The society's researchers will now carry out further tests from feathers of slender-billed curlews held in museums.

BBC: Slender-billed curlew, WWW

The scheme should encourage wildlife such as lapwings, stone curlews and plants such as Devil's Bit Scabious and wild thyme.

BBC: Farming traditions revived at Stonehenge

The bodies of eight underweight stone curlews have been discovered in fields in Norfolk, Suffolk and Wiltshire over the past few days.

BBC: Stone curlews died underweight because of 'cold spring'