| WASHINGTON
- February 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 http://www.worldwildlife.org
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