Hundreds of Species Pressured by Global Warming
STANFORD, California, January 2, 2003 (ENS) - Hundreds of plant and animal species around the world are feeling the impacts of global warming, although the most dramatic effects may not be felt
for decades, according to new research from a Stanford University team. They predict that a rapid temperature rise, together with other environmental pressures, "could easily disrupt the connectedness among species" and lead to numerous extinctions.
"Birds are laying eggs earlier than usual, plants are flowering earlier and mammals are breaking hibernation sooner," said Terry Root, a senior fellow with Stanford University's Institute for International Studies (IIS) and lead author of the article published in today's issue of the journal "Nature."
Root and her colleagues analyzed 143 scientific studies involving a total of 1,473 species of animals and plants for the article, "Fingerprints of global warming on wild animals and plants."
After analyzing all 143 studies, the Stanford team concluded that global warming is having a statistically significant impact on animal and plant populations around the world.
As temperatures have increased, some species began breeding and migrating earlier. Other studies confirmed that species, from butterflies and marine invertebrates, have shifted their ranges northward as temperatures rose, occupying areas previously too cold for survival.
"Our study shows that recent temperature change has apparently already had a marked influence on many species," the Stanford team wrote.
In their analysis, Root and her co-workers showed that nearly 1,200 species, some 81 percent of the total number analyzed, have undergone biological changes that were "consistent with our understanding of how temperature change influences various traits of a variety of species and populations from around the globe."
Long term observations of flowering plants in Wisconsin show that wild geraniums, columbine and other species are blooming earlier than before.
Studies in Colorado found that marmots are ending their hibernations about three weeks sooner than they were in the late 1970s.
Measurements taken in Alaska revealed that growth in white spruce trees has been stunted in recent years - another expected consequence of a rapidly warming climate, Root said.
"Climate change models predict that the poles will warm more quickly than the equator, so it's not surprising that we're getting the strongest signals of biological change from Alaska and other northern regions," Root said.
A primary concern for wild species and their ecosystems is the rapid rate of change predicted during the next century.
She predicted that rapid climate change, coupled with the loss of habitat and other ecological stressors, could lead to the disappearance of species - a consequence that might be avoided by taking proactive instead of reactive conservation measures.
"For example, there's a very high probability that global warming could contribute to a 50 percent decline in breeding waterfowl populations," Root predicted.
"One thing we might do now is to consider adjusting the bag limits for hunters so we don't add insult to injury in the coming years," Root suggests. "Because anticipation of changes improves our capacity to manage, it behooves us to increase our understanding about the responses of plants and animals to a changing climate."
Co-authors of the study are Jeff Price of the American Bird Conservancy in Colorado, Kimberly Hall of Michigan State University, Stanford biology professor Stephen Schneider, Cynthia Rosenzweig of the NASA Goddard Institute for Space Studies, and Alan Pounds of the Golden Toad Laboratory for Conservation in Coast Rica.
The study was financially supported by the U.S. Environmental Protection Agency, the Winslow Foundation and the University of Michigan.