Boreal owl
Aegolius funereus
L 10″ W 24″
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).