Mammals

These bats roost at the back of small caves or remote caverns. Group size varies from as few as 10 individuals to as many as 500, although most caves contain around 100 bats. The bats spread out across the ceiling of the caves so that they do not come into contact with one another. At dawn and dusk they leave their caves for around 20-30 minutes to forage for food. The bats primarily use echolocation to hunt small insects on the wing, although they may also glean small spiders and beetles from plant leaves. The normal foraging range appears to be limited to an area of around 1 km from the roost site. Little is known of the reproductive system of these bats. Females are believed to give birth to a single young late in the dry season (late April) each year.

Roosts in limestone caves within areas of dry evergreen or deciduous forests near rivers. Foraging occurs in nearby fields of cassava or kapok.

There are thought to be around 2,000 bats remaining in Thailand. The status of the species in Myanmar is unknown, but recent surveys indicate that this population numbers greater than 2,000.

Declining.

Classified as Endangered (EN B1+2c, C2b) on the 2006 IUCN Red List of Threatened Species.

Although the species may be locally common it has a very restricted distribution and is therefore vulnerable to a range of threats. Some populations declined following tourist disturbance of certain roost sites throughout the 1970s, collection for scientific purposes and the sale of bats as tourist souvenirs. Today, the main threat to the Thai population comes from the annual burning of forest areas near the caves. The main threats to the Myanmar population are currently unknown.

The species is protected under the Wild Animals Reservation and Protection Act (WARPA) in Thailand. The 500 km² Sai Yok National Park was created in 1980 specifically to help conserve the species. However, some populations occur outside of the park and are not protected. Very little is known about the status of the Myanmar population.

The IUCN/SSC Chiropteran Specialist Group recommends that all trade and non-essential scientific collection be prohibited and that a management policy be developed for habitats used as flight paths and foraging areas. Cave disturbances should be minimised and key roost sits protected with fences or grilles if necessary. Information on the importance of protecting the species should be made available to visitors of the National Park. The group also recommends that further research be conducted on the status, distribution and habitat requirements of the species. A monitoring programme should be developed to identify population change in relation to environmental factors. Very little is known about the Myanmar population. Further surveys are recommended to determine whether this population is an isolated relict or whether it is part of a larger population with a range that includes both Thailand and Myanmar. Some researchers have suggested that the Myanmar population might be a separate species altogether. Further molecular research is therefore required to determine the relationship between the two populations.

Bates, P.J.J., Nwe, T., Swe, K.M. and Bu, S.S.H.. 2001. Further new records of bats from Myanmar (Burma), including Craseonycteris thonglongyai Hill 1974 (Chiroptera: Craseonycteridae). Acta Chiropterologica 3(1): 33-41.

Chiroptera Specialist Group. 1996. Craseonycteris thonglongyai. In: IUCN 2006. 2006 IUCN Red List of Threatened Species. Downloaded on 09 August 2006.

Hulva, P. and Horá?ek, I. 2002. Craseonycteris thonglongyai (Chiroptera: Craseonycteridae) is a rhinolophoid: molecular evidence from cytochrome b. Acta Chiropterologica 4(2): 107-120

Hutson, A. M., Mickleburgh, S. P. and Racey, P. A. (Compilers). 2001. Microchiropteran Bats: Global Status Survey and Conservation Action Plan. IUCN/SSC Chiroptera Specialist Group. IUCN: Gland, Switzerland.

Nowak, R.M. 1999. Walker's Mammals of the World. Sixth edition. The Johns Hopkins University Press, Baltimore and London.

Distribution map based on data provided by the IUCN Global Mammal Assessment.