Megascops kennicottii - (Elliot, 1867)
Western Screech-Owl
Synonym(s): Otus kennicottii (Elliot, 1867)
Taxonomic Status: Accepted
Related ITIS Name(s): Megascops kennicottii (Elliot, 1867) (TSN 686659)
French Common Names: petit-duc des montagnes
Spanish Common Names: Tecolote Occidental
Unique Identifier: ELEMENT_GLOBAL.2.103456
Element Code: ABNSB01040
Informal Taxonomy: Animals, Vertebrates - Birds - Other Birds
 
Kingdom Phylum Class Order Family Genus
Animalia Craniata Aves Strigiformes Strigidae Megascops
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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: Otus kennicottii
Taxonomic Comments: Formerly treated as a subgenus within Otus (Marshall and King in Amadon and Bull 1988), but mitochondrial DNA and vocal differences with Old World species indicate that generic status is warranted (Konig et al. 1999).

Prior to 1982 regarded as conspecific with O. ASIO. Populations in northwestern Mexico have been treated as separate species (O. VINACEUS) by some authors. Mixed pairs and overlap of ASIO and KENNICOTTII in Colorado and Texas is attributed to long-distance dispersal in marginally poor habitat. Sympatry without interbreeding with ASIO reported for western Edwards Plateau (Dixon 1989).
Conservation Status
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NatureServe Status

Global Status: G4G5
Global Status Last Reviewed: 09Apr2016
Global Status Last Changed: 09Apr2016
Ranking Methodology Used: Ranked by inspection
Rounded Global Status: G4 - Apparently Secure
Reasons: Still widespread; population probably stable in many areas, probably declining in others. Threatened by habitat loss and/or degradation, particularly the loss of riparian forests and woodlands.
Nation: United States
National Status: N5 (05Jan1997)
Nation: Canada
National Status: N4 (08Jan2018)

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 (S2), Arizona (S5), California (SNR), Colorado (S4B), Idaho (S1), Kansas (S1), Montana (S3S4), Navajo Nation (S3S4), Nevada (S4), New Mexico (S4B,S4N), Oklahoma (S2), Oregon (S4?), Texas (S4B), Utah (S3S4), Washington (S4), Wyoming (S2)
Canada British Columbia (S4), Saskatchewan (S1B,S1N)

Other Statuses

Implied Status under the Committee on the Status of Endangered Wildlife in Canada (COSEWIC):T
Comments on COSEWIC: The species was considered a single unit and placed in the Data Deficient category in April 1995. Re-examined in May 2002 and split into two groups according to subspecies. The kennicottii subspecies was designated Special Concern and the macfarlanei subspecies was designated Endangered in May 2002. The original designation was de-activated.
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: 20,000-2,500,000 square km (about 8000-1,000,000 square miles)
Range Extent Comments: RESIDENT: from south-coastal and southeastern Alaska, coastal and southern British Columbia, northern Idaho, western Montana, southeastern Colorado and extreme western Oklahoma south to southern Baja California, northern Sinaloa, in Mexican highlands to Distrito Federal, and to western Texas (AOU 1998, Cannings and Angell 2001). Apparently has expanded north into southern Alberta.

Number of Occurrences: 81 to >300

Population Size: 10,000 - 1,000,000 individuals
Population Size Comments: Canadian population estimated at 3000-10,000 individuals (Chaundy-Smart 2002); many more than this occur elsewhere in the range.

Overall Threat Impact: High
Overall Threat Impact Comments: Primary threat is loss or degradation of habitat. Closely linked to riparian forests and woodlands over much of its range, and this is often the first habitat in any given area to be altered, especially in the dry southwest (Cannings and Angell 2001). On coastal British Columbia, may be threatened by largescale logging (Chaundy-Smart 2002). In the Pacific Northwest, traditional territories have been abandoned coincident with the arrival of Barred Owls in an area (Cannings and Angell 2001).

Short-term Trend: Decline of <30% to relatively stable
Short-term Trend Comments: No rangewide data, but probably declining slowly as habitat declines (Cannings and Angell 2001). Definite declines have been noted in the more developed parts of southwestern British Columbia (Chaundy-Smart 2002).

Other NatureServe Conservation Status Information

Distribution
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Global Range: (20,000-2,500,000 square km (about 8000-1,000,000 square miles)) RESIDENT: from south-coastal and southeastern Alaska, coastal and southern British Columbia, northern Idaho, western Montana, southeastern Colorado and extreme western Oklahoma south to southern Baja California, northern Sinaloa, in Mexican highlands to Distrito Federal, and to western Texas (AOU 1998, Cannings and Angell 2001). Apparently has expanded north into southern Alberta.

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, AZ, CA, CO, ID, KS, MT, NM, NN, NV, OK, OR, TX, UT, WA, WY
Canada BC, SK

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: NatureServe, 2002; WILDSPACETM 2002


U.S. Distribution by County Help
State County Name (FIPS Code)
AZ Navajo (04017)
ID Ada (16001), Adams (16003), Bingham (16011), Blaine (16013), Boise (16015), Bonner (16017), Boundary (16021), Canyon (16027), Caribou (16029), Cassia (16031), Elmore (16039), Gem (16045), Gooding (16047), Idaho (16049), Jefferson (16051), Jerome (16053), Latah (16057), Lemhi (16059), Madison (16065), Nez Perce (16069), Owyhee (16073), Twin Falls (16083), Washington (16087)
NV Esmeralda (32009)
WY Big Horn (56003), Converse (56009), Fremont (56013), Goshen (56015), Hot Springs (56017), Johnson (56019), Lincoln (56023), Natrona (56025), Sheridan (56033), Sublette (56035), Sweetwater (56037), Teton (56039), Uinta (56041)
* Extirpated/possibly extirpated
U.S. Distribution by Watershed Help
Watershed Region Help Watershed Name (Watershed Code)
10 Lower Wind (10080005)+, Upper Bighorn (10080007)+, Nowood (10080008)+, Greybull (10080009)+, Big Horn Lake (10080010)+, Dry (10080011)+, Upper Tongue (10090101)+, Clear (10090206)+, Niobrara Headwaters (10150002)+, Middle North Platte-Casper (10180007)+, Glendo Reservoir (10180008)+, Middle North Platte-Scotts Bluff (10180009)+
14 Upper Green (14040101)+, New Fork (14040102)+, Bitter (14040105)+, Upper Green-Flaming Gorge Reservoir (14040106)+, Blacks Fork (14040107)+
15 Moenkopi Wash (15020018)+
16 Ralston-Stone Cabin Valleys (16060011)+
17 Lower Kootenai (17010104)+, Moyie (17010105)+, Priest (17010215)+, Snake headwaters (17040101)+, Gros Ventre (17040102)+, Greys-Hobock (17040103)+, Idaho Falls (17040201)+, American Falls (17040206)+, Blackfoot (17040207)+, Raft (17040210)+, Goose (17040211)+, Upper Snake-Rock (17040212)+, Salmon Falls (17040213)+, Beaver-Camas (17040214)+, Big Wood (17040219)+, Bruneau (17050102)+, Middle Snake-Succor (17050103)+, Boise-Mores (17050112)+, South Fork Boise (17050113)+, Lower Boise (17050114)+, Middle Snake-Payette (17050115)+, Payette (17050122)+, Weiser (17050124)+, Brownlee Reservoir (17050201)+, Hells Canyon (17060101)+, Lower Snake-Asotin (17060103)+, Palouse (17060108)+, Lemhi (17060204)+, Middle Salmon-Chamberlain (17060207)+, South Fork Salmon (17060208)+, Lower Salmon (17060209)+, Little Salmon (17060210)+, Lower Selway (17060302)+
+ Natural heritage record(s) exist for this watershed
* Extirpated/possibly extirpated
Ecology & Life History
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Basic Description: A small owl.
Reproduction Comments: Clutch size averages 3-4. Incubation about 26 days.
Ecology Comments: In central Idaho, home ranges of 2 radio-tagged birds reported as 3-9 ha and 29-58 ha based on 75% and 95% contour intervals, respectively. Distance between adjacent pairs ranges from ca. 50 up to a few hundred meters (see Johnsgard 1988).
Non-Migrant: Y
Locally Migrant: N
Long Distance Migrant: N
Mobility and Migration Comments: In Rocky Mountains some individuals may descend to lower elevations or into more protected valleys for winter (Voous and Cameron 1989).
Palustrine Habitat(s): Riparian
Terrestrial Habitat(s): Desert, Forest - Conifer, Forest - Hardwood, Forest - Mixed, Shrubland/chaparral, Suburban/orchard, Woodland - Conifer, Woodland - Hardwood, Woodland - Mixed
Special Habitat Factors: Standing snag/hollow tree
Habitat Comments: Woodland, especially broadleaf (e.g. oak) and riparian woodland, and scrub (Subtropical and Temperate zones) (AOU 1983). Also moist coniferous forest and woodland on northwest coast. Usually found at lower elevations, where in southwest range overlaps with Whiskered Screech-owl (National Geographic Society 1983).

Nests in natural tree cavity or an abandoned woodpecker hole, including holes in saguaro cactus. Readily nest in nest boxes.

Adult Food Habits: Carnivore, Invertivore
Immature Food Habits: Carnivore, Invertivore
Food Comments: Feeds mainly on small mammals (mice and shrews), insects, birds; sometimes also other small vertebrates. Diet may vary seasonally and geographically, depending on local prey abundance.
Adult Phenology: Nocturnal
Immature Phenology: Nocturnal
Length: 22 centimeters
Weight: 186 grams
Economic Attributes Not yet assessed
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Management Summary
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Monitoring Requirements: See Bull (1987) for capture techniques.
Population/Occurrence Delineation
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Group Name: Small and Medium Owls

Use Class: Breeding
Subtype(s): Nest site
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: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Separation distance is not intended to delineate demographically independent populations or metapopulations (such units would be quite large) but rather serves to circumscribe breeding occurrences that are of practical size for conservation/management use.

Separation distance is larger than three times the diameter of an average home range for these volant species; based the diameter of larger home ranges of males, e.g. those of Northern Pygmy-Owls given below.

Ferruginous Pygmy-Owl: post-fledging families used 9.3 to about 60 hectares until the young dispersed (Proudfoot and Johnson 2000).

Northern Pygmy-Owl: territory in Colorado estimated to be about 75 hectares (Rashid 1999, cited in Holt and Petersen 2000); home ranges of breeding males in Washington 170-230 hectares (A. Giese, pers. comm., cited in Holt and Petersen 2000); home ranges of males in Sweden averaged 231 hectares (Kullberg 1995).

Northern Saw-whet Owl: Two breeding males had home ranges of 142 and 159 hectares (Cannings 1987). Most breeding habitat probably supports a maximum of about 1 pair/square kilometer, often much less (Cannings 1993); singing males can be as close as about 250 meters apart (Swengel 1990).

Elf Owl: home ranges smaller, range 0.2-2.6, mean 1.0 hectares (Gamel 1997).

Flammulated Owl males had mean home ranges of about 14 hectares in Colorado (Linkhart 1984) and about 16 hectares in Oregon (during the incubation period; Goggans 1986). DNA data indicate very low differentiation among populations in different mountain ranges in New Mexico and Utah; evidently the species exhibits long-distance natal dispersal and frequent intermountain dispersal (Arsenault et al. 2005).

Whiskered Screech-Owls had home ranges about 1550 meters long, along permanent creek (Gehlbach and Gehlbach 2000).

Burrowing Owl: In Saskatchewan, the average home range was about 1.2 kilometers in diameter (Haug and Oliphant 1990).

Long-eared Owl: In Wyoming, breeding home range in riparian habitat varied from 34-106 hectares and averaged 51 hectares (Craighead and Craighead 1956).

Short-eared Owl: Breeding territories average 64 -74 hectares (Holt 1992, Clark 1975).

Inferred Minimum Extent of Habitat Use (when actual extent is unknown): .6 km
Inferred Minimum Extent Justification: Conservatively based on an average home range of 27 hectares for a Ferruginous Pygmy-Owl family (Proudfoot and Johnson 2000). A breeding male Northern Saw-whet Owl spent most of its active time in a core area of only 27 hectares (Cannings 1987).

Long-eared Owl: May use an IE of 0.8 km, which is the diameter of an average home range (Craighead and Craighead 1956).

Short-eared Owl: May use an IE of 0.9 km, which is based on an average breeding home range of 65 hectares.

Date: 26Feb2005
Author: Cannings, S., and G. Hammerson
Notes: Contains owls in the genera Otus, Glaucidium, Aegolius, Asio and Athene.

Use Class: Nonbreeding
Minimum Criteria for an Occurrence: Evidence of recurring presence of wintering individuals (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: 5 km
Separation Distance for Suitable Habitat: 5 km
Separation Justification: Separation distance larger than three times the diameter of an average home range for these volant species; based the diameter of larger home ranges of males, e.g. those of Northern Pygmy-Owls: in Washington 170-230 hectares (A. Giese, pers. comm., cited in Holt and Petersen 2000); in Sweden, averaged 231 hectares (Kullberg 1995).
Whiskered Screech-Owls had home ranges about 1550 meters long, along permanent creek (Gehlbach and Gehlbach 2000).

Inferred Minimum Extent of Habitat Use (when actual extent is unknown): .6 km
Inferred Minimum Extent Justification: Conservatively based on a home range of 27 hectares; for example, a breeding male Northern Saw-whet Owl spent most of its active time in a 27-hectare core area (Cannings 1987).
Date: 16Apr2002
Author: Cannings, S.

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: 5 km
Separation Distance for Suitable Habitat: 5 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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NatureServe Conservation Status Factors Edition Date: 27Jan2003
NatureServe Conservation Status Factors Author: Cannings, S.
Element Ecology & Life History Edition Date: 30Mar1995
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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Citation for Bird Range Maps of North America:
Ridgely, R.S., T.F. Allnutt, T. Brooks, D.K. McNicol, D.W. Mehlman, B.E. Young, and J.R. Zook. 2003. Digital Distribution Maps of the Birds of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

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"Data provided by NatureServe in collaboration with Robert Ridgely, James Zook, The Nature Conservancy - Migratory Bird Program, Conservation International - CABS, World Wildlife Fund - US, and Environment Canada - WILDSPACE."

Citation for Mammal Range Maps of North America:
Patterson, B.D., G. Ceballos, W. Sechrest, M.F. Tognelli, T. Brooks, L. Luna, P. Ortega, I. Salazar, and B.E. Young. 2003. Digital Distribution Maps of the Mammals of the Western Hemisphere, version 1.0. NatureServe, Arlington, Virginia, USA.

Acknowledgement Statement for Mammal Range Maps of North America:
"Data provided by NatureServe in collaboration with Bruce Patterson, Wes Sechrest, Marcelo Tognelli, Gerardo Ceballos, The Nature Conservancy-Migratory Bird Program, Conservation International-CABS, World Wildlife Fund-US, and Environment Canada-WILDSPACE."

Citation for Amphibian Range Maps of the Western Hemisphere:
IUCN, Conservation International, and NatureServe. 2004. Global Amphibian Assessment. IUCN, Conservation International, and NatureServe, Washington, DC and Arlington, Virginia, USA.

Acknowledgement Statement for Amphibian Range Maps of the Western Hemisphere:
"Data developed as part of the Global Amphibian Assessment and provided by IUCN-World Conservation Union, Conservation International and NatureServe."

NOTE: Full metadata for the Bird Range Maps of North America is available at:
http://www.natureserve.org/library/birdDistributionmapsmetadatav1.pdf.

Full metadata for the Mammal Range Maps of North America is available at:
http://www.natureserve.org/library/mammalsDistributionmetadatav1.pdf.

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