Seed_eating birds that can be attracted to feeders include pine siskins, sparrows, grosbeaks, redpolls, and crossbills. These species also eat suet, but seeds will attract them to your feeder. Unsalted sunflower seeds, thistle seeds, raw crushed peanuts, millet, scratch feed, various wild grains, and canary seeds are welcomed. Commercial wild bird seed mixes can be used, but they often contain filler seeds that are not eaten by many species. Often, you can mix your own "wild bird food" more economically. Seeds can be purchased from local feed, variety, and pet stores, or ordered from catalogs. When you first start your feeder, experiment with various seeds and find out which are preferred by the birds in your area.
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.