Recent Report Shows Global Warming Could Be Final Straw for Wolverines
Habitat Fragmentation and Loss, Human Disruption and Trapping are Main Threats to Wolverine Survival
(03/12/2007) - Washington, D.C. -- Wolverines face an uncertain future due to global warming and other threats from humans, a new report by Defenders of Wildlife concluded today. The report shows that global warming and human activity are shrinking and fragmenting this rare carnivore's habitat, which when compounded by trapping and other threats, could push the wolverine toward local and regional extinction. The report is the third chapter in Defenders of Wildlife's global warming series titled "Navigating the Arctic Meltdown.""Global warming is one of the gravest threats facing wildlife today, and animals like the wolverine are in real danger of falling victim because their habitat is changing too rapidly for them to keep up," says Rodger Schlickeisen, president of Defenders of Wildlife. "We are seeing this especially in the Arctic, but global warming is also affecting the wolverine's mountainous habitat much further south."
According to the report, global warming is robbing wolverines of suitable habitat and denning areas from the Arctic all the way to the U.S. and Canadian Rockies. Recent research has found that snow lines are likely to climb 300 feet higher for every degree the temperature rises, thus reducing habitat that is necessary for wolverine survival. In addition, snow seasons are expected to shorten by nearly two months in the coming decades. This severe change is resulting in less snow pack, which appears to be detrimental to denning mothers and their kits. The female wolverine creates a burrow deep under the insulating snow to provide shelter and protection for her kits. Shortened winters and reduced spring snow pack shrink available denning habitat and reduce the chances that kits will survive. Milder winters also mean lower natural mortality in elk and deer, whose carcasses are the wolverine's most important food source in winter.
"Wolverines thrive in areas where the ground is snow-covered throughout the winter and seek higher, cooler elevations during the summer months, but it is getting much harder for wolverines to find this type of habitat because of changes brought on by global warming," says Chris Haney, chief scientist for Defenders of Wildlife.
Roads and development are also a detriment to the wolverine's survival. They are naturally solitary animals that establish large home ranges due to the scarcity of food in their often inhospitable homes. In fact, one study in Arctic Canada found that the home range of a female wolverine is about 50 square miles, and the male wolverine claims about 150 square miles for himself. Roads in the Rockies appear to have separated these loners into smaller subpopulations that might not be able to sustain themselves over many generations.
Trapping and other forms of recreation are also significant threats to wolverines. Even those outdoor activities that are seemingly harmless can devastate wolverine habitat. Wolverines are extremely sensitive to human disturbance, so simply skiing or snowshoeing near a den while a female is rearing her kits can cause the mother wolverine to abandon the den and move her kits to a more suitable location.
The report asserts that in order to preserve wolverines and other species that live high in the mountains, the U.S. should first attack the problem at its core and reduce the emission of carbon dioxide and other greenhouse gasses.
"Our ongoing efforts to protect wolverines and other animals and plants will only succeed if Congress acts now to reduce emissions that contribute to global warming. But until the environment shows signs of recovery, there are additional important steps we can take to preserve wolverine populations," says Schlickeisen.
"The most proactive measure we can take to save the wolverine is to protect its habitat in the U.S. and Canadian Rocky Mountains and Arctic wilderness areas," says Haney. "We can protect large swaths of roadless habitat and control human access for recreation or development in the high mountain basins where wolverines are likely to be denning."
According to this latest chapter in Defenders' "Navigating the Arctic Meltdown" series, necessary measures include controlling trapping and reducing motorized recreation, especially helicopter skiing and snowmobiling, in those isolated mountain basins that are prime denning habitat for the wolverine. Future industrial development, such as oil and gas drilling, logging and mining, should also be restricted in large protected areas, since these areas serve as sources for wolverine habitat and dispersal into other regions. Also, corridors for wolverine movement should be restored where valleys between mountainous areas are criss-crossed by roadways. And more research on this elusive and poorly understood carnivore is urgently needed, so that the design and placement of these corridors provide maximum benefit for wolverines.
"While it may take up to 100 years to fully reverse the harm we've already done to the Earth's climate, it is our responsibility to step up our efforts to preserve wildlife that is being affected by global warming today so they are around tomorrow," concludes Schlickeisen.
Wolverines could get a rare helping hand from the federal government. In 2000, Defenders of Wildlife and other groups petitioned the U.S. Fish and Wildlife Service to protect wolverines in the lower 48 states under the Endangered Species Act. In 2003, the Bush administration denied the petition, citing insufficient evidence of declines. Defenders successfully challenged that decision in court, and the government is now reconsidering listing the wolverine.
The first three chapters of "Navigating the Arctic Meltdown" and subsequent installments as they become available can be found at www.defenders.org/globalwarming.
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Defenders of Wildlife is recognized as one of the nation's most progressive advocates for wildlife and its habitat. With more than 500,000 members and supporters, Defenders of Wildlife is an effective leader on endangered species issues.
Contact(s):
Joe Vickless, (202) 772-0237Chris Haney, (202) 772-0292
