Lepus callotis has three types of vocalizations. The alarm or fear reaction consists of a high-pitched scream. Another sound, emitted by males in a pair when approached by an outside intruding male, is a series of harsh grunts until the intruder leaves or is chased away. A third vocalization, consisting of a trilling grunt is heard during the sexual chase of Lepus callotis, however, it is not known which member of the pair makes this sound.
Communication Channels: acoustic ; chemical
Perception Channels: visual ; tactile ; acoustic ; chemical
Lepus callotis is considered endangered throughout its range in Mexico and southwestern New Mexico. Lepus callotis commonly comes into contact with agriculture. As a result, the overgrazing of domestic livestock may be one of the factors contributing to its decline and the apparent replacement by Lepus californicus, which has been highly adaptable to these habitat changes. Prospects for the survival of Lepus callotis in many parts of its range are considered poor.
US Federal List: endangered
CITES: no special status
IUCN Red List of Threatened Species: near threatened
Species of Lepus that live in settled areas are often considered pests because of the damage they to crops, orchards, and young forest trees. No specific adverse economic effects are noted for Lepus callotis (Grizmek 1990; Nowak 1999).
In general, various species of Lepus are used as food, and their fur may be used in manufacturing felt or for trimming gloves and other garments. No specific economic importance is noted for Lepus callotis.
Positive Impacts: food ; body parts are source of valuable material
The diet of Lepus callotis consists primarily of grasses including buffalograss, tabosagrass, fiddleneck, wolftail, blue grama, vine mesquite, ring muhly, wooly Indian wheat, and Wright buckwheat. The significant non-grass item found in their diets was sedge nutgrass.
Plant Foods: leaves; wood, bark, or stems
Primary Diet: herbivore (Folivore , Granivore )
Lepus callotis ranges from southern New Mexico to northwestern and central Mexico.
Biogeographic Regions: nearctic (Native )
Lepus callotis inhabit high plateaus at high elevations, including the grassy plains of southwestern New Mexico and the open plains of the southern Mexican tableland. They avoid hilly areas by selecting for level grassland topography with few shrubs.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: savanna or grassland
Lepus callotis body length ranges from 432 to 598 mm, tail length from 47 to 92 mm, hid foot length 118 to 141 mm, and ear length from 108 to 149 mm. The forepaws have five toes while the back paws have four. All toes end in sturdy claws. Some sexual dimorphism is present; females are generally larger than the males.
The dorsal pelage of Lepus callotis is short and coarse. The color is pale ochraceous-cinammon color heavily mixed with black. The underparts are white with traces of colored patches in front of the thighs. The tail has black hairs tipped with white on the upper surface and is all white on the underside. The sides are distinguishable from other Lepus species in that they are pure white. The rump and thighs are also white and lined with a few black hairs. A median black line concealed by sooty, brownish, and white-tipped hairs divides the rump. The limbs are white, but their outer surface is stained a buffy color. The gular pouch is also buffy while the sides of the neck and shoulders become more ochraceous in color. The head is a cream buff color, mixed with black, with whitish areas around the sides of the eyes. The ears are covered with short yellowish brown hairs that are mixed with black anteriorly and white posteriorly. The apex of the ear is white-tipped. Below the apex of the ear is a tuft of black hair. The long fringes on the anterior edge of the ear are ochraceous buff while the fringes of the tip of the ear and posterior edge are white. The inner surface of the ear is almost bare except for a dusky spot on the posterior border. The nape is ochraceous buff in color.
The winter pelage of Lepus callotis is iron gray on the rump, back, and outside of the hind legs. The front of the hind legs and the tops of the feet are white. The front of the fore legs and top of the forefeet range from a pale gray to a dull iron-gray. The median black line of the rump is not strongly distinguishable and does not extend much further than the base of the tail. The top, sides, and tip of the tail are black while the underside is two-thirds white and one-third black. The top and sides of the head and back are dark-pinkish buff overlaid with black. The nape is usually black. The ears are dark bluff, black, and white. The front border of the ears are fringed with buff or ochraceous buff hairs, and the posterior border and tip are white. The underside of the neck is dark grayish bluff and the remaining underparts, including the flanks, are white.
Range mass: 2 to 3 kg.
Range length: 432 to 598 mm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: female larger
The breeding season of Lepus callotis is a minimum of 18 weeks, occurring from mid-April to mid-August. The average number of young per litter is 2.2. The young tend to have a soft, woolly coat in early life and attain sexual maturity at a rapid rate. Breeding in Lepus does not begin within the first calendar year following their birth.
Breeding season: Breeding occurs from mid-April to mid-August.
Average number of offspring: 2.2.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous
Parental Investment: precocial
The white-sided jackrabbit (Lepus callotis), also known as the Mexican hare, is a jackrabbit found in a limited range in North America, from southern New Mexico to northwestern and central Mexico. The animal is considered threatened in New Mexico, with its numbers in decline in recent years; its presence is uncertain in Arizona.
The white-sided jackrabbit inhabits plateaus at high elevations, including the grassy plains of southwestern New Mexico and the open plains of the southern Mexican tableland. It avoids areas of hills or mountains. It prefers level lands full of grasses and also avoids areas with trees and shrubs.
The white-sided jackrabbit's body length ranges from 16 to 30 in (41 to 76 cm) long. Its tail grows to lengths of 1 to 4 in (2.5 to 10.2 cm). Its legs grow from 4 to 6 in (10 to 15 cm) in the front and the back legs can grow from 6 to 12 in (15 to 30 cm) long. The white-sided jackrabbit's ears grow 2 to 6 in (5.1 to 15.2 cm) when fully grown. The fore paws have five toes while the back paws have four. All toes end in sturdy claws. Some sexual dimorphism is present in this species; females are generally larger than the males.
The dorsal pelage of the white-sided jackrabbit is short and coarse. The color is pale cinnamon color heavily mixed with black. The underparts are white with traces of colored patches in front of the thighs. The tail has black hairs tipped with white on the upper surface and is all white on the underside. The sides are distinguishable from other species in that they are pure white, the source of their name. The rump and thighs are also white and lined with a few black hairs. A median black line concealed by sooty, brownish, and white-tipped hairs divides the rump. The limbs are white, but their outer surfaces are stained a buff color. The gular pouch is also buffy while the sides of the neck and shoulders become more ochraceous in color. The head is a cream buff color, mixed with black, with whitish areas around the sides of the eyes. The ears are covered with short yellowish-brown hairs that are mixed with black anteriorly and white posteriorly. The apex of the ear is white-tipped. Below the apex of the ear is a tuft of black hair. The long fringes on the anterior edge of the ear are ochraceous buff, while the fringes of the tip of the ear and posterior edge are white. The inner surface of the ear is almost bare except for a dusky spot on the posterior border. The nape is ochraceous buff in color.
The winter pelage of the white-sided jackrabbit is iron gray on the rump, back, and outside of the hind legs. The front of the hind legs and the tops of the feet are white. The front of the fore legs and top of the fore feet range from a pale gray to a dull iron-gray. The median black line of the rump is not strongly distinguishable and does not extend much further than the base of the tail. The top, sides, and tip of the tail are black, while the underside is two-thirds white and one-third black. The top and sides of the head and back are dark-pinkish buff overlaid with black. The nape is usually black. The ears are dark bluff, black, and white. The front border of the ears are fringed with buff or ochraceous buff hairs, and the posterior border and tip are white. The underside of the neck is dark grayish bluff and the remaining underparts, including the flanks, are white.
The breeding season of the white-sided jackrabbit is a minimum of 18 weeks, occurring from mid-April to mid-August. The average number of young per litter is around two. The young tend to have a soft, woolly coat in early life and attain sexual maturity at a rapid rate. Breeding in L. callotis does not begin within the first calendar year following its birth.
Most activity of the white-sided jackrabbit occurs during the night or at dusk, particularly on clear nights with bright moonlight. Its activity may be limited by cloud cover, precipitation, and wind, but temperature has little effect. Its escape behavior consists of alternately flashing its white sides when running away. The white-sided jackrabbit, when escaping, makes rather long, high leaps. When startled by or alarmed by a predator, it leaps straight upwards while extending the hind legs and flashing the white sides. In its resting position, a white-sided jackrabbit is camouflaged with its surroundings. The long hind legs and feet are adapted for speed, giving the animal lift and an ability to run in a zig-zag fashion that surpasses its pursuers. The long ears serve to locate sound, as well as regulate temperature when they are raised like a fan to catch passing breezes in hot conditions. The eyes, like those of most nocturnal or crepuscular animals, are laterally arranged, giving them a complete field of vision (360°). As a result, approaching danger can be perceived in advance.
A conspicuous trait of the white-sided jackrabbit is its tendency to be found in pairs, usually one male and one female. Its pair bond is most evident during the breeding season. After establishment of the pair bond, the male defends the pair from other intruding males. The purpose of such pair bonds may be to keep the sexes together in areas of low density. The members of the pair are usually within 15–20 ft of each other and run together when approached by intruders. The pair bond may not be broken during pregnancy.
The white-sided jackrabbit constructs and uses shelter forms averaging 15 in (38 cm) in length, 20 in (51 cm) in width, and 7–8 in (18–20 cm) in depth. The shelter form is usually located in clumps of grass and surrounded by dense stands of tobosa grass. The white-sided jackrabbit may also occupy underground shelters, but this behavior is rare. It forages by chewing and pulling grass blades near the ground until they are either uprooted or broken off. The food is ingested by chewing the grass sticking out of the mouth, with the head raised and the body sitting in a crouched position. The fore paws are not used in feeding except to brace against the ground as the grass is bitten off or uprooted. When eating certain nutgrass, however, the fore paws are used to excavate the bulbous tubers, leaving behind oval foraging depressions in which fecal pellets are often deposited.
The white-sided jackrabbit has three types of vocalizations. The alarm or fear reaction consists of a high-pitched scream. Another sound, emitted by males in a pair when approached by an outside intruding male, is a series of harsh grunts until the intruder leaves or is chased away. A third vocalization, consisting of a trilling grunt, is heard during the sexual chase of the white-sided jackrabbit, but it is not known which member of the pair makes this sound.
The diet of the white-sided jackrabbit consists primarily of grasses including buffalograss, tobosagrass, fiddleneck, wolftail, blue grama, vine mesquite, ring muhly, wooly Indian wheat, and Wright buckwheat. The significant nongrass item found in their diets was sedge nutgrass.
Although many species of jackrabbits and hares are considered pests because they damage crops, fields, and orchards, the white-sided jackrabbit is usually not considered a pest and has no known adverse effects on human property. Many species are also sought after for their meat and fur. This is also untrue of the white-sided jackrabbit and it is protected in most of its habitat region.
A 2011 study by the New Mexico Department of Game and Fish determined that the primary cause of decline of the white sided jackrabbit in New Mexico was due to road kill caused by nighttime US Border Patrol traffic.[3]
The white-sided jackrabbit is considered endangered throughout its range in Mexico, and is listed as threatened by New Mexico, where it occurs in the southwest, but enjoys no federal protection in the United States. A 2011 study by the state of New Mexico estimated the population to be 45 individuals. The white-sided jackrabbit commonly comes into contact with agriculture. As a result, the overgrazing of domestic livestock may be one of the factors contributing to its decline and the apparent replacement by the black-tailed jackrabbit (Lepus californicus), which has been highly adaptable to these habitat changes. Prospects for the survival of the white-sided jackrabbit in many parts of its range are considered poor at best.
The two subspecies of this jackrabbit are:
{{cite web}}: CS1 maint: archived copy as title (link) T32P2-11ApH-Traphagen.pdf (PDF), retrieved 2013-01-11
The white-sided jackrabbit (Lepus callotis), also known as the Mexican hare, is a jackrabbit found in a limited range in North America, from southern New Mexico to northwestern and central Mexico. The animal is considered threatened in New Mexico, with its numbers in decline in recent years; its presence is uncertain in Arizona.
