The wolverine, in the words of various protagonists in Doug Chadwick's "The Wolverine Way," is "badass," "the coolest of carnivores," "big heart and lungs and souped-up metabolism," and "a life support system for a set of legs." No one sums it up better than veterinarian Dan Savage: "There's tough, and then there's wolverine."
A 20- to 40-pound mass of muscle, teeth, and audacity, so fearless as to be willing to square off with grizzlies, and an occupant of some of the least hospitable environments one could imagine, the wolverine is also one of the rarest and least known animals in North America. Unfortunately, as Chadwick relates, the wolverine is in jeopardy because of rapid climate change, making the species the land equivalent of the polar bear.
Chadwick's book chronicles the ambitious work of the Glacier Wolverine Project (2002-2007), a study of wolverine distribution and population dynamics, including breeding success, survival rates, and dispersal to new habitats, which encompassed a range of 3,500 square miles. This five-year project in Glacier National Park (the Humane Society Wildlife Land Trust was a modest financial supporter) brought together scientists, veterinarians, wildlife officials, and others in an effort to apply the best of modern technologies to the study of this little known creature. Chadwick was a volunteer, dragging bait to lay scent trails, helping to construct log cabin traps, following tracks in snow and blizzard conditions, assisting with the implantation of GPS devices, and radio tracking Glacier's wolverine population.
Like other North American carnivores, wolverines were perennial victims of 20th century predator destruction policies, but they rebounded in the 1960s and 1970s as environmentalists succeeded in campaigns to limit the use of predator poisons. Wolverines got a foothold in Glacier National Park and the surrounding national forests, and eventually recolonized mountain chains in Montana, Idaho, and Wyoming. Currently, there are 40-50 wolverines in the 1,500 square miles of Glacier, making it the most significant concentration left in the contiguous states. Overall, there are somewhere between 100 and 150 in Montana, with a similar number in Idaho. Yellowstone and Grand Teton National parks may have another 50, with Washington's North Cascades holding a few more. No more than 400 individuals in the lower 48. Populations are larger in Alaska and Canada.
Among other achievements, the Glacier research overturned the longstanding view that wolverines are ferocious, antisocial animals, showing their family ties, cooperation, affection, and playful spirit. Researchers also confirmed the absolutely staggering distances these animals can cover even over the most rugged terrain.
Wolverines exist at low densities in big home ranges at the highest elevations of our continent, on terrain too high, cold, steep, and snowbound for other predators and scavengers to endure. Snow, ice, and cold are central to their denning habits, their comparative advantage in relation to other species, and their survival. That's why climate change is a looming threat to this species. Not only do warming temperatures leave less snow, but they are also contributing to a massive die-off of whitebark pine, a hardy, high-altitude tree whose logs are often incorporated into wolverine dens.
Since the early 1990s, environmental and animal protection groups have been pressing the U.S. Fish and Wildlife Service to list the wolverine as imperiled in the contiguous states under the Endangered Species Act, with the FWS twice concluding that not enough is known to warrant protection. In April 2010, in the aftermath of a lawsuit brought by Defenders of Wildlife, the FWS announced that it would undertake a status review, to consider the wolverine as a candidate for listing as a threatened or endangered species. The deadline is set for this December, and The Humane Society of the United States will press for a favorable decision.
There are other threats to wolverines. The most significant is that of wilderness that is shrinking and fragmented by development and highways, and by such recreational activities as heli-skiing, snowmobiling, cross-country ski touring and other pursuits that encroach on the narrow ribbon of timberline habitat available for wolverine denning.
Among other solutions, Chadwick advances the case for safeguarding habitats and adequate linkages between them -- particularly park-to-park wildland corridors that allow animal species to migrate, disperse, adapt, and maintain the genetic diversity that is ultimately essential to their survival. The concept has many champions, including Freedom to Roam, a program sponsored by Patagonia, which also published "The Wolverine Way."
From the humane perspective, it's worth noting Chadwick's concerns about the effects of trapping on the species. "The Wolverine Way" calls into question the propriety of Montana's trapping season on wolverines (admittedly small), and specifies the threat of the hundreds of thousands of traps set throughout the American backcountry for other midsized carnivores, traps that are capable of killing wolverines. Chadwick's proposals for a ban on trapping of midsize and large animals in and around reserves with wolverine populations, and the restriction of trapping in linkage zones between these areas, have real merit.
Like the wolverine itself, "The Wolverine Way" is a rare and admirable creation. Chadwick's engaging style, compelling voice, and hopeful attitude underscore what is at stake in the struggle, setting out an agenda for the wolverine's protection, and establishing the immeasurable worth of this citizen of the wild.
This post originally appeared on Pacelle's blog, A Humane Nation.