Black grouse national surveys

The male black grouse <I>Tetrao tetrix</I> population in Britain was surveyed in 1995/96 and 2005, in order to estimate population size. <br /><br />The surveys were based on counts of males displaying in the spring. In Wales and Staffordshire, the entire known population was surveyed in 1995. In northern England and Scotland in 1995/96 and 2005, and in Wales in 2005, a stratified random sample of 5 km squares from the breeding range was surveyed. As such the dataset covers around 10% of the UK population overall and does NOT contain all black grouse leks in Britain in the survey years; its aim was to produce a reliable population estimate. <br /><br />The 5 km squares where no black grouse were found will be included in the dataset when zero record display becomes available on the NBN. <br /><br />The 1995/96 survey estimated a population of 6510 males, the 2005 survey estimated population size to be 5078 males, a non-significant 22% decrease.<br /><br />
The surveys were organised by the Statutory Conservation Agencies and RSPB Breeding Bird Surveys (SCARABBS) scheme. The 1995/96 survey was funded by the RSPB, Scottish Natural Heritage, English Nature (now Natural England), the Joint Nature Conservation Committee and the Game Conservancy Trust (now the Game and Wildlife Conservation Trust). The Perthshire Black Grouse Study Group carried out a substantial part of the fieldwork. The 2005 survey was funded by the RSPB, the Countryside Council for Wales, Forestry Commission Scotland, the Game Conservancy Trust (now the Game and Wildlife Conservation Trust) and the Defra Rural Development Service (now part of Natural England), and organised with substantial help from the Central Scotland Black Grouse & Capercaillie Study Group, the Perthshire Black Grouse Study Group and the Strathspey Black Grouse Study Group.