Wolves on the Hunt The Behavior of Wolves Hunting Wild Prey
by L. David Mech, Douglas W. Smith and Daniel R. MacNulty
University of Chicago Press, 2015
Cloth: 978-0-226-25514-9 | Electronic: 978-0-226-25528-6
DOI: 10.7208/chicago/9780226255286.001.0001


The interactions between apex predators and their prey are some of the most awesome and meaningful in nature—displays of strength, endurance, and a deep coevolutionary history. And there is perhaps no apex predator more impressive and important in its hunting—or more infamous, more misjudged—than the wolf. Because of wolves’ habitat, speed, and general success at evading humans, researchers have faced great obstacles in studying their natural hunting behaviors. The first book to focus explicitly on wolf hunting of wild prey, Wolves on the Hunt seeks to fill these gaps in our knowledge and understanding.

Combining behavioral data, thousands of hours of original field observations, research in the literature, a wealth of illustrations, and—in the e-book edition and online—video segments from cinematographer Robert K. Landis, the authors create a compelling and complex picture of these hunters. The wolf is indeed an adept killer, able to take down prey much larger than itself. While adapted to hunt primarily hoofed animals, a wolf—or especially a pack of wolves—can kill individuals of just about any species. But even as wolves help drive the underlying rhythms of the ecosystems they inhabit, their evolutionary prowess comes at a cost: wolves spend one-third of their time hunting—the most time consuming of all wolf activities—and success at the hunt only comes through traveling long distances, persisting in the face of regular failure, detecting and taking advantage of deficiencies in the physical condition of individual prey, and through ceaseless trial and error, all while risking injury or death.  

By describing and analyzing the behaviors wolves use to hunt and kill various wild prey—including deer, moose, caribou, elk, Dall sheep, mountain goats, bison, musk oxen, arctic hares, beavers, and others—Wolves on the Hunt provides a revelatory portrait of one of nature’s greatest hunters.


L. David Mech is a senior research scientist with the US Geological Survey and an adjunct professor in the Department of Fisheries, Wildlife, and Conservation Biology and Department of Ecology, Evolution, and Behavior at the University of Minnesota. He is the author or editor of many books, including Wolves: Behavior, Ecology, and Conservation, coedited by Luigi Boitani and published by the University of Chicago Press. Douglas W. Smith is a senior wildlife biologist and the Wolf Project Leader in Yellowstone National Park. He is coauthor most recently of Decade of the Wolf: Returning the Wild to Yellowstone. Daniel R. MacNulty is an assistant professor of wildlife ecology at Utah State University.


“Very detailed. Never before has the predatory behavior of any carnivore been presented in such depth. Wolves on the Hunt is a contribution not just to our knowledge of the wolf but to our understanding of predation in general. The authors, experts in wolf predatory behavior who are in the best position to interpret these data from a scientific perspective, review a great amount of information and add an impressive number of accounts of hunting events observed by very few people. Their interpretations of the appropriate literature are clear and elegant. Very well written, easy to read both for specialists and for the general public interested in wolves and wildlife, Wolves on the Hunt is unique.”
— Juan Carlos Blanco, former adviser to the Ministry of the Environment on the Coordinated Plan for Wolf Conservation in Spain

“This exhaustive account of wolves hunting and killing wild prey could only be compiled by the foremost wolf biologists of our day—Drs. Mech, Smith, and MacNulty.  The easy-to-read book cites all the primary and secondary literature as well as many previously unpublished observations. Wolves on the Hunt will not only fascinate biologists and those teaching wildlife management but also the general public, including outdoor, environmental, and hunting groups. These detailed observations of predation let us imagine the struggles that our ancestors must have encountered as we competed with wolves to become the earth’s supreme hunters of ungulates.”
— Ed Bangs, US Fish and Wildlife Service, Wolf Recovery Coordinator from 1988 to 2011

“In reading Wolves on the Hunt you will learn that death has shaped life for millions of years. You’ll learn that no activity is more important to the wolf than predation; and although it’s a tough and frustrating habit that often fails, wolves survive only because they refuse to give up. By shedding light on these and other important findings, Wolves on the Hunt will be incredibly valuable to conservation scientists and citizens alike who appreciate wild places and wild things. It’s a great illustration of the constant battle between predator and prey and of dogged determination.”
— Ted Turner, Chairman, Turner Endangered Species Fund

“Across decades of writing about wolves and the science associated with their study, I’ve seldom encountered a more gripping opening to a natural history book. . . . Wolves on the Hunt is an in-depth analysis of how wolves kill prey to survive. This new book could not come at a better time. Even though the year is 2015 there remains in the American West some pretty puritanical notions about alleged wolf behavior that have little basis in reality. . . . Mech, considered the world’s foremost wolf authority, and his colleagues deliver a hair-raising and at times grim narrative about how lobos stalk. . . .  No matter what lobo camp you’re in, you’ll find Wolves on the Hunt to be endlessly fascinating reading.”
— Todd Wilkinson, Jackson Hole News&Guide

“For all wildlife lovers, this is a must read.”
— Melanie Gade, Defenders of Wildlife blog, “Weekly Wolf Wrap-Up”

“Fascinating. . . . Loaded with first-hand accounts of the various stages of gray wolf (Canis lupus) hunting, chronicled throughout mostly North America, the book is illustrated with a captivating collection of photographs and informative comparison data charts. . . . A celebration of . . . the emerging knowledge base about wolves.”
— David Kline, International Wolf

“A gorgeous new book . . . , which represents in one slightly oversized popular volume some of the most comprehensive research to date on the way wolves hunt their prey. . . . It’s written artlessly but directly, with the aim of updating and broadening some popular misconceptions about the way wolves operate in the wild. As a work of natural history, neither it nor anything else can match the lyricism of Barry Lopez’s Of Wolves and Men, but as a general-audience monograph, it’s one of the most valuable works of science-writing to appear this year. Kudos to the folks at the University of Chicago Press for giving it such a handsome volume.”
— Steve Donoghue, Open Letters Monthly

“Three experienced wolfy folk, scientists to the bone, with such amazing and lengthy exposure to wild lupines, were always going to produce something fascinating and valuable. I was not disappointed. . . . It reminds us . . . that science, rightfully, replaces assumptions and theories with fact. . . . An important reminder that to love the wolf, it is best to appreciate the whole animal—whether that be fairytale forest shadow, hunter or socially competent family-orientated creature. This impressive book is one for academics, scientists but also for the curious. . . . A  book to admire and one that should make us appreciate that the wolf does not have an easy life, even if it is an apex predator.”
— Wolf Print

“Public sentiments over wolves are polarized in the United States: many view wolves as icons of the wild; others consider them the epitome of evil. Significant misconceptions exist over how wolves hunt and kill and what they kill. The authors provide clear answers to these questions, using evidence. . . . Carnivore biologists, particularly those focused on canids, will enjoy it. . . . Recommended.”
— J. Organ, University of Massachusetts Amherst, Choice

“To be honest, I was a bit giddy having the opportunity to review Wolves on the Hunt. . . . The book is a fascinating account. . . . Each chapter is extremely detailed and exhaustive, covering all known wolf prey and how they hunt them. This truly is the capstone to first author Mech’s outstanding >55 year career studying wolves, and the painstaking time involved in writing this all-encompassing book on wolf predation with first-hand . . . descriptions of wolves hunting various prey is a tribute to all three authors. It takes endless hours of dedication and perseverance to make these observations.”
— Jonathan (Jon) Way, Eastern Coyote/Coywolf Research, Canadian Field-Naturalist

“Highly useful for defining research questions and informing conclusions from such studies of wolf hunting behavior. Most investigators of these studies will be lucky to witness the pursuit of wolves just once even though this is their focus. Accordingly, this book will be a valuable reference (in more than 1000 hours of radio track­ing wolves and moose, I have witnessed only three wolf-prey interactions). I expect the book to be of broad interest as well because the polarizing nature of wolves is due, in part, to their hunting and predatory behavior. As someone who participates in wildlife management meetings where wolves and their prey are common topics of discussion, I can personally attest to the latter. Stories are shared regu­larly at these meetings, but usually these stories are full of hearsay and innuendo with little fact. The facts contained within this book can inform these discussions, with the ulti­mate goal of fostering a better understanding of wolves and their interactions with prey.”
— Bryce C. Lake, US Fish and Wildlife Service, Yukon Flats National Wildlife Refuge, Arctic

“[One of ‘The Best Books of 2015: Nature!’]. . . . It’s not often in the world of nature-writing that readers get a chance to read a kind of summation written by the single most knowledgeable expert on a given subject, and in 2015 it happened a few times. Including this great book based in such large part on the research, insight, and vast personal experience Mech brings to the subject of wolves.”
— Steve Donoghue, Open Letters Monthly

“The authors represent three generations of career wolf ecologists. . . . This book is indeed unique and will be of interest to many readers, including ecologists and other individuals concerned with wolves and more broadly with wildlife, wilderness, and animal behavior and conservation. . . . A highlight of the book is its superb photography. The images are vivid, graphic, and enthralling. Poignant images are used to carefully point out, convey, or highlight hunting principles or strategies. As also explained in the book, a colossal network of volunteers has been instrumental in collecting the wolf hunting accounts. I have personally witnessed all this effort in the field, although I have not collaborated with the authors directly. I have been there, in Yellowstone and at other field research sites, and I have seen the volunteers, the three authors of this book, and also the wolves and prey, all in action. Readers will be glad that all this finally ends up in a such a cohesive book.”
— Marco Musiani, University of Calgary, Canada, Ecology

“Among the many hotly debated topics related to the appearance of dogs in the lives of humans is how often and where it first occurred. . . . We learn from Wolves on the Hunt that while wolves appear excellent at finding and trailing game, they are not very good at making the kill, succeeding perhaps half the time. It is dangerous work at which humans with their weapons excel. Imagine the scene: Human hunters locate wolves on the hunt by watching ravens who are known to follow them. Human hunters move in for the kill and take as many animals as they can. If smart, they might share immediately with the wolves. If not, the wolves might consume what the humans do not carry off or follow them back to their encampment to take what they can. The rest is a tale of accommodation through socialization—the ability to bond with another being—and all that entails.”
— Mark Derr, The Bark

“If we underestimate prey animals in ecology, we risk overestimating predators’ impact on prey populations and on landscapes. . . . This extraordinary book . . . captures that complexity very beautifully. The authors are three of the most experienced wolf biologists in the world. They have conducted many fundamental studies of wolf biology and together they have seen wolves actively hunting more than anyone in their field. The volume centers on rigorous analysis but is enriched and enlivened by firsthand observations and photographs that are meticulously curated to help readers see the hunt for themselves. The result is an already classic account of an archetypal predator-prey interaction. But, to me, the book’s most important value may be to demystify the wolf at the very same time it builds our respect for the animal and its sophisticated prey. That is the greatest honor the creatures within its pages can be paid.”
— Arthur D. Middleton, Yale University, Quarterly Review of Biology





DOI: 10.7208/chicago/9780226255286.003.0000
[Wolf, Canis lupus, Predation, hunting behaviour, ungulates, defensive behaviour, adaptations, prey]
This chapter reviews the literature on wolf hunting behavior and then discusses the physical and behavioral adaptations of wolves to hunting large ungulates, the wolves' primary prey throughout the world. Living in packs, being able to travel many kilometers daily, possessing keen eyesight, hearing and especially olfactory senses all allow wolves to find, chase, confront, and kill enough prey to survive. On the other hand, prey animals have also evolved keen senses which, along with sharp or heavy hooves and antlers, herd living and various types of elusive behavior, allow them to minimize their chances of falling victim to wolf predation. (pages 1 - 9)

DOI: 10.7208/chicago/9780226255286.003.0001
[white-tailed deer, Odocoileus virginianus, Wolf, Canis lupus, Predation, hunting behaviour, Minnesota, Superior National Forest, prey]
Wolves prey on white-tailed deer primarily in the northern U.S. and southern Canada. The whitetail is one of the wolf's smallest hoofed prey and as such might seem especially vulnerable to wolves. However, the keen senses of the deer, its fleetness, and its sharp hooves and antlers all play a role in helping it survive wolf predation. The deer's ability to herd up in winter and to space out singly in summer when its newborn fawns are most vulnerable minimizes chances of wolves to cash in on any easy pickings. Wolves manage to find some vulnerable individuals both in summer and winter by constantly traveling and making many attempts to chase and catch deer, as documented in the many hunts described in the chapter. Through sheer persistence and patience, wolves eventually end up with individual deer they can kill. (pages 10 - 27)

DOI: 10.7208/chicago/9780226255286.003.0002
[Moose, Alces alces, Wolf, Canis lupus, Predation, hunting behaviour, Isle Royale, Denali National Park, prey]
Moose are one of the largest of the wolf's prey. Their sheer size and strength help make them formidable to wolves. Large, blocky-but-sharp hooves form the animal's main defense, and they have killed or injured many a wolf. If moose detect wolves far enough away, they usually just flee out of the area, thus avoiding an attack. However, if the wolves sense the moose soon enough, they give chase. If they manage to catch up to the moose, that animal may stop and challenge the wolves. When a moose stands its ground while confronted by wolves, it does not take the predators long to realize that moose is not to be reckoned with, and they move on to try some other individual. This sequence goes on and on until wolves find a moose that continues running. Then by first attacking its rump and spending hours or sometimes days tearing at it and weakening it, the wolves finally succeed. This chapter includes many descriptions of wolves hunting moose, both successfully and unsuccessfully. (pages 28 - 45)

DOI: 10.7208/chicago/9780226255286.003.0003
[Caribou, Rangifer tarandus, Wolf, Canis lupus, Predation, hunting behaviour, Denali National Park, Migration, prey]
Caribou, or reindeer in the Old World, probably are the most common free-ranging wolf prey on a global basis, for they have a circumpolar distribution as does the wolf, occurring generally north of about 55° N latitude. Unlike most of the deer-like ungulates, both male and female caribou sport antlers. Caribou are also strong herding animals and most are nomadic; some are migratory. All these traits help reduce the vulnerability of caribou to wolf predation. At the least these characteristics force wolves to spend considerable time and travel merely to find caribou. Wolves, in turn spend that time, and they travel that much such that they can locate herds or straggling caribou enough times to feed and survive, albeit usually at some of their lowest densities. The many well-documented hunts in this chapter make clear that the hunting abilities of wolves and the defensive traits of caribou are barely evenly matched. (pages 46 - 62)

DOI: 10.7208/chicago/9780226255286.003.0004
[Elk, Cervus elaphus, Wolf, Canis lupus, hunting behaviour, Yellowstone National Park, red deer, predation, prey]
In the western U.S., many parts of Canada, and in various areas of Eurasia, wolves prey on elk (red deer in Eurasia). However, until wolves were reintroduced into Yellowstone National Park in 1995 and 1996, little was known about how wolves hunt elk. Since the Yellowstone reintroduction, considerable new information has become available, and this chapter synthesizes that. Numerous descriptions of wolves hunting elk, along with many photos and videos pervade this chapter. As with other prey, elk are not easy for wolves to kill; in fact elk have killed several wolves. Nevertheless, wolves usually manage to persist until they find individuals among elk herds that present the least risk, and the wolves end up with them. (pages 63 - 106)

DOI: 10.7208/chicago/9780226255286.003.0005
[Dall's sheep, Ovis dalli, bighorn sheep, Ovis Canadensis, Wolf, Canis lupus, Predation, Prey, hunting behavior]
Highly specialized for inhabiting steep mountainsides, both mountain sheep and goats present a unique challenge to wolves seeking them. These sheep and goats rely almost exclusively on their ability to maneuver among the rocky crags and pinnacles to avoid wolves hunting them. Adolph Murie in 1944 observed many hunts by wolves trying to catch Dall's sheep, and other researchers since then have added to our knowledge of interactions between wolves and Dall's sheep, bighorn sheep and even mountain goats. This chapter includes these first-person accounts. They show that wolves have the best chance of catching the mountain dwellers if the wolves can catch them by surprise either below the mountain or by approaching them from above. (pages 91 - 107)

DOI: 10.7208/chicago/9780226255286.003.0006
[Bison, Bison bison, Yellowstone National Park, Wood Buffalo National Park, European wood bison, Wolf, Canis lupus, Predation, hunting behaviour, prey]
Bison constitute the largest and most formidable prey of wolves. Although bison were originally one of the most numerous of the wolf's prey, especially on the Great Plains of North America, now wolves hunt them primarily in Yellowstone National Park and Canada's Wolf Buffalo National Park, as well as in a few countries of Europe (European wood bison). The animal's sheer size and strength and its tendency to live in herds keep adults safe from wolves except under certain conditions such as deep snow or when old or decrepit. Calves too can be vulnerable when too far from their cows or the herd, or if wolves can maneuver them away. As with wolves preying on adult moose, attacks on bison generally take hours or even days, as the descriptions, photos, and videos in this chapter describe. (pages 108 - 128)

DOI: 10.7208/chicago/9780226255286.003.0007
[Muskox, Ovibos moschatus, Predation, Prey, hunting behaviour, wolf, Canis lupus, Arctic, subarctic]
Although smaller than bison or moose, muskoxen are also one of the most difficult animals for wolves to kill. They inhabit the arctic and subarctic primarily in Canada and Alaska, usually live in herds, and roam nomadically across the tundra. These tendencies force wolves hunting muskoxen to search far and wide to locate them. Then when the wolves attack, the very-long-shaggy coats of the muskoxen help protect them from the wolf's lunging bites, and their recurved horns and sharp hooves can also be lethal to wolves. The descriptions of wolves hunting muskoxen in this chapter involve attacks both on adults and calves and show that the exquisite adaptations of wolves to hunt and kill are put to the test in the barren habitat of the muskoxen but that they meet that test just enough to let both species survive. (pages 129 - 143)

DOI: 10.7208/chicago/9780226255286.003.0008
[Wolf, hunting behaviour, predation, beaver, pronghorn, salmon, wild boar, seal, arctic hare, prey]
In most areas, the wolf's primary prey consists of hoofed mammals. However wolves will eat almost any kind of animal and even various fruits and berries. In a few areas, non-ungulates make up important parts of the wolf's diet, at least during some seasons. For example beavers are usually locked beneath the ice during winter but can supply considerable food during other seasons. Similarly arctic hares, salmon, and seals can help supplement the wolf's diet and perhaps carry them over periods when their ungulate prey are less available. This chapter includes accounts of wolves hunting the above species as well as other miscellaneous prey such as pronghorn, wild boars, wild horses, waterfowl, and small mammals. Few accounts exist on each of these species, but those that do document that the wolf is an opportunist, ready to catch and kill whatever prey is available and vulnerable. (pages 144 - 158)

DOI: 10.7208/chicago/9780226255286.003.0009
[Wolf, Canis lupus, Predation, hunting behaviour, prey, parasites, disease, malnutrition]
This concluding chapter discusses how, despite all the defensive traits and behaviors that the wide variety of the wolf's prey species possess, wolves are still able to overcome enough prey to survive. The wolf's own superb adaptations for sensory abilities, persistence, patience, strength, speed, stamina, teeth, and bite strength all play a role. However, of critical importance is the fact that all prey species sooner or later develop vulnerabilities. They live tough lives and, if relatively unscathed for most of their lives, at least they get old. Many of the wolf's kills involve old individuals. In addition disease, parasites, malnutrition, injuries, inter-generational deficits, and other vulnerabilities beset individual prey. To survive, the wolf must be highly adept at finding these individuals, for they form the animal's lifeblood. (pages 159 - 164)

Appendix: List of Scientific Names of Birds and Mammals Mentioned

Literature Cited

Author Index

Subject Index