They vary in weight from 1 - 14 lbs. Males are often larger than the females and, particularly in species which lek, more colourful. Several species of grouse exhibit communal courtship. During this time all the mature males in an area gather at a specific site, generally one used for this purpose year after year, and defend and display within a small territory. Some of the territories are more valuable than others and the top male normally secures the most matings.
Females come to the leking ground to choose and be mated by a male.
In these species the female makes the nest and cares for the eggs away from the leking ground entirely on her own. The species in which communal courtship is most well developed are the Black grouse, Lyrurus tetrix , the Capercaillie, Tetrao urogallus , the Sage Grouse, Centrocerus cerophasianus , and the Prairie Chicken, Tympanuchus cupido . These birds occupy breeding territories as individual pairs - which they defend against other pairs. Even in these cases it is usually the female who is responsible for incubating the eggs. Most species nest on the ground in simply nests of twigs into which 5-12 cryptically coloured eggs are laid.