Northern Hawk Owl
Surnia ulula
Morphology 3
Northern Hawk Owls' plumage is compact, in contrast to the down feathers of boreal owls (344-349g, 36-43cm;14-17in length and 79-89cm;31-35in wingspan) (Voous 1988). They are dark chocolate in color with white spots. The breast and belly regions are creamy white crossed by horizontal, cinnamon brown bars. Their poorly developed facial disks are framed by black lines. Often referred to as the "earless" owl, they lack true ear tufts; the external ear openings are elliptical (de la Torre 1990). Both legs are fully feathered (Duncan and Duncan 1998).
Trophic strategy 4
Lives primarily in dense coniferous or coniferous-deciduous forests, which adjoin open areas. It prefers mountainous ranges where open areas and perches are readily available. The abundance of prey dictates location of habitats (Duncan and Duncan 1998). This species will not inhabit dark impenetrable spruce-fir forests (Voous1988).
Northern Hawk Owls prey on small mammals (voles, lemmings, mice, shrews, snowshoe hares, cottontails, moles, squirrels and rats). During the summer, they consume primarily rodents, and in the winter they shift to birds (ptarmigan and grouse). The extent to which they prey on birds is unknown. They share similar hunting habits with boreal owls. They hunt both during the day and the night (Duncan and Duncan, 1998).
The Great Horned Owl serves as the Northern Hawk Owl's primary predator. At night the Great Horned Owls kill roosting owls while they are resting or enter nests and take eggs or young. To avoid predation, the Northern Hawk Owl flattens its plumage and stands erect. Also, it attempts to intercept predators that attack its nest (Duncan and Duncan 1998).
"cool facts" 5
A bird of boreal forests, the Northern Hawk Owl is distinctive among owls for its morphology and behavior. In winters of food scarcity, it irrupts southward into southern Canada and the northern United States. The Northern Hawk Owl can detect prey by sight at a distance of up to 800 meters (half a mile). Though it is thought to detect prey primarily by sight, the Northern Hawk Owl can find and seize prey under 30 cm (1 foot) of snow.
Sources and Credits
- (c) roy pilcher, some rights reserved (CC BY-NC), uploaded by roy pilcher
- (c) Krzysztof Blachowiak, some rights reserved (CC BY), https://www.flickr.com/photos/blachowiak/10885279335/
- Adapted by Yukon Conservation Data Centre from a work by (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31425085
- Adapted by Yukon Conservation Data Centre from a work by (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/31425089
- Adapted by Yukon Conservation Data Centre from a work by Public Domain, http://eol.org/data_objects/27672604
More Info
iNaturalist.ca Map
| Animal | Bird |
|---|---|
| Color | grey |
| Bird | owl |
