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Liebre torda (Lepus callotis)
N omb res comu n es: Liebre (Español) / White-sided Jackrabbit (Inglés)
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Description 1
The White-sided Jackrabbit strongly prefers level ground to hills, and does not require shrubs for cover,
but uses clumps or dense stands of grass instead. Grass also makes up more than 99 percent of its
diet. Livestock grazing of native grasses most likely has contributed to the decline of this species. Whitesided Jackrabbits tend to form male-female pairs, and the male will defend the pair from other males.
The breeding season of the White-sided Jackrabbit runs from mid-April to mid-August. There are one to
four offspring (usually two) in a litter. Predators include eagles, hawks, owls, foxes, and coyotes.
Links:
Mammal Species of the World
Click here for The American Society of Mammalogists species account
Range description 2,3
Lepus callotis is nearly endemic to Mexico, distributed from southwestern New Mexico (USA) to
northern Oaxaca (Mexico) (Hall 1981, Best and Henry 1993, Villa-Ramirez and Cervantes 2003). L. callotis
has been observed at an elevation of 2,550 m in Puebla and 750 m in Morelos (Best and Henry 1993). L.
c. gaillardi has a discontinuous distribution that extends from southwestern New Mexico, USA to northcentral Durango, Mexico (Best and Henry 1993). In Mexico, there are two isolated populations, one in
central Chihuahua and the other extending from south-central Chihuahua into Durango (MartinezVilleda 2006). Its distribution in southwestern New Mexico is restricted to two locations in Hidalgo
County at elevations between 1,500-1,600 m (Flux and Angermann 1990). In 1950, there was a potential
sighting of two L. c. gaillardi on the west side of the Huachuca Mountains in Arizona (Hoffmeister1986).
The total range in the USA is estimated to be 120 km (Bednarz and Cook 1984). L. c. callotis is
distributed from the central part of east Durango toward the plains of the central part of Mexico, along
the axis Neovolcanic to northern Guerrero and Oaxaca (Best and Henry 1993, Villa-Ramirez and
Cervantes 2003).
Morphology 4,5
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.
R an ge mass: 2 to 3 kg.
R an ge l en gth : 432 to 598 mm.
Oth er Ph ysi cal Featu res: endothermic ; homoiothermic; bilateral symmetry
Sexu al Di morp h i sm: female larger
Size 6
Len gth : 56 cm
Diagnostic description 6
Lepus alleni is larger (total length 553-670 mm), with longer ears (more than 130 mm) (Hoffmeister 1986,
Whitaker 1996).
I dnature guides 7
Identification key for mammals of North America
Habitat and ecology 2,3
Hab i tat an d Ecol ogy
L. callotis is restricted to high grasslands in New Mexico (Flux and Angermann 1990). In the area
surrounding the valleys inhabited by this species, overgrazing has caused the presence of shrub to
increase, resulting in the increase of Lepus californicus and exclusion of L. callotis (Bednarz and Cook
1984). This problem has been identified in parts of Mexico, as well (Best and Henry 1993). In Zacatecas
(Mexico) it lives in plains of open grasslands. In Queretaro (Mexico) it is associated with cultivated areas
and corrals (potreros).
Breeding season varies from the middle of April to August and the average litter size is 2.2 (range 1-4)
(Anderson 1972; Bogan and Jones 1975; Bednarz 1977). L. callotis is capable of producing at least three
litters per year during the breeding season (Bednarz 1977). It is common to observe individuals in pairs,
particularly in the breeding season. L. callotis is strictly nocturnal (Flux and Angermann 1990). An
average total length for this species is 55.0 cm (Best and Henry 1993). Their diet is almost exclusively
grasses, but may consist of roots during dry seasons (Bednarz 1977).
Systems
Terrestrial
Migration 6
N on -M i gran t : Yes. At least some populations of this species do not make significant seasonal
migrations. Juvenile dispersal is not considered a migration.
Local l y M i gran t : 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).
Local l y M i gran t : No. No populations of this species make annual migrations of over 200 km.
Trophic strategy 4,5
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.
Pl an t Food s: leaves; wood, bark, or stems
Pri mary Di et: herbivore (Folivore , Granivore )
Number of occurrences 6
Note: For many non-migratory species, occurrences are roughly equivalent to populations.
Esti mated N u mb er of Occu rren ces : 21 - 80
Commen ts : The number of extant, viable occurrences is unknown but probably falls between 20 and
100. Anderson and Gaunt (1962) mapped 45 Mexican localities represented by 131 museum specimens.
In New Mexico, the total range encompasses about 120 sq km, which might comprise two distinct
occurrences (Bednarz and Cook 1984). Anderson (1972) mapped 11 localities in Chihuahua but did not
comment on current status in these areas; Baker (1977) and Findley and Caire (1977) regarded the
status in Chihuahua as poor. Davis and Lukens (1958) stated that this species was widespread in the
central tablelands of southern Mexico, implying a large number of historical occurrences.
Ecology 6
Most often observed in pairs. In New Mexico, average density is 1/32 ha (see Best and Henry 1993).
Behaviour 4,5
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.
Commu n i cati on Ch an n el s: acoustic ; chemical
Percep ti on Ch an n el s: visual ; tactile ; acoustic ; chemical
Cyclicity 6
Commen ts : Appears to be nocturnal/crepuscular. Rests in cover during the day. Cloud cover,
precipitation, and wind inhibit activity.
Reproduction 4,5
The breeding season of Lepus callotis is a minimum of 18 weeks, occurring from mid-April to midAugust. 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.
Breed i n g season : Breeding occurs from mid-April to mid-August.
Average n u mb er of offsp ri n g: 2.2.
K ey R ep rod u cti ve Featu res: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious
(sexes separate); sexual ; viviparous
Paren tal In vestmen t: precocial
Statistics of barcoding coverage: lepus callotis 8
Barcode of Life Data Systems (BOLDS) Stats
Public Records: 0
Specimens with Barcodes: 3
Species With Barcodes: 1
Iucn red list assessment 2,3
R ed Li st Category
NT
Near Threatened
R ed Li st Cri teri a
Versi on
3.1
Year Assessed
2008
Assessor/s
Mexican Association for Conservation and Study of Lagomorphs (AMCELA), Romero Malpica, F.J. & Rangel
Cordero, H.
R evi ewer/s
Smith, A.T. & Johnston, C.H. (Lagomorph Red List Authority)
Con tri b u tor/s
Ju sti fi cati on
Lepus callotis is a widespread species. There is a general lack of data regarding current population
status in Mexico, the bulk of its distribution. There are reports of declines for the isolated population in
New Mexico and in Durango, Mexico (Flux and Angermann 1990, Best and Henry 1993). L. callotis was
listed as threatened by the New Mexico Department of Game and Fish in 1975 and remains at that
threat status (New Mexico Department of Game and Fish 2006). Furthermore, habitat changes preferred
by L. californicus have led to the exclusion of L. callotis in several areas (Bednarz and Cook 1984; Best
and Henry 1993). It is inferred that this will only exacerbate the issue of population decline. Therefore,
efforts to determine population decline should be implemented, as this species may qualify for listing
as Vulnerable under criteria A2abce or A3bce.
Hi story
1996
Lower Risk/near threatened (LR/nt)
1994
Indeterminate (I)
Conservation status 4,5
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 Fed eral Li st: endangered
CITES: no special status
IUCN R ed Li st of Th reaten ed Sp eci es: near threatened
Population 2,3
Pop u l ati on
In 1976, the density of L. callotis was estimated at 1/31.6 ha in New Mexico, producing a maximum
population of 340 hares (Bednarz 1977). Between 1976 and 1981, the restricted population in New
Mexico has experienced a nearly 50% decline due to habitat change (Flux and Angermann 1990). This
decline has been accompanied by an increase in the presence of L. californicus and Sylvilagus
audubonii (Best and Henry 1993).
Population information for Mexico is scarce (Flux and Angermann 1990). There has been an observed
decline in population numbers for Durango (Best and Henry 1993). A survey conducted from 1998-1999
on the semi-desert and plains grasslands habitats in Chihuahua, Mexico determined L. callotis densities
of 0.01/ha and 0.06/ha, respectively (Desmond 2004).
Pop u l ati on Tren d
Decreasing
Threats 2,3
M aj or Th reats
Changes in habitat due to overgrazing negatively impact L. callotis resulting in L. californicus
encroachment (Flux and Angermann 1990, Desmond 2004). In some places, there is competition with L.
californicus. Additional threats are hunting for sport and local subsistence, human perturbation and
exotic predation. In some places the animal competition (livestock), habitat fragmentation and humaninduced fires represent important threats for their populations. A model generated for climate
conditions in 2050 indicated a 60% range reduction from the current potential range for this species
(Martinez-Villeda 2006).
Conservation actions 2,3
Con servati on Acti on s
Research should be concentrated on determining population numbers and range, as well as efforts to
establish trends and monitoring. Population decline in New Mexico prompted the listing of L. callotis as
threatened in 1975 by New Mexico Department of Game and Fish (New Mexico Department of Game
and Fish 2006). Efforts have been made to monitor population status and trends in New Mexico, as well
as, encouraging shrub control and non-detrimental grazing practices by local landowners within L.
callotis habitat (New Mexico Department of Game and Fish 2006). Range reduction, indicated by climate
change models, is expected to be more severe in the northern portion of this species' range. Is it
suggested that assessments be made of the population density of L. c. gaillardi and habitat
transformation, to determine that impact future changes will have on its survival (Martinez-Villeda
2006).
Uses 4,5
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).
Taxonomy 6
Commen ts : Anderson and Gaunt (1962) examined morphological variation in the white-sided
jackrabbits of Mexico and concluded that " Lepus gaillardi " intergrades with and is conspecific with
Lepus callotis. These authors accorded subspecific status to gaillardi , but their data reveal wide overlap
between the gaillardi and callotis in certain characteristics, instances of clinal variation within
subspecies callotis (with an end of the cline not significantly different from the condition of subspecies
gaillardi ), and not very strong geographic concordance in the pattern of variation in several characters.
Considering the lack of genetic data and the lack of a strong geographic pattern in the morphological
data, the evolutionary significance of the named subspecies is uncertain. Hoffmann and Smith (in
Wilson and Reeder 2005) recognized gaillardi as a valid subspecies.
" Lepus mexicanus" is a synonym of Lepus callotis (Anderson and Gaunt 1962).
Gonzalez and Cervantes (1996) found that Lepus callotis from Michoacan differs chromosomally from
Lepus alleni , L. flavigularis, and L. californicus. Based on cranial characteristics, Dixon et al. (1983) found
that Lepus callotis is easily differentiated from L. flavigularis. However, cranial data leave open to
question the taxonomic relationship between Lepus callotis and the Mexican subspecies of L.
californicus (Dixon et al. 1983).
Cervantes and Lorenzo (1997, not seen) examined morphometric differentiation of lagomorphs in
Mexico.
References
1. © Smithsonian Institution, some rights reserved
2. Mexican Association for Conservation and Study of Lagomorphs (AMCELA), Romero Malpica, F.J. &
Rangel Cordero, H. 2008. Lepus callotis. In: IUCN 2014 . IUCN Red List of Threatened Species.
Version 2014.1 . <www.iucnredlist.org>
3. © International Union for Conservation of Nature and Natural Resources, some rights reserved
4. Dharmani, A. 2000. "Lepus callotis" (On-line), Animal Diversity Web. Accessed April 27, 2013 at
http://animaldiversity.ummz.umich.edu/site/accounts/information/Lepus_callotis.html
5. © The Regents of the University of Michigan and its licensors, some rights reserved
6. © NatureServe, some rights reserved
7. © Discover Life and original sources, some rights reserved
8. © Barcode of Life Data Systems, some rights reserved