Tehuantepec jackrabbit  (Lepus flavigularis)

Classified as Endangered (EN) on the IUCN Red List (1).

The Tehuantepec jackrabbit is the most endangered hare species in the world (2) (5) (6), and, like other hares (Lepus spp.), is recognised by its long legs, large hind feet and huge ears (2) (7) (8), which can measure up to 12 centimetres in length (2). The hair is coarse (2), and the feet are well furred (7). The upperparts of the body are a rich ochraceous buff, washed through with black, and the back of the neck bears a buffy stripe, which separates two narrow, black stripes that extend backwards from the base of each ear. The ears are buff coloured, with whitish tips, while the throat is yellowish and the underparts and flanks are white. The legs and rump are pale whitish to grey, and the tail is grey below and black above (2) (5). In spring, the fur may become more worn, with the upperparts faded to a more yellowish colour and the black stripes on the neck visible only as black patches behind the ears (2).

The Tehuantepec jackrabbit may show some variation across its range, with individuals from Santa María del Mar significantly larger than, and genetically distinct from, those in other areas (3) (9). The Tehuantepec jackrabbit is similar in appearance to the white-sided jackrabbit, Lepus callotis, but the latter has larger ears and lacks the distinctive neck colouration of this species (2).

The Tehuantepec jackrabbit has the most southerly distribution of any Lepus species in North America (2), being restricted to southern Mexico, around the Gulf of Tehuantepec (2) (5) (7) (8). Thought to have once occurred from Salina Cruz, in the state of Oaxaca, to the extreme west of the state of Chiapas (2) (5), it may now exist only in Oaxaca (1).

This species inhabits grassland with scattered shrub and tree cover, shrub forest, and coastal grassy dunes which never exceed a four to five kilometre wide strip along the shores of salt water lagoons (1) (2) (4) (5) (10). It is not found above elevations of about 500 metres (1).

The Tehuantepec jackrabbit is most active at night or at dawn and dusk (1) (2) (5) (7) (8), resting under cover during the day (4) (10). Like most other hares, it does not dig burrows, but instead relies on camouflage and its strong running ability to escape danger. The diet is likely to consist of grass and other vegetation, although twigs, barks and cultivated plants may possibly be taken if other alternatives are unavailable (7) (8).

Tehuantepec jackrabbits occupy overlapping home ranges, and are believed to be non-territorial and to have a polygamous mating system (4) (11) (12). The lengthy breeding season may last from February to December, peaking during the rainy season between May and October (1) (12). Average litter size is two (1). As in other hares, the young, known as leverets, are born in an open place and are well developed at birth, being fully furred, with the eyes open, and able to move about shortly after birth. The female leaves the young concealed in dense vegetation, visiting to nurse them for perhaps only one brief period each day (7) (8). Young hares may be weaned in as little as 17 to 23 days (8), and in this species reach maturity at six to seven months, with individuals capable of breeding in the first year of life (1) (4).

The Tehuantepec jackrabbit has a small and declining range, and is now found in only four small and isolated populations, with a total population size estimated at fewer than 1,000 individuals (1) (6). The main threats to the species are habitat loss and hunting, with grasslands converted to agriculture, pasture or settlement, or degraded by human-induced fires and introduced grasses, and with hares shot for sport (1) (2) (5) (7). The species is also hunted for food, and conservation laws are not being enforced (6). Low genetic variation in the tiny remaining population may pose an additional threat (1), potentially leading to inbreeding.

The Tehuantepec jackrabbit is listed as Critically Endangered by the Mexican government (1) (13), but conservation laws are not well enforced by local authorities (1), and the areas the species inhabits are unprotected (10). Effective protection of the species’ habitat is urgently needed, together with the preservation of its natural structure and diversity (4) (10). Other recommended conservation actions for the Tehuantepec jackrabbit include better regulation of hunting, further research into the species, captive breeding, education programmes (2), and further surveys to clarify the extent of its distribution (14). It may also be important to recognise and manage the genetically distinct populations as individual units, in order to avoid further loss of genetic diversity in this highly endangered species (9).

View information on this species at the UNEP World Conservation Monitoring Centre.

To find out more about the Tehuantepec jackrabbit and its conservation see:

• Cervantes, F.A. (1993) Lepus flavigularis. Mammalian Species, 423: 1-3. Available at:
  http://www.science.smith.edu/departments/Biology/VHAYSSEN/msi/pdf/i0076-3519-423-01-0001.pdf
• Chapman, J.A. and Flux, J.E.C. (1990) Rabbits, Hares and Pikas: Status Survey and Conservation Action Plan. IUCN/SSC Lagomorph Specialist Group, IUCN, Gland. Available at:
  http://data.iucn.org/dbtw-wpd/edocs/1990-010.pdf

For more information on the conservation of hares and rabbits see:

• IUCN/SSC Lagomorph Specialist Group:
  http://www.ualberta.ca/~dhik/lsg/INDEX.HTM
• World Lagomorph Society:
  http://www.worldlagomorphsociety.org/