WASHINGTON - 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.
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.