Reports from hunting districts indicate that the number of black grouse had already declined from 33 000 in 1977 to 5 000 in 1994. As a result, black grouse became a protected species in 1995. Its decline is attributed mainly to the increase in predators such as fox, badger and marten, and nest destruction by growing populations of the common raven, e.g. in coniferous lowland forests of the south-west (Merta et al., Another key factor is habitat destruction.