Sciurus carolinensis

Gmelin, 1788

Eastern Gray Squirrel

G5Secure Found in 52 roadless areas NatureServe Explorer →
G5SecureGlobal Rank
Least concernIUCN
Identity
Unique IDELEMENT_GLOBAL.2.104371
Element CodeAMAFB07010
Record TypeSPECIES
ClassificationSpecies
Classification StatusStandard
Name CategoryVertebrate Animal
IUCNLeast concern
Endemicoccurs (regularly, as a native taxon) in multiple nations
KingdomAnimalia
PhylumCraniata
ClassMammalia
OrderRodentia
FamilySciuridae
GenusSciurus
Other Common Names
eastern gray squirrel (EN) Eastern Grey Squirrel (EN) Écureuil gris (FR)
Concept Reference
Wilson, D. E., and D. M. Reeder (editors). 1993. Mammal species of the world: a taxonomic and geographic reference. Second edition. Smithsonian Institution Press, Washington, DC. xviii + 1206 pp. Available online at: http://www.nmnh.si.edu/msw/.
Taxonomic Comments
Under a proposed taxonomic arrangement for Sciurini (de Abreu-Jr et al. 2020a, de Abreu-Jr et al. 2020b), Sciurus carolinensis would be moved to the genus Neosciurus; pending further investigation, this arrangement is tentatively not accepted following the American Society of Mammalogists (2024).
Conservation Status
Rank MethodExpertise without calculation
Review Date2016-04-05
Change Date1996-11-06
Range Extent Comments
Eastern U.S. and adjacent southern Canada; southern Quebec to Manitoba, south to eastern Texas and Florida. Range has been extended through introductions into Quebec, Ontario, New Brunswick, Manitoba, Saskatchewan, British Columbia, Nova Scotia, California, Oregon, Washington, and Montana (Teaford 1986, Koprowski 1994). Introduced also in the British Isles, Italy, South Africa, and Australia (extirpated by 1973) (see Koprowski 1994).
Ecology & Habitat

Habitat

Prefers mature deciduous and mixed forests with abundant supplies of mast (e.g., acorns, hickory nuts). A diversity of nut trees is needed to support high densities. Also uses city parks and floodplains. Seldom far from permanent open water. In southern Alabama, narrow bands of hardwoods along ephemeral streams were an important component of the habitat in even-aged pine and mixed pine-hardwood stands (Fischer and Holler 1991). Rests in tree cavity or leaf nest; leaf nests apparently are made primarily by dispersing juveniles 18-19 weeks old. Nests in tree cavities or in leaf nests, usually 25 feet or more above ground. Most winter-spring litters are born in tree cavities, most spring-summer litters in leaf nests (Teaford 1986). Cavities suitable for nesting are dry, 15-25 cm in diameter, 40-50 cm deep, with an entrance hole about 8 cm in diameter (Teaford 1986). Females may move young from tree cavity nest to leaf nest, possibly to escape fleas.

Ecology

Fall density generally ranges from 0.5 to 14/ha, but 3.2/ha generally is considered high for extensive forested tracts; densities of 21/ha or more may occur in city parks; populations tend to increase after bumper mast crops, decrease if mast crop fails (Teaford 1986). May aggregate at abundant food sources.

Home range averages 0.5-10 ha, with older males tending to have the largest ranges (Teaford 1986); usually home range is less than 5 ha (see Koprowski 1994). Not territorial, home range overlap is extensive; social system is characterized by a linear dominance hierarchy.

Disperses up to a few kilometers from natal area upon approaching sexual maturity. Large-scale one-way emigrations have been observed, generally coinciding with high population density and mast crop failure.

Taken by many predators, but predation does not appear to limit populations (Teaford 1986). Mean annual mortality reported for adults is 42-57% (Koprowski 1994).

Reproduction

In Illinois, most breeding occurs in December-February and May-June; slightly later in more northern latitudes (see Koprowski 1994). One or two litters/year. First litter is produced mostly in February-March, sometimes as early as January in some areas; second litter, July or August. Gestation lasts 44 days. Litter size most often is 2-3. Young are tended by female. Weaning is completed at about 10-12 weeks (in spring and/or late summer-early fall). Most breed as yearlings, sometimes sooner (as early as 5 months) or later. Reproductive output, including the percentage of adults that produce young and the number of litters/year, is positively correlated with mast abundance. Maximum reproductive longevity is about a decade.
Terrestrial Habitats
Forest - HardwoodForest - MixedWoodland - HardwoodWoodland - MixedSuburban/orchard
Palustrine Habitats
Riparian
Other Nations (2)
CanadaN5
ProvinceRankNative
British ColumbiaSNANo
OntarioS5Yes
SaskatchewanSNANo
QuebecS5Yes
AlbertaSNANo
Nova ScotiaSNANo
ManitobaS5Yes
New BrunswickS5Yes
United StatesN5
ProvinceRankNative
MichiganS5Yes
North CarolinaS5Yes
OklahomaSNRYes
IdahoSNANo
TexasS5Yes
ConnecticutS5Yes
KansasS5Yes
MississippiS5Yes
WashingtonSNANo
Rhode IslandS5Yes
NebraskaS4Yes
PennsylvaniaS5Yes
VermontS5Yes
District of ColumbiaS5Yes
New HampshireS5Yes
New YorkS5Yes
FloridaSNRYes
KentuckyS5Yes
DelawareS5Yes
MarylandS5Yes
IowaS5Yes
South DakotaSUYes
WyomingSNANo
MinnesotaSNRYes
South CarolinaS5Yes
OregonSNANo
MaineS5Yes
MissouriS5Yes
AlabamaS5Yes
IndianaS5Yes
MassachusettsS5Yes
VirginiaS5Yes
IllinoisS5Yes
ArkansasS5Yes
GeorgiaS5Yes
MontanaSNANo
OhioSNRYes
North DakotaSNRYes
West VirginiaS5Yes
LouisianaS5Yes
WisconsinS5Yes
New JerseyS5Yes
TennesseeS5Yes
Roadless Areas (52)
Alabama (1)
AreaForestAcres
Blue MountainTalladega National Forest4,986
Arkansas (2)
AreaForestAcres
Gee CreekOzark-St. Francis National Forest7,957
Little BlakelyOuachita National Forest3,342
California (1)
AreaForestAcres
Duncan CanyonTahoe National Forest8,621
Florida (2)
AreaForestAcres
Alexander Springs CreekOcala National Forest2,954
Natural Area WsaOsceola National Forest2,543
Georgia (5)
AreaForestAcres
Indian Grave GapChattahoochee National Forest1,020
Joe GapChattahoochee National Forest5,321
Kelly RidgeChattahoochee National Forest8,325
Lance CreekChattahoochee National Forest9,025
Rocky MountainChattahoochee National Forest4,269
Idaho (2)
AreaForestAcres
Bear CreekCaribou-Targhee National Forest118,582
HoodooNez Perce-Clearwater National Forest153,868
Illinois (1)
AreaForestAcres
Burke BranchShawnee National Forest6,231
New Hampshire (1)
AreaForestAcres
Kinsman MountainWhite Mountain National Forest8,999
North Carolina (12)
AreaForestAcres
Chunky Gal (addition)Nantahala National Forest3,336
Craggy MountainPisgah National Forest2,657
Harper CreekPisgah National Forest7,325
Jarrett CreekPisgah National Forest7,485
Laurel MountainPisgah National Forest5,683
Lost CovePisgah National Forest5,944
Mackey MountainPisgah National Forest5,934
Pocosin AdditionCroatan National Forest286
SnowbirdNantahala National Forest8,489
South Mills RiverPisgah National Forest8,588
Tusquitee BaldNantahala National Forest13,670
Wesser BaldNantahala National Forest4,061
South Dakota (1)
AreaForestAcres
Indian CreekBuffalo Gap National Grassland24,666
Tennessee (4)
AreaForestAcres
Devil's BackboneCherokee National Forest4,287
Flint Mill GapCherokee National Forest9,494
Sampson Mountain AdditionCherokee National Forest3,064
Stone MountainCherokee National Forest5,367
Texas (1)
AreaForestAcres
Big CreekNational Forests in Texas1,447
Vermont (1)
AreaForestAcres
Bread LoafGreen Mountain and Finger Lakes National Forests1,768
Virginia (10)
AreaForestAcres
Adams PeakGeorge Washington National Forest7,135
Beards MountainGeorge Washington National Forest7,505
Brush MountainJefferson National Forest6,002
Gum RunGeorge Washington National Forest12,620
Mountain Lake Addition AJefferson National Forest1,469
New London Bridge BranchJefferson National Forest844
North MountainJefferson National Forest8,377
Northern MassanuttenGeorge Washington National Forest9,444
Seng MountainJefferson National Forest6,428
Southern MassanuttenGeorge Washington National Forest11,985
Washington (3)
AreaForestAcres
Mt. Baker MaMt Baker-Snoqualmie National Forest24,847
Slide RidgeWenatchee National Forest11,430
TeanawayWenatchee National Forest72,849
West Virginia (5)
AreaForestAcres
Dolly Sods Roaring PlainMonongahela National Forest13,392
Little MountainMonongahela National Forest8,172
Mcgowan MountainMonongahela National Forest10,504
Middle MountainMonongahela National Forest19,020
North Mountain HopevilleMonongahela National Forest6,525
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