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Equus caballus

Linnaeus, 1758

Horse

GNANot Applicable Found in 104 roadless areas NatureServe Explorer →

GNANot ApplicableGlobal Rank

Identity

Unique IDELEMENT_GLOBAL.2.103569

Element CodeAMATA01010

Record TypeSPECIES

ClassificationSpecies

Classification StatusStandard

Name CategoryVertebrate Animal

Endemicoccurs (regularly, as a native taxon) in multiple nations

KingdomAnimalia

PhylumCraniata

ClassMammalia

OrderPerissodactyla

FamilyEquidae

GenusEquus

Other Common Names

Caballo (ES) Cheval (FR) Feral Horse (EN)

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

This is the domestic form of Equus ferus. Equus przewalskii has been included in E. caballus by most recent authors. Some authors have proposed that the specific name be changed to ferus because the name caballus was based on domestic animals. Jones et al. (1992) and Grubb (in Wilson and Reeder 1993, 2005) continued to use the name E. caballus (see Grubb, in Wilson and Reeder 2005, for discussion of nomenclature).

Electrophoretic and immunologic analyses indicate the feral herds from 4 eastern U.S. barrier islands apparently are not genetically unique (Goodloe et al. 1991).

Conservation Status

Review Date2003-09-04

Change Date2003-09-04

Range Extent Comments

Native to Eurasia. Domesticated worldwide. Feral in Portugal, Spain, France, Greece, Iran, Sri Lanka, Australia, New Zealand, Colombia, Hispaniola, Canada, U.S., Galapagos, and probably other oceanic islands. Feral in many western U.S. states, mostly in the Great Basin (Nevada, and portions of Oregon, California, and Utah), with large numbers also in the Red Desert of southwestern Wyoming, and smaller populations elsewhere in Wyoming and in Arizona, Colorado, Idaho, Montana, and New Mexico. Free-ranging feral horses occur also on some Atlantic coast barrier islands (Assateague Island, Virginia and Maryland; Shackleford Banks, North Carolina; Carrot Island, North Carolina; Cumberland Island, Georgia). Feral horses on Ocracoke Island, North Carolina are maintained in an enclosure. Formerly feral in Hawaii (see Tomich 1986 and Kramer 1971 for history of horse in Hawaii).

Ecology & Habitat

Habitat

In West, shrubby sagebrush plains and mountains, juniper woodland; ranges include grazing area, shelter, water, and shade (Slade and Godfrey 1982). Often on ridgetops.

Ecology

Common social group: several females led by dominant male; females usually do not change group membership; young males are expelled from group at 1-3 years, form bachelor groups.

Annual home range usually is less than 25 sq km (but up to 300 sq km in Wyoming).

In Montana, annual survival usually was high (93-99%), sometimes as low as 50%; population growth was 18% annually in population maintained by removal at 120-150 (Garrot and Taylor 1990).

In the western U.S., females tend to have greater survivorship than do males early in life, but males tend to be more frequent than are females in the oldest age classes (>10 years) (Garrott 1991).

In the southern Great Basin of Nevada, mountain lion predation on the young was believed to be a major population limiting factor (Greger and Romney 1999).

Reproduction

On Assateague Island, breeding activity peaks in May and June, foaling peaks in April and May; weaning occurs at age 1 year (or 2-3 years if the female does not foal in consecutive years) (Kirkpatrick and Turner 1991). Gestation averages about 340 days. Postpartum estrus occurs 7-11 days after birth. In general, first reproduction by females occurs at age 2 years, and the highest foaling rates occur among females 6-15 years old (Garrott et al. 1991). In Idaho, 36% of the 2-year-olds were pregnant, 85% of 6-15-year-olds; no yearlings were pregnant; at least 50% of the eligible mares were pregnant in consecutive years (Seal and Plotka 1983). In Nevada, Oregon, and Wyoming, about 60-80% of the females two years of age or older were pregnant, as were some yearling females. In Montana, females did not reproduce until 3 years old; annual foaling rate of adult females was 36-56% (Garrot and Taylor 1990). See also Bowling and Touchberry (1990) for information on reproduction of Great Basin horses. Foaling rate was 33% and 63% in two separate herds on Assateague Island, Maryland and Virginia (Kirkpatrick and Turner 1991).

Terrestrial Habitats

Woodland - ConiferShrubland/chaparralGrassland/herbaceous

Other Nations (2)

United StatesNNA

Province	Rank	Native
Maryland	SNA	No
Wyoming	SNA	No
Georgia	SNA	No
Virginia	SNA	No
Rhode Island	SNA	No
Oregon	SNA	No
California	SNA	No
Navajo Nation	SNA	No
Idaho	SNA	No
Arizona	SNA	No
Colorado	SNA	No
New Mexico	SNA	No
Texas	SNA	No
North Carolina	SNA	No
Nevada	SNA	No
Utah	SNA	No
Montana	SNA	No

CanadaNNA

Province	Rank	Native
Nova Scotia	SNA	No
British Columbia	SNA	No
Northwest Territories	SNA	No
Yukon Territory	SNA	No
Alberta	SNA	No
Saskatchewan	SNA	No

Roadless Areas (104)

Arizona (8)

Area	Forest	Acres
Black Cross	Tonto National Forest	5,966
Black River Canyon	Apache-Sitgreaves National Forests	11,817
Boulder	Tonto National Forest	40,359
Burro Canyon	Kaibab National Forest	19,928
Goldfield	Tonto National Forest	15,257
Horse Mesa	Tonto National Forest	9,146
Lime Creek	Tonto National Forest	42,568
Lower Rincon	Coronado National Forest	3,278

California (14)

Area	Forest	Acres
Boundary Peak (CA)	Inyo National Forest	210,884
Dexter Canyon	Inyo National Forest	17,053
Domeland Add.	Sequoia National Forest	3,046
Excelsior (CA)	Inyo National Forest	45,607
Garcia Mountain	Los Padres National Forest	7,850
Glass Mountain	Inyo National Forest	52,867
Iceberg - Mill Creek	Humboldt-Toiyabe National Forest	26,988
Machesna Mountain	Los Padres National Forest	12,271
Mill Creek	Sequoia National Forest	27,643
Mono Craters	Inyo National Forest	7,115
Orleans Mtn. B	Six Rivers National Forest	17,183
Portuguese	Klamath National Forest	18,915
Sherwin	Inyo National Forest	3,140
Woodpecker	Sequoia National Forest	11,936

Montana (4)

Area	Forest	Acres
Bmss Ra 1485	Flathead National Forest	334,275
Italian Peak	Beaverhead-Deerlodge National Forest	90,401
Lost Water Canyon	Custer National Forest	9,251
Lost Water Canyon Rna	Custer National Forest	561

Nevada (47)

Area	Forest	Acres
Alta T - North	Humboldt-Toiyabe National Forest	9,325
Angel Peak North	Humboldt-Toiyabe National Forest	12,577
Angel Peak South	Humboldt-Toiyabe National Forest	6,540
Antelope - West 1	Humboldt-Toiyabe National Forest	8,642
Bald Mtn.	Humboldt-Toiyabe National Forest	41,598
Boundary Peak (NV)	Inyo National Forest	21,851
Butler	Humboldt-Toiyabe National Forest	39,470
Butler Mtn.	Humboldt-Toiyabe National Forest	25,878
Charleston - Carpenter	Humboldt-Toiyabe National Forest	17,828
Charleston - Clark	Humboldt-Toiyabe National Forest	4,674
Charleston - Macks Cyn	Humboldt-Toiyabe National Forest	11,378
Charnock	Humboldt-Toiyabe National Forest	5,348
Copper Mtns.	Humboldt-Toiyabe National Forest	31,945
Currant - East Slope	Humboldt-Toiyabe National Forest	10,101
Excelsior (NV)	Inyo National Forest	7,744
Excelsior Mtns.	Humboldt-Toiyabe National Forest	69,071
Georges Canyon	Humboldt-Toiyabe National Forest	108,551
Humboldt - South	Humboldt-Toiyabe National Forest	11,152
Huntoon	Humboldt-Toiyabe National Forest	36,281
Indian Creek	Humboldt-Toiyabe National Forest	9,996
Lampson	Humboldt-Toiyabe National Forest	10,730
Long Valley	Humboldt-Toiyabe National Forest	50,472
Mckinney	Humboldt-Toiyabe National Forest	5,790
North Dobbins	Humboldt-Toiyabe National Forest	10,411
North Schell	Humboldt-Toiyabe National Forest	30,773
Northumberland	Humboldt-Toiyabe National Forest	22,464
Pearl Peak	Humboldt-Toiyabe National Forest	71,405
Pine Mtn.	Humboldt-Toiyabe National Forest	12,519
Red Peak	Humboldt-Toiyabe National Forest	7,319
Rose - Verdi	Humboldt-Toiyabe National Forest	1,155
Saulsbury	Humboldt-Toiyabe National Forest	30,957
Shellback	Humboldt-Toiyabe National Forest	36,455
Snake - Chokecherry	Humboldt-Toiyabe National Forest	30,845
Stagecoach	Humboldt-Toiyabe National Forest	7,377
Stirling - Jaybird	Humboldt-Toiyabe National Forest	2,468
Stirling - West B	Humboldt-Toiyabe National Forest	88
Stirling - West D	Humboldt-Toiyabe National Forest	134
Sugarloaf	Inyo National Forest	11,534
Table Mtn. - East	Humboldt-Toiyabe National Forest	87,789
Toiyabe Range	Humboldt-Toiyabe National Forest	99,225
Warm Springs	Humboldt-Toiyabe National Forest	29,540
West Schell	Humboldt-Toiyabe National Forest	21,656
White Pine Mtn.	Humboldt-Toiyabe National Forest	25,244
White Pine South	Humboldt-Toiyabe National Forest	11,562
White Rock Mtn	Humboldt-Toiyabe National Forest	24,917
Wildcat	Humboldt-Toiyabe National Forest	28,565
Woods	Humboldt-Toiyabe National Forest	7,467

New Mexico (4)

Area	Forest	Acres
Bull Canyon	Carson National Forest	11,512
Caja	Santa Fe National Forest	5,304
Grass Mountain	Santa Fe National Forest	3,254
South Guadalupe Mountains	Lincoln National Forest	20,930

North Dakota (6)

Area	Forest	Acres
Blacktail	Dakota Prairie Grasslands	8,620
Collar / Bennett - Cottonwood	Dakota Prairie Grasslands	19,697
Dawsons Waterhole	Dakota Prairie Grasslands	6,087
Long X Divide	Dakota Prairie Grasslands	10,099
Tracy Mountain	Dakota Prairie Grasslands	9,756
Wannagan	Dakota Prairie Grasslands	6,026

Oregon (2)

Area	Forest	Acres
Lookout Mountain	Ochoco National Forest	14,115
Shaketable	Malheur National Forest	6,764

Utah (7)

Area	Forest	Acres
0401024	Ashley National Forest	12,882
0419020	Ashley National Forest	355,684
418003	Uinta National Forest	10,912
418004	Uinta National Forest	16,661
418042	Uinta National Forest	7,313
Fishhook	Dixie National Forest	12,959
Stansbury Mountains	Wasatch-Cache National Forest	39,696

Virginia (5)

Area	Forest	Acres
Lewis Fork Addition	Jefferson National Forest	749
Little Wilson Creek Addition A	Jefferson National Forest	78
Little Wilson Creek Addition B	Jefferson National Forest	1,725
Raccoon Branch	Jefferson National Forest	4,388
Seng Mountain	Jefferson National Forest	6,428

Wyoming (7)

Area	Forest	Acres
Cloud Peak Contiguous	Bighorn National Forest	113,757
Devils Canyon	Bighorn National Forest	37,416
Horse Creek Mesa	Bighorn National Forest	77,808
Little Bighorn	Bighorn National Forest	133,949
Wapiti Valley North	Shoshone National Forest	18,345
Wapiti Valley South	Shoshone National Forest	43,517
West Slope Winds	Bridger-Teton National Forest	143,252

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