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A minute later, after a car zipped past, the wolf reappeared, walked back down the slope and stopped, finally aware of us. It ran back a few steps, then stood looking up the road as if expecting another wolf to appear, then loped into the trees. Downslope, it splashed across a beaver pond and was gone.
The next morning, a blood stain and wolf hair on the highway told that another East Gate wolf was dead. We could not find its carcass, not even a blood trail, and concluded that whoever had hit it had picked it up.
Now the pack was down to two. We caught one of them the next day, an immature male. It was easy to feel sorry for him; he had suffered the anguish of seeing his pack destroyed. Unless the remaining wolf was an adult female, the pack was doomed. Unfortunately, we lost track of him; he slipped his collar. Not that summer nor the next did we hear an East Gate pack. Singles on occasion, but no pack. After that we quit working in this area.
The range of the next pack to the north, the Annie Bay pack, was and still is centred on a clearing where once there had been a lumber mill. Where the mill itself stood is still open grassland after more than half a century. In my student days I lived in an old trailer in the mill clearing and watched the pack from a hill one kilometre away that gave a good view across a burn. That pack was the subject of my first scientific paper: “Observations of Wolves at a Rendezvous Site in Algonquin Park.” Here I witnessed many hours of pup play, the rudiments of hunting behaviour to be used when pups grow older. Over the years, the burn had grown back to young forest, and the wolves had shifted their rendezvous site to the clearings right at the old mill.
Anyone seeing the burn for the first time today could not imagine how different it was thirty-five years before. Back then, a wolf trotting across it was in full view between low blueberry bushes and patches of bracken fern that grew sparsely around blackened stumps and logs. In the burned-over landscape, bluebirds dipped from standing dead spire to spire, and nighthawks dove down on flying insects in the opening. Gone are savannah and field sparrows, replaced by white-throated sparrows. Among the aspen saplings, redstarts and chestnut-sided warblers nest — birds of young forest. Soon there will be ovenbirds and hermit thrushes — species of more shadowy places.
Fire has always been part of Algonquin forests. In an environmental battle zone between major biomes — boreal forest to the north and southern hardwood forest to the south — fire ushers in even more dramatic and longer lasting change than it does in more central places. The first explorers, such as Alexander Sherriff, looking for a safe water route to the west, recorded large areas on their maps as “burned land.” At that time and even earlier, moose and caribou inhabited this highland dome, but no deer. Deer bones are absent in archaeological sites.
With the first loggers in the early 1800s, clear-cutting and burning opened up vast tracts of land. Deer living in hardwood forests to the south extended their range into this food-abundant, early successional landscape. Moose, it seems, may have declined, and caribou vanished. It was a dramatic ecosystem shift, an artificial one, human-caused, with its own built-in, hidden tensions to return to what it was. But rarely can ecosystems duplicate the past.
In the early 1960s, deer greatly outnumbered moose and ranged throughout the park at an estimated density of 5.8 per square kilometre. Cedar seedlings, a preferred food, had no chance to survive except on cliff faces. In many places, forest succession was being retarded by repeated browsing of poplar and maple leaders. Along the highway, traffic jammed up around deer habituated to human handouts, and individual animals were seen so often they were given names.
In contrast, you could travel the park all summer and be lucky if you saw one or two moose, then estimated at only one per six square kilometres. The wolves largely ignored them, eating 80 per cent deer in summer, 90 per cent in winter. It was a deer-dominated system.
You could argue that the ecosystem was artificial then, with so much early-stage forest and with the dominant herbivore being a recent immigrant. Nonetheless, the ecosystem was poised for change — it always is. The climate was warmer than it was when many of the forest giants grew, and beaver had just recovered from a province-wide outbreak of tularemia. Sure enough, in the early 1970s the deer population crashed, victim of winters of deep snow, less logging opening up the hardwoods, too many logged-over conifer stands so crucial to winter survival, rigid fire control, or some combination of these conditions much too complex to sort out. Wolves may have exacerbated the deer decline, once it started, until wolf numbers adjusted downwards too.
Then, for subtle ecosystem reasons or good luck, moose took over, more than quadrupling. Maybe they did so because with less deer there was less brainworm in the forest, or maybe because moose can reach forage higher than deer and can handle deeper snow. Spruce budworm may have helped; it hit parts of the park in the mid-1970s. Graham’s moose-forest analysis showed that some of the highest moose densities were in areas of heaviest budworm infestation fifteen years earlier. Whatever the reasons for the moose eruption, wolves were incapable of preventing it.
Through the 1980s, deer increased in most of eastern North America, the result, many biologists think, of more than a decade of increasingly milder winters and less snowfall. Climate warming? El Niño? In Algonquin, however, the increase was only moderate and occurred only in the eastern and southern sectors of the park.
Finally, in the past few years deer have fluctuated and declined. We examined a range of possible reasons including wolf predation, and then we found the answer. It was not what we expected — that is a later story.
The Annie Bay pack’s rendezvous site at the old lumber mill was used more consistently than any other pack used any site — tradition successfully passed on. Once, shining our flashlight out the truck window, three pairs of wolf pup eyes reflected back from the grasses at the edge of the road. The pups, tiny balls of fur, walked this way and that to get a better look. It was midsummer and we had come upon them by surprise. In a few minutes, their curiosity satisfied, they scampered back out of sight.
We radio-collared three Annie Bay wolves over the years. The first gave us good territorial boundaries for a year and a half before going missing. The second, a young female, dispersed from the park and died a year later from an unknown cause. We found her collar near the town of Wilno.
The third Annie Bay wolf was on the air for three and a half years. She was a yearling when we radio-collared her in 1990. After two years we were forced to stop following her because of budget restrictions; to fly to Annie Bay added half an hour to our telemetry flights. Until then, she had never gone south as far as the park boundary, staying at least five kilometres inside the park. Then in February 1994 a trapper notified the MNR that he had snared a radio-collared wolf adjacent to the park. When Mary and I retrieved it, we were surprised to find it was her. Like so many wolves, her collar, still transmitting, had outlived her.
The next spring we returned to Annie Bay, this time with Wayne Rostad, the host of the popular CBC television program “On the Road Again.” The producer, cameraman, and soundman brought all the paraphernalia with them for night filming: floodlights, big white reflectors, special film. The peepers were going full blast, and a couple of woodcocks were sky-dancing in the dark. Now and then a snipe winnowed by.
There wasn’t the same aura of other times, not with the producer saying “stand here” and the cameraman saying “can we try that again.” To provide a whimsical interlude in the film, we were to “teach” Wayne how to howl.
I howled to show Wayne how to do it. No wolves responded. Then Wayne tried it. Mary tried it. Just the peepers, never missing a beat, and the woodcocks undisturbed.
Halfway up Dickson-Lavieille lakes, the Annie Bay pack’s range abutted the Lavieille pack. With big Lake Lavieille on its west side, this pack ranged to the east among stately red and white pines, some of the most persistent escapees still at large from the logging mills. Fortunately, a new wilderness zone designated there in 1995 has granted them a life-tim
e pardon.
Various student crews worked with this pack and put on five radio-collars over the course of three summers. Mary and I took part in only one capture, made by Jenny and Carolyn. We came to visit them with our veterinarian colleague, Ian Barker, who wanted to inspect our handling and drugging techniques. Ian witnessed the collaring of Lavieille 2, who was lying prostrate and drugged in a grove of balsam firs.
The first summer of tracking showed us a clear demarcation between the boundaries of the Lavieille pack and a pack named Charles Creek to the north. Between them ran two roughly parallel east-west roads only five to eight kilometres apart. The roads were used by logging trucks, wolves, and us. The Lavieille pack claimed the southern-most road and the Charles Creek pack owned the northern road. Two collars on Charles Creek wolves gave us data on their movements. Never did we record an actual meeting of the two packs, but often they were close.
The next summer, the Charles Creek pack stayed a few kilometres to the north, not using their road at all. They were inaccessible most of the time.
The third summer, Charles Creek wolves again stayed to the north, but this summer, Lavieille wolves took over both roads. Had they won a boundary war, or was this an example of “use it or lose it?” If it was the latter, why had the Charles Creek wolves stopped using the southern edge of their territory? They could have travelled across the full diameter of their territory, about twenty kilometres, in only a few hours. The boundary road was not in a prey vacuum; we routinely found moose tracks there, and beaver ponds were plentiful. For whatever reason, ownership had changed.
Lavieille 1 and Lavieille 3 both went off the air only a few months after having been collared. In neither case do we know their fate. Lavieille 2 was hit by a car twenty kilometres south of the park. Lavieille 4, a lactating female when caught, slipped her collar. Lavieille 5 gave us a year, then died at the northeast corner of Lake Lavieille among the big pines. It took a canoe trip by a student crew to recover her collar. Her carcass was too decomposed for us to determine cause of death.
In this transition zone across the Algonquin dome, changes in snow depths and temperatures, logging practices, and fire will shift forest composition as they have in the past, subtly or suddenly. Hidden tensions, coiled for release, lurk in ecosystem gradients found there. With luck, the adaptable wolf will ride them through. Human killing of wolves is a bigger problem.
Recovered now, the East Gate wolves howl again for tourists and take their chances with the wolf killers in the town of Whitney. The Louisa and Little Branch wolves do not have to fear walking into snares so long as they centre their territories inside the park. The Annie Bay wolves will continue to prowl the clearing at the old mill and with luck keep away from the park’s southern boundary. We no longer work with these packs, not because they have no more to tell us, but because of a shortage of research dollars and shifting priorities. People will undoubtedly continue to kill them; we won’t be collecting their carcasses.
LASTING KINGDOM: THE JACK PINE PACK
Dispersers
A desire to leave home is typical of young animals, usually as they become mature. They may need a push, subtle or otherwise, by parents or other group members, but when the time comes, most of them move on.
In leaving, young animals are responding to the dictates of their genes — ancestors who left home contributed more genes to future populations than those who stayed. Against staying is the threat of inbreeding depression. Close relatives may produce sterile or unhealthy young often enough to handicap their genetic future. Also against staying may be a population build-up and overexploitation of resources. By leaving, younger animals and social subordinates normally increase their chances of meeting their needs; inadvertently, they help the entire population meet its needs too.
There is, however, a counter-pressure. Leaving home means going into an uncertain world where chances of getting killed increase. Therefore, competing in an animal’s make-up are the genes of ancestors who stayed, survived longer, and eventually bred.
Highly evolved social vertebrates have an enhanced ability to behave beyond the narrow dictates of their genes and make decisions based upon an assessment of their situation. Young animals may make a pre-dispersal reconnaissance to see if land or mates are available, or if members of other social units accept or repel them. Their sex bears on the decision too; in mammals, usually only males disperse, but that is because the males of most species mate with more than one female. If subordinate males stay home, dominant, multimate males may prevent them from ever breeding. Among monogamous mammals, however, normally both sexes disperse.
Variations in the way animals disperse characterize different species. Dispersal influences social organization, spatial distribution, genetic structure, population size, and even whether a population will persist. Wolf dispersal has been scrutinized intensively, especially in Dave Mech’s twenty — year study in northeastern Minnesota. He and Eric Gese published detailed results along with a review of the observations of François Messier in Quebec, Warren Ballard in central Alaska, Rolf Peterson in southeast Alaska and on Isle Royale in Lake Superior, and others.
Typically, about half to three-quarters of the wolves in a population eventually disperse from their natal pack. Among those who leave, about one-quarter do so as pups (animals less than one year old), half as yearlings, and the other quarter as young adults. Occasionally wolves wait to disperse until they are three or four years old. Young females tend to leave about one year earlier, on average, than do young males. Gese and Mech found that although heavyweight pups were just as likely to stay as to disperse, all lightweight pups dispersed, likely the result of their social inferiority and perhaps resultant food stress.
Most dispersers either establish new packs or, less commonly, join existing packs. Most settle down next to their natal pack or close by, although some young animals travel hundreds of kilometres. Yearlings tend to travel farther than adults. Adults may be more successful in staking out land and obtaining a mate close to home because of their maturity and experience. In dense wolf populations, dispersers have to travel farther to find what they are looking for than in exploited populations with vacant lands nearby. The older a dispersing wolf, the greater its chances of successfully mating.
Dispersal most commonly occurs during the breeding and early denning season from February until spring; some studies describe a second peak of dispersal in October and November.
Dispersal rates are high in both increasing and decreasing wolf populations, presumably influenced by the availability of food. When wolves and prey are increasing, existing packs may be more willing to tolerate new pack formation. When wolves and prey are decreasing, greater food stress within packs may lead to greater intolerance and so greater dispersal.
Dispersal rates are also high in sparse populations and unstable ones. Steve Fritts, who studied both an exploited and then protected population in central Minnesota, found that exploitation increases dispersal by increasing the chances of dispersers finding vacant territories. As follows from his observations, in exploited populations packs tend to be smaller; in unexploited ones, with less dispersal, pack sizes build up.
Non-dispersing wolves are betting on eventually taking over positions of dominance in their natal pack and breeding. More wolves take this option in a non-exploited, dense population where, because of less dispersal, fewer females breed. In contrast, in a heavily exploited Alaskan population, Robert Rausch found that go per cent of females bred.
From these studies we know many facts about wolf dispersal. But how do we interpret them? What do they tell us about wolf societies? The single most interesting feature of wolf dispersal is that rarely do territory holders kill dispersing wolves even though the dispersers are trespassing. Is dispersion an exemption to the fundamentally competitive, territorial system in wolves? Or is dispersion a manifestation of a more flexible social system, sometimes characterized by indifference, sometimes even cooperation? The answer may be based a
s much on expectation and outlook as on fact.
SPRAWLING across the driest parts of the Petawawa sand flats, once a broad, ancient river bottom that drained glaciers to the north, is a forest dominated by jack pines. Dry and hot in summer, even red pines struggle here. White pines have to search for the scattered, higher rocky places where there might be more soil moisture. It is the kind of place for jack pine budworm, a natural monoculture. Because of an outbreak about thirty years ago, a “salvage cut” took place, so the forest still has the scraggly, awkward appearance of youth. That is just fine for spruce grouse, who nest here more abundantly than in other places, and for the flashy budworm warblers such as Cape May and blackburnian.
The Petawawa sand flats form the heart of the Jack Pine wolves’ land. In summer they leave their footprints on the sandy logging roads and in winter trace the creeks and bogs. They range northwest to the Petawawa River, whose waters foam over rocks before disintegrating in extensive Lake Travers. They travel south beyond the hills cradling Dawn and Dusk lakes, two forest teardrops. Several times they denned under a big spruce growing on an old streambank where a creek wound through tangled alders out front.
We became acquainted with these wolves during the first summer of our study. Over the years we radio-collared eight Jack Pine wolves, getting to know some of them well. Then, nine years later the pack vanished, all but one. In that interval, despite suffering their share of losses, the Jack Pine wolves maintained more constant boundaries than any other pack. Now, claiming the same lands, there is even a new Jack Pine pack, different wolves, slightly altered boundaries, same kingdom.
Midsummer heat. Oppressive humidity. Storm-feeling in the forest. I climbed a ridge to a rocky crest overlooking a sweep of pine forest to the hills beyond. The signals of the three Jack Pine wolves came in clearly. Quietly, I searched for a level place to set up my tent.