A major survey is being launched to try and halt a catastrophic decline in the population of wading birds in lowlands like the Aire Valley.

The Royal Society for the Protection of Birds and the Yorkshire Dales National Park is to investigate the number of breeding waders in the national park.

The survey - to start in April - comes amid concern that recent population studies have shown a major decline across the UK.

Upland areas, like the Yorkshire Dales, are regarded as vitally important breeding areas for waders, including snipe and redshank.

A survey has revealed that between 1972 and 1996, the population of lapwings slumped by 46 per cent and snipe by up to 95 per cent in lowland areas.

Alistair Crowle, RSPB conservation officer, said: "We are witnessing near catastrophic declines in lowland wader populations.

"With waders now concentrated in the uplands, it is vital we get a clear picture on the health of those populations if we are to secure a future for waders in the UK."

Ian Court, species officer of the YDNP, said: "Upland areas of the UK, like the Yorkshire Dales, are becoming crucial breeding areas for many species of wader."

Survey sites will be visited three times between April 17 and June 19 during the first three hours after dawn and before dusk. All landowners will be contacted for permission before the survey starts.

The probe will cover an area of up to 100 square kilometres of moorland edge pasture and meadowland.

In a separate study, the RSPB is re-surveying some upland bird study plots this summer and seeking permission from landowners to get onto the sites.

The post of species officer at the Yorkshire Dales National Park is jointly funded by English Nature, the Royal Society for the Protection of Birds and the Yorkshire Dales National Park.

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