Wolf Country
Page 16
Possibly, canine parvovirus is a key player in the web here too, accountable for the unusually low percentage of yearlings in the population. Without capturing and taking blood from very young pups, we will never know, but to attempt such a study would be too disruptive to the wolf population.
These intricacies in the operation of the large mammal component give us plenty to think about up there on the ridge over McDonald Creek, our “ecosystem contemplation place,” always to the background music of a red-eyed vireo. Underlying how things shift and change, in 1997 we monitored a different pack, the Zigzag Lake pack, from the same place — there had been a boundary shift. The subtle workings of time re-adjust wolf territories.
Time does more than that. For all living things in Algonquin Park it resets averages, weeds out the weak, selects genes, imposes rhythms based on fire frequencies and wildlife cycles that reverberate right down to the soil.
Tree diseases such as jack pine budworm and white pine blister rust come and go, and the bacterial disease tularemia knocks back the beaver population on occasion. Winter ticks have their variable effect on moose depending on the timing of snowmelt. Climate influences seed production and germination. Snow stresses female ungulates, causing them to abort fetuses or give birth to young that will not live long. Over time, all these things jostle the ecosystem web.
Television hosts often ask us why we are interested in wolves. We know the sort of answer that is expected. “Oh, I fell in love with them when I was a child” — or some such thing. Sometimes a host’s eyes glaze over just a bit when we try to explain that the marvel is the whole web and the wolf’s place in it, not just the animal itself. Wolves in zoos — isolated, out of context, disconnected — are not as interesting.
But wolves in the web are. Our data do not support a strong top-down wolf influence in Algonquin Park. For that to happen, wolves would have to be changing the numbers of their prey or altering their distribution and movements, which in any major way they do not seem to do.
The ungulate-vegetation link, however, runs both up and down, differing in the Petawawa and Bonnechere valleys. Spruce budworm is a bottom-up strand influencing the forest first, which in turn influences moose, then wolves. Logging is bottom up: forest, ungulates, wolves. Deer and moose hunting by humans may run up to influence wolves, down to influence the forest. Wolf killing by humans is a top-down effect.
We do an injustice to nature to even search for simple relationships. In any web, every strand plays a part.
FOYS LAKE PACK — SUPRA-ORGANISM
The Best-Fit Group
Scottish biologist V. Wynne-Edwards thrust people interested in ecology and evolution off on a decade-long tangent with his substantial book Animal Dispersal in Relation to Social Behaviour. I read it as a budding biologist, the book travelling with me as I searched for a suitable Ph.D. thesis topic related to the hot question of how animals regulate the size of their populations, if indeed they do. Jim Bendell, my supervisor at the University of British Columbia, pushed the concept that ideas and principles count in understanding ecology, not species. Species just play them out. He wanted me to find a species to test Wynne-Edwards’ ideas.
The book impressed me then and still does, though Wynne-Edwards eventually backed away from his central premise and others replaced it. Ironically, wolves, and not rock ptarmigan that I studied, have turned out to be better animals for scrutinizing his ideas.
His proposition, simply put, was that natural selection works on groups of animals rather than on individuals. Groups of animals are like supra-organisms. Survival of the best-fit group is the way of things, not only survival of the best-fit individual, as Charles Darwin explained.
Wynne-Edwards bolstered his notion with explanations for a whole range of group social displays, or behavioural rituals that animals perform, that, until then, seemed to have no purpose. So pervasive are such displays in animal societies, he thought, that surely they have some survival value. He proposed that they provide the members of the group with a sort-of self-census that results in social pressure. If the group appears too large for available resources, some animals disperse. These dispersers, the “have-nots,” are the losers, sacrificing their individual fitness for the good of the group. They are destined to experience lower-quality habitat or greater susceptibility to predation, resulting in either lower breeding success or death.
Anything even remotely anti-Darwinian is certain to be scrutinized by the scientific community. Natural selection working on the group? The critical evidence, to Wynne-Edwards and others, was self-sacrifice for the good of the group. The evidence gets tangled up, however, with cooperative behaviour.
Nobody doubts that cooperative behaviour conveys advantages, but to whom? To the group, or to the individual in the group? It might be worthwhile for an elk to stand guard as a herd flanker watching for wolves while the herd members graze, if in so-doing that elk also benefits from a better chance of escape. That elk might benefit, at other times, from reciprocal cooperation when others stand guard. If the group is beneficial to an elk, it is worthwhile to invest some effort in its welfare. In that way, cooperative behaviour is universally explained as conveying advantage to individuals in the group.
That sort of cooperative behaviour is abundant but below the level of self-sacrifice. The guard-elk would not stand guard if the price was to be its own death. Unfortunately, self-sacrifice has been seen as the only true test of group as opposed to individual selection, rather than its most dramatic example.
Wynne-Edwards’ idea stimulated a concerted search for self-sacrifice among animals — “altruistic behaviour.” The result? Not much of it was found. Yet, where found, there were common circumstances. It showed up in kin-related, genetically affiliated groups, especially in maternal behaviour. An example of this is a mother killdeer’s broken-wing display to lure a predator away from the nest that holds more than two chicks, so contains more of her genes than she herself possesses. Cases of altruism had to make genetic sense: more genes would remain in the offspring than in the self-sacrificing individual. Such examples resulted in the notion of “kin selection,” promoted, in part, in another huge book ten years later called Sociobiology, by renowned Harvard biologist E. O. Wilson.
While altruism is a reasonably sure sign of group selection, survival of the best-fit group does not depend on it. All that is necessary is to find groups of cooperating animals working strategically together, especially with some division of labour, whose competitive success against other groups is bound together by one another’s skills, and who to some degree share a common fate. Such a group — its pool of genes — is more likely to persist.
It falls to the lot of three groups of people — those studying social mammals, social insects, and human societies — to further consider group selection, thirty-five years after it may have been prematurely rejected.
GRAHAM’S VOICE crackled in over the static of the two-way radio. The Cessna had just cleared a ridge and was in view, crawling along the hazy blue sky looking like one of the dozens of mosquitoes that buzzed around our heads.
“I’m onto Basin 3’s signal to the north. I’ll be back in a few minutes.” The plane banked and inched its way towards the horizon.
Thursday, July 19, 1990, 7 A.M. We were camped in an abandoned, raspberry-choked log landing. An overgrown spur road led out to the hydro line, which cut a wide, ugly swath through the forest. Incongruous in a park, three ranks of steel towers march across hills from the Chalk River dam on the Ottawa River to join the power grid somewhere to the south. Stark brown pine saplings spray-killed by Ontario Hydro stick up through grasses that cover much of the strip. Naked rocks lie obscenely exposed.
Incongruous, too, is the plant diversity the hydro line adds to the east side of the park, attracting foraging deer and moose, providing black bears and pine martens with raspberries, and offering an easy path for wolves. Ignoring many square kilometres of forest, the Foys Lake wolves moved into a bog rendezvous site
that extended partway under the wires.
The pack knew we were there, camped a kilometre away. One wolf found us by accident. A summer-day shower had broken the heat, and we were sitting in the truck, doors open, writing up our notes. A bedraggled-looking wolf, head down, walked slowly into the clearing, approaching to within ten metres before the image of the truck caught the corner of its eyes. It looked up, startled. Reflected light on the windshield must have hidden us, because it did not run. Instead, it raised its head and scented the air. In a moment, caution made it turn. Glancing over its shoulder, it walked slowly back the way it had come.
That night a Foys wolf investigated us while we slept; in the morning, big wolf tracks circled our tent.
The plane appeared again and Graham reported, “Basin 3 is up the hydro line six kilometres from the rendezvous site. Foys 3 is back in the logging operation two kilometres southeast of you. Foys 2 and Foys 4 are seven kilometres southwest along the Bonnechere road. Grand 3 has moved four kilometres straight west from last night and now is trespassing in Foys territory. She is beside a bog on a hill. I can’t find Foys 1. I’ll be back again in four hours.”
We spread the topographic map on the hood of the truck and plotted the coordinates for each wolf. After eight consecutive flights, we were getting exciting data. Pack members seemed to be coming and going individually or in small groups, covering their entire territory day and night. Since the previous evening, Basin 3 had moved seven kilometres and Foys 2 eight kilometres to end up twelve kilometres apart. Foys 2 and Foys 4 had left the rendezvous site where they spent the previous night and had also separated.
With five radio-collared wolves in one pack on the air, we had a chance to learn how extensively Algonquin wolves move during the day, whether they travel together or separately, and how long they remain away from the rendezvous site. They also would help us to assess differences in movements of individual wolves. By that time we were pondering the idea that a wolf pack may be acting like a supra-organism and, if so, that there may be some validity in the controversial idea of survival of the best-fit pack — natural selection working not only on the individual, but on the group.
We had booked the Cessna for a week. Volunteer pilot Hank Halliday flew it down to the abandoned Bonnechere airstrip where he and Graham camped in the jack pines beside the runway. They were to fly four times a day while Mary and I camped close to the rendezvous site to monitor movements there. We also planned to check out possible kill sites from map coordinates radioed down to us.
It was a week of relentless sun, flies, and heat except for one morning shower and one violent thunderstorm. Only late at night did it cool off. Some mornings the hills cradled a mist, delaying take-off time. Usually by 9 A.M. the sun cleared away the nighttime humidity and heated the tent up enough to fry any sandflies inside. We lay under a pine at the edge of our unscenic clearing, waiting for the next flight, checking the signals every fifteen minutes. At the abandoned airstrip, Graham and Hank spent their time lying under the wing of the plane waiting for the next flight too. The wolves, however, were much more active.
At 11:30, the second flight of the day, Graham and Hank were back overhead: “Got a lot of wolf movement since this morning. There may be a boundary skirmish going on. Foys 2 and 4 have moved seven and a half kilometres northeast and are less than one kilometre from where Grand 3 was this morning. Grand 3 has cleared out and gone four and a half kilometres southwest, even farther into Foys territory. Basin 3 has moved two kilometres southeast. Foys 3 is near you, just south of the logging area where she was earlier. Foys 1 is up between the Spectacle lakes on the northeast corner of the territory. See you in four hours.”
Back in August 1988, Graham and assistant Harry Vogel caught the first two Foys Lake wolves, both big males, not far from the lake whose name Graham bestowed on the pack. Then in May 1989, Graham and Lee caught the next two Foys wolves. In late August 1989, Mary and I caught the fifth wolf, initially called Basin 3 but later Basin 3 Foys, destined to become one of the most valuable wolves of our study. The Basin Depot pack lived immediately east of the Foys Lake pack. Basin 3 Foys was a medium-large, young adult and looked out of a dark face at us from a pile of logs where the trap-hook caught. While collaring her, we noticed that her right hind leg was deformed, and remarked that this wolf would not give us much data. Her tibia-fibula bone, the normally straight “shin bone,” was curved like a bow. We could feel no break, nor was there any external lesion. We photographed the leg and recorded it as a birth abnormality, an interpretation later confirmed by X-ray on her dead body.
Mid-afternoon flight, drone of the airplane again. Mary and I roused ourselves from the shade.
“Less movement this time. Basin 3 — same place. Foys 1 — same place. They are eight kilometres apart. Grand 3 — same place. Foys 4 has moved over near Foys 1, about one and a half kilometres apart. Foys 3 has left the logging cut and moved three kilometres across the hydro line. He’s near the rendezvous site.”
In early December 1989, when the first winter snows sifted among the pines, Graham looked down on eleven Foys wolves walking on the ice of a marsh and three trespassing Basin wolves only two kilometres away. Two days later the packs were together.
That first record of amalgamated packs happened on a piercingly cold day that stripped the sunlight of any vestige of warmth. We drove up a narrow logging road, alert for loaded trucks, and parked in a log landing beside other pickups. From the top of a log pile, Mary picked up the signals of Basin 3 Foys and Foys 2, distant but both on the same bearing.
We packed our carcass kit and started up the skid trail, every few minutes scrambling into the trees while red skidders pulling logs churned by. A group of loggers invited us to stand by their fire, where we chatted about the abundant deer tracks and stayed off the topic of wolves.
The snow was at the awkward depth: too shallow for snowshoes but too deep for easy walking. We made our way down a long two-kilometre ridge and emerged at the McDonald Creek marshes. The signals were still ahead, coming from a spruce- and fir-covered point. Waiting, watching, we spotted a pair of ravens fly by, reach the point, then swerve and drop into the trees. Ravens only do that for a reason.
The wolves had been feeding on a big ten-point buck, having caught it under the shoreline cedars. Most of the meat and entrails had been consumed. According to our reading of the tracks, they jumped the deer and brought it down in only fifteen metres. Its frozen rumen lay nearby, pulled out of the body cavity after the deer had frozen; otherwise, wolf teeth would have ruptured it. Freezing would not have taken long in the −30°C temperatures of the previous night. Often an indication of scavenging, this time it was not, because the bone marrow was creamy with fat.
We chopped off the lower jaw and femur while the pack waited nearby. Long shards of sunlight slanted through the cedars. After we retraced our tracks to the truck, we drove back to Achray.
Two days later we returned to further document this rare amalgamation of packs. It was a Saturday, so the loggers were not at work. Wolf tracks plastered the road. We picked up the signals of the same two wolves as well as Foys 1. The wolves were close when we left the truck, but they moved ahead of us all day. Snow down our necks, near-frozen fingers on the radio dial, glasses steamed up, thick young stands of balsam fir in the way, unseen deadfall — it was a demanding hike. Tracking the wolves to the head of a stream we came to a dead-end canyon where their weak signals deflected from all directions. We climbed up through hardwoods, and as we crested a ridge, the signals suddenly became loud.
Through the conifers we could see the snowy opening of a hilltop bog. We edged closer until it was in full view. A wolf walked out of the trees onto the ice, then another, and a third that sat down. Then out came Basin 3 Foys, closely followed by the two big, collared males and a smaller wolf. Seven wolves, unaware of us, ambled across the bog and into the leatherleaf on the far side.
A few days later, Graham recorded seven tracks from the air where the pac
k fanned out across a lake. Basin 3 Foys was not among them. Two days after Christmas, he counted fourteen tracks with all three collared wolves present. For the rest of the winter they remained together, their territory covering the combined summer territories of the Basin Depot and Foys Lake packs.
At first we were not sure how to interpret this unusual pack fusion. Both packs had produced pups the previous summer. But then when the two packs stayed together the following summer, and continued to use the combined land of both packs, we realized that in the previous year there must have been two breeding females in just the one pack. Most wolf studies document a low occurrence of multiple litters.
Evening flight, Graham on the radio overhead: “Grand 3 is still living dangerously. She has moved two kilometres to Aurora Lake, even farther into Foys territory. She is almost where Foys 2 and 4 were this morning. Foys 1, 2, and 4 are all close to one another up at the McDonald Creek marshes six kilometres from her. They must have found each other out there. They didn’t have time to return to the rendezvous site and meet there. You should be getting both Basin 3 Foys and Foys 3. They’re in the rendezvous site.”
Clouds were drifting in, heralding a change in the weather. We monitored the signals from our tent. Basin 3 Foys came home at 7:30 P.M. after being away thirty hours. Fifty-five minutes later, Foys 3 returned after an absence of at least fifty-one hours, but he had always been close by and may have come in briefly when we were not there.
The storm hit just before midnight, booming in from the west, illuminating the sky and making the electricity in the hydro wires crackle. No other collared wolves returned. Between 3:05 and 4:50 A.M., Basin 3 Foys left the rendezvous site. By then the storm had faded to a distant rumbling. Foys 3 left too, just as the first strands of daylight were illuminating a wrung-out sky.
As the morning advanced, the clouds stayed draped over the hills, too low for a flight. We sat in the door of the tent and caught up on our notes. A doe came into the clearing and picked nervously at some aspen stems, glancing up every few seconds. Being so near the hub of wolf activity, she was not strategically well placed for a long life.