Snow and Cold
Snowshoes
One problem is the deep, loose snow into which the willow grouse might easily sink. But its feet are covered with feathers which increase the tread area by 400 percent and make it easier for the grouse to walk on snow.
Winter coat
In order to increase the retention of body heat, the plumage is thicker in winter than in summer. It has an extra down on the shaft of its feathers. The down becomes especially big during winter. See the feathers on the snow!
In hiding
Another way for the willow grouse to protect itself against the cold is to dig a burrow in the snow. It digs a half-metre-long tunnel that ends in a chamber where it lies down to rest. The tunnel is filled in with snow.
