Currently the official IUCN Red List of Threatened Species lists 19 species of lagomorph as Threatened (IUCN categories of Critically Endangered, Endangered, or Vulnerable) out of 79 species for which complete assessments have been made (eliminating those species with Data Deficient or Not Evaluated; the IUCN/SSC Lagomorph Specialist Group has not had the opportunity to assess several new species recently described or assigned). The resulting 24% level of en-dangerment is equal to that for the class Mammalia as a whole. However, changes in assignment which are proposed, but not yet finalized, would change these numbers to 25 threatened species out of 86, or an endangerment level of 29%.

Most critical in this analysis is the level of endangerment found in those genera of lagomorphs with two or fewer species. The Lagomorpha contains seven monospecific genera and one genus with two species. Within this assemblage of the most phylogenetically unusual lagomorphs six of eight genera (75%), and seven of nine species (78%), are threatened with extinction.

Some of the most endangered mammals in the world are lagomorphs. The silver pika (Ochotona argentata) is known only from one 0.9 X 1.2 mi (1.5 X 2.0 km) patch of scrub located in the isolated Helan Shan mountains of central China. Similarly, the Ili pika (O. iliensis) lives in isolated cliffs in northwestern China, and several recent expeditions to assess its population have failed to relocate it at its type locality. Over 100 years past from the finding of Koslov's pika (O. koslowi) until it was recently rediscovered, and its habitat in central China is subject to widespread alteration. The pygmy rabbit (Brachylagus idahoensis) has declined severely throughout its range; in 2002, it disappeared from five of six known localities in the Columbia River population. The number of surviving riverine rabbits (Bunolagus monticularis) is estimated to be as low as 500 animals, its preferred habitat is disappearing, and none of its habitat is governmentally protected. Populations of the hispid hare (Caprolagus hispidus) are declining in the face of dramatic habitat loss throughout its range in Nepal and India. The Tehuantepec jackrabbit (Le-pus flavigularis) is found in only three isolated populations in southern Mexico, each with only a handful of individuals. The only striped rabbits, two Nesolagus spp., are essentially unknown. The Sumatran rabbit (N. netscheri) has only been recorded a handful of times, and the only sightings in the past several decades were on film of two individuals captured by an automatic camera-trap in 1998. The newly found (first described in 2000) Annamite rabbit (N. timminsi) is best known for being found in a market in Laos as meat; its ecology is unknown. The Amami rabbit (Pentalagus furnessi) of Japan is the world's only black rabbit. Only 3,000 individuals remain on the two islands they inhabit and are threatened by an introduced mongoose and rampant deforestation. The volcanic highlands of central Mexico surrounding Mexico City host the 6,000 remaining zachatuche (or volcano rabbits [Romero-lagus diazi]). Found on only 16 small patches of habitat, the zacatuche is being threatened by logging, burning of the zacaton grass on which it depends to enrich regrowth for cattle grazing, and thatch collection of zacaton for baskets. Only three specimens are known to science of the Omiltimi rabbit (Sylvilagus insonus) from the West Coast of Mexico, although in 1998 a barnyard dog retrieved another. Rigorous searches throughout its putative range already a protected area have failed to produce any additional sightings.

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