Surnia ulula - (Linnaeus, 1758)
Northern Hawk Owl
Other English Common Names: northern hawk owl
Taxonomic Status: Accepted
Related ITIS Name(s): Surnia ulula (Linnaeus, 1758) (TSN 177898)
French Common Names: chouette épervière
Unique Identifier: ELEMENT_GLOBAL.2.103144
Element Code: ABNSB07010
Informal Taxonomy: Animals, Vertebrates - Birds - Other Birds
Image 10871

© Michael Patrikeev

 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Aves Strigiformes Strigidae Surnia
Genus Size: A - Monotypic genus
Check this box to expand all report sections:
Concept Reference
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Concept Reference: American Ornithologists' Union (AOU). 1998. Check-list of North American birds. Seventh edition. American Ornithologists' Union, Washington, D.C. [as modified by subsequent supplements and corrections published in The Auk]. Also available online: http://www.aou.org/.
Concept Reference Code: B98AOU01NAUS
Name Used in Concept Reference: Surnia ulula
Conservation Status
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NatureServe Status

Global Status: G5
Global Status Last Reviewed: 10Apr2016
Global Status Last Changed: 27Nov1996
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G5 - Secure
Nation: United States
National Status: N5 (05Jan1997)
Nation: Canada
National Status: N5B,N5N,N3M (29Jan2018)

U.S. & Canada State/Province Status
Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
United States Alaska (S5), Maine (S2N), Michigan (SNRN), Minnesota (SNRN), Montana (S3), New York (SNRN), North Dakota (SNA)
Canada Alberta (S4), British Columbia (S4S5), Labrador (S4), Manitoba (S3S4), Newfoundland Island (S3), Northwest Territories (S5), Nunavut (SU), Ontario (S4), Quebec (S4?), Saskatchewan (S3B,S5N), Yukon Territory (S4)

Other Statuses

Committee on the Status of Endangered Wildlife in Canada (COSEWIC): Not at Risk (01Apr1992)
Comments on COSEWIC: Reason for designation: No recent declines have been demonstrated for this relatively common species and no significant threats have been identified.

Status history: Designated Not at Risk in April 1992.

IUCN Red List Category: LC - Least concern
Convention on International Trade in Endangered Species Protection Status (CITES): Appendix II

NatureServe Global Conservation Status Factors

Range Extent Comments: BREEDS: from limit of trees in western and central Alaska to southern Keewatin and Labrador, south to southern British Columbia, central Saskatchewan, northern Minnesota, northern Michigan, and New Brunswick. WINTERS: mainly in breeding range, makes irregular invasions of northern coterminous U.S. Also occurs in Old World.

Population Size Comments: Guesstimated number of breeding pairs in Canada in the early 1990s was 10,000-50,000 (Kirk et al. 1995).

Short-term Trend Comments: Trend in Canada was reported as "?stable; little data available" by Kirk et al. (1995).

Other NatureServe Conservation Status Information

Distribution
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Global Range: BREEDS: from limit of trees in western and central Alaska to southern Keewatin and Labrador, south to southern British Columbia, central Saskatchewan, northern Minnesota, northern Michigan, and New Brunswick. WINTERS: mainly in breeding range, makes irregular invasions of northern coterminous U.S. Also occurs in Old World.

U.S. States and Canadian Provinces

Due to latency between updates made in state, provincial or other NatureServe Network databases and when they appear on NatureServe Explorer, for state or provincial information you may wish to contact the data steward in your jurisdiction to obtain the most current data. Please refer to our Distribution Data Sources to find contact information for your jurisdiction.
Color legend for Distribution Map
NOTE: The maps for birds represent the breeding status by state and province. In some jurisdictions, the subnational statuses for common species have not been assessed and the status is shown as not-assessed (SNR). In some jurisdictions, the subnational status refers to the status as a non-breeder; these errors will be corrected in future versions of these maps. A species is not shown in a jurisdiction if it is not known to breed in the jurisdiction or if it occurs only accidentally or casually in the jurisdiction. Thus, the species may occur in a jurisdiction as a seasonal non-breeding resident or as a migratory transient but this will not be indicated on these maps. See other maps on this web site that depict the Western Hemisphere ranges of these species at all seasons of the year.
Endemism: occurs (regularly, as a native taxon) in multiple nations

U.S. & Canada State/Province Distribution
United States AK, ME, MI, MN, MT, ND, NY
Canada AB, BC, LB, MB, NF, NT, NU, ON, QC, SK, YT

Range Map
Note: Range depicted for New World only. The scale of the maps may cause narrow coastal ranges or ranges on small islands not to appear. Not all vagrant or small disjunct occurrences are depicted. For migratory birds, some individuals occur outside of the passage migrant range depicted. For information on how to obtain shapefiles of species ranges see our Species Mapping pages at www.natureserve.org/conservation-tools/data-maps-tools.

Range Map Compilers: WILDSPACETM 2002


U.S. Distribution by County Help
State County Name (FIPS Code)
ID Blaine (16013), Elmore (16039), Fremont (16043), Kootenai (16055)*, Madison (16065)
MT Flathead (30029), Glacier (30035), Teton (30099)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
09 St. Marys (09040001)+
10 Teton (10030205)+, Milk Headwaters (10050001)+
17 North Fork Flathead (17010206)+, Middle Fork Flathead (17010207)+, Coeur D'alene Lake (17010303)+*, Lower Henrys (17040203)+, Big Wood (17040219)+, North and Middle Forks Boise (17050111)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Reproduction Comments: Egg dates: late April to mid-June in Alaska and arctic Canada; April-early June in Alberta. Clutch size is up to 13 (mean brood size was 6.3 in Fennoscandia, 3.7 in Yukon, 5.5 in Alaska). Incubation lasts about 25-30 days, by female. Both parents tend young, which fledge in 25-35 days, independent in about 3 months.
Ecology Comments: Tends to occur in greatest numbers in areas with temporarily high prey populations; may move long distances in response to changes in prey abundance. Population density generally is low (e.g., 4 pairs in 200 sq km in Norway; 1 pair per 500 sq km in Sweden) (Johnsgard 1988); maximum of 3 nests per 100 sq km in southwestern Yukon, Canada (Rohner et al. 1995). Home ranges in Europe ranged from 140 to 848 hectares, average 372 hectares (Baekken et al. 1987).
Non-Migrant: Y
Locally Migrant: Y
Long Distance Migrant: N
Mobility and Migration Comments: Basically nonmigratory but retreats slightly in winter from northernmost part of range (National Geographic Society 1983). Southward irruptive movements generally in year following peak in rodent population. Usually on nesting territory by mid-March in northern Alberta.
Palustrine Habitat(s): Bog/fen, FORESTED WETLAND, Riparian
Terrestrial Habitat(s): Forest - Conifer, Forest - Hardwood, Forest - Mixed, Woodland - Conifer, Woodland - Hardwood, Woodland - Mixed
Special Habitat Factors: Standing snag/hollow tree
Habitat Comments: Open coniferous or mixed forest, forest edge and clearings, old deciduous forest burns, dense shrubby areas (especially tamarack), swamps, scrubby second-growth woodland and muskeg (AOU 1983).

Nests in hollow tops of dead spruces, birches, natural tree hollows, abandoned woodpecker holes, deserted nests of crows and birds of prey (Terres 1980).

Adult Food Habits: Carnivore, Invertivore
Immature Food Habits: Carnivore, Invertivore
Food Comments: Diet often is dominated by voles, but birds (up to grouse size) may comprise the major part of the diet in winter and snowshoe hare juveniles may be important during certain nesting stages (Rohner et al. 1995). Also eats other small mammals and insects. Watches for prey from perch, swoops down on it, returns to elevated perch.
Adult Phenology: Circadian
Immature Phenology: Circadian
Phenology Comments: Active any time of day during breeding season; hunts mainly during daylight hours in winter.
Length: 41 centimeters
Weight: 345 grams
Economic Attributes Not yet assessed
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Management Summary Not yet assessed
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Population/Occurrence Delineation
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Group Name: Large Owls

Use Class: Breeding
Minimum Criteria for an Occurrence: Evidence of historical breeding, or current and likely recurring breeding, at a given location, minimally a reliable observation of one or more breeding pairs in appropriate habitat. Be cautious about creating EOs for observations that may represent single breeding events outside the normal breeding distribution.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 10 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Separation distance based conservatively on larger home ranges (greater than 800 hectares). Home ranges generally well over 100 hectares, often over 500 hectares. Northern Hawk-Owl: average 372 hectares (Baekken et al. 1987). Great Horned Owl: average 483 hectares in Yukon (Rohner 1997), average about 106 hectares in Utah (Smith 1969). Barred Owl: average 273-971 hectares (Elody and Sloan 1985, Nicholls and Fuller 1987, Mazur et al. 1998). Great Gray Owl, varied from 239-400 hectares (Craighead and Craighead 1956, Winter 1982). Barn Owl: averages range from 198-921 hectares (Byrd 1982, Colvin 1984, Hegdal and Blaskiewicz 1984, Rosenburg 1986, Byrd and Johnston 1991, Gubanyi 1989).
Inferred Minimum Extent of Habitat Use (when actual extent is unknown): 1.5 km
Inferred Minimum Extent Justification: Based on a conservatively small home range of just under 200 hectares (see Separation Justification).
Date: 02Nov2001
Author: Cannings, S.
Notes: Contains all North American owls larger than Screech-Owls, except Spotted, Long-eared, and Short-eared Owls.

Use Class: Nonbreeding
Minimum Criteria for an Occurrence: Evidence of recurring presence of wintering individuals outside their breeding area (including historical); and potential recurring presence at a given location. Occurrences should be locations where the species is resident for some time during the appropriate season; it is preferable to have observations documenting presence over at least 20 days annually. Be cautious about creating EOs for observations that may represent single events.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 10 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Separation distance based conservatively on larger home ranges (greater than 800 hectares; see Separation Justification in Breeding class).
Inferred Minimum Extent of Habitat Use (when actual extent is unknown): 1.5 km
Inferred Minimum Extent Justification: Based on a conservatively small home range of just under 200 hectares (see Separation Justification in Breeding Class).
Date: 16Oct2002
Author: Cannings, S.
Notes: Contains all North American owls larger than Screech-Owls, except Spotted, Long-eared, and Short-eared Owls.

Use Class: Roost
Minimum Criteria for an Occurrence: Evidence of recurring, nonbreeding, communal roosting at a given location; reliable observation of multiple individuals roosting in a distinct habitat patch in multiple years. To avoid creating EOs for ephemeral situations, there should be evidence of communal roosting over at least two different (though not necessarily consecutive) nonbreeding seasons.
Separation Barriers: None.
Separation Distance for Unsuitable Habitat: 10 km
Separation Distance for Suitable Habitat: 10 km
Separation Justification: Separation distance is arbitrary. Pertinent biologically based separation criteria do not exist.
Date: 25Oct2012
Author: Hammerson, G
Population/Occurrence Viability
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U.S. Invasive Species Impact Rank (I-Rank) Not yet assessed
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Authors/Contributors
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Element Ecology & Life History Edition Date: 01Apr1996
Element Ecology & Life History Author(s): Hammerson, G.

Zoological data developed by NatureServe and its network of natural heritage programs (see Local Programs) and other contributors and cooperators (see Sources).

References
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