During the autumn months, we want to share more information about two bird species that have recently appeared in many social media posts by residents of Latvia – the western capercaillie (Tetrao urogallus) and the black grouse (Lyrurus tetrix). While these birds might seem similar at first glance, they differ in both appearance and behavior.

In this article, we will explain how to distinguish between these two species and provide more details about their characteristics and conservation.

One of the main differences between the two species is their size, especially among the males. The black grouse is roughly the size of a chicken, while the western capercaillie is closer in size to a turkey. Distinguishing between the females of these species can be more difficult, as the size difference is smaller, and both females have a brown mottled coloration. However, one "cheat code" is the rusty-orange coloration on the breast of the capercaillie female.

Western capercaillies feed on pine needles during winter, whereas black grouse are often seen eating birch buds in winter, where they are easily visible on bare birch trees from a distance. Both species may spend nights in the winter sleeping under snow (if it's deep enough), as it provides insulation and warmth.

Western Capercaillie (Tetrao urogallus)

The male is bluish-black with a greenish sheen on the chest. Its wings are black-brown with a white shoulder patch, and the tail, belly, and sides have white spots. The female is smaller, with a reddish-brown mottled appearance and a brown crescent-shaped patch on the chest.
For most of the year, the western capercaillie feeds on pine needles, while in spring, the flowers of cotton grasses become important, and in summer, it feeds on various buds and flowers, especially blueberry.

In spring, the species is known for its elaborate courtship ritual, where males gather at specific sites (called leks) to sing and mate with females. The males are polygamous

The nest is built on the ground near tree roots or in similar locations, with a clutch of 5–11 eggs. There is one brood per year, and the young are precocial. The female raises the young on her own. The western capercaillie is a resident species.

Most of the western capercaillie lekking areas are dominated by pine forests. These leks are typically located in more natural forests with plenty of fallen trees, dry areas, and old trees. The capercaillie mainly leks in forests over 60 years old.

The species is threatened by various forms of forestry activities: habitat fragmentation, replacement of old forests with new stands, replacement of pine with spruce, and more. The species is also threatened by road infrastructure.

The project has assessed the species as endangered (EN), meaning it faces a very high risk of extinction in the wild.

Black Grouse (Lyrurus tetrix)

The black grouse is a chicken-sized bird. The male has black plumage with a violet sheen and a white under-tail. Its tail is lyre-shaped, and it has red eyebrows. The female is smaller and reddish-brown. Both sexes have a white stripe on the wing in flight, but the female's stripe is narrower.
The black grouse is a social bird, especially the males, which stay in groups year-round.
Adult birds feed on plant-based food, including undergrowth plants (such as lingonberries, blueberries, and heather) as well as buds, shoots, and flowers of trees like birch and alder.

The young chicks feed mainly on insects during the first weeks of life and gradually transition to plant-based food.

In spring, males gather at leks, where they sing, fight, and mate with females. The males are polygamous. The nest is built, eggs are incubated, and the young are raised by the female alone.
The nest is on the ground, typically near a tree trunk or under the cover of shrub branches, with 6–12 eggs per clutch. There is one brood per year, and the chicks are precocial. The black grouse is a resident species.

The black grouse inhabits forest edges, primarily in transitional habitats between forests and open landscapes – forest edges, young regenerating stands after fires, windthrow areas, and clear-cuts, as well as agricultural land adjacent to forests, shrublands, and moss and grass bogs. The presence of trees is important for the black grouse, but they should not be in dense stands.

In Latvia, the black grouse can be hunted from September 1 to December 31, though hunting is minimal.
The species is threatened by forestry activities that fragment habitats, increase predation risk, and cause disturbance. Habitat degradation also occurs due to the drainage of bogs. Significant threats also include predation and disturbance from recreational activities.

The project has assessed the species as vulnerable (VU).