By John Hassell
The diminutive Arctic fox, easily distinguished from other fox species by its snow-white fur in winter, appears to be yet another casualty of the ecological changes brought on by global warming. The International Union for Conservation of Nature (IUCN) has identified the Arctic fox as one of 10 species that are highly vulnerable to changes in temperature arising from climate change, thus turning the spotlight on the animal’s few remaining refuges, which include northern Ontario.
The report “should act as a wake-up call to governments,” says co-author, Wendy Foden, an IUCN climate change program officer, “to make real commitments to cut carbon dioxide emissions if we are to avoid a drastically changed natural world.” The climate change flagship species were selected to represent the impact that climate change is likely to have on terrestrial and aquatic ecosystems and therefore on wildlife.
In the case of the Arctic fox, warmer temperatures cause a reduction in the animal’s already circumscribed range, as the species depends on long, cold winters and is unable to adapt to environments other than its native tundra habitat. In Ontario, the range of the Arctic fox is mostly limited to a narrow strip along Hudson Bay on the province’s northern border. At the same time, the range of the red fox, which preys on Arctic fox kits and adults, is expanding. A superior hunter, the red fox can out-compete the Arctic fox for traditional prey, such as lemmings and voles, populations of which are already in decline due to milder and shorter winters.
“The Arctic fox is a specialist, highly adapted to the harsh conditions of the tundra,” says Mark Carabetta, manager of conservation and science at Ontario Nature. “As climate change causes profound ecological changes to the tundra, the Arctic fox will suffer, as will other highly adapted Arctic species.”
Five of the 10 climate change flagship species live in Canada, the other four being the salmon, leatherback turtle, beluga whale and ringed seal. The enormous strain that climate change places on northern ecosystems is of increasing concern as we begin the International Year of Biodiversity, which recognizes the severe diminishment of biological diversity in the natural world. That Canada contains half the wildlife highlighted by the IUCN should come as no surprise, given that only two of the 29 OECD (Organisation for Economic Co-operation and Development) countries have higher per capita energy usage rates. According to the International Energy Agency and the World Health Organization, in 2001 the average energy use by Canadians is 7,929 kilograms of oil equivalent per capita, which vastly exceeded the world average of 1,630 kilograms of oil equivalent per capita. Canada is also well shy of its pledge to reduce greenhouse gas emissions by 6 percent below 1990 levels by 2012.
The IUCN report further warns that approximately 20 to 30 percent of plant and animal species will be at increasingly high risk of extinction as global mean temperatures rise by 2 to 3 C. It is believed that climate change will be one of the major drivers of species extinctions in the 21st century, and global warming has already been implicated in hundreds of documented cases of species declines across marine, terrestrial and freshwater ecosystems around the world.