Tehuantepec Jackrabbit

Taxobox
name = Tehuantepec JackrabbitMSW3 Hoffmann | pages = 199]
status = EN | status_system = IUCN2.3
status_ref = IUCN2006 | assessors = Lagomorph Specialist Group | year = 1996 | title = Lepus flavigularis | id = 11790 | downloaded = 2006-12-25]
regnum = Animalia
phylum = Chordata
classis = Mammalia
ordo = Lagomorpha
familia = Leporidae
genus = "Lepus"
species = "L. flavigularis"
binomial = "Lepus flavigularis"
binomial_authority = Wagner, 1844

The Tehuantepec Jackrabbit ("Lepus flavigularis") is easily distinguished from other species of jackrabbits by two black stripes that run from the base of the ears to the nape, and by its white flanks.cite book | author = Flux, J. E. C., and R. Angermann | year = 1990 | chapter = The hares and jackrabbits | pages = Pp. 61-94 | title = Rabbits, hares, and pikas. Status survey and conservation action plan | editor = Chapman, J. A. and J. E. C. Flux, eds. | publisher = International Union for Conservation of Nature and Natural Resources | location = Gland, Switzerland] Underparts are white, upperparts are bright-brown washed with black, rump is gray, and the tail is black. This leporid is one of the largest jackrabbits and has large ears and legs. Adults weigh about 3500 to 4000 grams.

Distribution

The Tehuantepec Jackrabbit is a rare endemic of Oaxaca, México, and is only found along savannas and grassy dunes on the shores of a salt water lagoon connected to the Gulf of Tehuantepec. Three small populations persist isolated from each other.

The former distribution of the Tehuantepec Jackrabbit is not documented in detail, but it is estimated that the leporid's historic geographic range along the Mexican Pacific Coast on the Isthmus of Tehuantepec from Salina Cruz in Oaxaca to Tonalá in Chiapas, an area of perhaps only 5000 km sq.cite journal | author = Nelson, E. W. | year = 1909 | title = The rabbits of North America | journal = North American Fauna | volume = 29 | pages = 9–287]

Habitat and Ecology

Tropical dry savannas dominated by native grasses ("Bouteloua", "Paspalum") with an overstory of sparse bushes of nanche ("Byrsonima crassifolia"), and scattered trees of morro ("Crescentia") are selected by the Tehuantepec Jackrabbit.Farías, V. 2004. Spatio-temporal ecology and habitat selection of the critically endangered tropical hare ("Lepus flavigularis") in Oaxaca, Mexico. Ph.D. Dissertation. University of Massachusetts, Amherst.] The Tehuantepec Jackrabbit is also found in coastal grassy dunes with "Opuntia decumbens", "Opuntia tehuantepecana", and "Sabal mexicana".cite journal | author = Vargas, J. | year = 2000 | title = Distribución, abundancia y hábitat de la liebre endémica "Lepus flavigularis" (Mammalia: Lagomorpha) | journal = Tesis de Maestría en Biología Animal, Facultad de Ciencias, Universidad Nacional Autónoma de México. México, D. F., México.]

Home ranges overlap with one or more individuals regardless of sex and age, and home range size is about 50 ha with core areas of 9 ha for adult jackrabbits. The Tehuantepec Jackrabbit is nocturnal and crepuscular, and during the diurnal hours it rests in forms under bushes or grasses.

Native mammals that coexist with the Tehuantepec Jackrabbit are the Eastern Cottontail ("Sylvilagus floridanus"), the Nine-banded Armadillo ("Dasypus novemcinctus"), the Hooded and Western Hog-nosed Skunks ("Mephitis macroura", "Conepatus mesoleucus"), the Virginia Opossum ("Didelphis marsupialis"), the Gray Mouse Opossum ("Tlacuatzin canescens"), the Gray Fox ("Urocyon cinereoargenteus"), the Common Raccoon ("Procyon lotor"), and the Coyote ("Canis latrans").cite journal | author = Cervantes, F. A., and L. Yépez | year = 1995 | title = Species richness of mammals from the vicinity of Salina Cruz, coastal Oaxaca, Mexico | journal = Anales del Instituto de Biología Universidad Nacional Autónoma de México, Serie Zoología | volume = 66 | pages = 113–122] Of these, the Gray Fox and the Coyote are native predators of the Tehuantepec Jackrabbit.

Reproduction

The length of the breeding season may extend from February to December, with a peak in reproduction during the rainy season (from May to October). Litter size is one to four embryos,cite journal | author = Cervantes, F. A. | year = 1993 | title = "Lepus flavigularis" | journal = Mammalian Species | volume = 423 | pages = 1–3 | doi = 10.2307/3504288] but the number of litters produced per female per year remains to be investigated.

Conservation

The Tehuantepec Jackrabbit is listed as critically endangered in the Mexican Official Norm NOM-059-ECOL-2001, and as an endangered species by the International Union for the Conservation of Nature (IUCN) Red List of Endangered Species.

Threats

The Tehuantepec Jackrabbit is jeopardized by habitat loss and fragmentation, poaching, small population size, and genetic isolation. Introduction of exotic grasses, frequent and induced fires, agricultural and cattle-raising activities, and human settlements are deteriorating the floristic diversity and native vegetation structure in savannas inhabited by Tehuantepec jackrabbits.cite journal | author = Pérez-García, E. A., J. Meave, and C. Gallardo | year = 2001 | title = Vegetación y Flora de la Región de Nizanda, Istmo de Tehuatnepec, Oaxaca, México | journal = Acta Botánica Mexicana | volume = 56 | pages = 19–88] Locally, the Tehuantepec Jackrabbit is taken occasionally as subsistence hunting, and very occasionally as pets in rural communities. Predation by the Gray Fox and the Coyote is the major cause of mortality of the Tehuantepec Jackrabbit. However, poachers may come from nearby cities and decimate populations in a few nights of hunting.

References

*Cervantes, F. A., and C. Lorenzo. 1997. Morphometric differentiation of rabbits ("Sylvilagus" and "Romerolagus") and jackrabbits ("Lepus") of Mexico. Gibier Faune Sauvage 14:405-425.
*Sántis, E. C. 2002. Distribución y abundancia de la liebre endémica "Lepus flavigularis" y el conejo castellano "Sylvilagus floridanus" (Mammalia: Lagomorpha) en el Istmo de Tehuantepec, Oaxaca, México. Tesis de Licenciado en Biología. Universidad de Ciencias y Artes de Chiapas. Tuxtla Gutierrez, Chiapas, México.
*Vargas, Z. 2001. Valoración de los vertebrados terrestres por los huaves y zapotecas de la zona lagunar del Istmo de Tehuantepec, Oaxaca. Tesis de Maestría. El Colegio de la Frontera Sur. Chiapas, México.
*Villa, B., and F. A. Cervantes. 2003. Los mamíferos de México. Iberoamericana. Instituto de Biología, Universidad Nacional Autónoma de México. México, D. F. 140 pp. and CD-rom.