Few places remain where wolves can live as nature intended (Image: Layne Kennedy/Corbis)
GORDON HABER was tracking a wolf pack he had known for over 40 years when his plane crashed on a remote stretch of the Toklat river in Denali national park, Alaska, last October. The fatal accident silenced one of the most outspoken and controversial advocates for wolf protection. Haber, an independent biologist, had spent a lifetime studying the behaviour and ecology of wolves and his passion for the animals was obvious. "I am still in awe of what I see out there," he wrote on his website. "Wolves enliven the northern mountains, forests, and tundra like no other creature, helping to enrich our stay on the planet simply by their presence as other highly advanced societies in our midst."
His opposition to hunting was equally intense. He excoriated the "heavy government-sanctioned killing" and "Mengele-like experiments" with wolf sterilisation in Alaska, which, as he saw it, threaten to transform the very nature of the wolf. And he did not pull his punches when identifying the enemy. "Perhaps worst of all, these problems originate primarily from biologists," he wrote on his website, referring to the fact that many wildlife managers work on the assumption that wolves can withstand heavy culling because they breed quickly.
In Alaska, up to 50 per cent of wolves are shot or trapped every year, with little effect on their numbers. But Haber argued that by focusing on population size, the establishment has ignored the fact that the hunting of wolves warps their social structure, ripping apart the family ties and traditions that define wolf society.
"Gordon was an aggressive personality, and he took on the scientific dogma about wolves," says Douglas Smith, leader of the Yellowstone Wolf Project. Despite many thousands of hours spent in the field, Haber published little peer-reviewed documentation of his work. Now, however, in the months following his sudden death, Smith and other wolf biologists have reported findings that support some of Haber's ideas.
Once upon a time, folklore shaped our thinking about wolves. It is only in the past two decades that biologists have started to build a clearer picture of wolf ecology (see "Beyond myth and legend"). Instead of seeing rogue man-eaters and savage packs, we now understand that wolves have evolved to live in extended family groups that include a breeding pair - typically two strong, experienced individuals - along with several generations of their offspring.
Building on this insight, Haber argued that older wolves pass knowledge down to younger pack members, and that human hunting disrupts this natural order. Lone survivors or pairs without supporting family members behave more unpredictably and kill more large prey animals than wolves living in stable packs, so hunting is often a counterproductive way of trying to manage wolf populations. His claims have been difficult to prove, partly because few corners of the Earth hold undisturbed wolf habitat where they can be tested.
Yellowstone National Park, located primarily in Wyoming and also in parts of Idaho and Montana, is one of the exceptions. Grey wolves were reintroduced here in 1995, following a 70-year absence that resulted from intense predator control measures in the early 20th century. The population now thrives, and in recent years it has become clear that packs there are different from those in areas where wolves are regularly killed because of conflicts with people or their livestock. Outside the protective boundaries of the park, few wolves live more than three or four years, and a pack seldom includes more than five or six individuals. Within Yellowstone, wolves tend to live longer - some have survived to be more than 10 years old - and they sometimes stick with their natal pack into their fourth or fifth year, a phenomenon never before recorded. As a result, packs are multigenerational and typically include about 11 wolves, though the biggest have more than 20 (Reintroduction of Top-order Predators, edited by Matt W. Hayward and Michael Somers, Wiley-Blackwell, 2009).
"Such packs do things very differently than the much simpler packs found in human-dominated landscapes," says Smith. When it comes to hunting, for example, there is a division of labour between the sexes. The fleeter females test herds of elk by rushing them at high speed, to find the weakest targets. Then the heftier males attack and kill the prey. Such skills clearly require practice: during a decade of intense wolf-watching, Smith and his colleagues have documented a learning curve among young wolves (Ecology Letters, vol 12, p 1). Yearlings are already at 80 per cent of full size, but the ability to take down an elk peaks at age 2, while the ability to choose the right elk to go after - the greatest intellectual challenge for wolves on the hunt - doesn't peak until age 3. Smith believes hunting skills are learned by watching older pack members, and from experience.
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