things considered, not a bad start to the darting season.
The next day was a Saturday, but when it comes to these sorts of operations we have to work whenever weather is good and there’s aircraft available. What we needed was one of those rare November gifts I’m so fond of—a clear day with low winds—which is just what we got. As usual, the General was out early, locating the Geode Pack in a perfect spot. We needed Geode. They were a key pack, living in the middle of wolves and grizzlies, with cougars, coyotes, elk, bison, and deer. Tracking them, in other words, would allow us to learn not just about their movements but also about how they were interacting with these other species. As of that morning we had only one member of the pack collared, alpha female Number 106, whom we’d caught the previous year. (Number 106, as you may recall, had been a low-ranking member of the Druid Pack during that fateful brawl between Number 42, the so-called Cinderella wolf, and her superaggressive sister, Number 40. Following 40’s death, 106 would come into her own, proving herself an exceptionally skilled hunter.) The General knew how much we needed collars on this group, and there was an edge of excitement in his voice that left the rest of us amped up and ready to go.
When we arrived Roger had us set the copter down and wait. Since his earlier radio transmission the wolves had moved into a herd of elk—were chasing them, trying to make a kill. He was having trouble sorting things out, didn’t know how to direct us, what with wolves and elk running every which way. When we finally headed in, we discovered the wolves hadn’t actually made a kill, that the elk had run off; this was a bit of a relief, given that we try to avoid ever running elk with the helicopter. With the General cruising high above in the Super Cub, barking out landmarks to guide us in, we quickly spotted six members of the pack against the snow. Gary picked out a big gray, got me in for a good shot, and we had our first wolf. In quick succession he maneuvered in on another gray, and once again we hit pay dirt. Off in the distance we saw a black wolf running away and we decided to go after it.
I knew this wolf, Number 353, the only black member of the group—a small female that had been with the pack for about a year. Females, by the way, tend to be fast runners, much faster than males, not only because they’re somewhat smaller and therefore more agile—traits that make them great hunters—but also because they tend not to hesitate. Males by contrast seem more tuned in to defending territory, rather like a male lion who only looks after ground and leaves the hunting to the females. During darting operations there are times when males will actually turn and look at the oncoming helicopter, ready to take it on if need be, or at least think about taking it on, which tends to give us the split-second advantage we need to dart them.
This little black female had turned on the jets, wasting no time running for broken, rocky country across a mere couple inches of snow. Despite the low probability of capture, we flew along with her, just in case she made a mistake. Which is just what happened. Despite having beat us to the punch at the last minute, she dove underneath a boulder the size of a small house. At first I thought that was it, we were finished, but then I heard Gary say, “We got her,” and next thing I knew he was scouting out a place to land. “She’s in a hole,” he explained. “Go in and see if you can dart her from the ground.” A minute later I hopped out of the helicopter, while Gary took off again to transport the two wolves we’d already darted back to the handling crew, to begin processing and collaring.
When I walked up to the rock and looked down into that hole, all I could see were the wolf’s eyes, blinking at me out of the blackness. There was a light snow falling. To avoid unnecessary injury it’s important not to dart an animal from too close, so I had to back up some fifty feet up a slight hill. All the while those blinking eyes were on me, staring intently, though she made no attempt to run for it. I was back as far as I could be to still keep her in my sights, but even at that distance I wanted to make doubly sure my shot placement was perfect, hitting her in a fleshy part of her hindquarter. Yet all I had to go on was the shine of her eyes. I pulled the dart rifle up to my shoulder and aimed to the right about the distance I thought her rear would be from her face. She lay there with her eyes fixed on me while I held the rifle with my finger on the trigger, the two of us locked for several moments in a mutual gaze. I squeezed the trigger and “FSSSSST”—out came the dart. She did nothing. There was no acknowledgment that I’d hit her. I couldn’t shoot another dart, not wanting to chance giving her a double dose of tranquilizer, though I also wasn’t keen on crawling into the hole to confirm that the first shot had hit the mark. My only option seemed to be to sit in that lightly falling snow, waiting a little while longer before reaching down the hole to grab her foot, which would tell me if she was really out. In the end, though, it proved easier than all that. As I sat and watched, I noticed the shine of her eyes slowly disappear, the steady gaze and blinking finally fading to black, signaling that she was indeed asleep.
Even so, when the helicopter landed with project biologist Dan Stahler, I wanted to have a backup plan, on the off chance she wasn’t drugged after all. I told Dan I was going to load another dart, then stand with the rifle pointed in the direction I figured she would run. Dan, on the other hand, would be the lucky guy to crawl into the hole to fetch her. To be on the safe side he lightly poked her with a long stick, looking for a response. Nothing. Next he crawled down and grabbed her leg lightly, again waiting for a response, getting none. Once we were both comfortable that she was indeed sedated, he went in and grabbed her, carefully passing her out to me. Number 353 was safe in hand.
Capturing this little female was a lucky break. Her behavior was unique among wolves, and that fact meant new opportunities for us to learn. For one thing, she had a habit of splitting off from the pack for long periods, up to a month at a time, traveling alone. Every time we thought she was going to leave for good, dispersing from the group, she always came back. In April of 2004 she had a litter of pups at the same time as the alpha female, Number 106. While the birth of that litter eased her wandering ways somewhat—wolves almost never abandon their pups—still she managed to eke out a fair amount of alone time.
An important facet of wolf behavior to keep in mind during darting is that if we manage to catch the alpha female first, the alpha male will hang around. The opposite, though, isn’t true. Catch the alpha male first and the alpha female will make tracks, not waiting to see what happens next. I was reminded of this in February of 2004, when moving in to catch wolves of the Cougar Creek Pack near West Yellowstone, Montana. We flew in low, crossing over lands burned in the 1988 fires, the timber regenerating as “dog hair” lodgepole pine—so named because it grows thick, like the hair on a dog’s back. We could see the wolves running through the ten-to fifteen-foot-high trees, but branches in the way left us unable to get a shot. At the same time we had to deal with “sucker poles,” which are remnant trees from the burn sticking well above the sea of young timber, preventing us from getting low enough in the helicopter for a good shot. Pilot Gary Brennan has a special hatred for sucker poles, and was constantly on the lookout for them—a great priority, since a single strike would bring us down.
As the pursuit unfolded we spotted all but two of the pack of ten wolves spilling into a gully, headed for what we call Dry Fork of Cougar Creek. The two that split off, meanwhile, consisted of a small lead wolf being trailed by a much larger one, undoubtedly a male. No matter what we did, the male simply wouldn’t leave her side. Given that February is wolf breeding season in Yellowstone, we quickly surmised that this had to be the alpha pair, so we peeled off from the main group and went in for a closer look. Sure enough, they were both collared. The alpha female, Wolf 151, had first been collared in 1999 while a pup in the Leopold Pack; given that the batteries in these collars last anywhere from three to five years, hers were almost certain to fail any day. Getting our hands on her and replacing that collar would mean that in all likelihood we’d be able to gather data for her entire life, birth to death—an incredibly rare opportunity for any scientific study. I wasted no time letting Gary know through the voice-activated microphone that this smaller wolf was the one I wanted, and wanted badly. “That’s our girl!” I shouted. True to form, at that second Gary—always up for a challenge—came into his own, calling from a virtual treasure of helicopter experience dating all the way back to the Gulf War. His attention firmly fixed on the female now lunging through deep snow, Gary threaded a safe route for me to stick a dart neatly into her butt, in a single shot.
In all honesty, as thrilling as such moments are, I tend to enjoy the aftermath of captured wolves more than the darting itself. Though I actually studied and watched wolves for twenty years before I ever darted one, seeing this side of the animal has been completely new and highly revealing. Their beauty alone, which reveals itself well at such close quarters, is to me nothing short of remarkable. Through handling, a scientist has a chance to become intimately familiar with what he’s studying, able to learn in a much more intuitive fashion. There are other advantages too, in that we can gather biological samples, including blood, allowing us to assess not only the condition of the wolf, including its exposure to diseases, but also track its genetic history through DNA. At every such opportunity we also age, weigh, and take physical measurements.
Once darted a wolf typically succumbs to the drug within five minutes. In addition to being the gunner it’s my job to gather the sedated animals for the handling crew, which can be physically demanding. Carrying a 120- or 130-pound wolf through two and a half feet of snow, traipsing through tangled woods and steep gullies to a waiting helicopter, is more than enough to wear a body out. In January of 2004, for example, we were flying near McBride Lake and darting a 125-pound male wolf from the Slough Creek Pack. Unfortunately he went down in deep woods on a steep grade of some sixty degrees, where no helicopter could possibly land. The pilot, fully aware that this wouldn’t be an easy job, dropped me off and headed out to pick up the handling crew.
In the forefront of my mind, on that day and many others, was the fact that I’ve had back trouble since junior high school. For several weeks during the previous year I’d been barely able to stand up straight or even sit in a chair, having thrown my back out merely by picking up my eighty-five-pound dog after cancer surgery to load her into the back of our car. Indeed, in 2003 the pain was so bad that I’d had to dart with a brace. And though by the time we got to McBride Lake on that January day in 2004 such pain was long gone, the memory of it lingered, needling me as I headed down the hill to pick up what was by any standard an enormous wolf.
When I arrived on the scene, it was even worse than I feared. First I attempted the tried-and-true method of hefting him over my shoulders, but that proved impossible; I simply couldn’t get him over my head, and each try ended with me on the ground. Next I tried carrying him in my arms but kept slipping backward on the snow-covered slope. I was starting to think there was no way I’d ever get this wolf out by myself, so I began entertaining the idea of calling on the radio for help. Mustering the energy for one more good try, I began crawling up the hill on a contour, holding the wolf by the scruff of the neck and dragging him behind me. Every grunt-filled pull resulted in only a few feet of progress, and it didn’t take long before I was winded. Several times I almost lost the poor creature down the steep, snow-covered slope but I held on, terrified by the prospect of having to start over.
After about twenty minutes of this Herculean struggle, the helicopter landed again to pick me up. The pilot can’t help at all in such situations, being required to stay at all times with the aircraft, which essentially meant that I now had an audience. The pilot signaled me to take my time, so I toiled on, logging at least another ten minutes dragging the wolf in tiny increments, foot by foot, toward the waiting helicopter. By the time I made it I was more than dog tired. The bad news was that this was among the first wolves of the day; there would be others, and I’d have to pull it together in order to be capable of darting more. In fact no sooner had we unloaded the first wolf when Roger Stradley’s voice crackled urgently over the radio from the spotter plane, saying, “Let’s go, let’s go, let’s go,” which of course meant he had other wolves in his sights. A deep breath or two for me, then it was back to the chopper to strap myself in. As pilot Gary Brennan likes to say, when all the stars line up you gotta work, and the stars were definitely lined up: good weather, wolves in the open. And work we did, right up to the edge of dark, catching seven more animals before finally calling it a day.
One last contender for the most memorable day of darting occurred on January 17, 2005—and not just because it was only the second time we’d managed to capture ten wolves before the sun went down. At one point we were pushing hard to catch up with an enormous member of the Agate Creek Pack, male 295 (son of wolf 113, pictured on page 1 of the photo insert). Having been collared before, he was familiar with the drill. And while the last time he saw darters coming toward him he hustled away, this time he was determined to try a different tactic. Suddenly, with the helicopter almost upon him, he turned, considered the situation for a couple of seconds, then bared his teeth and took several steps right toward us. Snow was flying all around, churned by the wash of the helicopter blades. But there he was, fierce in the midst of the uproar, so close the pilot actually had to peel back. For a second I wasn’t sure if I’d have to kick him away. (One of the first rules of darting, by the way, is to never shoot an animal turned toward the gun, since it could result in a dart hitting him in the face or penetrating the rib cage.) All in all the encounter left me breathless, inspired by what was a supreme act of defiance.
Radio tracking animals has become a clear staple of professional wildlife biology. Each animal is assigned a unique radio frequency, thereby enabling us to study not just group dynamics but also individual behavior. For example, when we want to find the alpha male of the Druid Peak Pack, we tune the receiver to his specific frequency, listening for the beeps coming from the transmitter around his neck. This region actually played a key role in the development and first use of radio collars; noted biologists Frank and John Craighead, who studied grizzly bears in Yellowstone extensively during the 1960s, were among the first to use them in the wild.10 Meanwhile in Minnesota, Dave Mech was heavily involved with the design and testing of collars that would ultimately be used on wolves.11
Until recently, while collars grew smaller and more reliable, as well as easier to attach and more durable, there’d been relatively little change to the technology. Radio tracking always required biologists to be out in the field, close to his or her subject. Today, however, there are some new bells and whistles on the block, including GPS or “global positioning system” collars that actually communicate with satellites, precisely identifying on a grid system where a wolf is located at any given time. In the early versions of GPS this information was stored in the collar itself, awaiting retrieval; today, though, the collar can broadcast data to distant locations, in some cases right down to a biologist’s email box. This technology has made it possible for biologists to program collars to locate wolves at virtually any hour of the day or night, which means if something happens in the dark, like a wolf taking down an elk calf, we’ll know about it. Our current GPS collars can give us up to forty-eight location fixes in a twenty-four-hour period. (When you purchase a GPS collar, it comes with a certain number of “fixes,” sort of like minutes on a cell phone package. So if we purchase a collar with forty thousand fixes, those can be spent any way we like—at the rate of forty-eight times a day, or much more slowly, or some of both.
A good example of how this technology can be applied involves summer predation rates—in other words, what and how often wolves eat in the warm months. As mentioned earlier, during this season wolves are harder to spot—both because they’ve broken up into smaller hunting groups and because those groups are focused on smaller prey, which in turn makes kill sites harder to detect. Such problems can be solved at least in part with GPS collars, since they allow locations to be determined without anyone actually being there. During the summer of 2004, we fitted two wolves in two different packs with GPS collars—a yearling male from the Geode Creek Pack and a yearling female from Druid Peak—each device programmed to locate the wolves forty times each day. While we actually placed the collar in January, we were able to program it to not begin establishing those locations until May and June, thereby saving battery power in the intervening months. When the summer study period was over, we could send a signal to the collar, causing it to detach from the wolf. Once detached we were then able to track the signal and retrieve the collar, at which point we could download any remaining data. (Or at least that was the way it was supposed to go. Unfortunately on this one, unbeknownst to us, we ended up providing the manufacturer with some much-needed field testing.)
Our basic plan was to download locations every week and then hike to “clusters” of established points on the ground to see what was there—why the wolf may have been spending time in that particular location. But we didn’t yet know how to calibrate our searches. In other words, would two hours at one spot constitute a kill, or would that event typically require more than two hours? As time went on it became obvious that we’d have to examine many different clusters before we could get a decent feel for how long a wolf spent at any given site, understanding that taking an elk calf requires a lot less time than does a bull elk.
Unfortunately, the yearling female from the Druid Peak Pack we’d chosen for the study ended up being bred that year. This meant our predation study was a bust for this wolf, since rearing pups meant she’d be forgoing hunting activity, instead staying close to the den for a good six weeks after giving birth. This reduced our project to a single male, a two-year-old in the Geode Creek Pack. Happily, his pack’s territory was more accessible to us than that of Druid Peak, which made hiking to all these “clusters” a much more reasonable proposition. More importantly, the Geode Creek Pack wasn’t all that large. A big pack would mean many small hunting groups, and to get an accurate picture of what the pack was doing all units would have to be tracked. But Geode Creek’s smaller size, just six animals, meant the pack would splinter into fewer hunting groups, which in turn meant that the one individual we’d collared would better represent what the entire pack was doing. Indeed, most of the time there was probably only one hunting unit, given that two of the members were breeding females who wouldn’t be hunting much in early summer. That left only four to account for, and on a few occasions we observed them all hunting together.
Through May and June the collar worked like a charm. Dan Stahler, the project biologist leading the study, downloaded from it every week, plotted clusters on the computer, then hiked to each place where the wolf had spent more than two hours. This was an amazing effort, and Matt Metz, Janice Stroud, and Katie Yale worked almost nonstop to help pull if off, while Emily Almberg helped out when she wasn’t monitoring both wolves and people in Lamar Valley. (Since 2005, Matt Metz has taken over a great deal of the research involving GPS collars.) What we learned is that wolves do in fact eat less in summer, just as many researchers had hypothesized. The frequency of their kills dropped by about 25 percent compared to winter. Furthermore, and contrary to what many had supposed, wolf predation did not switch exclusively to elk calves, but rather calves were taken only as the opportunity presented itself. This alone was a valuable finding, given that some people had been suggesting wolves were all but wiping out elk calves soon after they were born.
By 2011 our use of GPS technology had grown considerably. During the months of May, June, and July, we now program the GPS collars to give us maximum input, which is forty-eight “fixes” a day. If two or more of these fixes are located in the same place, meaning there’s more than one wolf there, we start hiking. By the end of a given summer the crew will have walked nearly a thousand miles—a perfect combination, if you will, of a powerful new technology combined with old-school “getting out to see it with your own eyes.” In time GPS will no doubt allow us to ask more far-reaching questions. For instance, by placing high-frequency GPS collars on other carnivores, such as black bears, grizzly bears, or cougars, and then programming each collar to send data on the same schedule, we might learn a lot about how different species interact with one another. GPS might also allow us to trim our overflight operations a bit—a good thing both for the budget, as well as for general peace and quiet in the park.
There are some drawbacks to GPS. For one thing, while a conventional collar costs roughly $300, a GPS collar is about ten times that amount. What’s more, GPS technology draws far more heavily on battery power, making the collars last less than conventional models, though their performance continues to improve. As wonderful as such technology is, it will never replace being out there on the ground. Without visual connections it’s impossible to know many of the most basic things necessary to wolf research: how many other wolves a particular individual is with, or whether it might be interacting with an elk, coyote, or grizzly bear. Nor is there any hint of the kind of prey animal that’s been taken—be it cow, bull, or calf elk, or even bison or deer.
Finally, when it comes to science, it’s important to say a little more about climate change, a topic that’s received more and more attention here in Yellowstone since wolves were first reintroduced in 1995 and 1996. That a shifting climate is having effects on the national park there can be no doubt, providing challenging circumstances for trees, grasses, birds of prey, grizzly bears, wolves, and ungulates like moose and elk, as well as a whole host of other species. Prolonged drought and increased temperatures have both warmed and diminished trout spawning streams, for example, adding yet another stress to a fish already struggling against the predation of the nonnative lake trout in Yellowstone Lake. Up on the northern range, meanwhile, ponds and wetlands are drying out, resulting in drastic reductions—and probably the eventual demise—of at least three out of four amphibian species that have long made homes there.
The study of ecology can be said to have spun out of a growing understanding that when we tweak one strand in the web of life, the rest will quiver. What makes climate change so difficult to accurately anticipate is that it tweaks a lot of strands in the web at once; each of those strands will in turn have its own particular set of responses and subsequent effects. Still, climate research in Yellowstone is growing increasingly sophisticated, allowing us—even if only tentatively—to more clearly imagine the possible effects of climate change on wolves and their primary prey.
Let’s consider this topic from the perspective of the one animal most important to the survival of wolves in Yellowstone, the Rocky Mountain elk. For a great many centuries, every spring the elk of this region have engaged in a careful vertical migration, following the snow line as it recedes up the mountains, finding along that rising line the very best, most nutritious grazing opportunities. Researchers have recently started referring to this upward unfolding of plant life as “the green wave.” Along with reproduction, this is arguably the most significant cycle of the year, a critical opportunity for elk to get the nutrition they need to restore their strength after the challenges of winter. Historically, this greening occurred at lower elevations in March, then proceeded slowly upward, finally burning out in the high-elevation meadows sometime in early August. Today, however, the fuse of this process is both burning faster as well as being extinguished earlier in the year. (The opposite of the green wave is known as the “brownout,” which comes when heat and precipitation levels are such that the plant stops producing biomass. If the green wave is moving faster, it’s also true that brownout is coming earlier.)
As you might imagine, there’s no surer way to cause change in an ecosystem than to alter the basic food source of that system, which in Yellowstone consists of grass, as well as the leaves and stems of woody plants like willow and aspen. Consider for a minute the fact that each autumn, bull elk go through incredible physical struggles to assemble harems for breeding, all while taking in few or no calories. In years when the green wave tends to be on track, bulls are able to make it through those difficult times just fine. In low snow years, on the other hand, which are becoming more and more common, the bulls often go into rut without sufficient strength, in large part because of the green-up (green wave) having gone faster and ended sooner.
Meanwhile, the wolves have been paying attention. Over the past few years they’ve discovered that in the wake of light-snow winters (and therefore, a compromised green wave), bull elk can end up so exhausted after the rut that they can be successfully hunted, which isn’t an option when high-quality food has been plentiful well into August. At the same time, this fact of the green wave “fuse” burning faster may also prove to have effects on cow elk, who depend greatly on high-nutrition forage in late summer—both to build fat for the winter as well as to be healthy enough in the spring to produce milk for their calves.
And that’s just the tip of the (melting) iceberg. There’s also the whole phenomenon of elk migration to consider. Migration developed in the first place because it gave animals a longer shot at that green wave, allowing them, by moving to high-elevation meadows, to feed on high-nutrition forage until August. What might happen if the green wave is compromised—in other words, if the rewards of migration begin to shrink? Perhaps we’re already seeing clues from the elk around Cody, Wyoming. Research by the University of Wyoming suggests these animals are now staying at low elevations throughout the year, hanging out in cultivated alfalfa fields. And by all appearances, they seem to be doing better than elk still making traditional migrations. If we get to the point where spring treks into the high country no longer offer significant nutritional rewards, then why make them? Why take on a long, difficult journey, much of it with grizzlies and wolves staring your calves in the face, if you don’t have to? Is it possible that a movement going on for literally thousands of years is beginning to ebb? If so, what might it mean for hunters? Given that elk are taken in the fall, when they’re moving from high ground back to winter range, might there one day be significantly fewer animals available?
As ecologist Frank Egler noted more than thirty-five years ago, ecosystems aren’t only more complex than we think. They’re more complex than we’re even able to think.
All this talk of research brings to mind what’s become a common dispute in some circles about the practice of science, versus that of natural history. From a historical perspective, of course, all early science began with natural history. It was widely understood that before any scientific questions could be asked it was necessary to have a thorough understanding of the habits and characteristics of your subject. But in recent years some have been critical of such approaches, concerned that the observation part of the equation could well overshadow critical thinking. Seen through the lens of that concern, a man like Adolph Murie might be seen as “merely” a natural historian, since much of what he did was to go far afield in Mt. McKinley National Park and watch wolves.
But Ade, as he was affectionately known, spent countless hours so engaged, in the process witnessing not just wildlife but wild relationships of all kinds. His widow, Louise Murie McLeod, describes his labor-intensive approach to wildlife watching as “the Adolph Murie way.” (She sometimes went on to describe his dedication with a measure of exasperation. “He turned down trips to Africa so he could go back to Alaska. One would have thought twenty-five summers was enough.”) Murie’s style—patient, slow, noting his observations in a journal instead of on a spreadsheet—is today largely out of vogue. Most modern researchers specialize on tightly focused topics, always on the lookout for short-term results—an approach driven in large part by the institutions that provide grant money for the work, as well as the all-important opportunities for publishing. Yet no matter how much we try to push things, answers to the really big questions reveal themselves very slowly. Wolves in particular have been highly circumspect when it comes to showing their hand—proving to be an animal of secrets, living in ecosystems still replete with mysteries. The wolf-moose study on Isle Royale, which is the longest running carnivore research of its kind in the world, came up with different answers about wolf-moose dynamics in every decade of the study. In other words, the answers coming from Isle Royale depended entirely on which decade you happened to be in when you asked the question.12
Modern science rests on an insistence that a researcher ask a specific question. Beyond that, some sort of manipulation should be applied—either to the subject or the habitat—preferably with a control site in place. The ultimate ideal would be manipulation with random replication, which means testing your manipulation at more than one site—each of those sites assigned randomly—and at the same time having a control site where nothing is manipulated at all. From a purely scientific perspective, the mainstay of our research here in Yellowstone—using radio collars to track wolves—might be considered only a modest improvement over the kind of plain observation Adolph Murie was so famous for. Yet while this current formula for good science—a mix of manipulation and replication and control sites—makes for a worthy goal, it’s nearly impossible to do things this way here in Yellowstone, given that we’re talking about wolf-prey systems that span thousands of square miles. Besides, in order to secure what would be considered an adequate sample size, we’d need a lot more wolves than we currently have, or will ever have. In short, though we aspire to conduct the strongest science possible here in Yellowstone, we’ll likely always fall somewhat short.
While doing our best to meet modern scientific protocols, I feel it’s also worth recalling what’s best about natural history: going out into the environment and obtaining direct experience through observation, then drawing conclusions from what you see. In that sense we’re trying to be both scientists and naturalists—embracing not just our best researchers but also those men and women living in the stream of people like John Burroughs and John Muir. Population dynamics matter. But then so do individual narratives. For this reason we’ll continue to work hard to keep the Yellowstone wolf reintroduction effort a field-based program, making certain that work plans and ideas flow from the ground up, rather than from the office down.
Portrait of a WolfNUMBER 302
Many park visitors got in the habit of referring to him as “the Casanova wolf.” Park pilot Roger Stradley, meanwhile, who saw 302 many times during our tracking flights together, simply concluded that he was “a lover, not a fighter.” Unlike most wolves, he was hardly a poster child for monogamy. Yet no matter how you describe him, he was without a doubt one of the most interesting wolves ever to hit the ground in Yellowstone.
Born in 2003 to the Leopold Pack on Blacktail Deer Plateau, 302 had a strong start in life. In terms of sheer quality of habitat, the Leopold Pack’s territory rivaled that of any on the northern range. It was spacious and stable, with abundant elk and bison in winter as well as a good population of deer in the summer. Even better, it was remote, having almost none of the human presence that over the years had settled around the packs of the Lamar Valley, making them the most watched wolves in the world.
While most of the wolves we collar during winter operations are pups, still living in the area where they were born—known as their “natal” territory—it would be years before we managed to get a collar on 302. (A genetic profile from blood samples taken during that collaring operation helped us conclude that 302, as well as the brother he was running with, had come from the Leopold Pack.) At the time of that encounter, he was already a big animal, enjoying a physical stature that would prove useful throughout his life. We lost track of his brother soon after he was collared, and to this day aren’t sure what happened to him. But 302, we would follow for years.
As a young wolf 302 bounced around for a while, as young dispersing wolves often do, testing the waters, trying to figure out where to settle, maybe find a mate and start a new pack. Instead, he began what can only be called a highly unconventional life. Instead of starting his own pack, he joined the Druid Peak wolves of the Lamar Valley, which at the time was being directed by the celebrated alpha male, Number 21. Joining another wolf pack as an adult male is a touchy business, to say the least. If you’re lucky, you might just be run off. On the other hand, you might be severely beaten or even killed. Yet 302 just sort of slipped in, never attempting any kind of overthrow, never trying to kick a breeder out of the pack. For a while, wolf 253—aka “Limpy,” who would soon set out for the National Elk Refuge outside of Jackson—chased 302 around, but little came of that. 302 seemed to grow still more content, as if he was happy just to be a member of the pack.
His role in that group was an intriguing one. Though Druid alpha male 21 was in charge when he first arrived, for most of 302’s stay the lead male was number 480—another large, powerful, highly charismatic wolf. It was 480 who basically had the weight of the pack on his shoulders. Meanwhile 302 seemed, shall we say, less than committed. During territorial skirmishes with other packs, we noticed that, more often than not, he just wasn’t interested in participating. In fact most of the time he wasn’t anywhere around. I recall one particular overflight, when we were trying to piece together a territorial battle involving the Druids unfolding on the ground below. I managed to radio track each of the wolves, noting their locations relative to the other pack. Not surprisingly, number 480—the alpha male—was nearest to the skirmish. 302, on the other hand, was a couple miles away, up the Lamar River. This happened time and again. Whenever trouble erupted, 480 took it on without blinking, while 302 was nowhere to be found. (To be fair, in the fall of 2004 number 302 was caught in a trap set by the coyote research team, in the Lamar Valley, from which I managed to release him. Some of the members of the wolf team think that on his return to the Druids following this accident he became even more cautious.)
If this habit of avoiding tense situations was the “not a fighter” part of 302, as some described him, then the “he’s a lover” part was also in full bloom. During the February wolf breeding season, 302 tended to leave the pack—just took off and went visiting. He never took on any of the packs he came across, which is a good thing, since that would’ve almost surely meant death from the dominant male. Instead he hung at the edges, finally luring out with some version of wolf smooth talk subordinate females who didn’t have breeding status in their packs. This would become a pattern in his life. From what we could see he never showed the slightest interest in claiming an alpha slot. Instead, every year during breeding season he would leave the Druids and roam, embarking on an alternative breeding strategy that seemed to suit him just fine. It’s impossible to say how many pups he fathered over the years.
Then the world turned in a dramatic way, forcing 302 to step up to the plate. By the fall of 2008, with the Druid Pack numbering twenty-one animals, many younger members of that pack—four of the five Druid yearling males, along with one or two of the two-year-old females—began leaving the rest of the group for days at a time. Sometimes 302 was along for the ride. They wandered through Slough Creek and onto Hellroaring Plateau—journeys made possible by the fact that several other packs in the region had fallen apart during late summer and early fall. Even so, on October 24 the travelers encountered the Agate Pack, and a skirmish ensued; before it was over an Agate female was dead. Curiously, immediately after the battle we saw the two groups socializing, even traveling with Agate female 692.
Eventually, and in what in the wolf world is a fairly rare event, animals from both Druid Peak and Agate Creek would split from their main groups, joining to start a new pack, which became known as Blacktail. Most of the time wolf packs form by means of a lone male wolf pairing with a lone female. But in the highly competitive wolf environment that now exists on the northern range of Yellowstone, simple pairs of wolves just can’t make it. They’re at almost constant risk of being killed or at least run off by the nearest large pack. But this particular “instant pack” was from the very start big enough to hold a territory together. The four remaining Agate wolves were sent packing, pushed west to the vicinity of the Blacktail Ponds and Chinese Gardens. At first, the new Blacktail Pack roamed widely. In the end, though, they rooted themselves on Blacktail Deer Plateau, the former homeland of the powerful Leopolds. Like several other packs in the area, Leopold had lost much of its strength, crumbling in 2008 in part due to territorial fights, but also because of deadly outbreaks of mange and distemper, the latter having in that year claimed every one of their pups.
302, at this point past his prime, was suddenly surrounded by unrelated females and subordinate males. In other words, he was being handed the alpha male role on a silver platter. And in fact he did end up being lead wolf in the pack. Still, there were lots of days when it seemed he didn’t really want the job, that he was just doing what he had to do, reluctantly. Often he was last up from a rest break, last to get in line for travel—uncharacteristic behavior for an alpha wolf. Still, he did sire more offspring here. Maybe in his advancing years, it wasn’t all bad to no longer have to roam the wilds during breeding season. As it turned out, though, he wouldn’t be long in this role of reluctant leader. In October of 2009 his pack was at the west end of their territory, perhaps patrolling the boundary, when they ran into another pack—one occupying an area farther to the west, in Gardner’s Hole. 302 never came out of the fray.
Though we later confirmed that 302 had died at the hands of other wolves, we’ll never know exactly what happened. As far as we could tell, no other wolf was injured or killed. Perhaps it all came down to his advanced age, which left him less able to fight well or make a fast getaway like other wolves in his pack. Following his death, we did a necropsy, uncovering a whole array of serious skeletal injuries. Maybe it was pain that steered his life in those later years, his aching bones causing him to be the last to rise from rest stops, making him lag behind the others during travel. As of this writing, 302’s skeleton is in the process of being mounted for public display, either in a park visitor center or at the park’s Heritage Center in Gardiner.
By the time of his death, 302 had distinguished himself as perhaps the most reproductively successful wolf in all of Yellowstone. And he got there by abandoning the usual monogamous relationship approach, typical among wolves, for the life of a rolling stone.