This grouse has strongly different male and female plumage. In Siberian taiga, males gather at visible display sites in spring, calling and fanning their tails during courtship.
The male is larger, with a blue-black neck and broad greenish chest band. The female is lighter and mottled brown. Both sexes have red fleshy patches above the eyes.
Black-billed Capercaillies inhabit forests from eastern Siberia to northern Mongolia and beyond. The subspecies T. u. stegmanni occurs in the Khentej Mountains. At Gorkhi-Terelj National Park, males gathered to court females in old-growth Siberian larch forest.
From 29 April to 20 May 2011, six males and three females were observed at one lek. It lay about 200 m from the southern forest edge, adjoining open grassland where birds preferred feeding on the first shoots of grasses and forbs.
The first female arrived on 3 May; mating was recorded on 7, 8 and 9 May. Four fights between males were observed. Old larch forest and newly growing grassland occurred together, bringing feeding and breeding activities into the same spring landscape.
An extinction-risk assessment has not been added yet.
The 2012 Khentej report identified old-growth forest protection as fundamental for conserving the Mongolian subspecies. Nearby grassland was used for spring feeding. Regional conservation can retain the larch forest used for breeding together with adjacent feeding habitat.