Seasons 'becoming muddled'

British autumn: It now lasts beyond October

British seasons are becoming increasingly muddled, say conservationists.

Spring was three weeks early this year and autumn is likely to be late.

The call of the first cuckoo was five days premature while autumn leaves should fall a week or so late.

The majority of climate scientists would agree that there are already signs of a warming climate

Dr Tim Sparks

The Woodland Trust says higher than average temperatures from January to April are to blame, and points the finger at climate change.

It will have serious consequences for animals, insects and trees, says the charity.

The study was carried out in collaboration with the Centre for Ecology and Hydrology (CEH) in Monks Wood, Cambridgeshire.

It is based on data gathered by 17,000 volunteers since 1998, and historical records spanning 50 years.

Leaf loggers

Dr Tim Sparks of the CEH said the most astonishing finding was how much earlier spring came in 2002 compared with 2001.

"The majority of climate scientists would agree that there are already signs of a warming climate and this is having a knock-on effect on our plants and animals," he told BBC News Online.

As well as plants flowering early in spring, autumn too is breaking with tradition.

Bluebells appeared early in 2002

Last year, autumn was at least a few days late.

Oak trees changed colour more than a week late, while beech trees lost their leaves 12 days later than usual.

Meanwhile, some people in the mildest parts of the UK had to mow their lawns all year round.

The Woodland Trust is calling for more volunteers to help monitor natural events this autumn.

People are being asked to record the departure of swifts and swallows, and leaf fall of native trees by logging on to www.phenology.org.uk.