Birds stay put in Europe's warm weather

PARIS — Birds are delaying their annual winter migration to Africa from France because of the unseasonably warm weather, a French bird-protection group said on Thursday.

From Ottawa to Moscow, temperatures generally have been way above average at the start of winter in the Northern Hemisphere, with flowers blooming on snow-starved slopes of Alpine ski resorts and bears struggling to hibernate.

The autumn was the warmest in France since 1950, with temperatures five degrees above seasonal norms, the national weather agency has said.

"Long-distance migratory birds — those that spend the winter in tropical Africa — seem to be particularly late in leaving this autumn," the League for the Protection of Birds said in a statement.

The league's network of birdwatchers have spotted swallows all over France, including in the north, as well as warblers, which usually leave in August or September.

"This phenomenon is just another sign that we are seeing rapid and major climate changes that the birds are having to face, especially the migrators," it said.

It is warmer in Europe's Alpine region now than at any time in the past 1,300 years, said Reinhard Boehm, chief climatologist at Austria's Central Institute for Meteorology and Geo-Dynamics in Vienna.

Boehm based his comments on the results of a project conducted by a group of European institutes between March 2003 and August 2006. Their aim was to reconstruct the climate in the region encompassing the Rhone Valley in France to the west; Budapest, Hungary, to the east; Tuscany, Italy, to the south; and Nuremberg, Germany, to the north over the past 1,000 years.

Boehm said the current warm period in the Alpine region began in the 1980s, noting that a similar warming occurred in the 10th and 12th centuries. However, the temperatures during those phases were "slightly under the temperatures we've experienced over the past 20 years."

Humans first had an impact on the global climate in the 1950s, Boehm said, noting that, at first, the release of aerosols into the atmosphere cooled the climate. Since the 1980s, however, greenhouse gases such as carbon dioxide and methane have warmed it up, he said.

Many scientists say a single warm winter is most likely part of the natural variations of an unpredictable climate. Still, years of mild temperatures fit predictions of global warming, widely blamed on human use of fossil fuels.

Like many places, Austria had its mildest autumn since records began and many ski resorts have delayed the season's kickoff, shrinking the billion-dollar winter business.

From Siberia to Estonia, bears have had trouble going to sleep for their winter hibernation because their hideaways are uncomfortably warm, soggy and damp.