Aegolius funereus
(Boreal Owl)


Order: Strigiformes
Order Description: Owls
Family: Strigidae
Family Description: Typical Owls

Physical Description:
8 1/2-12" (22-30 cm). Short-tailed, flat-headed, chubby owl; lacks ear tufts and very tame. Chocolate brown with fine white spots thickly crowded on head. Large facial disk is pale grayish with dark border, yellow eyes, and yellow bill. Immature is dusky brown; eyebrows dirty whitish or gray; belly obscurely blotched.

Similar Species- Northern Saw-whet Owl, Hawk Owl, Northern Pygmy-owl, Screech-owls

Song:
Spring call is similar to the tolling of a soft bell or dripping water. Also a series of high-pitched whistles, rising slightly.

Distribution:
Breeds from central Alaska, east across portions of Canada to Labrador and New Brunswick, and south to northeastern Washington, Idaho, Montana, and northeastern Minnesota, and further south in mountains to Colorado and New Mexico. Winters mainly in breeding range, and south irregularly to northern United States.

Habitat:
Found in coniferous forests, mixed forests, thickets of alder, aspen, or stunted spruce, and muskegClick word for definition bogs. Generally found in spruce/fir in Rockies. In Idaho, nests in mixed conifer, spruce/fir, Douglas-fir, and aspen stands.

Diet:
Eats mainly small mammals (often red-backed voles, but also shrews, pocket gophers, and deer mice). Will sometimes eat birds and insects.

Ecology:
Hunts from perch; captures prey on ground. cachesClick word for definition food. Nests in abandoned or natural cavity in standing snag in older forests with complex physical structures. Defends nest site only. roostsClick word for definition in dense cover by day; forages mostly at night. Idaho study found home range averaged 1451 ha in winter and 1152 ha in summer. Best foraging habitat was in spruce/fir stands.

Reproduction:
In Idaho, nesting occurs in mid-April to late May. Female incubatesClick word for definition 2-5 eggs for 25-36 days. Young fledgeClick word for definition at about 27-31 days, are independent at 5-6 wk, and become sexually mature by 1 yr.

Conservation:
Element Code: ABNSB15010
Status: Protected nongame species
Global Rank: G5
State Rank: S2
National Rank: N4

Important State References:
Hayward, G.D., P.H. Hayward, and E.O. Garton. 1993. Ecology of boreal owls in the northern Rocky Mountains, USA. Wildl. Mono. 59.


Design by Ean Harker©1999, 2000.
Written by Jason Karl, 2000.