Long-tailed climbing mouse  (Vandeleuria nilagirica)

The long-tailed climbing mouse is classified as Endangered (EN) on the IUCN Red List (1).

Adapted to a life high in the canopy, the long-tailed climbing mouse (Vandeleuria nilagirica) has a long prehensile tail that acts as a balancing aid, and an opposable digit on the hands and feet that is used to grasp to branches whilst climbing (2) (3). In common with other Vandeleuria climbing mice, the fur is soft and silky, and highly variable in colour, ranging from pale, dull brown to dark, reddish brown. The long-tailed climbing mouse is very similar in appearance to the Asiatic long-tailed climbing mouse (V. oleracea), and indeed was once considered a subspecies of its more widespread congener, but is distinguished by a substantially longer tail and greyer underparts (3) (4).

The long-tailed climbing mouse is endemic to the northern Western Ghats of India. It is primarily found in the districts of Coorg and Nilgiris, although the only known sizeable population is at Haleri in Coorg (1).

The long-tailed climbing mouse is found in montane evergreen forests and relatively undisturbed plantations of coffee, banana and cardamom, providing there is a canopy of native tree species (1).

A highly arboreal and active species, at night the long-tailed climbing mouse runs along branches and twigs, even climbing vertical shoots, to forage for a variety of fruits and buds (1) (2). Whilst feeding, this diminutive species may loosely wind its long tail around a branch as a balancing aid, or hang from it to reach food sources on fragile twigs (1) (2) (3). During the day the long-tailed climbing mouse seeks shelter in tree holes or nests high up in the canopy. Pairs nest between October and February and will descend to the ground to collect grass and leaves to construct a shallow, oval shaped nest in the fork of a tree (1) (2). As is typical of many small mice species, three or four young are born after a gestation period of 20 to 30 days, with a life expectancy of little more than one year (2) (5).

Occupying an area no more than 500 square kilometres, the long-tailed climbing mouse is threatened by the loss and degradation of its habitat (1). Changes in forestry management, with the increasing use of pesticides and native tree canopy species being replaced with exotics, has resulted in forest fragmentation and gaps in the canopy (1) (3). Coffee plantations have also been felled and replaced with ginger cultivation (3). Consequently, many populations of the long-tailed climbing mouse have been left isolated, greatly increasing the species extinction risk (1).

There are currently no conservation measures in place for the long-tailed climbing mouse, and it is not known to occur in any protected areas. However, further surveys in the Brahmagiri and Pushpagiri Wildlife Sanctuaries may find additional populations. This Endangered species will also benefit from further studies into its distribution, ecology and population status (1).

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

For more information on the conservation of the Western Ghats, India:

• WWF:
  http://wwf.panda.org/what_we_do/where_we_work/western_ghats/
• Wildlife Conservation Society:
  http://www.wcs.org/saving-wild-places/asia/western-ghats-india.aspx