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Tamiasciurus hudsonicus

(Erxleben, 1777)

North American Red Squirrel

G5Secure Found in 344 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
Least concernIUCN
PSESA Status
Identity
Unique IDELEMENT_GLOBAL.2.1155932
Element CodeAMAFB08040
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVertebrate Animal
IUCNLeast concern
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomAnimalia
PhylumCraniata
ClassMammalia
OrderRodentia
FamilySciuridae
GenusTamiasciurus
USESAPS
Other Common Names
Écureuil roux (FR) Pine Squirrel (EN) red squirrel (EN)
Concept Reference
Hope, A. G., J. L. Malaney, K. C. Bell, F. Salazar-Miralles, A. S. Chavez, B. R. Barber, and J. A. Cook. 2016. Revision of widespread red squirrels (genus: Tamiasciurus) highlights the complexity of speciation within North American forests. Molecular Phylogenetics and Evolution 100:170-182.
Taxonomic Comments
The southwestern population of Tamiasciurus hudsonicus is now recognized as T. fremonti (Hope et al. 2016).

Based on patterns of genetic variation and morphology, Arbogast et al. (2001) suggested that Tamiasciurus should be regarded as comprising one species with three subspecies (hudsonicus, douglasii [including mearnsi], and mogollonensis); mogollonensis represents a southwestern clade that occurs in Arizona, New Mexico, and adjacent parts of southern Colorado and southeastern Utah. Alternatively, Arbogast et al. (2001) suggested that these three taxa might be recognized as separate phylogenetic species. Pending further support for this rearrangement, the North American mammal checklist by Baker et al. (2003) did not accept Arbogast et al.'s (2001) proposed reorganization of Tamiasciurus as a single species. Thorington and Hoffmann (in Wilson and Reeder 2005) also recognized douglasii, hudsonicus, and mearnsi as distinct species.

Earlier, Hall (1981) had suggested that T. douglasii and T. hudsonicus might be conspecific, but Lindsay (1982) concluded that apparent hybrids probably were examples of character convergence.
Conservation Status
Rank MethodExpertise without calculation
Review Date2016-04-05
Change Date1996-11-06
Range Extent>2,500,000 square km (greater than 1,000,000 square miles)
Rank Reasons
Widespread in North America; abundant in many areas.
Range Extent Comments
Alaska to Newfoundland, south to the southern Appalachians and through the Rocky Mountains to Arizona and New Mexico.
Ecology & Habitat

Habitat

Prefers coniferous and mixed forests, but also occurs in deciduous woodlots, hedgerows, second-growth areas. Prefers to nest in tree cavities; also constructs leaf nests and uses ground burrows.

Ecology

Densities range from about 1 per 3.2 ha (Pinaleno Mountains, southeastern Arizona) to 1 per 0.2 ha (Layne 1954, USFWS 1987).

More territorial than most other North Amerian tree squirrels. Some populations in British Columbia are limited by food (acting through effect on reproduction) (Sullivan 1990; see also J. Mamm. 73:930-936); but factors such as territorial behavior may limit populations at high density (Klenner and Krebs 1991, Klenner 1991).

Sciurid mycophagy may play important role in forest ecology (Maser and Maser 1988).

Reproduction

Breeds March-April and June-July in Quebec. Gestation lasts 31-35 days (Lair 1985). Some females produce 2 litters/year; litter size averages 4-5. Some females breed when less than one year old (Lair 1986).
Terrestrial Habitats
Forest - ConiferForest - Mixed
Palustrine Habitats
FORESTED WETLANDRiparian
Other Nations (2)
CanadaN5
ProvinceRankNative
NunavutSUYes
Yukon TerritoryS5Yes
ManitobaS5Yes
AlbertaS5Yes
OntarioS5Yes
Island of NewfoundlandSNANo
Northwest TerritoriesS5Yes
QuebecS5Yes
LabradorS5Yes
Nova ScotiaS5Yes
British ColumbiaS5Yes
Prince Edward IslandS5Yes
SaskatchewanS5Yes
New BrunswickS5Yes
United StatesN5
ProvinceRankNative
MarylandS5Yes
WashingtonS5Yes
MichiganS5Yes
New HampshireS5Yes
VermontS5Yes
UtahS5Yes
PennsylvaniaS5Yes
South DakotaS5Yes
North CarolinaS4Yes
VirginiaS5Yes
IdahoS4Yes
IowaS3Yes
ColoradoS5Yes
Rhode IslandS5Yes
District of ColumbiaSHYes
OhioSNRYes
WyomingS5Yes
North DakotaSNRYes
Navajo NationS5Yes
New JerseyS4Yes
DelawareS3Yes
South CarolinaS3Yes
WisconsinS5Yes
GeorgiaS3Yes
West VirginiaS5Yes
MontanaS5Yes
New YorkS5Yes
IndianaS4Yes
MaineS5Yes
MinnesotaSNRYes
OregonS4Yes
MassachusettsS5Yes
ConnecticutS5Yes
TennesseeS4Yes
IllinoisS3Yes
AlaskaS5Yes
Roadless Areas (344)
Alaska (49)
AreaForestAcres
AnanTongass National Forest36,666
Behm IslandsTongass National Forest4,777
Bering LakeChugach National Forest965,076
Boston BarChugach National Forest53,617
ChichagofTongass National Forest555,858
Chilkat-West Lynn CanalTongass National Forest199,772
Chugach-12Chugach National Forest8,116
Chugach-13Chugach National Forest13,337
College FiordChugach National Forest1,130,818
Copper River WetlandsChugach National Forest85,972
Douglas IslandTongass National Forest28,065
Fidalgo-GravinaChugach National Forest257,968
Freshwater BayTongass National Forest44,933
Game CreekTongass National Forest54,469
GravinaTongass National Forest37,381
Green RocksTongass National Forest11,093
HardingTongass National Forest174,349
Hoonah SoundTongass National Forest79,764
HyderTongass National Forest121,723
Johnson PassChugach National Forest152,508
Juneau UrbanTongass National Forest101,581
Juneau-Skagway IcefieldTongass National Forest1,187,268
Kenai LakeChugach National Forest213,172
Kenai MountainsChugach National Forest306,600
LindenbergTongass National Forest25,855
MadanTongass National Forest68,553
Mansfield PeninsulaTongass National Forest54,991
Middle KruzofTongass National Forest14,724
Nellie JuanChugach National Forest713,697
North BaranofTongass National Forest314,089
North KruzofTongass National Forest33,146
North KupreanofTongass National Forest114,660
North RevillaTongass National Forest215,430
North WrangellTongass National Forest8,091
Pavlof-East PointTongass National Forest5,399
Port AlexanderTongass National Forest120,681
RedoubtTongass National Forest68,347
ResurrectionChugach National Forest224,615
RevillaTongass National Forest29,298
RhineTongass National Forest23,010
Roaded DonutChugach National Forest968
Sheridan GlacierChugach National Forest224,683
Sitka UrbanTongass National Forest112,003
South KruzofTongass National Forest55,193
Taku-SnettishamTongass National Forest664,928
Tenakee RidgeTongass National Forest20,527
Twenty MileChugach National Forest198,775
Upper SitukTongass National Forest16,789
Yakutat ForelandsTongass National Forest323,648
Colorado (3)
AreaForestAcres
Comanche Peak Adjacent AreaArapaho & Roosevelt NFs44,158
Dome PeakRoutt NF35,716
Long ParkRoutt NF42,100
Georgia (1)
AreaForestAcres
Joe GapChattahoochee National Forest5,321
Idaho (14)
AreaForestAcres
Bear CreekCaribou-Targhee National Forest118,582
Bighorn - WeitasNez Perce-Clearwater National Forest254,845
Boulder - White CloudsSawtooth National Forest322,653
Boulder - White CloudsSalmon-Challis National Forest139,297
HoodooNez Perce-Clearwater National Forest153,868
Italian PeakCaribou-Targhee National Forest141,158
Lemhi RangeSalmon-Challis National Forest308,533
NeedlesPayette National Forest131,279
North Lochsa SlopeNez Perce-Clearwater National Forest117,662
PalisadesCaribou-Targhee National Forest122,002
Peace RockBoise National Forest191,734
Pioneer MountainsSalmon-Challis National Forest172,460
Pioneer MountainsSawtooth National Forest119,563
SeceshPayette National Forest248,088
Minnesota (8)
AreaForestAcres
Baker - Homer - Brule LakesSuperior National Forest6,712
Brule Lake - Eagle MountainSuperior National Forest12,380
Cabin CreekSuperior National Forest6,071
Hegman LakesSuperior National Forest675
Kawishiwi Lake To SawbillSuperior National Forest15,305
Little Indian SiouxSuperior National Forest996
Phantom LakeSuperior National Forest6,521
South Kawishiwi RiverSuperior National Forest136
Montana (72)
AreaForestAcres
Allan Mountain (01946)Bitterroot National Forest104,184
Anaconda HillHelena National Forest18,546
Anderson MountainBeaverhead-Deerlodge National Forest31,501
Bear - Marshall - Scapegoat - SwanLewis and Clark National Forest344,022
Bear - Marshall - Scapegoat - SwanHelena National Forest51,360
Bear - Marshall - Scapegoat - SwanLolo National Forest118,485
BeartoothCuster National Forest1,142
BeartoothGallatin National Forest5,285
Big BaldyLewis and Clark National Forest43,135
Big Snowy Mountains WsaLewis and Clark National Forest88,003
Bmss Ra 1485Flathead National Forest334,275
BridgerGallatin National Forest45,059
Buckhorn Ridge (MT)Kootenai National Forest34,716
Burnt MountainCuster National Forest10,698
Cabin Creek Wildlife Management Area OcdGallatin National Forest35,048
Cabinet Face East #671Kootenai National Forest50,326
Chico PeakGallatin National Forest10,744
Clear CreekLolo National Forest5,538
Coal Ridge Ra 1127Flathead National Forest15,429
Crazy MountainGallatin National Forest82,093
Cube Iron - SilcoxLolo National Forest36,998
Deadhorse Ridge Ra 1128Flathead National Forest23,648
East PioneerBeaverhead-Deerlodge National Forest145,082
ElkhornHelena National Forest75,468
Fishtail SaddlebackCuster National Forest16,359
Flagstaff Mountain #690Kootenai National Forest11,114
Freezeout MountainBeaverhead-Deerlodge National Forest97,305
Gallatin FringeGallatin National Forest51,571
Grassy MountainHelena National Forest6,740
HoodooLolo National Forest105,162
Hyalite - Porcupine - Buffalo Horn Wilderness Study AreaGallatin National Forest143,991
Italian PeakBeaverhead-Deerlodge National Forest90,401
Jerico MountainHelena National Forest8,445
Lazyman GulchHelena National Forest11,614
Lebeau RA 1507Flathead National Forest5,450
Line Creek PlateauCuster National Forest24,825
LionheadGallatin National Forest33,549
Lolo CreekLolo National Forest14,335
MadisonGallatin National Forest127,859
Marston Face # 172Kootenai National Forest9,098
Meadow Creek - Upper North ForkLolo National Forest6,906
Middle Fork Judith WsaLewis and Clark National Forest81,131
Middle Mtn. / Tobacco RootsBeaverhead-Deerlodge National Forest96,487
Mt. Gmt Area HCuster National Forest1,335
Mt. Hefty Ra 1481Flathead National Forest12,938
Mt. Henry #666Kootenai National Forest13,603
North AbsarokaCuster National Forest21,063
North AbsarokaGallatin National Forest159,075
North Big HoleBeaverhead-Deerlodge National Forest52,227
Northwest PeaksKootenai National Forest15,358
Patricks Knob - North CutoffLolo National Forest16,970
Pilgrim CreekLewis and Clark National Forest44,608
Proposed Line Creek PrnaCuster National Forest389
QuiggLolo National Forest67,267
Red Lodge Creek HellroaringCuster National Forest17,210
ReefGallatin National Forest2,500
Republic MountainGallatin National Forest836
SapphireBitterroot National Forest43,303
SapphiresBeaverhead-Deerlodge National Forest66,619
Scotchman Peaks (MT)Kootenai National Forest53,909
Selway - Bitterroot (01067)Bitterroot National Forest114,953
Sheep Mountain - StatelineLolo National Forest37,844
Silver KingLolo National Forest12,816
Silver KingBeaverhead-Deerlodge National Forest64,289
South Siegel - South CutoffLolo National Forest13,474
Standard Peak Ra 1129Flathead National Forest8,262
Storm LakeBeaverhead-Deerlodge National Forest9,324
Tash PeakBeaverhead-Deerlodge National Forest61,312
West Big HoleBeaverhead-Deerlodge National Forest133,563
West Fork Yaak #694Kootenai National Forest8,237
West PioneerBeaverhead-Deerlodge National Forest248,631
Willard Estelle #173Kootenai National Forest3,714
New Hampshire (15)
AreaForestAcres
Carr MountainWhite Mountain National Forest17,110
Cherry MountainWhite Mountain National Forest8,766
Dartmouth RangeWhite Mountain National Forest9,233
Great Gulf Ext.White Mountain National Forest15,110
JobildunkWhite Mountain National Forest3,660
KearsargeWhite Mountain National Forest4,554
KilkennyWhite Mountain National Forest28,766
Kinsman MountainWhite Mountain National Forest8,999
Mt. Wolf - Gordon PondWhite Mountain National Forest11,846
PemigewassetWhite Mountain National Forest32,255
Pemigewasset ExtWhite Mountain National Forest15,840
Presidential - Dry River ExtWhite Mountain National Forest10,555
Sandwich RangeWhite Mountain National Forest16,797
WatervilleWhite Mountain National Forest4,312
Wild RiverWhite Mountain National Forest46,878
North Carolina (9)
AreaForestAcres
Bald MountainPisgah National Forest11,085
Balsam ConePisgah National Forest10,591
BearwallowPisgah National Forest4,113
Craggy MountainPisgah National Forest2,657
Graveyard Ridge (addition)Pisgah National Forest1,958
Jarrett CreekPisgah National Forest7,485
Laurel MountainPisgah National Forest5,683
Sam Knob (addition)Pisgah National Forest2,576
Wilson CreekPisgah National Forest4,863
North Dakota (1)
AreaForestAcres
SheyenneDakota Prairie Grasslands14,537
Oregon (19)
AreaForestAcres
Boulder ParkWallowa-Whitman National Forest12,141
Castle RidgeWallowa-Whitman National Forest8,377
Dunns BluffWallowa-Whitman National Forest718
Glacier MountainMalheur National Forest20,661
Greenhorn MountainMalheur National Forest15,936
Greenhorn Mtn.Umatilla National Forest11,191
HellholeUmatilla National Forest65,679
HomesteadWallowa-Whitman National Forest5,817
Hurricane CreekWallowa-Whitman National Forest1,606
Imnaha FaceWallowa-Whitman National Forest29,575
Jaussaud CorralUmatilla National Forest5,535
Lake ForkWallowa-Whitman National Forest21,936
Little SheepWallowa-Whitman National Forest5,238
Snake RiverWallowa-Whitman National Forest31,229
South Fork - TowerUmatilla National Forest16,570
Twin MountainWallowa-Whitman National Forest58,533
Upper Catherine CreekWallowa-Whitman National Forest6,446
Upper Grande RondeWallowa-Whitman National Forest11,723
Walla Walla RiverUmatilla National Forest34,416
South Dakota (1)
AreaForestAcres
Indian CreekBuffalo Gap National Grassland24,666
Tennessee (4)
AreaForestAcres
Bald MountainCherokee National Forest11,743
Beaver Dam CreekCherokee National Forest5,070
Sampson Mountain AdditionCherokee National Forest3,064
Sycamore CreekCherokee National Forest6,984
Texas (1)
AreaForestAcres
Big CreekNational Forests in Texas1,447
Utah (59)
AreaForestAcres
0401001Ashley National Forest11,705
0401002Ashley National Forest36,113
0401005Ashley National Forest38,930
0401007Ashley National Forest16,483
0401016Ashley National Forest5,695
0401030Ashley National Forest531
0401031Ashley National Forest7,110
0419020Ashley National Forest355,684
418001Uinta National Forest5,697
418012Uinta National Forest25,758
418013Uinta National Forest14,643
418024Uinta National Forest51,699
418025Uinta National Forest32,698
418028Uinta National Forest34,002
418029Uinta National Forest15,673
418040Uinta National Forest1,702
Boulder Mtn. / Boulder Top / Deer LakeDixie National Forest110,690
Bullion - DelanoFishlake National Forest14,917
Burch CreekWasatch-Cache National Forest6,938
Circleville MountainFishlake National Forest24,142
City CreekFishlake National Forest13,939
Cove CreekFishlake National Forest25,555
East MountainManti-Lasal National Forest30,705
Fishlake MountainFishlake National Forest25,217
GibsonWasatch-Cache National Forest5,350
HancockDixie National Forest9,809
Happy ValleyDixie National Forest14,458
High Uintas (UT)Wasatch-Cache National Forest102,398
Hog RanchDixie National Forest17,130
Jake HollowDixie National Forest15,146
LakesWasatch-Cache National Forest121,967
Lava BedsDixie National Forest14,944
Lewis PeakWasatch-Cache National Forest11,616
Lone Peak ContiguousWasatch-Cache National Forest874
Long Neck Mesa / Steep Creek / Oak Creek - Steep Creek / OakDixie National Forest55,489
Mahogany RangeWasatch-Cache National Forest11,409
Mcgath Lake - Auger HoleDixie National Forest8,334
Mollens HollowWasatch-Cache National Forest17,690
Mt. AireWasatch-Cache National Forest9,681
Mt. Logan NorthWasatch-Cache National Forest18,930
Mt. Logan SouthWasatch-Cache National Forest17,014
Mt. Logan WestWasatch-Cache National Forest5,285
Mt. NaomiWasatch-Cache National Forest41,922
Mt. OlympusWasatch-Cache National Forest9,982
NoblettsWasatch-Cache National Forest3,116
North FrancisWasatch-Cache National Forest8,148
Pine Valley MountainsDixie National Forest57,673
Public GroveWasatch-Cache National Forest6,341
Right Hand Fork LoganWasatch-Cache National Forest15,023
South FrancisWasatch-Cache National Forest3,374
Stump CreekCaribou National Forest355
Swan Creek MountainWasatch-Cache National Forest9,390
Table Cliffs - Henderson CanyonDixie National Forest19,581
Temple PeakWasatch-Cache National Forest24,081
Tushar MountainFishlake National Forest39,992
Twin PeaksWasatch-Cache National Forest6,157
Upper South ForkWasatch-Cache National Forest16,811
WellsvilleWasatch-Cache National Forest1,717
White PineWasatch-Cache National Forest1,942
Vermont (3)
AreaForestAcres
Bread LoafGreen Mountain and Finger Lakes National Forests1,768
Wilder Mountain 09082Green Mountain and Finger Lakes National Forests8,759
Woodford 09086Green Mountain and Finger Lakes National Forests2,456
Virginia (6)
AreaForestAcres
Beards MountainGeorge Washington National Forest7,505
Beaver Dam CreekJefferson National Forest1,135
Laurel ForkGeorge Washington National Forest9,967
Little Wilson Creek Addition BJefferson National Forest1,725
Saint Marys AdditionGeorge Washington National Forest1,454
Seng MountainJefferson National Forest6,428
Washington (22)
AreaForestAcres
Bald SnowColville National Forest23,198
Black CanyonOkanogan National Forest9,681
ChelanWenatchee National Forest74,650
Cougar MountainColville National Forest4,525
Granite MountainOkanogan National Forest27,428
Grassy TopColville National Forest10,302
Grassy TopIdaho Panhandle National Forests13,485
Harvey CreekColville National Forest10,140
HoodooColville National Forest7,142
Hungry RidgeOkanogan National Forest8,708
Jackson CreekOkanogan National Forest7,791
Liberty BellOkanogan National Forest108,495
Long SwampOkanogan National Forest66,344
Mt. BonaparteOkanogan National Forest10,891
Pasayten RimOkanogan National Forest17,074
ProfanityColville National Forest28,944
Salmo - Priest BColville National Forest11,869
SawtoothOkanogan National Forest122,194
South RidgeOkanogan National Forest6,151
TiffanyOkanogan National Forest22,045
Twin SistersColville National Forest13,051
Willow SpringsUmatilla National Forest10,414
West Virginia (10)
AreaForestAcres
Canaan LoopMonongahela National Forest7,867
Cranberry AdditionMonongahela National Forest11,123
Cranberry Glades Botanical AreaMonongahela National Forest785
Dolly Sods Roaring PlainMonongahela National Forest13,392
Falls Of Hills CreekMonongahela National Forest6,925
Little MountainMonongahela National Forest8,172
Mcgowan MountainMonongahela National Forest10,504
Middle MountainMonongahela National Forest19,020
Seneca CreekMonongahela National Forest22,287
Spice RunMonongahela National Forest6,251
Wisconsin (3)
AreaForestAcres
09012 - Round Lake Study AreaChequamegon-Nicolet National Forest3,707
09162 - MooseChequamegon-Nicolet National Forest6,161
09164 - Tea LakeChequamegon-Nicolet National Forest5,510
Wyoming (44)
AreaForestAcres
Bear RocksBighorn National Forest25,023
Beartooth Proposed WildernessShoshone National Forest16,837
Canyon CreekShoshone National Forest7,530
Cloud Peak ContiguousBighorn National Forest113,757
Devils CanyonBighorn National Forest37,416
French CreekMedicine Bow-Routt National Forest5,928
Grayback RidgeBridger-Teton National Forest295,113
Grommund CreekBighorn National Forest12,089
Gros Ventre MountainsBridger-Teton National Forest106,418
Headwaters Sunlight CreekShoshone National Forest6,016
Horse Creek MesaBighorn National Forest77,808
Labonte CanyonMedicine Bow-Routt National Forest16,281
Leigh CreekBighorn National Forest19,180
Libby FlatsMedicine Bow-Routt National Forest11,107
Little BighornBighorn National Forest133,949
Middle ForkShoshone National Forest51,772
Middle ForkMedicine Bow-Routt National Forest13,238
Mosquito Lake - Seven LakesBridger-Teton National Forest51,950
Mowry PeakMedicine Bow-Routt National Forest6,244
Pacific Creek - Blackrock CreekBridger-Teton National Forest24,658
PalisadesTarghee National Forest1,121
Pass CreekShoshone National Forest6,172
Phillips RidgeBridger-Teton National Forest10,108
Piney CreekBighorn National Forest22,240
ReefShoshone National Forest16,817
Rock CreekBighorn National Forest48,657
Salt River RangeBridger-Teton National Forest235,661
Sand CreekBlack Hills National Forest7,950
Sibley LakeBighorn National Forest10,367
Sleeping GiantShoshone National Forest5,176
Snowy RangeMedicine Bow-Routt National Forest29,660
South Beartooth HighwayShoshone National Forest105,570
Spread Creek - Gros Ventre RiverBridger-Teton National Forest166,097
Sulphur CreekShoshone National Forest30,221
Teton Corridor TrailheadsBridger-Teton National Forest286
Togwotee PassShoshone National Forest7,344
Walker PrairieBighorn National Forest62,434
Wapiti Valley NorthShoshone National Forest18,345
Wapiti Valley SouthShoshone National Forest43,517
West DunoirShoshone National Forest2,542
West Slope TetonsTarghee National Forest47,448
West Slope WindsBridger-Teton National Forest143,252
Wilderness Study AreaTarghee National Forest51,961
Windy MountainShoshone National Forest31,283
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