A group of new studies find that the patterns of bird migration literally change with the weather — or more accurately, the climate.
Boston University scientists have been analyzing the timing of migrations of 32 species of birds since 1970, Thainidian News reports.
They found that birds’ earlier spring arrivals on the East Coast owed to warming temperatures.
The swamp sparrow, which overwinters in the American south, has kept pace with climate change because it doesn’t have to travel as far for food as temperatures shift.
The great crested flycaster, however, travels as far as South America, and can’t adapt as easily to the changing availability of food.
The Times of India reports that a scientist at Britain’s Durham University has reached a similar conclusion about bird migration in Europe.
Professor Brian Huntley discovered a prevalence of species normally found in southern Europe — such as the Dartford warbler, Cirl bunting, little egret and Cetti’s warbler — have become more common in the northern part of the Continent over the last 25 years.
Huntley also found that species native to the north — such as the fieldfare, redwing and Slavonian grebe — have become rarer.
Climate change has also apparently driven Magellanic penguins from Argentina and Chile to Brazilian shores earlier than usual — and many are not arriving healthy.
As reported in The Guardian, an Argentine biologist theorizes that the penguins can’t find enough food in their habitat.
“One reason could be that warming waters and climate change have impacted the fish population,” Marcelo Bertelotti told the newspaper.
Other scientists also blame a recent oil spill off the Uruguayan coast has despoiled the penguins’ feeding waters.
Stanford University conservation expert Cagan H. Sekercioglu said the search for cooler climes could lead to an “escalator to extinction” for 15 percent of the world’s 10,000 species of birds by the end of the 21st century.
“Over half of seabird species are already threatened or near threatened with extinction,” he told ecological advocacy Web site Mongabay.com. “This is double the rate of forest birds.”
–T.J. Johnston/Newsdesk.org
Sources:
“As climate warms, birds are migrating earlier: study”
Thaindian News, June 22, 2008
“Birds fly north in climate change vanguard”
Times of India, July 30, 2008
“Penguins wash ashore in Brazil, prompting concerns about their habitat”
The Guardian, July 23, 2008
“Birds face higher risk of extinction than conventionally thought”
Mongabay.com, July 15, 2008
This theory is really interesting….!!!!