Bird of the Month: Northern Hawk Owl
Written by Andy McCormick
Andy McCormick, Volunteer and Former Board President of Eastside Audubon
The Northern Hawk Owl is a bird of the circumpolar boreal forest but in irruptive years it can make a rare winter visit to Washington.
The Northern Hawk Owl is a small owl which is active in daylight while hunting from the top of a tree. Its head looks disproportionally large because vertical black markings frame its facial disk. The overall brown plumage can vary among these owls and some individuals can look two-toned because the head often looks gray. White spots trim the wings and brown barring below extends from the upper chest to the tail. Its long tail resembles that of an accipiter and provides a control rudder for quick manuverability. Observers will often find the Hawk Owl perched atop a conifer in a sparsely forested area. Photos, videos, and vocalizations of the Northern Hawk Owl can be found at the Macaulay Library.
APTLY-NAMED HAWK-LIKE OWL
Northern hawk owl
Scientific Name: Surnia ulula
Length: 16”
Wingspan: 28”
Weight: 11 oz (320 g)
AOU Alpha Code: NHOW
Among the owls, the Northern Hawk Owl is distinctive in its resemblance to hawks and falcons. Like other raptors it hunts by sight in the daytime. Its flight resembles that of an accipiter such as a Coopers’s Hawk both in its flap-and-glide flight pattern and its low-flying approach to prey. At times, the Hawk Owl will stoop from a perch while hunting small rodents like an American Kestrel. Its wings in flight also resemble the pointed wings of a falcon.
The Northern Hawk Owl is the only bird in the genus “Surnia, a Latinized word coined by A. M. C. Dumeril (1774-1860), a French zoologist, probably from the Greek surnion, a bird of ill omen” (Holloway). Today, however, birders think more highly of the Hawk Owl. Its rarity in latitudes south of the arctic increases the desire of birders and photographers to see it. They greet a sighting of a Hawk Owl south of the Canadian border with excitement and a willingness to travel long distances to enjoy this very cool owl.
A MOVABLE BREEDER
The Northern Hawk Owl thrives on voles and other small rodents and will vary its breeding locations to seek a good population of voles. As a consequence, Hawk Owls may be abundant in one area one year and absent the next (Duncan and Duncan). The Hawk Owl prefers semi-open areas near spruce and other conifers which provide good perches with open sight lines for foraging. Hawk Owls will build a nest in a tree cavity, atop a broken snag, or in an old nest of a hawk or crow lining it with wood chips and grasses and sometimes with feathers which the female plucks from her breast (Bent). Usually, 5-7 eggs are deposited and only the female incubates the eggs which hatch in 4-5 weeks. As they mature, owlets climb around the nest until their first flight occurs in another 5-6 weeks. The young remain with the parents for about six months before dispersing (Kaufman).
STATUS AND DISTRIBUTION
The Northern Hawk Owl is a circumpolar species which breeds from Alaska to Newfoundland north to the tree line and south to roughly mid-latitude of Canada’s southern provinces. It also breeds in the boreal forests of Eurasia from Scandinavia across Russia, Siberia, and Mongolia. This owl’s remote breeding area and its nomadic breeding habit make the Hawk Owl difficult to study and as a result we have only estimates of its North American population which may be between 10,000 and 50,000 individuals. A similar population may exist in Scandinavia and Russia (Duncan and Duncan). The Hawk Owl’s inaccessibility from humans has likely allowed its population to have remained stable for the past 100 years.
The Northern Hawk Owl is rare in Washington. Since 1924 there have been 31 records accepted by the Washington Bird Records Committee (WBRC, Washington Ornithological Society). All but one of these were in Eastern Washington counties. The one Western Washington record was of a specimen found on Whidbey Island. The most recent record was in Spokane County in January 2012. That year’s report of the WBRC indicated that observations in Washington have become more regular since the year 2000, and the committee removed the Hawk Owl from the state review list. Records in eBird show more recent observations, but eBird considers the Northern Hawk Owl a sensitive species and does not list the exact locations of recent observations.
Photo credit Thomas Landgren. References available upon request from amccormick@eastsideaudubon.org.
References available upon request from amccormick@eastsideaudubon.org
Visit the Eastside Audubon Bird Gallery to read Bird of the Month articles covering over 200 bird species.