Black grouse are declining woodland edge and moorland birds whose lek (communal mating display) sites require open, boggy habitat and freedom from disturbance during the critical April breeding season.
Male black grouse at leks engage in intense territorial displays that are energetically costly. Disturbance that causes repeated flight from leks wastes critical energy reserves. Females that cannot access undisturbed leks fail to mate. Young birds that encounter disturbed leks may abandon site fidelity, preventing lek site re-establishment. The welfare of individual birds is directly affected by the quality of lek site protection.