The Owl Pages

Northern Hawk Owl ~ Surnia ulula

Introduction

The Northern Hawk Owl is a medium sized Owl with no ear-tufts, a whitish face and long pointed wings.

Photo Gallery (20 pictures)

  • Northern Hawk Owl
  • Northern Hawk Owl
  • Northern Hawk Owl
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  • Northern Hawk Owl
  • Northern Hawk Owl
  • Northern Hawk Owl
  • Northern Hawk Owl
  • Northern Hawk Owl
  • Northern Hawk Owl
  • Northern Hawk Owl
  • Northern Hawk Owl

Sound Gallery

Typical call - Floatplane Lake, Alaska, USA. July 1999. CC Dan Lane.

Information

Description: The facial disc is whitish, broadly rimmed blackish at the sides. Eyebrows are white, and eyes are pale yellow (golden yellow in juvenile). The bill is pale yellowish-green and the cere pale greyish-brown. Upperparts are dark grey to dusky greyish-brown, with the crown densely spotted whitish and the nape with indistinct false eyes. Mantle and back are dusky grey with some whitish dots. Scapulars are mainly white, forming rather broad white bands across shoulder. Flight feathers are dark grey-brown with rows of white spots. the Tail is long and graduated and dark greyish-brown with several narrow whitish bars. Underparts are whitish, barred with Greyish-brown. Legs and toes are feathered. The soles of the toes are dirty yellow, and claws are dark brown with blackish tips.

Size: Length 36-41cm. Wing length 218-258mm. Tail length 160-204mm. Weight 215-392g. Females are heavier than males.

Habits: A largely diurnal bird. Flight is straight with rapid wingbeats and open-winged glides; often hovering, perching in exposed sites such as a treetop or post. Flicks tail when excited. Not social - seen mostly singly or in pairs.

Voice: Typical male call is a rapid, melodious, purring trill of up to 14 seconds long, which consists of about 11 to 15 notes per second. It begins softly, rises slightly in pitch and increases to a vibrating trill before breaking off abruptly. This is repeated at various intervals. Females utter a similar, higher-pitched, less clear song. Both sexes give a piercing kiiiiirrl or a kestrel-like kwikikikikkik call when excited. Screeching calls are also uttered. A soft uhg or uih is given as contact between pairs. Young beg with a drawn-out chchchiep.

Hunting & Food: Takes mainly small mammals as prey, mostly lemmings and voles. Will also take birds, frogs and occasionally fish. Prey weight is normally below 70g. Hunts by searching from a lookout, then quickly flying to swoop down on prey. Has been observed hovering also.

Breeding: Male advertises potential nest sites, and the female selects one. Nests in Cavities on top of broken trunks, natural tree hollows, abandoned holes of large woodpeckers. Will accept nest boxes, and occasionally use a stick nest of a larger bird. Laying normally occurs in April and the first half of May. Clutch sizes are usually between 5 and 13 eggs, each 36-44 x 29-34.4mm. Eggs are laid at 1-2 day intervals, and incubated by the female alone for 25-30 days. During this time, the male feeds the female. After hatching, the chicks are brooded for 13-18 days, and leave the nest at 23-30 days, and can fly well by the time they are about 5-6 weeks old. They become independent of their parent's care towards the end of August. They become sexually mature towards the end of their first year. Pairs are monogamous during breeding season.

Habitat: Open boreal coniferous forest with clearings and moors in lowlands or mountains. Hunts in semi-open country with scattered trees or groups of trees.

Distribution: Eurasia from Norway, Sweden and Finland east through Siberia to Kamchatka, Sakhalin, and North China, in Central Asia south to Tien Shan. North America from Alaska east to Labrador.
Moves widely within its area of distribution, breeding where food is abundant. In some Autumns, invasions (mainly juveniles) occur in areas south of its normal range.

Range of Northern Hawk Owl (Surnia ulula)
Range of the Northern Hawk Owl Surnia ulula

Status: Not threatened or endangered.

Original Description: Linnaeus, Carolis. 1758. Systema Naturae ed. 10, p. 93.

References:
Boyer and Hume. 1991. "Owls of the World". BookSales Inc.
Campbell, Wayne. 1994. "Know Your Owls". Axia Wildlife.
del Hoyo, Elliott & Sargatal. 1999. "Handbook of the Birds of the World: Barn Owls to Hummingbirds". Buteo Books.
Duncan, James R.. 2003. "Owls of the World: Their Lives, Behavior and Survival". Firefly Books.
Johnsgard, Paul A.. 2002. "North American Owls: Biology and Natural History". Smithsonian.
König, Claus & Weick, Friedhelm. 2008. "Owls: A Guide to the Owls of the World (Second Edition)". Yale University Press.
König, Weick and Becking. 1999. "Owls: A Guide to the Owls of the World". Yale University Press.
Voous, Karel H.. 1988. "Owls of the Northern Hemisphere". The MIT Press.

See also: Other owls from North America, Europe, Asia, Genus: Surnia.

Page by Deane Lewis. Last updated 2015-11-11.