Siamese crocodile  (Crocodylus siamensis)

Classified as Critically Endangered (CR) on the IUCN Red List (1), and listed on Appendix I of CITES (3).

The Siamese crocodile is a small, freshwater crocodilian (a group that also includes alligators, caimans and the gharial), with a relatively broad, smooth snout and an elevated bony crest behind each eye (4). It is one of the most endangered crocodiles in the wild, although it is extensively bred in captivity (5).

Previously found throughout South East Asia but now extinct, or nearly extinct, from most countries except Cambodia (2).

The Siamese crocodile occurs along rainforest rivers and in adjacent swamps or lagoons (4).

Adults feed mainly on fish but may also eat amphibians, reptiles and small mammals (2). Very little else is known about the natural history of this species in the wild, but females do appear to build mound-nests constructed from scraped-up plant debris mixed with mud (4). In captivity, these crocodiles breed during the wet season (April to May), laying between 20 and 50 eggs which are then guarded until they hatch (5). After incubation, the female will assist her young as they break out of their eggs and then carry the hatchlings to the water in her jaws (6).

Siamese crocodiles are under threat from human disturbance and habitat occupation, which is forcing remaining populations to the edges of their former range (5). The conversion of rainforest habitat to agricultural use along with aggressive hunting for crocodile skins, have contributed to the decline of this species of crocodile (5). In Cambodia, which is the species' last remaining stronghold, incursion into pristine habitat is now occurring through aid development programs, and the hunting of adult females for crocodile farm stock is reported to be widespread (2).

Until recently, very little data existed on Siamese crocodile numbers and distribution, a factor which led to the species being reported as virtually extinct in the wild in 1992 (5). Since then a large amount of research has been conducted and this has shown a slightly more encouraging picture, although the status is still hard to judge. Siamese crocodiles appear to be mainly found in Cambodia where updated estimates suggest a population of no greater than 5,000 individuals (2), though it may be considerably less (5). However, the species is extensively maintained and bred in captivity, in both Thailand and Cambodia, where it is farmed for the commercial value of its skins (2). The species is considered relatively inoffensive to humans, making restocking programmes a distinct possibility provided sufficient habitat is maintained and protected. Local people have been reported to protect crocodiles, which they view to be sacred (2). Programs are already underway in Thailand (2) and, although the future of the Siamese crocodile remains in the balance, there is more optimism than a decade ago.

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

To find out more about the Siamese crocodile and about the conservation of crocodilians visit:

• IUCN SSC Crocodile Specialist Group:
  http://iucncsg.org
• Crocodilian.com:
  http://crocodilian.com/
• Detailed range map for the Siamese crocodile:
  http://www.flmnh.ufl.edu/cnhc/cst_csia_dh_map.htm