Northern Saw-whet Owl - Aegolius acadicus
General Description
Round-headed, eyes yellow, bill black. Facial disk reddish/brown; forehead has short white vertical streaks. Ventrally reddish/brown streaking extends from neck to belly. Dorsally, brown with white spots. Juvenile has dark reddish/brown facial disk and white forehead. Upper chest is reddish/brown grading into dark rust belly and flanks. Juveniles molt into adult-like plumage by early winter. SIZE: seven to eight inches. WEIGHT: three to four ounces. VOICE: A monotonous, "Toot, toot, toot¿," given rapidly and consistently throughout the night. Similar to one of the northern pygmy-owl's calls.
Diagnostic Characteristics
Boreal owls are slightly larger, have a yellow/white bill, rectangular head, whitish facial disk, and are darker brown overall with no reddish tinge.
Distribution
Montana Range
Observations in Montana: 321
Montana CountiesBeaverhead, Big Horn, Broadwater, Carbon, Carter, Cascade, Custer, Deer Lodge, Fergus, Flathead, Gallatin, Garfield, Glacier, Golden Valley, Granite, Hill, Jefferson, Judith Basin, Lake, Lewis and Clark, Liberty, Lincoln, Madison, Meagher, Mineral, Missoula, Park, Phillips, Powder River, Powell, Ravalli, Rosebud, Sanders, Silver Bow, Stillwater, Teton, Valley, Wheatland, Yellowstone
Migration
Migratory although some birds may remain throughout winter.
Habitat
Most common in coniferous forests; however, they can be found in deciduous trees along watercourses.
Food Habits
Predominately small mice, although small birds and insects are probably also eaten.
Reproductive Characteristics
Begins nesting in April. Nests in woodpecker holes and possibly natural cavities. Clutch size four to six. Incubation approximately 30 days (FWP). Young just out of nest reported on May 29 and Jul 12. Egg dates probably similar to Alberta: Apr 18- Jun 8.
Citations & Sources
- Holt, D. and Becker, D. 1990. Indentification of Montana's Owls. Montana Outdoors. March/April 1990.