Feeling the heat

2003-01-03 15:45

Washington - Global warming is impacting the natural world by forcing animal and plant species worldwide to shift habitats, according to two major US biology studies published on Thursday.

Species are shifting toward the poles and up mountains, say the studies, to adjust to rising temperatures that the Intergovernmental Panel on Climate Change blames on man-made emissions.

While European insects and mammals have moved north, for example, flowers have bloomed, and birds have laid eggs, earlier in the year, said the two 'meta-studies' published in the journal Nature.

The trend is playing havoc with delicate ecosystems as interdependent species move apart at separate speeds, and they warn the problem will worsen if the temperature shift gains speed.

The march toward the poles has averaged 6.1km a decade, while spring events such as egg-laying have moved forward by an average of 2.3 days a decade, said a Texas University study.

Stanford University and other scientists also found "a consistent temperature-related shift, or 'fingerprint', in species ranging from molluscs to mammals, and from grasses to trees".

The multiple onslaught of rising temperatures, habitat destruction and other stresses, it warned, "could easily disrupt the connectedness among species" and drive some of them to extinction.

"You're seeing the impact of climate on natural systems now," a co-author, Wesleyan University economist Doctor Gary Yohe, told the Times. "It's really important to take that seriously."

While species have adjusted to gradual climate shifts in the past, the researchers warn, this change is more dangerous because wilderness areas have been fragmented by human infrastructure.

"The pre-industrial migrations were made without having to worry about cornfields, parking lots and Interstates," Pennsylvania State University's Doctor Richard Alley, an expert who was not involved in the two studies, told The New York Times. - Sapa-DPA

- SAPA