The Company of Wolves (4 page)

Most of Boyd’s views of wolves were from airplanes. She would see their long purple shadows strung in a line on a frozen lake in the low sun of winter. Sometimes, the shadows would be eight times taller than the standing wolf and would loom up like billboards as she flew toward a snow-covered meadow or lake. A couple of times each winter, she would ski to a location determined a few days earlier by flyover, and happen to reach the spot just as the wolves were passing back through it. “If they detected me, they would disappear,” she says. Or she might see them far ahead, loafing in a meadow or sleeping around a kill, and would stop and watch for twenty minutes or an hour, until she became too chilled to stand still.

Boyd was witnessing a relatively unstudied aspect of wolf nature: the developing edge of a wolf population, the pioneering explorers and settlers of untenanted ground. Ream’s collection of reports had suggested a trickle of wolves coming down into the Glacier area from Canada. Now the wolves were claiming the territory, settling down, having young and forming packs. Boyd tracked and watched. Nowhere else had human observers recognized the pioneering movement and studied it from the first wolf. And as she watched, a distinctive picture of wolf life emerged.

Glacier wolves are big wolves, comparable in size and weight to Alaskan wolves. An adult female weighs 80 to 100 pounds, an adult male as much as 125 pounds. Wolves of desert regions, such as
Canis lupus arabs
, the wolf of the Arabian desert, weigh 50 to 60 pounds
and are small enough to be confused with the jackals or coyotes that share their range. The largest wolf taken in Alaska weighed 175 pounds. Hunters glimpsing such wolves in the woods have sometimes mistaken them for moose. Size is an advantage in bringing down larger prey, defending a territory against rival packs, or contending for standing within a pack, and, to some extent, in retaining body heat in a cold climate; but it is a disadvantage in that it requires more food to meet individual energy needs. In desert regions, prey is not large enough or densely populated enough to sustain large wolves.

Wolves vary in color from pure white to soot black. There are silky gray wolves the color of wood ash, and creamy tan wolves with gray brindled backs. Arctic wolves are mostly whites. The wolves of Glacier are mostly grays and blacks.

Wolves are social creatures, no less convivial and attached to each other than humans. The life of the individual is inextricably woven into the life of the pack. Some wolves travel and hunt alone, but their journeys are probably temporary solitudes that will eventually bring them back to pack life. Or, like Boyd’s original subject, they are dispersers, gamblers on the future of the species, like humans who go off to cross unknown seas or explore remote frontiers; they are, in an evolutionary sense, probes sent off to try to establish wolf genes on new ground. Nineteenth- and early-twentieth-century literary naturalists focused at length on lone wolves. Perhaps the idea derived from our parting view of wolves as we shot and poisoned the last of them into oblivion. Stanley Young’s
Last of the Loners
, a collection of accounts of legendary stock-killing wolves and the trappers who ultimately exterminated them, gave them names and characterized them as individuals alone and at odds with the world. A popular print by Alfred von Kowalski Wierold Zowalski, entitled
Lone Wolf
, shows a wolf standing in the snow on a hill at night, overlooking a small, low-roofed winter cabin with smoke rising from its chimney and a pale light blinking from its window. The picture is allegorical, not of the ravenous wolf on the prowl, but of the outsider looking in on the snug and private comforts of other beings. It hung in ranch houses and back-country cabins all over North America. The pictures and the literary wolves suggest that the lone wolf has become a human idea, a myth that says something about will or fortitude or
one’s own tragically civilized loneliness. The lone wolf is not a bad metaphor for the alienation of modern life, or the isolation of life on the nineteenth-century frontier, but it is an aspect of life that most wolves, tucked as they are into the chatty comforts of wolf society, do not much experience.

Most wolves live in packs of two to twenty, the pack size depending largely on the size of available prey. In Minnesota, where deer are the chief prey, packs number five to ten individuals. Mexican wolves, which feed on smaller, more widely dispersed drylands deer, seem not to occur in packs larger than a pair plus their young of the year. In Alaska, where wolves prey on moose, packs may number ten to twenty. Packs of more than forty wolves have been reported in bison range in northern Alberta, but whether these aggregations are long-lasting is not known.

Though wolf packs are cooperative, they are not democratic: they have rank orders among each sex. Typically, the dominant, or alpha, male lords it over all the other males, and a dominant, or alpha, female asserts her will over the other females. There may be a beta and a gamma, second- and third-ranked wolves of each sex, each imposing some will on the lesser-ranking wolves down through the Greek alphabet to omega. Boyd could read the dominance rankings even from the air. When wolves were spread out in single file in the snow, the dominant males and females carried their tails high, while the subordinates carried their tails low; the lower the tail, the lower the rank of the individual. There were other signs, too. Subordinates would approach higher-ranking wolves and lick at their faces, their heads low, their ears flattened, their tails pressed to their bellies. Or they would roll over in the snow and present their bellies and groin areas to be sniffed. Dominant males and females standing over subordinates in such encounters had stiff, unyielding postures.

The dominance rank order of a pack changes as wolves age or get injured and younger wolves mature and gain strength, confidence, and understanding. Typically, dominance orders are most unsettled early in winter, when there seems to be more fighting. Old dominants may be chased out of the pack or beaten and brought down to submissive roles. Younger challengers may arise, assert themselves, be beaten, and sink back into submission.

Hierarchies are a part of the dynamics of pack splitting and reformation.
In January 1987, Boyd found that Phyllis, the alpha female of the Magic Pack and the wolf collared by McLelland in 1985, had drawn off by herself, either to the edge of the pack or wandering entirely apart. Phyllis had evidently been displaced as alpha female. Boyd had radio collars on a half-dozen wolves in the pack, and she was able to follow Phyllis as she left the pack and went north into Canada, found another mate, and denned. One by one, former packmates peeled off and joined her. Eventually, about half the founder wolves left the Magic Pack to join Phyllis. With the Magic Pack thus split into halves, Boyd and Ream retired the Magic name and designated the two new packs Camas and Sage Creek. In time, she would see at least ten packs form as wolves dispersed from existing packs.

The life of the pack keeps an annual rhythm. Females normally mature at twenty-two months. They come into estrus, or breeding condition, only once a year, in winter. The onset of estrus is gradual, and early in the season, before females are fully fertile, subordinate males may mount even high-ranking females, but they do not actually breed, because the females have not yet ovulated. As the dominant female becomes fertile, both she and the alpha male become increasingly aggressive toward subordinates. Something—perhaps the stress from this aggression—keeps subordinate females from becoming fertile. As she becomes ready to breed, the alpha female secretes a pheromone that causes the alpha male to become possessive and to guard her from subordinate males. Around the end of February, the alpha male will mount her, and during intercourse the bulbous end of his penis swells so that they are locked together or “tied” for up to thirty minutes. After they have tied thus once or twice, a firm bond seems to form. Once that has happened, the pack begins to calm down. There is less competition for status, and roles are generally settled for the time being. One way of viewing the returning peace is to say that the fighting is not so much over rank as over the right to reproduce. Subordinate males may mount and copulate with the alpha female after that, but the likelihood of conception so late in estrus is small. Usually, a pack produces only one litter each year, and that litter comes of the mating between the alpha male and the alpha female, but there are exceptions: in captive packs, subordinate females have borne litters alongside of or in place of the litters of
alpha females. The bonded alpha pair may remain together for years, until one of them dies or is displaced from the top ranking by another wolf.

Gestation takes sixty-two to sixty-three days. In April or May, the dominant pair may draw off and den together, perhaps using a den that has been used many times before. The Magic Pack’s 1986 den was in a thick stand of willows at the edge of a marsh, and the entire pack remained with the alpha pair. There the wolves dug tunnels and nesting chambers twelve feet into the hillside. The opening was so narrow that Boyd could only push her head and shoulders in and measure by pushing a flashlight and steel tape measure ahead of her. She thought it remarkably clean and odorless, with no scats or bones, no sign of wolves other than a few hairs rubbed onto the tree roots on the ceiling. The Glacier Park litters were born in April and May and numbered five to seven black, gray, or multi-colored pups. Wolves in the Arctic give birth as late as June, and those living in places other than Glacier have had litters with as many as thirteen pups. While the young are unable to hunt, one parent may stay with them as the other hunts (either parent may hunt), or the pups may be left alone, even in bad weather. The mother, however, must return to nurse pups in the den for thirty-four to fifty-one days. The successful hunter brings food back to the den in its stomach and regurgitates it to the waiting parent. Occasionally, a subordinate adult may stay with the young while both of the parents hunt, a habit some wolf biologists refer to as “aunting.” Boyd found that widowed males or females like Kishinena successfully reared the young when a mate was killed, even without the help of aunts and uncles.

A pack is likely to consist of the alpha pair, its young of the year, and other adults, presumably the offspring of previous years. While the mated pair den, the other adults may disperse and hunt in smaller groups or as solitary individuals. Spring and early summer are times of plenty for wolves, since deer, elk, moose, and caribou are calving and the young herbivores are easy prey. David Mech found that in summer wolves on Ellesmere Island hunted as individuals as much as 80 percent of the time.

At about two months of age, the pups emerge from the den, and the adults move them to a meadow or an open area near dense forest or other cover, which biologists call a “rendezvous site.” With
moose, caribou, or deer calves now large enough to be more challenging prey, the pack may now reassemble around the rendezvous site, and leave the young there, sometimes with a subordinate adult, while adults go off together to hunt. And when parents or other adults return from a successful hunt, the young mob them, whining and licking their faces, thus stimulating them to regurgitate partially digested meat for them. A pack may change rendezvous sites several times during the summer as they follow prey or are disturbed by humans. By the end of summer, the young are able to go out hunting with the adults, and the pack is on the move as a group again.

Packs possess and defend territories from other wolves. We think wolves keep territories either to protect den sites or to conserve hunting opportunities, and that the abundance of prey generally defines the size of a territory. On Arctic islands where musk oxen and snowshoe hares are the prey, a pack may cover several thousand square miles; one Ellesmere Island pack covered 5,000 square miles in a six-week period. In northern Minnesota, where deer are more densely populated, a territory may be 50 to 100 square miles. In Alaska, where the prey is moose, a territory may be 800 square miles. In northern Montana, where prey is elk and deer, Boyd found territories are typically 300 to 400 square miles. In winter, the wolves may concentrate in small parts of those territories, because the wintering deer and elk concentrate in the river bottoms and adjacent hillsides. Territories change size and shape from year to year. Resident wolves scent-mark heavily at the boundaries of their territories, and trespassing wolves mark assiduously when they stray inside another pack’s domain. It is as if a wolf thus leaves a string of boasts and threats on the ground to taunt and intimidate other packs and keep them out of its larder. Wolves in Alaska and Minnesota have been known to kill neighboring wolves that strayed into their territories. Boyd has, in fourteen years, found only one case of wolves killing wolves in the Glacier area. “I think that’s because there is a low density of wolves, a high density of prey, and a lot of unoccupied range,” she explains.

In the wild, wolves probably do not often live more than ten or twelve years, although in captivity wolves have lived as long as sixteen years. In Alaska, the average age of an adult wild wolf is three to four years, and only a few live to be ten. Normal birth rates can double
the number of wolves each spring, but by winter natural mortality has eliminated 50 percent—chiefly young wolves and old ones. Some die of starvation when they are so badly injured by moose or caribou that they can’t hunt. Wolf skulls have been found with holes kicked in them by deer. Some starve when hard winters reduce prey populations to levels that won’t sustain the pack. Some kill each other in territorial and status battles. Bears have been known to dig into wolf dens and kill their pups. Wolves have also died in avalanches or falls through ice. Then there are human-caused fatalities. Wolves die of diseases such as rabies, distemper, and canine parvovirus, brought to their world by domestic dogs. Humans shoot, poison, snare, and trap them. In 1989, all of the members of the Wigwam Pack suddenly vanished, presumably poisoned. There were no operating radio collars left in the pack, and repeated searches for tracks and howls failed to turn up any trace of wolves. In 1991, the Headwaters Pack, which had formed in 1987 in Canada, disappeared: Boyd retrieved five of their bodies and concluded that they, too, had been poisoned. About 25 percent of the wolves born into the Glacier-area population die of trapping, shooting, or poisoning.