NEW HAVEN, Conn., June 11 (UPI) -- U.S. biologists say they've determined the extinction risk for mountain birds due to global warming is greatest for species occupying a narrow altitude range.
Yale University researchers said they found a species' vertical distribution is a better predictor of extinction risk than the extent of temperature change they experience.
"Birds allow us to do the first global assessment of the health of a whole large chunk of biodiversity at high altitudes in the face of global warming," said Professor Walter Jetz and postdoctoral researcher Frank La Sorte, the study's co-authors. "Our global projections pinpoint hundreds of bird species in peril and often with nowhere to go."
La Sorte and Jetz said they estimated the vulnerability of mountain species to climate change by looking at a variety of factors, including the birds' ability to move to higher and cooler elevations or to neighboring mountain systems.
The team studied all 1,000 species of birds living in high-elevation environments and found a third of all mountain bird species are severely threatened.
The study highlights Africa, Australia, and North America as regions of particular concern because dispersal opportunities are the most limited.
The findings appear in the Proceedings of the Royal Society B: Biological Sciences.