Mammal Species of the World
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Lepus californicus is found throughout the southwestern United States into Mexico, as far east as Missouri, north into Washington, Idaho, Colorado and Nebraska, and west to California and Baja California.
Biogeographic Regions: nearctic (Native )
occurs (regularly, as a native taxon) in multiple nations
Regularity: Regularly occurring
Type of Residency: Year-round
Global Range: Western North America, from the Pacific Coast east to Missouri and Arkansas, and from Washington, Idaho, southwestern Montana, eastern Wymong, and South Dakota south to Baja California, northern Sonora, southern Queretaro, and Hidalgo, central Mexico (Jones et al. 1983; Hoffmann, in Wilson and Reeder 1993; Best 1996). Releases have been made in Florida, New Jersey, Maryland, Massachusetts, and Virginia (see Best 1996).
spp.) in North America . Native black-tailed jackrabbit populations
occur from central Washington east to Missouri and south to Baja
California Sur and Zacatecas . Black-tailed jackrabbit distribution
is currently expanding eastward in the Great Plains at the expense of
white-tailed jackrabbit . Black-tailed jackrabbit has been
successfully introduced in southern Florida and along the coastline in
Maryland, New Jersey, and Virginia [13,24].
Distribution of subspecies occurring entirely or partially in the United
States is as follows :
L. c. bennettii - coastal southern California to Baja California Norte
L. c. californicus - coastal Oregon to coastal and Central Valley California
L. c. deserticola - southern Idaho to Sonora
L. c. eremicus - central Arizona to Sonora
L. c. melanotis - South Dakota to Iowa, Missouri, and central Texas
L. c. merriami - south-central and southeastern Texas to Tamaulipas
L. c. richardsonii - central California
L. c. texianus - southeastern Utah and southwestern Colorado to Zacatecas
L. c. wallawalla - eastern Washington to northeastern California and
Regional Distribution in the Western United States
This species can be found in the following regions of the western United States (according to the Bureau of Land Management classification of Physiographic Regions of the western United States):
1 Northern Pacific Border
2 Cascade Mountains
3 Southern Pacific Border
4 Sierra Mountains
5 Columbia Plateau
6 Upper Basin and Range
7 Lower Basin and Range
8 Northern Rocky Mountains
9 Middle Rocky Mountains
10 Wyoming Basin
11 Southern Rocky Mountains
12 Colorado Plateau
13 Rocky Mountain Piedmont
14 Great Plains
Occurrence in North America
Black-tailed jackrabbits measure 47-63 cm from nose to rump, the tail is between 50-112 mm and the ears are 10-13 cm long. As they are true hares, black-tailed jackrabbits are lankier and leaner than rabbits, have longer ears and legs, and the leverets are born fully-furred and open-eyed. Black-tailed jackrabbits possess a characteristic black stripe down the center of the back, a black rump patch, and the tail is black dorsally. Both sexes look alike, but the female is the larger of the two sexes.
Range mass: 1.3 to 3.1 kg.
Range length: 47 to 63 cm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: female larger
Average basal metabolic rate: 7.314 W.
Length: 63 cm
Weight: 3600 grams
Size in North America
Range: 465-630 mm
Range: 1,300-3,300 g
Chihuahuan Desert Habitat
This taxon is found in the Chihuahuan Desert, which is one of the most biologically diverse arid regions on Earth. This ecoregion extends from within the United States south into Mexico. This desert is sheltered from the influence of other arid regions such as the Sonoran Desert by the large mountain ranges of the Sierra Madres. This isolation has allowed the evolution of many endemic species; most notable is the high number of endemic plants; in fact, there are a total of 653 vertebrate taxa recorded in the Chihuahuan Desert. Moreover, this ecoregion also sustains some of the last extant populations of Mexican Prairie Dog, wild American Bison and Pronghorn Antelope.
The dominant plant species throughout the Chihuahuan Desert is Creosote Bush (Larrea tridentata). Depending on diverse factors such as type of soil, altitude, and degree of slope, L. tridentata can occur in association with other species. More generally, an association between L. tridentata, American Tarbush (Flourensia cernua) and Viscid Acacia (Acacia neovernicosa) dominates the northernmost portion of the Chihuahuan Desert. The meridional portion is abundant in Yucca and Opuntia, and the southernmost portion is inhabited by Mexican Fire-barrel Cactus (Ferocactus pilosus) and Mojave Mound Cactus (Echinocereus polyacanthus). Herbaceous elements such as Gypsum Grama (Chondrosum ramosa), Blue Grama (Bouteloua gracilis) and Hairy Grama (Chondrosum hirsuta), among others, become dominant near the Sierra Madre Occidental. In western Coahuila State, Lecheguilla Agave (Agave lechuguilla), Honey Mesquite (Prosopis glandulosa), Purple Prickly-pear (Opuntia macrocentra) and Rainbow Cactus (Echinocereus pectinatus) are the dominant vascular plants.
Because of its recent origin, few warm-blooded vertebrates are restricted to the Chihuahuan Desert scrub. However, the Chihuahuan Desert supports a large number of wide-ranging mammals, such as the Pronghorn Antelope (Antilocapra americana), Robust Cottontail (Sylvilagus robustus EN); Mule Deer (Odocoileus hemionus), Grey Fox (Unocyon cineroargentinus), Jaguar (Panthera onca), Collared Peccary or Javelina (Pecari tajacu), Desert Cottontail (Sylvilagus auduboni), Black-tailed Jackrabbit (Lepus californicus), Kangaroo Rats (Dipodomys sp.), pocket mice (Perognathus spp.), Woodrats (Neotoma spp.) and Deer Mice (Peromyscus spp). With only 24 individuals recorded in the state of Chihuahua Antilocapra americana is one of the most highly endangered taxa that inhabits this desert. The ecoregion also contains a small wild population of the highly endangered American Bison (Bison bison) and scattered populations of the highly endangered Mexican Prairie Dog (Cynomys mexicanus), as well as the Black-tailed Prairie Dog (Cynomys ludovicianus).
The Chihuahuan Desert herpetofauna typifies this ecoregion.Several lizard species are centered in the Chihuahuan Desert, and include the Texas Horned Lizard (Phrynosoma cornutum); Texas Banded Gecko (Coleonyx brevis), often found under rocks in limestone foothills; Reticulate Gecko (C. reticulatus); Greater Earless Lizard (Cophosaurus texanus); several species of spiny lizards (Scelopoprus spp.); and the Western Marbled Whiptail (Cnemidophorus tigris marmoratus). Two other whiptails, the New Mexico Whiptail (C. neomexicanus) and the Common Checkered Whiptail (C. tesselatus) occur as all-female parthenogenic clone populations in select disturbed habitats.
Representative snakes include the Trans-Pecos Rat Snake (Bogertophis subocularis), Texas Blackhead Snake (Tantilla atriceps), and Sr (Masticophis taeniatus) and Neotropical Whipsnake (M. flagellum lineatus). Endemic turtles include the Bolsón Tortoise (Gopherus flavomarginatus), Coahuilan Box Turtle (Terrapene coahuila) and several species of softshell turtles. Some reptiles and amphibians restricted to the Madrean sky island habitats include the Ridgenose Rattlesnake (Crotalus willardi), Twin-spotted Rattlesnake (C. pricei), Northern Cat-eyed Snake (Leptodeira septentrionalis), Yarrow’s Spiny Lizard (Sceloporus jarrovii), and Canyon Spotted Whiptail (Cnemidophorus burti).
There are thirty anuran species occurring in the Chihuahuan Desert: Chiricahua Leopard Frog (Rana chircahuaensis); Red Spotted Toad (Anaxyrus punctatus); American Bullfrog (Lithobates catesbeianus); Canyon Treefrog (Hyla arenicolor); Northern Cricket Frog (Acris crepitans); Rio Grande Chirping Frog (Eleutherodactylus cystignathoides); Cliff Chirping Frog (Eleutherodactylus marnockii); Spotted Chirping Frog (Eleutherodactylus guttilatus); Tarahumara Barking Frog (Craugastor tarahumaraensis); Mexican Treefrog (Smilisca baudinii); Madrean Treefrog (Hyla eximia); Montezuma Leopard Frog (Lithobates montezumae); Brown's Leopard Frog (Lithobates brownorum); Yavapai Leopard Frog (Lithobates yavapaiensis); Western Barking Frog (Craugastor augusti); Mexican Cascade Frog (Lithobates pustulosus); Lowland Burrowing Frog (Smilisca fodiens); New Mexico Spadefoot (Spea multiplicata); Plains Spadefoot (Spea bombifrons); Pine Toad (Incilius occidentalis); Woodhouse's Toad (Anaxyrus woodhousii); Couch's Spadefoot Toad (Scaphiopus couchii); Plateau Toad (Anaxyrus compactilis); Texas Toad (Anaxyrus speciosus); Dwarf Toad (Incilius canaliferus); Great Plains Narrowmouth Toad (Gastrophryne olivacea); Great Plains Toad (Anaxyrus cognatus); Eastern Green Toad (Anaxyrus debilis); Gulf Coast Toad (Incilius valliceps); and Longfoot Chirping Toad (Eleutherodactylus longipes VU). The sole salamander occurring in the Chihuahuan Desert is the Tiger Salamander (Ambystoma tigrinum).
Common bird species include the Greater Roadrunner (Geococcyx californianus), Burrowing Owl (Athene cunicularia), Merlin (Falco columbarius), Red-tailed Hawk (Buteo jamaicensis), and the rare Zone-tailed Hawk (Buteo albonotatus). Geococcyx californianus), Curve-billed Thrasher (Toxostoma curvirostra), Scaled Quail (Callipepla squamata), Scott’s Oriole (Icterus parisorum), Black-throated Sparrow (Amphispiza bilineata), Phainopepla (Phainopepla nitens), Worthen’s Sparrow (Spizella wortheni), and Cactus Wren (Campylorhynchus brunneicapillus). In addition, numerous raptors inhabit the Chihuahuan Desert and include the Great Horned Owl (Bubo virginianus) and the Elf Owl (Micrathene whitneyi).
Black-tailed jackrabbits inhabit desert scrubland, prairies, farmlands, and dunes. They favor arid regions and areas of short grass rangeland from sea level to about 3,800 m. Many different vegetation types are used, including sagebrush-creosote bush, mesquite-snakeweed and juniper-big sagebrush. They also frequent agricultural areas where they can impact fruit and grain crops.
Range elevation: 3800 (high) m.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: desert or dune ; savanna or grassland ; chaparral
Other Habitat Features: suburban ; agricultural
Habitat and Ecology
The total length of L. californicus is 46.5-63.0 cm (Hall and Kelson 1959). The breeding season is variable, contingent on latitude and environmental factors (Flinders and Chapman 2003). In Idaho the season is restricted to February to May (French et al. 1965). Where distribution occurs at lower latitudes the breeding season extends; in the southwestern USA it may last from early January to September (Griffing and Davis 1976). Gestation is variable but ranges from 40-47 days (Flinders and Chapman 2003). The litter size varies from 3.8-4.4 in the north to three to six in the south, giving a total output per female per year of about 10-14 (Best 1996). Total length at birth is variable dependent upon litter size, but a measurement in Arizona gave a length of 14.0 cm (Vorhies and Taylor 1933). Adult mortality is approximately 57%, while juvenile mean mortality ranges from 59-63% (Flinders and Chapman 2003).
Comments: Inhabits open plains, fields and deserts; open country with scattered thickets or patches of shrubs (Caire et al. 1989). Rests by day in shallow depression (form).
Black-tailed jackrabbit require shrubs or small conifers for hiding,
nesting, and thermal cover, and grassy areas for night feeding [24,48].
A shrub-grassland mosaic or widely spaced shrubs interspersed with herbs
provides hiding cover while providing feeding opportunities. Small
shrubs do not provide adequate cover [18,19,48]. On the Snake River
Birds of Prey Study Area of southwestern Idaho, black-tailed jackrabbit
was more frequent on sites dominated by big sagebrush or black
greasewood than on sites dominated by the smaller shrubs winterfat
(Krascheninnikovia lanata) or shadscale (Atriplex confertifolia).
Black-tailed jackrabbit does not habitually use a burrow , although
it has occassionally been observed using abandoned burrows for escape
 and thermal [24,65] cover.
The black-tailed jackrabbit is a habitat generalist. It can occupy a
wide range of habitats as long as there is diversity in plant species
and structure. It requires mixed grasses, forbs, and shrubs for food,
and shrubs or small trees for cover [48,55,60,36]. It prefers
moderately open areas without dense understory growth and is seldom
found in closed-canopy habitats. For example, Bell and Stadinski 
reported that in California, black-tailed jackrabbit was plentiful in
open chamise (Ademostoma fasciculatum)-Ceanothus spp. chaparral
interspersed with grasses, but did not occupy closed-canopy chaparral.
Similarly, black-tailed jackrabbit occupies clearcuts and early seral
coniferous forest, but not closed-canopy coniferous forest [8,39,80].
Black-tailed jackrabbit does not migrate or hibernate during winter
[24,39]; therefore, the same habitat is used year-round. There is
diurnal movement of 2 to 10 miles (3-16 km) from shrub cover in day to
open foraging areas at night . Home range area varies with habitat
and habitat quality . Home ranges of 0.4 to 1.2 square miles (1-3
sq km) have been reported in big sagebrush (Artemisia tridentata) and
black greasewood (Sarcobatus vermiculatus) communities of northern Utah
Associated Plant Communities
The black-tailed jackrabbit occupies plant communities with a mixture of
shrubs, grasses, and forbs. Shrubland-herb mosaics are preferred over
pure stands of shrubs or herbs . Black-tailed jackrabbit is common
in sagebrush (Artemisia spp.) [55,60], creosotebush (Larrea tridentata)
[21,57], and other desert shrublands [22,29,37]; palouse, shortgrass,
and mixed-grass prairies; desert grassland [9,29,62]; open-canopy
chaparral [1,4,80]; oak (Quercus spp.) [3,43] and pinyon-juniper
(Pinus-Juniperus spp.) [16,24] woodlands; and early seral, low- to
mid-elevation coniferous forests [39,80]. It is also common in and near
croplands, especially alfalfa (Medicago sativa) fields .
Habitat: Rangeland Cover Types
This species is known to occur in association with the following Rangeland Cover Types (as classified by the Society for Range Management, SRM):
More info for the terms: association, forb, shrub, vine
101 Bluebunch wheatgrass
102 Idaho fescue
103 Green fescue
104 Antelope bitterbrush-bluebunch wheatgrass
105 Antelope bitterbrush-Idaho fescue
106 Bluegrass scabland
107 Western juniper/big sagebrush/bluebunch wheatgrass
109 Ponderosa pine shrubland
110 Ponderosa pine-grassland
201 Blue oak woodland
202 Coast live oak woodland
203 Riparian woodland
204 North coastal shrub
205 Coastal sage shrub
206 Chamise chaparral
207 Scrub oak mixed chaparral
208 Ceanothus mixed chaparral
209 Montane shrubland
211 Creosotebush scrub
214 Coastal prairie
215 Valley grassland
301 Bluebunch wheatgrass-blue grama
303 Bluebunch wheatgrass-western wheatgrass
304 Idaho fescue-bluebunch wheatgrass
305 Idaho fescue-Richardson needlegrass
306 Idaho fescue-slender wheatgrass
307 Idaho fescue-threadleaf sedge
309 Idaho fescue-western wheatgrass
310 Needle-and-thread-blue grama
312 Rough fescue-Idaho fescue
314 Big sagebrush-bluebunch wheatgrass
315 Big sagebrush-Idaho fescue
316 Big sagebrush-rough fescue
317 Bitterbrush-bluebunch wheatgrass
318 Bitterbrush-Idaho fescue
319 Bitterbrush-rough fescue
320 Black sagebrush-bluebunch wheatgrass
321 Black sagebrush-Idaho fescue
322 Curlleaf mountain-mahogany-bluebunch wheatgrass
323 Shrubby cinquefoil-rough fescue
324 Threetip sagebrush-Idaho fescue
401 Basin big sagebrush
402 Mountain big sagebrush
403 Wyoming big sagebrush
404 Threetip sagebrush
405 Black sagebrush
406 Low sagebrush
407 Stiff sagebrush
408 Other sagebrush types
409 Tall forb
411 Aspen woodland
412 Juniper-pinyon woodland
413 Gambel oak
414 Salt desert shrub
415 Curlleaf mountain-mahogany
416 True mountain-mahogany
417 Littleleaf mountain-mahogany
503 Arizona chaparral
504 Juniper-pinyon pine woodland
505 Grama-tobosa shrub
507 Palo verde-cactus
509 Transition between oak-juniper woodland and mahogany-oak association
601 Bluestem prairie
602 Bluestem-prairie sandreed
603 Prairie sandreed-needlegrass
604 Bluestem-grama prairie
605 Sandsage prairie
611 Blue grama-buffalograss
613 Fescue grassland
614 Crested wheatgrass
701 Alkali sacaton-tobosagrass
702 Black grama-alkali sacaton
703 Black grama-sideoats grama
704 Blue grama-western wheatgrass
705 Blue grama-galleta
706 Blue grama-sideoats grama
707 Blue grama-sideoats grama-black grama
710 Bluestem prairie
711 Bluestem-sacahuista prairie
712 Galleta-alkali sacaton
717 Little bluestem-Indiangrass-Texas wintergrass
719 Mesquite-liveoak-seacoast bluestem
720 Sand bluestem-little bluestem (dunes)
721 Sand bluestem-little bluestem (plains)
722 Sand sagebrush-mixed prairie
724 Sideoats grama-New Mexico feathergrass-winterfat
725 Vine mesquite-alkali sacaton
730 Sand shinnery oak
735 Sideoats grama-sumac-juniper
802 Missouri prairie
803 Missouri glades
Habitat: Plant Associations
This species is known to occur in association with the following plant community types (as classified by Küchler 1964):
More info for the term: shrub
K001 Spruce-cedar-hemlock forest
K002 Cedar-hemlock-Douglas-fir forest
K003 Silver fir-Douglas-fir forest
K004 Fir-hemlock forest
K005 Mixed conifer forest
K006 Redwood forest
K007 Red fir forest
K008 Lodgepole pine-subalpine forest
K009 Pine-cypress forest
K010 Ponderosa shrub forest
K011 Western ponderosa forest
K012 Douglas-fir forest
K018 Pine-Douglas-fir forest
K019 Arizona pine forest
K022 Great Basin pine forest
K023 Juniper-pinyon woodland
K024 Juniper steppe woodland
K025 Alder-ash forest
K026 Oregon oakwoods
K027 Mesquite bosque
K028 Mosaic of K002 and K026
K029 California mixed evergreen forest
K030 California oakwoods
K031 Oak-juniper woodlands
K032 Transition between K031 and K037
K034 Montane chaparral
K035 Coastal sagebrush
K037 Mountain-mahogany-oak scrub
K038 Great Basin sagebrush
K043 Paloverde-cactus shrub
K045 Ceniza shrub
K048 California steppe
K053 Grama-galleta steppe
K054 Grama-tobosa prairie
K056 Wheatgrass-needlegrass shrubsteppe
K057 Galleta-three-awn shrubsteppe
K058 Grama-tobosa shrubsteppe
K059 Trans-Pecos shrub savanna
K060 Mesquite savanna
K061 Mesquite-acacia savanna
K062 Mesquite-live oak savanna
K063 Foothills prairie
K069 Bluestem-grama prairie
K070 Sandsage-bluestem prairie
K074 Bluestem prairie
K075 Nebraska Sandhills prairie
K076 Blackland prairie
K077 Bluestem-sacahuista prairie
K081 Oak savanna
K083 Cedar glades
K086 Juniper-oak savanna
K087 Mesquite-oak savanna
K088 Fayette prairie
This species is known to occur in the following ecosystem types (as named by the U.S. Forest Service in their Forest and Range Ecosystem [FRES] Type classification):
FRES13 Loblolly-shortleaf pine
FRES21 Ponderosa pine
FRES22 Western white pine
FRES24 Hemlock-Sitka spruce
FRES26 Lodgepole pine
FRES28 Western hardwoods
FRES30 Desert shrub
FRES32 Texas savanna
FRES33 Southwestern shrubsteppe
FRES34 Chaparral-mountain shrub
FRES36 Mountain grasslands
FRES38 Plains grasslands
FRES40 Desert grasslands
FRES41 Wet grasslands
FRES42 Annual grasslands
Habitat: Cover Types
This species is known to occur in association with the following cover types (as classified by the Society of American Foresters):
66 Ashe juniper-redberry (Pinchot) juniper
67 Mohrs (shin) oak
205 Mountain hemlock
207 Red fir
209 Bristlecone pine
210 Interior Douglas-fir
211 White fir
218 Lodgepole pine
219 Limber pine
220 Rocky Mountain juniper
221 Red alder
222 Black cottonwood-willow
223 Sitka spruce
224 Western hemlock
225 Western hemlock-Sitka spruce
226 Coastal true fir-hemlock
229 Pacific Douglas-fir
230 Douglas-fir-western hemlock
233 Oregon white oak
234 Douglas-fir-tanoak-Pacific madrone
237 Interior ponderosa pine
238 Western juniper
240 Arizona cypress
241 Western live oak
243 Sierra Nevada mixed conifer
244 Pacific ponderosa pine-Douglas-fir
245 Pacific ponderosa pine
246 California black oak
247 Jeffrey pine
248 Knobcone pine
249 Canyon live oak
250 Blue oak-foothills pine
255 California coast live oak
256 California mixed subalpine
Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
Grasses and herbaceous matter are the preferred foods of Lepus californicus, but twigs and young bark of woody plants are the staple food when other plants are not available. Sagebrush and cacti are also taken. Jackrabbits eat almost constantly and consume large quantities relative to their size; 15 jackrabbits eat as much as a large grazing cattle in one day. Black-tailed jackrabbits do not require much water and obtain nearly all the water they need from the plant material they consume.
Plant Foods: leaves; roots and tubers; wood, bark, or stems; fruit
Primary Diet: herbivore (Folivore )
Comments: Forages on grasses, forbs, crops and hay in summer; buds, bark, leaves of woody plants in winter. Obtains water from vegetation. Reingests soft fecal pellets produced while resting.
The black-tailed jackrabbit diet is composed of shrubs, small trees,
grasses, and forbs. Throughout the course of a year, black-tailed
jackrabbit feed on most if not all of the important plant species in a
community . Growth stage and moisture content of plants may
influence selection more than species . Shrubs generally comprise
the bulk of fall and winter diets, while grasses and forbs are used in
spring and early summer. This pattern varies with climate: Herbaceous
plants are grazed during greenup periods while the plants are in
prereproductive to early reproductive stages, and shrubs are utilized
more in dry seasons [2,29,59,82]. Shrubs are browsed throughout the
year, however. Most of a jackrabbit's (Lepus spp.) body water is
replaced by foraging water-rich vegetation [81,85]. Jackrabbit require
a plant's water weight to be at least five times its dry weight in
order to meet daily water intake requirements. Therefore, black-tailed
jackrabbit switch to phreatophyte shrubs when herbaceous vegetation
Plant species used by black-tailed jackrabbit are well documented for
desert regions. Forage use in other regions is less well known;
however, it is well established that black-tailed jackrabbit browse
Douglas-fir (Psedotsuga menzeisii), ponderosa pine (Pinus ponderosa),
lodgepole pine (P. contorta), and western hemlock (Tsuga heterophylla)
seedlings, and oak (Quercus spp.) seedlings and sprouts [22,39,43].
Great Basin: Big sagebrush is a primary forage species and is used
throughout the year; in southern Idaho it formed 16 to 21 percent of the
black-tailed jackrabbit summer diet. Rabbitbrush (Chrysothamnus spp.),
spiny hopsage (Gray spinosa), and black greasewood are also browsed
[2,28]. Four-wing saltbush (Atriplex canescens) is heavily used in
western Nevada . In Butte County, Idaho, winterfat comprised 41
percent of black-tailed jackrabbits' annual diet. Fourteen percent was
composed of grasses, with most grass consumption in March and April
. Russian-thistle (Salsola kali) is an important forb diet item.
Needle-and-thread grass (Stipa comata) and Indian ricegrass (Oryzopsis
hymenoides) are preferred grasses . Other preferred native grasses
include Sandberg bluegrass (Poa secunda) and bluebunch wheatgrass
(Pseudoroegneria spicata) . Where available, crested wheatgrass
(Agropyron desertorum and A. cristatum) and barley (Horeum vulgare) are
highly preferred. Cheatgrass (Bromus tectorum) use is variable: It
comprised 45 percent of the April diet on two southern Idaho sites ,
but black-tailed jackrabbit on an eastern Washington site did not use it
Warm Desert: Mesquite (Prosopis spp.)  and creosotebush (Larrea
tridentata) [57,81] are principle browse species. Broom snakeweed
(Gutierrezia sarothrae) and Yucca spp.  are also used. In honey
mesquite (P. glandulosa var. glandulosa) communities in New Mexico,
overall black-tailed jackrabbit diet was 47 percent shrubs, 22 percent
grasses, and 31 percent forbs . Black grama, dropseed (Sporobolus
spp), fluffgrass (Erioneuron pulchellum), and threeawns (Aristida spp.)
are the most commonly grazed grasses [18,29,82]. Leather croton (Croton
pottsii), silverleaf nightshade (Solanum alaeagnifolium), desert
marigold (Baileya multiradiata), wooly paperflower (Psilostrophe
tagetina), and globemallow (Sphaeralcea spp.) are important forbs,
although many forb species are grazed . Opuntia spp., saguaro
(Carnegiea gigantea), and other cacti are used throughout the year but
are especially important in dry seasons as a source of moisture .
and carnivorous mammals. Nydegger and Smith  rated black-tailed
jackrabbit and Townsend's ground squirrel (Spermophilus townsendii) as
the two most important prey species on the Snake River Birds of Prey
Study Area. Hawks preying on black-tailed jackrabbit include the
ferruginous hawk (Buteo regalis) [5,45,47,85], white-tailed hawk (B.
albicaudatus) , Swainson's hawk (B. swainsoni), and red-tailed hawk
(B. jamaicensis) . Janes  reported black-tailed jackrabbit as
the primary prey of Swainson's, red-tailed, and ferruginous hawks on
Idaho and Utah sites. Other raptors consuming black-tailed jackrabbit
include the great horned owl (Bubo virginianus), burrowing owl (Athene
cunicularia), golden eagle (Aquila chrysaetos), and bald eagle
(Haliaeetus leucocephalus) [37,90]. Nydegger and Smith  reported a
significant correlation between golden eagle production and black-tailed
jackrabbit productivity on the Snake River Birds of Prey Study Area. In
Colorado and southeastern Wyoming, black-tailed jackrabbit constituted 9
percent of nesting bald eagle's diet . Jackrabbits (Lepus spp.) and
cottontails (Sylvilagus spp.) combined formed 9 percent of the diet of
bald eagles wintering on National Forests in Arizona and New Mexico
Mammalian predators include coyote (Canis latrans), domestic dog (C.
familiaris), red fox (Vulpes vulpes), common gray fox (Urocyon
cinereoargenteus), American badger (Taxidea taxus), mountain lion (Felis
concolor), housecat (F. catus), and bobcat (Lynx rufus) [24,39,68]. In
many areas, black-tailed jackrabbit is the primary item in coyote diets
[1,325,45]. It is locally and regionally important to other mammalian
predators. One study  found that jackrabbits (Lepus spp.) made up
45 percent of the bobcat diet in Utah and Nevada. Another Utah-Nevada
study  found that jackrabbits were the fourth most commonly consumed
prey of mountain lion.
Rattlesnakes (Crotalus spp.) and garter snake (Thamnophis sirtalis) prey
on black-tailed jackrabbit young [54,81]. Raccoon (Procyon lotor) and
striped skunk (Mephitis mephitis) may also capture young .
Humans hunt black-tailed jackrabbit for food and hunt, trap, or poison
it as a pest species .
Based on studies in:
USA: California, Cabrillo Point (Grassland)
USA: Texas, Franklin Mtns (Carrion substrate)
This list may not be complete but is based on published studies.
Known prey organisms
Based on studies in:
USA: California, Cabrillo Point (Grassland)
This list may not be complete but is based on published studies.
Populations are known to fluctuate markedly, slowly reaching peak over several years, falling off rapidly in several weeks or months (Larrison and Johnson 1981). Populations increase with overgrazing. Commonly carries tularemia. May travel up to a mile from daytime retreat to night feeding area. May gather in large group to feed. Home range varies from less than 1 sq km to 3 sq km in northern Utah (Smith 1990).
Habitat-related Fire Effects
Patchy fire in big sagebrush and other shrub types can benefit
black-tailed jackrabbit by increasing grass and forb production adjacent
to shrub cover. In Idaho black-tailed jackrabbit density was
significantly (p less than 0.01) higher in big sagebrush plots prescribed burned
than on unburned plots in two of four counts. Density was similar on
burned and control plots on the other two counts. Reducing shrub cover
over large areas, however, can increase mortality from predation due to
cover removal . Patchy fire in coniferous forest types probably
also benefits black-tailed jackrabbit by reducing the overstory and
encouraging growth of herbs, shrubs, and small conifers.
Great Basin: Fire frequencies on some big sagebrush habitats of the
Great Basin have increased from historical ranges of 30 to 70 years to
an average of 5.5 years [10,86,87]. Cheatgrass, an exotic that forms
dense stands and dries out earlier than native grasses, has been
implicated in changing the fire regime. Big sagebrush has declined with
frequent fire . Loss of big sagebrush forage and cover has caused a
steady decline in black-tailed jackrabbit populations in affected areas
[60,84,85]. Some raptor populations are declining as well [60,85].
Wicklow-Howard  recommended revegetating these areas with big
sagebrush after fire to increase black-tailed jackrabbit and raptor
Timing of Major Life History Events
Breeding: Male black-tailed jackrabbit reach sexual maturity at about 7
months of age . Females usually breed in the spring of their second
year, although females born in spring or early summer may breed in their
first year. Ovulation is induced by copulation . The breeding
season is variable depending upon latitude and environmental factors.
In the northern part of its range in Idaho, black-tailed jackrabbit
breeds from February through May . In Utah, Gross and others 
reported breeding from January through July, with over 75 percent of
females pregnant by April. The Kansas breeding season extends from
January to August . Breeding in warm climates continues nearly
year-round. Two peak breeding seasons corresponding to rainfall
patterns and vegetation greenup occur in California , Arizona ,
and New Mexico . In Arizona, for example, breeding peaks during
winter (January-March) rains and again during June monsoons .
Gestation and Nesting: The gestation period ranges from 41 to 47 days
[40,44]. More litters are born in warm climates: Number of litters
born each year ranged from two per year in Idaho  to seven in
Arizona . Litter sizes are largest in the northern portions of
black-tailed jabbit's range, however, and decrease with latitude.
Average litter size has been reported at 4.9 in Idaho , 3.8 in Utah
, and 2.2 in Arizona .
Female black-tailed jackrabbit do not prepare an elaborate nest. They
give birth in shallow excavations called forms that are no more than a
few centimeters deep. Females may line forms with hair prior to
parturition, but some drop litters in existing depressions on the ground
with no further preparation [67,68]. Young are borne fully furred with
eyes open, and are mobile within minutes of birth [24,90]. Females do
not protect or even stay with the young except during nursing .
Ages of weaning and dispersal are unclear since the young are well
camouflaged and rarely observed in the field. Captive black-tailed
jackrabbit are fully weaned by 8 weeks . The young apparently stay
together for at least a week after leaving the form [24,65].
Life History and Behavior
Perception Channels: tactile ; chemical
Comments: Active throughout the year. Primarily crepuscular and nocturnal.
Status: captivity: 6.8 years.
Lifespan, longevity, and ageing
Black-tailed jackrabbit males and females leap after, chase, and behave aggressively towards each other during a brief courtship phase before mating.
Mating System: polygynandrous (promiscuous)
Breeding season for Lepus californicus extends from December through September in Arizona and from late January to August in California and Kansas. Females produce 3 or 4 litters annually with 1-6 leverets (generally 3 or 4) after a 41-47 day gestation period. The young are precocial; females only nurse their offspring for 2-3 days and are not seen with their young after that time. Lifespan in captivity is 5-6 years, but rabbits in the wild often die much sooner due to predation, disease or problems associated with overpopulation.
Range number of offspring: 1 to 8.
Average number of offspring: 2.26.
Range gestation period: 41 to 47 days.
Average gestation period: 43 days.
Range weaning age: 14 to 21 days.
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
Average birth mass: 84.34 g.
Average number of offspring: 1.
Average age at sexual or reproductive maturity (female)
Sex: female: 243 days.
Parental Investment: precocial
Breeding period may extend from late winter to late summer. Gestation lasts 41-47 days. Females produce 1-4 litters of 1-8 (usually 2-4) precocial young each year (Jones et al. 1983).
Evolution and Systematics
The large ears of the jack rabbit are used in cooling, radiating heat via an extensive network of blood vessels.
"Many desert animals have large ears, and the jack rabbit is no exception. It has been suggested that large ears, with their network of blood vessels, may serve to radiate heat to the sky while the animal is resting in the shade, so helping to lower its body temperature." (Foy and Oxford Scientific Films 1982:165)
"Blood flow to the ear pinnae is curtailed at ambient temperatures of between 1.4° and 24.0° C, which minimizes heat loss across the pinnae and allows the surfaces of erect pinnae to approach ambient temperature. The pinnae are warmed by steady or pulsatile vasodilation in some animals when the ambient temperature is between 1° and 9° C below body temperature, a response favoring heat loss. When ambient temperature exceeds body temperature by 4° to 5° C, the pinnae are circulated with blood cooler than ambient temperature; this response favors heat influx." (Hill and Vegth 1976:436)
Learn more about this functional adaptation.
- Foy, Sally; Oxford Scientific Films. 1982. The Grand Design: Form and Colour in Animals. Lingfield, Surrey, U.K.: BLA Publishing Limited for J.M.Dent & Sons Ltd, Aldine House, London. 238 p.
- Hill RW; Vegthe JH. 1976. Jackrabbit ears: surface temperatures and vascular responses. Science. 194(4263):
- Mohler FS; Heath JE. 1988. Comparison of IR thermography and thermocouple measurement of heat loss from rabbit pinna. American Journal of Physiology - Regulatory Integrative and Comparative Physiology. 254(2): 389-395.
- Wathen P; Mitchell JW; Porter WP. 1971. Theoretical and experimental studies of energy exchange from jackrabbit ears and cylindrically shaped appendages. Biophysical Journal. 11(12): 1030-1047.
Molecular Biology and Genetics
Statistics of barcoding coverage: Lepus californicus
Public Records: 0
Specimens with Barcodes: 137
Species With Barcodes: 1
Population numbers of black-tailed jackrabbits are sometimes quite high despite attempts at culling their populations by ranchers and farmers. Population densities often reach 470 animals per square km, with densities as high as 1500 animals per square km being recorded. Large herding attempts have netted as much as 6,000 hares at a time. As with many hares, Lepus californicus populations undergo drastic fluctuations, with population numbers peaking every 6 to 10 years. In some years more then 90 per cent of western populations die from tularemia, which may or may not be related to the population cycling phenomenon. Because of their incredible fecundity, black-tailed jackrabbit numbers quickly recover from these kinds of die-offs.
Black-tailed jackrabbit populations are not threatened in general, though extensive habitat destruction may reduce suitable habitat.
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
- Wilson, D., S. Ruff. 1999. The Smithsonian Book of North American Mammals. Washington: Smithsonian Institution Press.
IUCN Red List Assessment
Red List Category
Red List Criteria
National NatureServe Conservation Status
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
United States and Canada is available at NatureServe, although recent changes
in status may not be included.
14-37 individuals/km² shrublands
12-44 individuals/km² grassland.
Use of Fire in Population Management
Jackrabbits (Lepus spp.) moved onto a burn in Arizona desert shrubsteppe
immediately after a November precribed fire. Jackrabbits foraged in the
burn through winter and into spring .
California chaparral: Closed-canopy chamise chaparral in Lake County
was prescribed burned in May to enhance wildlife habitat. Treatment was
creating small (5-10 acre [2-4 ha]) openings in the dense shrubs and
seeding the burned areas with annual and perennial herbs. Prefire
density of black-tailed jackrabbit was approximately 1 jackrabbit/sq
mile; density at postfire year 1 was approximately 5 to 10 jackrabbits/sq
mile. Burn use was heaviest in summer. Black-tailed jackrabbit grazed
the seeded-in perennials heavily. Most of the annuals were grazed only
lightly; however, cultivated rye (Secale cereale) was preferred. Soft
chess (Bromus hordeaceus) foliage was not grazed, but black-tailed
jackrabbit ate the ripe seeds .
Fifty percent removal of the canopy by prescribed fire in
chamise-ceanothus chaparral on the Cleveland National Forest attracted
black-tailed jackrabbit to the burned areas. They did not use unburned
areas with closed canopies .
Black-tailed jackrabbit populations undergo periodic peaks and lows
every 3 to 10 years [18,19,24]. Northern Utah populations, for example,
reached a peak density of 71.4 black-tailed jackrabbits/sq km in 1970,
declined to a low of 47.1 black-tailed jackrabbits/sq km in 1972
(Stoddart in ), and peaked to approximate 1970 levels in 1979 .
Large populations can overgraze ranges and depradate croplands and
conifer plantations [8,13,24,39,81]. Black-tailed jackrabbit control
methods are reviewed in several publications [26,39,50].
Range: When populations are between peaks, black-tailed jackrabbit
presence may complement livestock grazing. Daniel and others [18,19]
reported that at moderate stocking rates and average black-tailed
jackrabbit numbers, there was little competition for forage between
cattle and black-tailed jackrabbit on a Chihuahua Desert
creosotebush-honey mesquite rangeland. The black-tailed jackrabbit
browsed shrubs such as creosotebush that the cattle found unpalatable.
In addition, the black-tailed jackrabbit consumed native poisonous
plants such as locoweed (Astragulus spp.), desert marigold, and wooly
paperflower, thereby reducing poisonous plant cover. Thirty-six percent
of their total diet was composed of plants poisonous to cattle. Daniel
and others  also found that black-tailed jackrabbit densities were
significantly (p less than 0.10) higher on rangeland in fair condition than on
good condition rangelands. They suggested that maintaining rangelands
in good to excellent condition may be the best way to control
black-tailed jackrabbit populations.
Black-tailed jackrabbit populations in some areas of the Great Basin
have been declining for 20 to 25 years. There has been an attendant
population decline of some raptor species including ferruginous hawk
 and golden eagle . See HABITAT RELATED FIRE EFFECTS for
Black-tailed jackrabbit browse saltcedar (Tamarix ramosissima). It is
apparently the only vertebrate herbivore in the United States to do so
Seeds of several plant species are dispersed in black-tailed jackrabbit
feces including dropseeds (Sporobolus spp.)  and prickly pear
(Opuntia spp.) .
Timber: In coniferous forests, management practices that reduce edge
also reduce black-tailed jackrabbit populations. Roads, skid trails,
and patchy canopy cover have been found to increase populations .
Lagomorphs can reduce conifer seedling survival. Lagomorph damage to
young conifers can be confirmed by examining injured trees. Because
they clip trees at an angle with sharp incisors, lagomorphs leave
smooth, oblique cuts on branchs and twigs. Lacking sharp incisors, deer
(Odocoileus spp.) and elk (Cervus elaphus) leave jagged tears. Clean
branch cuts and fecal pellets, which jackrabbits and rabbits often drop
at feeding sites, signal lagomorph damage .
Human Health: The black-tailed jackrabbit is a reservoir for several
diseases transmittable to humans including tularemia, bubonic plague,
and Lyme disease [24,53,81].
Relevance to Humans and Ecosystems
Due to the removal of natural predators, such as coyote and kit fox, by European settlers, black-tailed jackrabbit populations have undergone incredible population explosions in which crops, orchards, and rangelands have suffered. They do considerable damange to farms, forest plantations, and young trees.
Negative Impacts: crop pest
As with many other Lepus species, L. californicus has been widely used as food for humans, especially by Native Americans. Their fur is not durable nor valuable, but it has been extensively used in the manufacture of felt and as trimming and lining for garments and gloves.
Positive Impacts: food ; body parts are source of valuable material
Comments: Sometimes regarded as a pest in certain areas; may damage rangeland, hayfields, and cultivated crops in years of abundance.
Hunted for sport and food. When very abundant, may be herded and killed; meat has been used for dog food (Caire et al. 1989).
The black-tailed jackrabbit (Lepus californicus), also known as the American desert hare, is a common hare of the western United States and Mexico, where it is found at elevations from sea level to up to 10,000 feet (3,000 m). Reaching a length of about 2 feet (61 cm), and a weight from 3 to 6 pounds (1.4 to 2.7 kg), the black-tailed jackrabbit is the third largest North American hare, after the antelope jackrabbit and the white-tailed jackrabbit. The black-tailed jackrabbits occupy mixed shrub-grassland terrains. Their breeding depends on the location; it typically peaks in spring, but may continue all year round in warm climates. Young are born fully furred with eyes open; they are well camouflaged and are mobile within minutes of birth, thus females do not protect or even stay with the young except during nursing. The average litter size is around four, but may be as low as two and as high as seven in warm regions.
The black-tailed jackrabbit does not migrate or hibernate during winter and uses the same habitat of 0.4 to 1.2 square miles (1–3 km2) year-round. Its diet is composed of various shrubs, small trees, grasses and forbs. Shrubs generally comprise the bulk of fall and winter diets, while grasses and forbs are used in spring and early summer, but the pattern and plant species vary with climate. Black-tailed jackrabbit is an important prey species for raptors and carnivorous mammals, such as eagles, hawks, owls, coyotes, foxes, and wild cats. The rabbits host many ectoparasites including fleas, ticks, lice, and mites; for this reason, hunters often avoid collecting them.
Like other jackrabbits, the blacktail has distinctive long ears, and the long, powerful rear legs characteristic of hares. Reaching a length of about 2 feet (61 cm), and a weight from 3 to 6 pounds (1.4 to 2.7 kg), the black-tailed jackrabbit is the third largest North American hare, after the antelope jackrabbit and the white-tailed jackrabbit. The black-tailed jackrabbit's dorsal fur is agouti (dark buff peppered with black), and its undersides and the insides of its legs are creamy white. The ears are black-tipped on the outer surface, and unpigmented inside. The ventral surface of the tail is grey to white, and the black dorsal surface of the tail continues up the spine for a few inches to form a short, black stripe. The females are larger than males, with no other significant differences.
Taxonomy and distribution
Although seventeen subspecies are recognized, this number may be excessive. Using cluster analysis of anatomical characters, Dixon and others found that black-tailed jackrabbit subspecies separated into two distinct groups that are geographically separated west and east of the Colorado Rocky Mountains and the Colorado River. They suggested only two infrataxa are warranted: the western subspecies L. c. californicus and the eastern subspecies L. c. texianus.
Black-tailed jackrabbit is the most widely distributed jackrabbit (Lepus spp.) in North America. Native black-tailed jackrabbit populations occur from central Washington east to Missouri and south to Baja California Sur and Zacatecas. Black-tailed jackrabbit distribution is currently expanding eastward in the Great Plains at the expense of white-tailed jackrabbit. Black-tailed jackrabbit has been successfully introduced in southern Florida and along the coastline in Maryland, New Jersey, and Virginia.
- Lepus californicus altamirae (Nelson)
- L. c. asellus (G. S. Miller)
- L. c. bennettii (Gray) – coastal southern California to Baja California Norte
- L. c. californicus (Gray) – coastal Oregon to coastal and Central Valley California
- L. c. curti (E. R. Hall)
- L. c. deserticola (Mearns) – southern Idaho to Sonora
- L. c. ememicus (J. A. Allen) – central Arizona to Sonora
- L. c. festinus (Nelson)
- L. c. magdalenae (Nelson)
- L. c. martirensis (J. M. Stowell)
- L. c. melanotis (Mearns) – South Dakota to Iowa, Missouri, and central Texas
- L. c. merriamai (Mearns) – south-central and southeastern Texas to Tamaulipas
- L. c. richardsonii (Bachman) – central California
- L. c. sheldoni (W. H. Burt)
- L. c. texianus (Waterhouse) – southeastern Utah and southwestern Colorado to Zacatecas
- L. c. wallawalla (Merriam) – eastern Washington to northeastern California and northwestern Nevada
- L. c. xanti (Thomas)
The black-tailed jackrabbit occupies plant communities with a mixture of shrubs, grasses, and forbs. Shrubland-herb mosaics are preferred over pure stands of shrubs or herbs. Black-tailed jackrabbit is common in sagebrush (Artemisia spp.), creosotebush (Larrea tridentata), and other desert shrublands; palouse, shortgrass, and mixed-grass prairies; desert grassland; open-canopy chaparral; oak (Quercus spp.) and pinyon-juniper (Pinus-Juniperus spp.) woodlands; and early seral (succeeding each other), low- to mid-elevation coniferous forests. It is also common in and near croplands, especially alfalfa (Medicago sativa) fields.
Major life events
Male black-tailed jackrabbit reach sexual maturity at about 7 months of age. Females usually breed in the spring of their second year, although females born in spring or early summer may breed in their first year. Ovulation is induced by copulation. The breeding season is variable depending upon latitude and environmental factors. In the northern part of its range in Idaho, black-tailed jackrabbit breeds from February through May. In Utah, black-tailed jackrabbit breed from January through July, with over 75% of females pregnant by April. The Kansas breeding season extends from January to August. Breeding in warm climates continues nearly year-round. Two peak breeding seasons corresponding to rainfall patterns and growth of young vegetation occur in California, Arizona, and New Mexico. In Arizona, for example, breeding peaks during winter (January–March) rains and again during June monsoons.
The gestation period ranges from 41 to 47 days. More litters are born in warm climates: the number of litters born each year ranges from two per year in Idaho to seven in Arizona. Litter sizes are largest in the northern portions of black-tailed jackrabbit's range and decrease toward the south. Average litter size has been reported at 4.9 in Idaho, 3.8 in Utah, and 2.2 in Arizona.
Female black-tailed jackrabbit do not prepare an elaborate nest. They give birth in shallow excavations called forms that are no more than a few centimeters deep. Females may line forms with hair prior to giving birth, but some drop litters in existing depressions on the ground with no further preparation. Young are borne fully furred with eyes open, and are mobile within minutes of birth. Females do not protect or even stay with the young except during nursing. Ages of weaning and dispersal are unclear since the young are well camouflaged and rarely observed in the field. Captive black-tailed jackrabbit are fully weaned by 8 weeks. The young stay together for at least a week after leaving the form.
The black-tailed jackrabbit can occupy a wide range of habitats as long as there is diversity in plant species. It requires mixed grasses, forbs, and shrubs for food, and shrubs or small trees for cover. It prefers moderately open areas without dense understory growth and is seldom found in closed-canopy habitats. For example, in California, black-tailed jackrabbit is plentiful in open chamise (Ademostoma fasciculatum Ceanothus spp.) chaparral interspersed with grasses, but does not occupy closed-canopy chaparral. Similarly, black-tailed jackrabbit occupies clearcuts and early seral coniferous forest, but not closed-canopy coniferous forest.
Black-tailed jackrabbit does not migrate or hibernate during winter; the same habitat is used year-round. There is diurnal movement of 2 to 10 miles (3–16 km) from shrub cover in day to open foraging areas at night. Home range area varies with habitat and habitat quality. Home ranges of 0.4 to 1.2 square miles (1–3 km2) have been reported in big sagebrush (Artemisia tridentata) and black greasewood (Sarcobatus vermiculatus) communities of northern Utah.
Black-tailed jackrabbit require shrubs or small conifers for hiding, nesting, and thermal cover, and grassy areas for night feeding. A shrub-grassland mosaic or widely spaced shrubs interspersed with herbs provides hiding cover while providing feeding opportunities. Small shrubs do not provide adequate cover. In the Snake River Birds of Prey Study Area in southwestern Idaho, black-tailed jackrabbit was more frequent on sites dominated by big sagebrush or black greasewood than on sites dominated by the smaller shrubs winterfat (Krascheninnikovia lanata) or shadscale (Atriplex confertifolia). Black-tailed jackrabbit does not habitually use a burrow, although it has occasionally been observed using abandoned burrows for escape and thermal cover.
The black-tailed jackrabbit diet is composed of shrubs, small trees, grasses, and forbs. Throughout the course of a year, black-tailed jackrabbit feed on most if not all of the important plant species in a community. Growth stage and moisture content of plants may influence selection more than species. Shrubs generally comprise the bulk of fall and winter diets, while grasses and forbs are used in spring and early summer. This pattern varies with climate: herbaceous plants are grazed during greenup periods while the plants are in prereproductive to early reproductive stages, and shrubs are utilized more in dry seasons. Shrubs are browsed throughout the year, however. Most of a jackrabbit's (Lepus spp.) body water is replaced by foraging water-rich vegetation. Jackrabbit require a plant's water weight to be at least five times its dry weight in order to meet daily water intake requirements. Therefore, black-tailed jackrabbits switch to phreatophyte (deep-rooted) shrubs when herbaceous vegetation is recovering from their foraging.
Plant species used by black-tailed jackrabbit are well documented for desert regions. Forage use in other regions is less well known. However, black-tailed jackrabbit browse Douglas fir (Pseudotsuga menziesii), ponderosa pine (Pinus ponderosa), lodgepole pine (P. contorta), and western hemlock (Tsuga heterophylla) seedlings, and oak (Quercus spp.) seedlings and sprouts.
In Great Basin, big sagebrush is a primary forage species and is used throughout the year; in southern Idaho it forms 16–21% of the black-tailed jackrabbit summer diet. Rabbitbrush (Chrysothamnus spp.), spiny hopsage (Gray spinosa), and black greasewood are also browsed. Four-wing saltbush (Atriplex canescens) is heavily used in western Nevada. In Butte County, Idaho, winterfat comprises 41% of black-tailed jackrabbits' annual diet. Grasses comprise 14% of the diet, with most grass consumption in March and April. Russian thistle (Salsola kali) is an important forb diet item. Needle-and-thread grass (Stipa comata) and Indian ricegrass (Oryzopsis hymenoides) are preferred grasses. Other preferred native grasses include Sandberg bluegrass (Poa secunda) and bluebunch wheatgrass (Pseudoroegneria spicata). Where available, crested wheatgrass (Agropyron desertorum and Agropyron cristatum) and barley (Hordeum vulgare) are highly preferred. Cheatgrass (Bromus tectorum) use is variable: it comprises 45% of the April diet on two southern Idaho sites, but black-tailed jackrabbit on an eastern Washington site do not use it.
In warm desert, mesquite (Prosopis spp.) and creosotebush (Larrea tridentata) are principal browse species. Broom snakeweed (Gutierrezia sarothrae) and Yucca spp. are also used. In honey mesquite (Prosopis glandulosa var. glandulosa) communities in New Mexico, overall black-tailed jackrabbit diet was 47% shrubs, 22% grasses, and 31% forbs. Black grama (Bouteloua spp.), dropseed (Sporobolus spp.), fluffgrass (Erioneuron pulchellum), and threeawns (Aristida spp.) are the most commonly grazed grasses. Leather croton (Croton pottsii), silverleaf nightshade (Solanum elaeagnifolium), desert marigold (Baileya multiradiata), wooly paperflower (Psilostrophe tagetina), and globemallow (Sphaeralcea spp.) are important forbs, although many forb species are grazed. Opuntia spp., saguaro (Carnegiea gigantea), and other cacti are used throughout the year but are especially important in dry seasons as a source of moisture.
Black-tailed jackrabbit is an important prey species for many raptors and carnivorous mammals. The black-tailed jackrabbit and Townsend's ground squirrel (Spermophilus townsendii) are the two most important prey species on the Snake River Birds of Prey Study Area. Hawks preying on black-tailed jackrabbit include the ferruginous hawk (Buteo regalis), white-tailed hawk (Buteo albicaudatus), Swainson's hawk (B. swainsoni), and red-tailed hawk (B. jamaicensis). The black-tailed jackrabbit is the primary prey of Swainson's, red-tailed, and ferruginous hawks on Idaho and Utah sites. Other raptors consuming black-tailed jackrabbit include the great horned owl (Bubo virginianus), burrowing owl (Athene cunicularia), golden eagle (Aquila chrysaetos), bald eagle (Haliaeetus leucocephalus), and Eurasian eagle-owl (Bubo bubo). There is a significant correlation between golden eagle and black-tailed jackrabbit reproduction patterns. In Colorado and southeastern Wyoming, black-tailed jackrabbit constitute 9% of nesting bald eagles' diet. Jackrabbits (Lepus spp.) and cottontails (Sylvilagus spp.) combined form 9% of the diet of bald eagles wintering on National Forests in Arizona and New Mexico.
Mammalian predators include coyote (Canis latrans), bobcat (Lynx rufus), lynx (Lynx canadensis), domestic dog (Canis lupus familiaris), domestic cat (Felis catus), red fox (Vulpes vulpes), common gray fox (Urocyon cinereoargenteus), American badger (Taxidea taxus), wolf (Canis lupus), and mountain lion (Felis concolor). In many areas, black-tailed jackrabbit is the primary item in coyote diets. It is locally and regionally important to other mammalian predators. One study found that jackrabbits (Lepus spp.) made up 45% of the bobcat diet in Utah and Nevada. Another Utah–Nevada study found that jackrabbits were the fourth most commonly consumed prey of mountain lion.
Rattlesnakes (Crotalus spp.) and garter snakes (Thamnophis sirtalis) prey on black-tailed jackrabbit young. Raccoons (Procyon lotor) and striped skunks (Mephitis mephitis) may also capture young.
Parasites and disease
The black-tailed jackrabbit plays host to many ectoparasites including fleas, ticks, lice, and mites, and many endoparasites including trematodes, cestodes, nematodes, and botfly (Cuterebra) larvae. Diseases affecting the black-tailed jackrabbit in the West are tularemia, equine encephalitis, brucellosis, Q fever, and Rocky Mountain spotted fever. Ticks are vectors for tularemia, and infected ticks have been found on jackrabbits in the West. Jackrabbits infected with tularemia die very quickly.
The high prevalence of disease and parasites in wild jackrabbits affects human predation. Many hunters will not collect the jackrabbits they shoot, and those who do are well advised to wear gloves while handling carcasses and to cook the meat thoroughly to avoid contracting tularemia. Most hunting of jackrabbits is done for pest control or sport.
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Names and Taxonomy
Lepus californicus Gray (Leporidae) [13,15,23,24,42]. Seventeen
subspecies are recognized:
L. c. altamirae Nelson [13,42]
L. c. asellus Miller [13,42]
L. c. bennettii Gray* 
L. c. californicus Gray* [13,24,42]
L. c. curti Hall 
L. c. deserticola Mearns* [13,24,42]
L. c. ememicus J. A. Allen* [24,42]
L. c. festinus Nelson [13,42]
L. c. magdalenae Nelson [13,42]
L. c. martirensis Stowell 
L. c. melanotis Mearns* [13,24,42]
L. c. merriamai Mearns* [13,42]
L. c. richardsonii Bachman* [13,24,42]
L. c. sheldoni Burt [13,42]
L. c. texianus Waterhouse* [13,24,42]
L. c. wallawalla Merriam* [13,24,42]
L. c. xanti Thomas [13,42]
*occurs north of Mexico 
Flux  noted that the number of black-tailed jackrabbit subspecies
recognized may be excessive. Using cluster analysis of anatomical
characters, Dixon and others  found that black-tailed jackrabbit
subspecies separated into two distinct groups that are geographically
separated west and east of the Colorado Rocky Mountains and the Colorado
River. They suggested only two infrataxa are warranted: the western
subspecies L. c. californicus and the eastern subspecies L. c.
Black-tailed jackrabbit and white-tailed jackrabbit (L. townsendii)
produce hybrid offspring in Utah .