Nest: Although hollow trees are the usual location, ground nests under thick cover or in rock crevices are not uncommon. A wide variety of other locations have been reported such as chimneys, hawk nests, bridge supports, and old buildings. The species of tree used for nesting and the height of the cavity are apparently unimportant (Foreman 1976). Nest sites are usually close to water (Bellrose 1976) and are used repeatedly, probably by the same female (Palmer 1976). Artificial nest boxes have been accepted, especially in Europe. Preferred dimensions are 9.1 to 11 inches wide, and 33.5 to 39.4 inches high, with 4.7 × 4.7-inch entrances, 19.7 to 23.6 inches above the base of the nest box (Johnsgard 1975). Food: Programs to reduce populations of this fish-eating merganser have increased trout and salmon production in several areas, at least temporarily. Generally, common mergansers are opportunistic feeders with salmon taken extensively in some areas and suckers, chubs, and eels in others. In warm-water areas, food is usually rough and forage fish such as carp, suckers, gizzard shad, perch, and catfish. In some areas, water plants, salamanders, insects, or molluscs may be important in the diet of this species (Palmer 1976). Turkey vulture _Cathartes aura_ L 25″ W 72″ [Illustration] Habitat: Turkey vultures soar over most of the forest types of the United States and southern Canada, with the exception of the pine and spruce-fir stands in the extreme northeastern United States. In search of food this common carrion eater makes use of the forest openings created by roads, powerline rights-of-way, clearcuts, and abandoned fields. Nest: Preferred nest sites are often at a premium because of the bird’s large size and the shortage of large snags. The smell of carrion around the nest necessitates a well-protected site to lessen predator losses. The nest site is almost always at or near ground level (Bent 1937). Although nesting sites are commonly located in hollow trees or hollow logs lying on the ground, these vultures will nest on cliffs, in caves, and in dense shrubbery (Gingrich 1914, Townsend 1914). These birds will return to the same nesting site year after year unless the site has been severely disturbed (Jackson 1903, Kempton 1927). Food: Turkey vultures are scavengers and carrion-eaters, often hunting along roads where animals have been struck by automobiles. They feed on snakes, toads, rats, mice, and other available animal matter. Often a dozen or more vultures will gather at and feed on a large carcass. Black vulture _Coragyps atratus_ L 22″ W 54″ [Illustration] Habitat: The black vulture is found in the southern Great Plains, southeastern pine forests, oak-hickory forests, and intermediate oak-pine forests. It is a more southern species than the turkey vulture.