
World Wildlife Fund: Disappearance of North American Mammal Linked to Global Warming; Photo Available 2/25/2003
From: Kathleen Sullivan of the World Wildlife Fund, 202-778-9576; e-mail: kathleen.sullivan@wwfus.org WASHINGTON, Feb. 24 -- New research published in the February 2003 issue of the Journal of Mammalogy indicates that American pikas may be one of the first mammals in North America known to fall victim to global warming. A smaller relative of rabbits and hares, American pikas (Ochotona princeps) have short, round ears and make their homes among the broken rocks or talus at high elevations in the mountains of the western United States and southwestern Canada. According to the new study, global warming appears to have contributed to local extinctions of American pika populations in the Great Basin area -- the area between the Sierra Nevada and Rocky Mountains -- during the latter part of the 20th century. If the global warming trend is not reversed soon through a significant reduction in emissions of CO2 and other heat-trapping gases, further population losses of the American pika may occur. "Losses of pikas are disturbing because they are often assumed to be locally abundant and, in decades past, scientists assumed that alpine and subalpine ecosystems were relatively undisturbed because of their isolation," said Dr. Erik Beever, an ecologist with the US Geological Survey's Forest and Rangeland Ecosystem Science Center and primary author of the study. "The responses of American pika populations are likely an early signal of the impacts of climate change in alpine and subalpine systems." Previous research results suggested that American pikas are particularly vulnerable to global warming because they reside in areas with cool, relatively moist climates like those normally found in their mountaintop habitat. As temperatures rise due to increasing emissions of CO2 and other heat-trapping gases, many montane animals are expected to seek higher elevations or migrate northward in an attempt to find suitable habitat. Living essentially on high-elevation islands means that American pikas in these regions have little option for refuge from the pressures of climate change because migration across low-elevation valleys represents an incalculably high risk -- and perhaps an impossibility under current climate regimes -- for them. Results from the new study suggest that climate may be interacting with other factors such as proximity to roads and smaller habitat area to increase extinction risk for pikas, creating detrimental synergistic effects. "American pikas may unfortunately be the 'canary in the coal mine' when it comes to the response of alpine and mountain systems to global warming," said Dr. Lara Hansen, senior scientist, World Wildlife Fund Climate Change Program. "Their disappearance is an indication that our heavy reliance on polluting fossil fuels is causing irreparable damage to our environment. We must make the switch to clean renewable energy resources like wind and solar now before it's too late." American pikas may act as 'ecosystem engineers' at talus margins because of their extensive haying activities. Since food is difficult to obtain in winter in the alpine environment, pikas cut, sun-dry, and later store vegetation for winter use in characteristic 'haypiles' above a rock in talus areas. --- Note to editors: High resolution photographs of American pikas are available to accompany press stories based on this research and mentioning WWF. If used, appropriate credit must also be given to the photographer. Journal of Mammalogy website: http://www.mammalsociety.org/pubjom/ World Wildlife Fund, known worldwide by its panda logo, leads international efforts to protect endangered species and their habitats and to conserve the diversity of life on Earth. Now in its fourth decade, WWF works in more than 100 countries around the globe. This news release and associated material can be found on www.worldwildlife.org ------ EDITOR'S NOTE: A high-resolution photo supporting this story is available for editorial use at: http://www.wirepix.com/newsphotos/USN |