Ten Percent of Bird Species to Disappear, Study Concludes
WASHINGTON Ten percent of all bird species are set to disappear by the end of this century -- and with them the services they provide such as cleaning up carcasses and spreading seeds, U.S. researchers said Monday.
A careful study of extinction rates so far, conservation measures underway and climate and environmental change shows that at least 1,200 species of birds will be gone by 2100. And that is a conservative estimate, the team at Stanford University in California said.
"Even though only 1.3 percent of bird species have gone extinct since 1500, the global number of individual birds is estimated to have experienced a 20 percent to 25 percent reduction during the same period," they wrote in their report, published in the Proceedings of National Academy of Sciences.
This can have severe consequence for people.
"In 1997, 30,000 of the world's 35,000 to 50,000 rabies deaths took place in India, where feral dog and rat populations have exploded after the decline of vultures," they wrote.
Cagan Sekercioglu of the Stanford Center for Conservation Biology and colleagues analyzed all 9,787 living and 129 extinct bird species.
They examined conservation efforts, bird distribution, their ecological functions and life histories.
"The result is one of the most comprehensive databases of a class of organisms ever compiled," Sekercioglu said.
They then ran three scenarios in a computer program designed to forecast population changes -- one really bad, one moderately severe and one that presumed conservation measures would be enough to save any more birds from becoming endangered but not enough to stop the already threatened species from going extinct.
"Our projections indicate that, by 2100, up to 14 percent of all bird species may be extinct and that as many as one out of four may be functionally extinct -- that is, critically endangered or extinct in the wild," said Sekercioglu.
"These assumptions are conservative, since it is estimated that, every year, natural habitats and dependent vertebrate populations decrease by an average of 1.1 percent," the team wrote.
"Important ecosystem processes, particularly decomposition, pollination and seed dispersal, will likely decline as a result."
In November the World Conservation Union reported that it found 12 percent of all bird species were threatened with extinction, along with nearly one-fourth of the world's mammals, a third of amphibians and 42 percent of all turtles and tortoises.