Black grouse may be affected by increased human recreational disturbance. In England, the Countryside and Rights of Way (CRoW) Act became law in 2000, providing a statutory right of access to mountain, moorland, heath, downland and common. Black grouse during the winter gather at residual patches of heather moorland at relatively low altitudes, which were mapped as Open Access land. Field surveys were conducted in winter 2004/ 05 to ascertain the extent and importance of these sites. A total of 52 heather moorland areas were identified, 30 were areas of enclosed moorland and 22 unenclosed moorland. A total of 143 males and 249 females were recorded in the enclosed areas, at a mean density of 55 + 14 SE birds per km2. Enclosed areas were on average 0.68 + 0.13 SE km2. A total of 61 males and 114 females were recorded in the unenclosed areas, at a mean density of 11 + 2 SE birds per km2. Unenclosed moorland areas were on average 0.98 + 0.11 SE km2. Black grouse may be susceptible to increased recreational disturbance at winter feeding areas. As a precautionary approach, Natural England excluded human access from these areas from 1st October to 31st March.