Snags with old woodpecker holes provide homes for swallows, chickadees, nuthatches, bluebirds, owls, and other cavity_nesting birds that are rarely able to excavate their own nest sites. Snags provide ideal hunting perches for Red_tailed and Rough_legged Hawks, Bald Eagles, Hawk Owls, Great_horned Owls, and other raptors. Snags provide "songposts" to a wide variety of birds. Many small birds use songposts sticking above other vegetation to sing (to attract mates and proclaim nesting territory boundaries) and to perch on when looking out for predators and/or other birds.
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.