Great Horned Owl

Bubo virginianus

General Status Rank: 
Secure
ELCODE: 
ABNSB05010
Common Name: 
Great Horned Owl
Scientific Name: 
Bubo virginianus
Naming References: 
B138
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Taxonomy
Group: 
Bird
Kingdom: 
Animalia
Phylum: 
Chordata
Class: 
Aves
Order: 
Strigiformes
Family: 
Strigidae
References: 
B004
General Biology

Female Age at Maturity

most individuals are not sexually active until 2 yr of age
References: 
B138

Longevity

Probably the most long-lived of North American owls: 21- 28 yr
References: 
B138
Habitat
deciduous and coniferous forests; may nest in trees, grottes, and on the ground
References: 
B004
H126
B138
Distribution

Ecozones

Southern Arctic, Taiga Cordillera, Taiga Plains, Taiga Shield, Boreal Cordillera, Boreal Plains
References: 
B004

Distribution

0.189; Uncommon permanent resident in forests below the treeline on the mainland, including up the Mackenzie Valley to Inuvik and Reindeer Station.(NWT Bird checklist project)
Score: 
G
References: 
B004
Winter Distribution Description: 
limited migration

Number of Occurrences

Probably more than 100 as widespread species in NWT
Score: 
DE
References: 
H126

Area of Occupancy

Prob. Stable
Score: 
-
References: 
LWR01
W027
Population

Population Size

likely abundant in breeding range; prob. Less than 10 00 and more than 1000 (unkown)
Score: 
DE
References: 
H126
Trends

Trends

National trend 3 (Stable) but showed some declines over the past 30 yrs (LWR01); Strong decline in Canada, sustained over the past three decades. However, Breeding Bird Survey (BBS) data poor, as this species is detected in low numbers and is not generally calling at the time surveys are done (Houston et al. 1998). Christmas Bird Count (CBC) detects small numbers, but trends in those data may be more useful for broad-scale trends than is BBS.(W027)
References: 
LWR01
W027
Threats

Threats

limited in NWT
Score: 
C
References: 
H126

Intrinsic Vulnerability

threats limited in NWT
Score: 
-
References: 
H126
General Status Rank
Rank: 
Secure
Status Rank Description: 
Threats appear limited in NWT , widespread species; Monitoring is needed to confirm or refute evidence of decline from BBS and CBC in the south = nocturnal owl surveys (see Takats et al. 2001). Research: Investigate cause of decline (if confirmed)
S Rank: 
S4?
Decision Process Description: 
Drafted by Suzanne Carriere based on printed references. Reviewed in 2005, no change in status; Reviewed in 2010;no change; Reviewed in 2015, no change; Reviewed in 2020, no change
Last Updated: 
June 30, 2020

References

Age Of Maturity

  • Houston, C. S., D. G. Smith, and C. Rohner. The Birds of North America, Inc., Philadelphia, PA. (1998) Great Horned Owl (Bubo virginianus). The Birds of North America, Inc., Philadelphia, PA. In The Birds of North America, No. 372 (A. Poole and F. Gill, eds.). - B138 Return

Area of Occupancy

  • Downes, C.M., E.H. Dunn and C.M Francis (2000) Canadian Landbird Monitoring Strategy: monitoring needs and priorities into the new millenium.. Partners in Flight - Canada A 9-15 EC-CWS, Yellowknife (L. Wakelyn) - or communicate with Erica H. Dunn, CWS in Hull, QC, at erica.dunn@ec,gc,ca - LWR01 Return
  • Dunn, E.H (2005) National action needs for Canadian Landbird Conservation,. Canadian Wildlife Service Landbird Committee, Version 1. [http://www.cws-scf.ec.gc.ca/birds/action/index_e.cfm]. - W027 Return

Ecozones

  • Godfrey WE (1986) The Birds of Canada. National Museums of Canada Revised Edition RWED Library Call #QL685.G6 - B004 Return

Habitat

  • Godfrey WE (1986) The Birds of Canada. National Museums of Canada Revised Edition RWED Library Call #QL685.G6 - B004 Return
  • Carrière, S. (2000) Pers. communication. Ecosystem Management Biologist; RWED - H126 Return
  • Houston, C. S., D. G. Smith, and C. Rohner. The Birds of North America, Inc., Philadelphia, PA. (1998) Great Horned Owl (Bubo virginianus). The Birds of North America, Inc., Philadelphia, PA. In The Birds of North America, No. 372 (A. Poole and F. Gill, eds.). - B138 Return

Intrinsic Vulnerability

  • Carrière, S. (2000) Pers. communication. Ecosystem Management Biologist; RWED - H126 Return

Longevity

  • Houston, C. S., D. G. Smith, and C. Rohner. The Birds of North America, Inc., Philadelphia, PA. (1998) Great Horned Owl (Bubo virginianus). The Birds of North America, Inc., Philadelphia, PA. In The Birds of North America, No. 372 (A. Poole and F. Gill, eds.). - B138 Return

Naming

  • Houston, C. S., D. G. Smith, and C. Rohner. The Birds of North America, Inc., Philadelphia, PA. (1998) Great Horned Owl (Bubo virginianus). The Birds of North America, Inc., Philadelphia, PA. In The Birds of North America, No. 372 (A. Poole and F. Gill, eds.). - B138 Return

NWT Known Subspecies

Godfrey WE (1986) The Birds of Canada. National Museums of Canada Revised Edition RWED Library Call #QL685.G6 - B004 Return

Number of Occurrences

  • Carrière, S. (2000) Pers. communication. Ecosystem Management Biologist; RWED - H126 Return

Population Size

Carrière, S. (2000) Pers. communication. Ecosystem Management Biologist; RWED - H126 Return

Range Extent

  • Godfrey WE (1986) The Birds of Canada. National Museums of Canada Revised Edition RWED Library Call #QL685.G6 - B004 Return

Short Term Trends

  • Downes, C.M., E.H. Dunn and C.M Francis (2000) Canadian Landbird Monitoring Strategy: monitoring needs and priorities into the new millenium.. Partners in Flight - Canada A 9-15 EC-CWS, Yellowknife (L. Wakelyn) - or communicate with Erica H. Dunn, CWS in Hull, QC, at erica.dunn@ec,gc,ca - LWR01 Return
  • Dunn, E.H (2005) National action needs for Canadian Landbird Conservation,. Canadian Wildlife Service Landbird Committee, Version 1. [http://www.cws-scf.ec.gc.ca/birds/action/index_e.cfm]. - W027 Return

Taxonomy

  • Godfrey WE (1986) The Birds of Canada. National Museums of Canada Revised Edition RWED Library Call #QL685.G6 - B004 Return

Threats

  • Carrière, S. (2000) Pers. communication. Ecosystem Management Biologist; RWED - H126 Return