Western Capercaillie

Tetrao urogallus

The western capercaillie (Tetrao urogallus), also known as the Eurasian capercaillie, wood grouse, heather cock, cock-of-the-woods, or simply capercaillie , is a heavy member of the grouse family and the largest of all extant grouse species. The heaviest-known specimen, recorded in captivity, had a weight of 7.2 kilograms (16 pounds). Found across Europe and the Palearctic, this primarily-ground-dwelling forest grouse is renowned for its courtship display. This bird shows extreme sexual dimorphism, with males nearly twice the size of females. The global population is listed as "least concern" under the IUCN, although the populations of central Europe are declining and fragmented, or possibly extirpated.

The wood grouse is one of two living species under the genus Tetrao, which also includes the lesser-known black-billed capercaillie.