Nest loss in capercaillie (N=174) and black grouse (N=81) was calculated according to Mayfield (1975) based on nests from radio-equipped hens (N=77) and nests found by other methods … Black grouse. Singing and displaying bird in frosty morning. Mating call. Black grouse nest on the ground, in tall (40 cm/16 inches), reasonably dense vegetation, usually mature heather or rushes. The female makes a shallow depression and lines it with grasses and moss. Black grouse or blackgame or blackcock, Lyrurus tetrix. Lekking bird on the frosty bog in the spring. Most leks in Britain hold only 5-10 birds nowadays, but some large leks of over 30 birds are known. Before the mid-1970s a mean of 19 % of capercaillie and 13 % of black grouse nests were observed depredated, afterwards the losses have increased to a level of about 45 % of detected capercaillie and 39 % of detected black grouse nests. Black grouse are typically regarded as birds of early successional forest, either coniferous or birch, and of forest-edge habitats. Following reductions in the extent of natural forests, black grouse are now found in structurally similar habitats, such as mosaics of moorland and heathland, early stages of coniferous plantations, rough grazings and traditionally managed meadows. The relationship between nest loss in boreal forest grouse and the fluctuations in small rodents was studied at Varaldskogen in southeast Norway during 1979–1986, covering two complete rodent cycles. The black grouse is one of only three British bird species that exhibit lekking behaviour. Lekking This interesting phenomenon involves blackcocks displaying on a traditional lekking site. She lays 6-11 eggs, some time between late April and early June (depending on altitude and how far north it is). 46 black grouse nest in Hedmark and Nord-Trøndelag counties in Norway by digital wildlife camera technology.