Lion-tailed macaque  (Macaca silenus)

Classified as Endangered (EN - B1+2c, C2a) on the IUCN Red List 2002 (1), and listed on Appendix I of CITES (3).

The striking lion-tailed macaque is one of the smallest and most endangered of the macaque species of monkey (4). The coat is shiny and black apart from an impressive mane of grey hair framing the face (5). The common name refers to the long, thin naked lion-like tail with a tuft of black fur on the end (5). The sexes are similar in appearance, although males are larger in size and have prominent canines (4).

Found in the Western Ghats Mountains of southwest India (5).

Inhabits evergreen broadleaf monsoon forest (6).

Lion-tailed macaques live in small groups of between 4 – 30 (average 10 and 20) members, which are usually composed of a single male, several females and their young, but occasionally up to three adult males are seen (2) (5). These macaques spend the majority of their time in the trees, huddling together to sleep at night high up in the forest canopy (4). There is no specific breeding season; females that are ready to mate have small swellings in the region under their tail at oestrous, which the male examines (2) (4). Females give birth to a single offspring after a gestation period of around 6 months (162 – 186 days) (2) (5). Males tend to leave their natal group once they reach maturity and live in bachelor groups (5), whereas females remain, fitting into the hierarchy that exists (6). Groups are territorial and males of this species are the only macaques that use calls to denote territorial boundaries (5).

The mainstay of the lion-tailed macaque diet is fruit, although they will also forage for seeds, young leaves, flowers, buds and even fungi (4). Their distensible cheek pouches are used to quickly gather large amounts of food and when fully extended have the same capacity as their stomach (5).

Lion-tailed macaques are increasingly rare, mainly as a result of the destruction of their forest home. Only 1% of the original habitat remains today due to widespread deforestation for timber, agriculture and development (4). This species persists in isolated pockets of remaining forest, which can lead to inbreeding depression, thus further threatening their precarious status (5). Additional threats come from hunting; they may be persecuted as crop pests and are often mistaken for Nilgiri langurs (Semnopithecus johnii) whose meat is erroneously believed to have medicinal properties (2) (4).

This species is one of the most endangered macaques in the world (4). International trade is banned by their listing on Appendix I of the International Convention on Trade in Endangered Species (CITES) and they are also protected by Indian law (7). Lion-tailed macaques are found in at least 21 protected areas (2), but they are the subject of few studies or conservation programmes (4). A large captive population has been developed in American and European zoos as part of a Species Survival Plan (SSP) and this population has the potential to be used in reintroductions should this become necessary (2).

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

Further information on this species is available from:

• Smithsonian National Zoological Park:
  http://nationalzoo.si.edu/Animals/AsiaTrail/lionmacaque.cfm