Winter for the black grouse

Digging a hole

The black grouse digs itself deep into the snow to retain body temperature. Snow is a good isolator and reduces the loss of heat. The grouse lies in its snow cave about 95 percent of it's day in the winter.

Critical temperature

Below 5 degrees Celsius the grouse's muscles begin to shiver. This increases the metabolism and more heat is generated. In this way the grouse keeps its normal body temperature.