CONSERVATIONISTS in East Anglia are worried about unusual wildlife behaviour which may be caused by climate change.Studies by the Suffolk Wildlife Trust following last year's long hot summer suggest that reptiles went into hibernation earlier than usual and there are now fears over survival rates.

CONSERVATIONISTS in East Anglia are worried about unusual wildlife behaviour which may be caused by climate change.

Studies by the Suffolk Wildlife Trust following last year's long hot summer suggest that reptiles went into hibernation earlier than usual and there are now fears over survival rates.

The dormouse - an endangered species - may also be suffering as a result of mild winters because it has to use up stored energy in order to keep its body temperature low enough to remain in hibernation.

Globally, the ten hottest years on record have occurred since 1991 and scientists believe that last summer's European heatwave, which is thought to have led to the deaths of more than 20,000 people, may be a taste of things to come.

Research published last week suggested that climate changed threatened extinction for a quarter of the world's species by 2050.

Climate change in Britain over the past ten years has brought both positive and negative impacts for wildlife.

Some birds and butterflies have begun to over-winter in this country instead of migrating to warmer climes.

Negative impacts include a boom in population of the brown rat, many of which were usually killed off by freezing conditions which often lasted several weeks at a time.

An analysis of monitoring work carried out by the Suffolk Wildlife Trust during the autumn suggests that reptiles such as common lizards and slow worms went into hibernation earlier than usual following the hot, dry summer.

"This is likely to have been because there was no food about but as cold blooded animals they also find it harder to regulate their own temperatures in hot weather, so they hide away," said Dr Simone Bullion, a conservation officer with the trust.

The concern is that the reptiles had not built up sufficient reserves in order to survive an extra-long hibernation.

Dr Bullion said the problem for dormice was quite different because there had been abundant food in the autumn - in the form of berries and nuts from hedgerows and trees.

"The problem here is that winters have become so mild that the dormice are using up more energy trying to keep their body temperatures low enough for hibernation.

"They are best adapted to having winter temperatures usually freezing or just above. But we're rarely seeing that any more. Higher temperatures mean that they use up their fat reserves more quickly and may wake up more often.

"The danger if the mild winter continues is that the creatures will emerge early from hibernation when there is no food around leading to starvation, or they may face a very cold spell," she said.

Dr Bullion said national studies suggested there could be a slow decline in dormouse numbers in East Anglia where populations are now confined largely to Essex and Suffolk.

"We've been monitoring populations here since the late 1990's and it is hard to tell if there is a decline and, if so, whether climate change may be a factor. If there is a decline it is an insidious one," she added.

The changing climate is also affecting birds' migration patterns, according to data released yesterday by the Thetford-based British Trust for Ornithology. Swallows were seen in many areas throughout December and there were two sightings of house martins in Suffolk on November 24.

"Climate change is the biggest environmental threat the world faces," Friends of the Earth said yesterday in a warning about sea-level rise.

"Unless urgent action is taken by everyone to reduce use of fossil fuels which produce carbon dioxide, the main global warming gas, the lives and livelihoods of millions people across the world will be under threat," said Tony Juniper, the group's director.