Nest predation and numbers of Golden PloversPluvialis apricariaand other moorland waders

Abstract

The recovery of a declining population of Golden Plovers may have been prevented by high nest predation from Carrion Crows Corvus corone and Common Gulls Larus canus. In order to test this hypothesis predators were experimentally removed from Kerloch moor in NE Scotland during 1986–89. Although the numbers of crows and gulls were significantly reduced, no young Golden Plover hatched at Kerloch and breeding numbers continued to decline. Numbers also declined on a less intensive study area 50 km further away where predators were not removed and where hatching success was poor (except in 1986). Hatching success of other moorland waders was generally higher during the experiment than before it, but breeding numbers did not increase. The removal of crows and gulls did not lead to increases in the breeding populations of Golden Plovers and other waders, although the outcome of the experiment was complicated by rising nest predation from foxes Vulpes vulpes whic¸ may have masked any benefits from the removal of other predators.