SALT LAKE CITY, March 5 (UPI) -- U.S. scientists say as many as 900 species of tropical birds could be extinct by 2100 due to global warming as each degree rise could affect 100 to 500 species.
Researchers writing in the Biological Conservation Journal say the finding assumes a rise in Earth surface temperatures of 6 degrees F by the end of the century.
Mountain, coastal, restricted-range species and species unable to get to higher elevations could be the worst affected, researcher Cagan Sekercioglu, professor of biology at the University of Utah, told the BBC.
Topical mountain species are among the most vulnerable, he said, as forests could recede higher up mountains with global warming and forest habitat suitable for many species could "get pushed off the mountain."
This result would be "an escalator to extinction," he said.
"This gives us a clear big picture," he said. "The problem is most species in the world are highly sedentary ... the public perception is most birds are migratory and so climate change is not a problem for them," he said.
"We need to be planning protected areas with higher elevations in mind and leave breathing room for endangered species in higher elevation areas."