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Home/Species/ Northern Saw-whet Owl

Aegolius acadicus

(Gmelin, 1788)

Northern Saw-whet Owl

G5Secure Found in 190 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
Least concernIUCN
Northern Saw-whet Owl (Aegolius acadicus). © Simon Tolzmann; Cornell Lab of Ornithology | Macaulay Library.
© Simon Tolzmann; Cornell Lab of Ornithology | Macaulay Library
Northern Saw-whet Owl (Aegolius acadicus). © Devin Pitts; Cornell Lab of Ornithology | Macaulay Library.
© Devin Pitts; Cornell Lab of Ornithology | Macaulay Library
Northern Saw-whet Owl (Aegolius acadicus). © Harris Stein; Cornell Lab of Ornithology | Macaulay Library.
© Harris Stein; Cornell Lab of Ornithology | Macaulay Library
Northern Saw-whet Owl (Aegolius acadicus). © Kaleb Anderson; Cornell Lab of Ornithology | Macaulay Library.
© Kaleb Anderson; Cornell Lab of Ornithology | Macaulay Library
Northern Saw-whet Owl (Aegolius acadicus). © Ethan Denton; Cornell Lab of Ornithology | Macaulay Library.
© Ethan Denton; Cornell Lab of Ornithology | Macaulay Library
Northern Saw-whet Owl (Aegolius acadicus). © Matt Zuro; Cornell Lab of Ornithology | Macaulay Library.
© Matt Zuro; Cornell Lab of Ornithology | Macaulay Library
Northern Saw-whet Owl (Aegolius acadicus). Photo by U.S. Fish & Wildlife Service, Public Domain (U.S. Government Work), via ECOS.
U.S. Fish & Wildlife Service, https://www.usa.gov/government-works
Identity
Unique IDELEMENT_GLOBAL.2.106412
Element CodeABNSB15020
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVertebrate Animal
IUCNLeast concern
CITESAppendix II
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomAnimalia
PhylumCraniata
ClassAves
OrderStrigiformes
FamilyStrigidae
GenusAegolius
COSEWICPS:T
Other Common Names
northern saw-whet owl (EN) Petite nyctale (FR) Tecolote Afilador (ES)
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/.
Taxonomic Comments
Constitutes a superspecies with and may be conspecific with Middle American A.ridgwayi (AOU 1998).
Conservation Status
Rank MethodExpertise without calculation
Review Date2016-04-06
Change Date1996-11-27
Range Extent Comments
BREEDS: southern Alaska to central Saskatchewan and northern New Brunswick, south to southern California, southern Arizona, southern Mexico, western Texas, Missouri, southern Michigan, Maryland; also in Great Smoky Mountains. WINTERS: generally throughout breeding range (some southward withdrawal), irregularly or casually south to southern U.S.
Ecology & Habitat

Habitat

Dense coniferous or mixed forest, cedar groves, alder thickets, swamps, and tamarack bogs; also, when not breeding, in dense second growth, brushy areas, arid scrub, and open buildings. Often roosts in dense evergreens in winter, at various heights and usually close to the trunk (Swengel and Swengel 1992a). Nests usually in old woodpecker hole, also in other tree cavity, or in nest box. Roosts during daylight in or near nest hole during breeding season (NGS 1983). Suitable holes have diameter of 7 cm or more.

Ecology

Studies of a few birds yielded seasonal home range estimates of about 75-150 ha. Two breeding males had home ranges of 142 and 159 hectares (Cannings 1987). Limited data on breeding density suggests maximum of a few pairs per sq km (Johnsgard 1988); singing males can be as close as about 250 meters apart (Swengel 1990). However, most breeding habitat probably supports a maximum of about 1 pair/square kilometer, often much less (Cannings 1993).

Reproduction

Nesting March-July (mainly April-May) in northeastern U.S. and southeastern Canada. Clutch size usually is about 5-6. Incubation, by female, lasts 26-28 days. Young first fly at 4-5 weeks (Johnsgard 1988).
Terrestrial Habitats
Forest - ConiferForest - Mixed
Other Nations (2)
CanadaN5B,N5N
ProvinceRankNative
British ColumbiaS5B,S5NYes
Prince Edward IslandS4BYes
SaskatchewanS5B,S4NYes
New BrunswickS5BYes
Yukon TerritoryS1BYes
AlbertaS5B,SUNYes
QuebecS4BYes
OntarioS5Yes
ManitobaS4BYes
Nova ScotiaS4B,SUMYes
Island of NewfoundlandS3BYes
United StatesN5B,N5N
ProvinceRankNative
IndianaSHBYes
North CarolinaS2B,S2NYes
KansasSNAYes
MarylandS1BYes
WashingtonS4B,S4NYes
MassachusettsS3B,S5NYes
ArkansasSNAYes
GeorgiaS3Yes
NevadaS4Yes
New MexicoS4B,S4NYes
New JerseySU,S4NYes
MichiganS3Yes
UtahS3Yes
North DakotaSNAYes
New HampshireS4Yes
VermontS3B,S3NYes
WisconsinS4B,S4NYes
ConnecticutS2BYes
PennsylvaniaS3B,S4N,S3MYes
TennesseeS1Yes
MinnesotaSNRB,SNRNYes
IdahoS4Yes
ColoradoS5Yes
West VirginiaS2B,S2NYes
South CarolinaS2Yes
MaineS4N,S5BYes
New YorkS3Yes
Navajo NationSNRYes
South DakotaS2B,SNRNYes
Rhode IslandS1B,S1NYes
District of ColumbiaS1NYes
IllinoisS1Yes
NebraskaS3Yes
MontanaS4Yes
AlabamaS2NYes
OregonS4Yes
ArizonaS4Yes
DelawareS1NYes
CaliforniaSNRYes
KentuckySNAYes
AlaskaS3Yes
VirginiaS1B,S2NYes
IowaSNAYes
WyomingS4Yes
Roadless Areas (190)
Alaska (3)
AreaForestAcres
Kenai LakeChugach National Forest213,172
Kenai MountainsChugach National Forest306,600
ResurrectionChugach National Forest224,615
Arizona (4)
AreaForestAcres
Butterfly Roadless AreaCoronado National Forest42,296
Catalina St. Pk. Roadless AreaCoronado National Forest951
Cdo WsaCoronado National Forest1,955
GaliuroCoronado National Forest28,333
California (14)
AreaForestAcres
Black Mtn.Sequoia National Forest15,102
Caples CreekEldorado National Forest17,854
Cutca ValleyCleveland National Forest14,530
Dennison PeakSequoia National Forest6,293
Dinkey LakesSierra National Forest34,171
Fisher Gulch BShasta-Trinity National Forest4,791
Hixon FlatSan Bernardino National Forest8,095
Lake EleanorShasta-Trinity National Forest397
Little French CShasta-Trinity National Forest11,529
MayfieldLassen National Forest14,444
MosesSequoia National Forest22,077
North Fork Middle Fork American RiverTahoe National Forest11,245
Slate Mtn.Sequoia National Forest12,299
SugarloafSan Bernardino National Forest8,206
Colorado (2)
AreaForestAcres
Dome PeakRoutt NF35,716
Long ParkRoutt NF42,100
Georgia (2)
AreaForestAcres
Big MountainChattahoochee National Forest1,974
Big MountainChattahoochee National Forest1,974
Idaho (2)
AreaForestAcres
Pioneer MountainsSawtooth National Forest119,563
Pioneer MountainsSalmon-Challis National Forest172,460
Montana (6)
AreaForestAcres
Bear - Marshall - Scapegoat - SwanLewis and Clark National Forest344,022
Bear - Marshall - Scapegoat - SwanLolo National Forest118,485
Buckhorn Ridge (MT)Kootenai National Forest34,716
FleecerBeaverhead-Deerlodge National Forest31,585
Jerico MountainHelena National Forest8,445
North AbsarokaCuster National Forest21,063
Nevada (5)
AreaForestAcres
Alta T - NorthHumboldt-Toiyabe National Forest9,325
Ruby - Lamoille CynHumboldt-Toiyabe National Forest32,771
Table Mtn. - EastHumboldt-Toiyabe National Forest87,789
Toiyabe RangeHumboldt-Toiyabe National Forest99,225
Ward MountainHumboldt-Toiyabe National Forest15,927
New Hampshire (5)
AreaForestAcres
Great Gulf Ext.White Mountain National Forest15,110
KilkennyWhite Mountain National Forest28,766
Kinsman MountainWhite Mountain National Forest8,999
PemigewassetWhite Mountain National Forest32,255
Pemigewasset ExtWhite Mountain National Forest15,840
New Mexico (2)
AreaForestAcres
Latir PeakCarson National Forest3,573
Meadow CreekGila National Forest34,167
North Carolina (30)
AreaForestAcres
Balsam ConePisgah National Forest10,591
Balsam ConePisgah National Forest10,591
BearwallowPisgah National Forest4,113
BearwallowPisgah National Forest4,113
Big Indian (addition)Nantahala National Forest1,155
Big Indian (addition)Nantahala National Forest1,155
Craggy MountainPisgah National Forest2,657
Craggy MountainPisgah National Forest2,657
Graveyard Ridge (addition)Pisgah National Forest1,958
Graveyard Ridge (addition)Pisgah National Forest1,958
Harper CreekPisgah National Forest7,325
Harper CreekPisgah National Forest7,325
Harper CreekPisgah National Forest7,325
Jarrett CreekPisgah National Forest7,485
Jarrett CreekPisgah National Forest7,485
Laurel MountainPisgah National Forest5,683
Laurel MountainPisgah National Forest5,683
Little Indian (addition)Nantahala National Forest640
Little Indian (addition)Nantahala National Forest640
Lost CovePisgah National Forest5,944
Middle Prong AdditionPisgah National Forest1,852
Middle Prong AdditionPisgah National Forest1,852
Sam Knob (addition)Pisgah National Forest2,576
Sam Knob (addition)Pisgah National Forest2,576
Slide HollowPisgah National Forest193
Slide HollowPisgah National Forest193
South Mills RiverPisgah National Forest8,588
South Mills RiverPisgah National Forest8,588
Wilson CreekPisgah National Forest4,863
Wilson CreekPisgah National Forest4,863
Oregon (7)
AreaForestAcres
Crane MountainFremont National Forest23,096
Hanan TrailFremont National Forest8,111
HellholeUmatilla National Forest65,679
Hurricane CreekWallowa-Whitman National Forest1,606
Maiden PeakDeschutes National Forest26,432
Twin LakesMt. Hood National Forest6,055
WoahinkSiuslaw National Forest5,309
Pennsylvania (6)
AreaForestAcres
Allegheny FrontAllegheny National Forest7,430
Allegheny FrontAllegheny National Forest7,430
CornplanterAllegheny National Forest2,929
Hearts ContentAllegheny National Forest221
Hearts ContentAllegheny National Forest221
Tracy RidgeAllegheny National Forest9,034
South Carolina (2)
AreaForestAcres
Big MountainSumter National Forest2,337
Big MountainSumter National Forest2,337
Tennessee (23)
AreaForestAcres
Bald MountainCherokee National Forest11,743
Bald MountainCherokee National Forest11,743
Big Laurel Branch AdditionCherokee National Forest5,577
Big Laurel Branch AdditionCherokee National Forest5,577
Brushy RidgeCherokee National Forest7,469
Brushy RidgeCherokee National Forest7,469
Brushy RidgeCherokee National Forest7,469
Flint Mill GapCherokee National Forest9,494
Flint Mill GapCherokee National Forest9,494
London Bridge BranchCherokee National Forest3,387
London Bridge BranchCherokee National Forest3,387
Rogers RidgeCherokee National Forest4,738
Rogers RidgeCherokee National Forest4,738
Sampson Mountain AdditionCherokee National Forest3,064
Sampson Mountain AdditionCherokee National Forest3,064
Slide HollowCherokee National Forest4,057
Slide HollowCherokee National Forest4,057
Stone MountainCherokee National Forest5,367
Stone MountainCherokee National Forest5,367
Sycamore CreekCherokee National Forest6,984
Sycamore CreekCherokee National Forest6,984
Sycamore CreekCherokee National Forest6,984
Upper Bald RiverCherokee National Forest9,202
Utah (9)
AreaForestAcres
0401002Ashley National Forest36,113
0401024Ashley National Forest12,882
418006Uinta National Forest11,714
418007Uinta National Forest6,816
418029Uinta National Forest15,673
418043Uinta National Forest9,493
FishhookDixie National Forest12,959
Lewis PeakWasatch-Cache National Forest11,616
Mt. AireWasatch-Cache National Forest9,681
Vermont (1)
AreaForestAcres
Bread LoafGreen Mountain and Finger Lakes National Forests1,768
Virginia (31)
AreaForestAcres
Brush MountainJefferson National Forest6,002
Brush MountainJefferson National Forest6,002
Gum RunGeorge Washington National Forest12,620
Gum RunGeorge Washington National Forest12,620
Laurel ForkGeorge Washington National Forest9,967
Laurel ForkGeorge Washington National Forest9,967
Lewis Fork AdditionJefferson National Forest749
Lewis Fork AdditionJefferson National Forest749
Lewis Fork AdditionJefferson National Forest749
Little Wilson Creek Addition AJefferson National Forest78
Little Wilson Creek Addition AJefferson National Forest78
Little Wilson Creek Addition BJefferson National Forest1,725
Little Wilson Creek Addition BJefferson National Forest1,725
Mountain Lake Addition AJefferson National Forest1,469
Mountain Lake Addition AJefferson National Forest1,469
Mountain Lake Addition B (VA)Jefferson National Forest3,405
Mountain Lake Addition B (VA)Jefferson National Forest3,405
New London Bridge BranchJefferson National Forest844
New London Bridge BranchJefferson National Forest844
Northern MassanuttenGeorge Washington National Forest9,444
Northern MassanuttenGeorge Washington National Forest9,444
Oak KnobGeorge Washington National Forest10,882
Oak KnobGeorge Washington National Forest10,882
Raccoon BranchJefferson National Forest4,388
Raccoon BranchJefferson National Forest4,388
Rogers RunJefferson National Forest181
Rogers RunJefferson National Forest181
Seng MountainJefferson National Forest6,428
Seng MountainJefferson National Forest6,428
SkidmoreGeorge Washington National Forest5,641
SkidmoreGeorge Washington National Forest5,641
Washington (8)
AreaForestAcres
Bald SnowColville National Forest23,198
Big Lava BedGifford Pinchot National Forest19,043
Glacier Peak BMt Baker-Snoqualmie National Forest19,328
Liberty BellOkanogan National Forest108,495
Lion RockWenatchee National Forest4,692
Pasayten RimOkanogan National Forest17,074
SawtoothOkanogan National Forest122,194
South QuinaultOlympic National Forest11,081
West Virginia (26)
AreaForestAcres
Canaan LoopMonongahela National Forest7,867
Canaan LoopMonongahela National Forest7,867
Cranberry AdditionMonongahela National Forest11,123
Cranberry AdditionMonongahela National Forest11,123
Dolly Sods Roaring PlainMonongahela National Forest13,392
Dolly Sods Roaring PlainMonongahela National Forest13,392
Dry ForkMonongahela National Forest657
Dry ForkMonongahela National Forest657
Dry River (WV)George Washington National Forest7,331
Dry River (WV)George Washington National Forest7,331
East Fork Of GreenbrierMonongahela National Forest7,167
East Fork Of GreenbrierMonongahela National Forest7,167
Glady ForkMonongahela National Forest3,239
Glady ForkMonongahela National Forest3,239
Laurel ForkMonongahela National Forest1,172
Laurel ForkMonongahela National Forest1,172
Mcgowan MountainMonongahela National Forest10,504
Mcgowan MountainMonongahela National Forest10,504
Mountain Lake Addition B (WV)Jefferson National Forest557
Mountain Lake Addition B (WV)Jefferson National Forest557
North Mountain HopevilleMonongahela National Forest6,525
North Mountain HopevilleMonongahela National Forest6,525
Tea Creek MountainMonongahela National Forest8,295
Tea Creek MountainMonongahela National Forest8,295
Turkey MountainMonongahela National Forest6,421
Turkey MountainMonongahela National Forest6,421
Wyoming (2)
AreaForestAcres
Grayback RidgeBridger-Teton National Forest295,113
Middle ForkShoshone National Forest51,772
References (35)
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