Nest: Forsman (1976) found spotted owls nesting in the holes of living old-growth conifers, particularly Douglas-fir. Nest trees typically had secondary crowns and broken tops caused by parasite infection. Cavities were located inside the tops of hollow trunks 62 to 180 feet above ground. Dunn (1901) reported spotted owls nesting in cavities in live and dead oak and sycamore trees. Spotted owls also nest in cavities in cliffs, and occasionally in abandoned nests of other large birds (Bent 1938). Food: The major food items of the spotted owl are mammals and birds, with occasional insects and amphibians. Forsman (1976) found that mammals made up 90 percent of the total biomass taken; the major prey species were flying squirrels and wood rats. Marshall (1942) examined 23 pellets and stomach contents of 5 spotted owls and found 6 bats, 4 mice, 31 crickets, 12 flying squirrels, 1 mole, 1 shrew, 4 songbirds, 2 smaller owls, and 1 amphibian. Boreal owl _Aegolius funereus_ L 10″ W 24″ [Illustration] Habitat: This northern owl is normally found in the mixed conifer-hardwood forests of Canada (Peterson 1961). One juvenile reported in Colorado during August suggests that this owl may nest in the southern Rocky Mountains (Bailey and Niedrach 1965). Boreal owls are confined to evergreen woods and dense alder, white pine, and spruce forests. Nest: Old flicker and pileated woodpecker holes are preferred, usually at a height of 10 to 25 feet (Fisher 1893, Preble 1908, Tufts 1925, Lawrence 1932). Conifer snags seems to be preferred for nest trees, although hardwoods have been used (Bent 1938). Food: The main portion of the boreal owl’s diet consists of small rodents. Mendall (1944) examined the contents of 20 stomachs in Maine and found 73 percent mice (chiefly meadow voles) and 20 percent short-tailed shrews. Pigeons and grasshoppers made up the remaining 7 percent. In Ontario, Catling (1972) found 86.2 percent meadow voles, 5.6 percent deer mice, 4.2 percent star-nosed moles, 2.7 percent masked shrews, and 1.4 percent short-tailed shrews. Small birds, bats, insects, amphibians, and reptiles are also occasionally eaten (Karalus and Eckert 1974). Saw-whet owl _Aegolius acadicus_ L 7″ W 17″ [Illustration] Habitat: Saw-whet owls are small, nocturnal hunters of the deep north woods. They nest in the Rocky Mountains up to about 11,000 feet (Bailey and Niedrach 1965). This widely distributed owl nests in most of the forest types throughout the northern half of the United States, but only rarely do they nest as far south as central Missouri.