Declines of ground-nesting birds in two areas of upland farmland in the south Pennines of England

Abstract

CapsuleWe present evidence of large declines in numbers of breeding waders and passerines in some upland areas since the 1970s. Aims Changes in numbers of ground-nesting birds are documented for two areas of the Pennines and are qualitatively related to recent land-use history. Methods Territory mapping was used to estimate bird numbers on two areas (76 and 99 ha) in the Pennines for which more than 10 consecutive years of data were available from the BTO's Common Birds Census archives. Results At both sites there were large declines in Lapwing Vanellus vanellus, Snipe Gallinago gallinago, Skylark Alauda arvensis, Twite Carduelis flavirostris and Reed Bunting Emberiza schoeniclus. The two sites differed in the timing of the declines but for Twite the trends were almost identical. By the late 1990s, numbers of most ground-nesting birds were far lower than in the 1970s. There was relatively little change in numbers of species breeding at either site. Conclusions Progressive changes in land-use, involving loss of rough grassland and a switch from dairy to sheep farming, may have contributed to the declines at one of the sites. However, there was no obvious change in land-use or habitat loss at the other site where population declines began 5 to 10 years earlier. Such declines have probably occurred widely in moorland-edge areas during the last 30 years and multiple factors may be responsible.