Winter Roost Boxes. Chickadees, owls, and woodpeckers that remain in Alaska during winter use natural tree cavities and birdhouses as roosting sites. These roosting sites provide protection from wind and snow and extra insulation against the cold. Any birdhouse can provide a winter roost site if it is properly built, but better insulated birdhouses can also be constructed. Try placing perches on the inside of a birdhouse. During severe cold several chickadees sometimes share their body heat by roosting together in a single cavity.
Snags provide "hawking" perches for flycatchers and resting perches for swallows. Flycatchers perch on a branch, fly out to snatch insects, and then return to the same branch to watch for other insects. Large natural cavities, formed in snags by decay, often provide homes for a variey of mammals including marten, porcupine, bats, bushy_tailed woodrats, northern flying squirrels, and other species. When left to decay and fall over naturally, large hollow snags may provide den sites for larger animals like mink, lynx, red fox, and wolverine. To help provide homes for this wide variety of animals, leave dead trees standing whenever possible, particularly snags larger than 6 inches in diameter and/or any containing woodpecker holes or other cavities.