EARLY birds and night owls are being asked to help the RSPB with a survey of one the UK's rarest feathered creatures - the corncrake.

As part of the survey members of the public are being asked to listen for the distinctive call.

As the birds largely sing at dusk, through the night and very early in the morning, the RSPB is asking postmen, milkmen, newspaper deliverers, health visitors, farm workers and anyone who might be out and about at such hours to be especially alert.

Last year there were more than 670 recorded calling male corncrakes in the UK, the highest numbers since survey work started in 1978, but almost all of them were in Scotland.

Mark O'Brien, survey co-ordinator, said the once common bird suffered a severe drop in numbers due to changes in farming practices, but it might be making a comeback.

"Last year there were more than 670 calling males recorded, this year we hope to find more than 700," he said.

Last year a pair of corncrakes successfully nested at a secret location in the Yorkshire Dales.

May and June are the best months to listen for corncrakes, as the birds have just arrived from their winter quarters in Africa and are eager to set up territory and find a mate.

The male sings his rather monotonous song, which has a rasping, buzzing quality, and consists of two notes "crake-crake" repeated frequently.

Anyone who thinks they have heard a corncrake is asked to call the RSPB on 01767 680551. Details of date, time of day, place and habitat will all be needed to help confirm the record.

Updated: 10:08 Saturday, May 31, 2003