Climate change threatens tropical birds

EurekAlert: Climate change spells trouble for many tropical birds – especially those living in mountains, coastal forests and relatively small areas – and the damage will be compounded by other threats like habitat loss, disease and competition among species.

That is among the conclusions of a review of nearly 200 scientific studies relevant to the topic. The review was scheduled for online publication this week in the journal Biological Conservation by Çağan Şekercioğlu (pronounced Cha-awn Shay-care-gee-oh-loo), an assistant professor of biology at the University of Utah.

There are roughly 10,000 bird species worldwide. About 87 percent spend at least some time in the tropics, but if migratory birds are excluded, about 6,100 bird species live only in the tropics, Şekercioğlu says. He points out that already, "12.5 percent of the world's 10,000 bird species are threatened with extinction" – listed as vulnerable, endangered or critically endangered by the International Union for Conservation of Nature (http://www.redlist.org).

Şekercioğlu's research indicates about 100 to 2,500 land bird species may go extinct due to climate change, depending on the severity of global warming and habitat loss due to development, and on the ability of birds to find new homes as rising temperatures push them poleward or to higher elevations. The most likely number of land bird extinctions, without additional conservation efforts, is 600 to 900 by the year 2100, Şekercioğlu says.

"Birds are perfect canaries in the coal mine – it's hard to avoid that metaphor – for showing the effects of global change on the world's ecosystems and the people who depend on those ecosystems," he adds.

...Scientists expect climate change to bring not only continued warming, but larger and-or more frequent extreme weather events such as droughts, heat waves, fires, cold spells and "once-in-a-century" storms and hurricanes. Birds may withstand an increase in temperature, yet extreme weather may wreck habitats or make foraging impossible....

A red-breasted toucan, shot by Dario Sanches, Wikimedia Commons via Flickr, under the Creative Commons Attribution-Share Alike 2.0 Generic license