The hazel grouse (Tetrastes bonasia) dwells in lush, mixed forests. It needs spruce thickets to hide in as well as bilberry forests, birch trees and grey alders to feed on. Hazel grouse live in pairs. They pair up in the autumn, after which they stay with the same mate. Their broods are always led by the female.
The hazel grouse is one of the most sedentary birds in Finland. The size of its range is approximately ten hectares. The hazel grouse stays in the forest at all times, never crossing open sea areas or large clearings.
In Helsinki, grouse can be found in the forested edges of the city, such as in Vuosaari, which is connected to the extensive forests of Sipoonkorpi. In Sipoo, you can also find the western capercaillie (Tetrao urogallus), which requires extensive, uninterrupted forests for its habitat. There is also a small population of black grouse in Helsinki’s archipelago.