CLIMATE change is having a serious effect on birds, ranging from garden species to winter waders in Poole Harbour.

Garden birds are laying their eggs a week earlier than 40 years ago and some winter wader numbers are decreasing dramatically, according to the latest State of the UK's Birds report.

"This year's report shows that climate change is with us already and from our gardens to our seas, birds are having to respond rapidly simply to survive," said Dr Mark Avery, RSPB conservation director.

"As often before, birds are acting like the canaries in a mine shaft and giving us early warning of dangerous change."

The 2007 report shows that nationwide chaffinches are on average laying their eggs a week earlier than 40 years ago. Similar species such as blue and great tits, robins and swallows are equally affected.

In 1966 the average date for chaffinches laying their first egg was May 11 but this had moved to May 2 by 2006.

For robins average dates jumped from April 28 to April 22.

The changes in laying dates are believed to be in response to increasing temperatures triggered by climate change, according to the report produced by the RSPB, British Trust for Ornithology, Wildfowl and Wetlands Trust and nature conservation agencies.

It also highlights that numbers of winter visiting wading birds, for which Poole Harbour is a site of international importance, are decreasing.

During the 1990s numbers were rising but species, including purple sandpipers, ringed plovers and dunlin have dropped by more than 59 per cent, 13 pc and 21 pc respectively between 1979/90 and 2004/5.

The decline is thought to be largely due to birds wintering elsewhere in Europe where conditions are becoming more suitable.

The dunlin used to be the UK's most numerous wading bird in winter but it is now at its lowest level since records began.