The decline of Black Grouse in Scotland and northern England.

Abstract

Analysis of shooting bag records suggest a 90-93% decrease in numbers of Black Grouse shot in Scotland and northern England since 1900. The magnitude of the decline differed between regions; the most severe declines were found in western Scotland, where the highest numbers of birds were once shot, but where fewest are shot today. By contrast, numbers shot in eastern Scotland (Perthshire and Angus) have declined relatively little and this region is currently the stronghold for Black Grouse in Britain. Overall, numbers shot in Scotland and northern England have changed little over the last 40 years, but as only 25% of estates now shoot Black Grouse, shooting bags may no longer provide an accurate index of population trends.
Responses from a questionnaire survey and from spring counts of males attending leks support the decline trends inferred from shooting records, with fewer estates in western Scotland having Black Grouse, and those that had reporting declining populations more frequently and male densities fourfold lower than in parts of eastern Scotland. The current British population was estimated at a little over 25,000 displaying males in spring.