Red grouse by sheep. Conservation measures taken on foot of the judgment have seen the population in the area double from 400 to 800. The red grouse is considered a game bird and is shot in large numbers during the shooting season which traditionally starts on August 12, known as the Glorious Twelfth. There is a keen competition among some London restaurants to serve freshly killed grouse on August 12, with the birds being flown from the moors and cooked within hours. Shooting can take the form of 'walked up' (where shooters walk across the moor to flush grouse and take a
Grouse a considerable part of the vertebrate biomass in the Arctic and Subarctic. Their numbers may fall sharply in years of bad weather or high predator populations—significant grouse populations are a major food source for lynx, foxes, martens, and birds of prey. However, because of their large clutches, they can recover quickly. The three tundra species have maintained their former numbers. The prairie and forest species have declined greatly because of habitat loss, though popular game birds such as the red grouse and the ruffed grouse have benefited from habitat management. Most grouse species are listed by the IUCN as "least