The Siamese crocodile (Crocodylus siamensis) is a freshwater crocodile native to Brunei, Burma, Cambodia, Laos, Thailand, Vietnam, East Malaysia, and Indonesia, (Borneo and possibly Java), . The species is highly endangered and already extirpated from many regions.
In the wild they prefer slow moving waters like swamps, rivers, and some lakes. Most adults do not exceed 3 m (10 ft) in length, although there are hybrids in captivity that can grow much larger.
Due to excessive hunting and habitat loss this crocodile is a critically endangered species. In 1992, it was believed to be extinct in the wild or very nearly so. Since then, a number of surveys have confirmed the presence of a tiny population in Thailand (possibly numbering as little as two individuals, discounting recent reintroductions), a small population in Vietnam (possibly less than 100 individuals), and more sizable populations in Burma and Laos. In March 2005, conservationists found a nest containing juvenile Siamese crocodiles in the southern Lao province of Savannakhet. There is a very small remnant population in northern Cambodia. There are no recent records from Malaysia, Brunei or Indonesia. The total wild population is estimated to be less than 5000 individuals. A number of captively held individuals are the result of hybridization with the saltwater crocodile, but several thousand "pure" individuals do exist in captivity and it is regularly bred at crocodile farms; especially in Thailand.
In the Bang Sida National Park in Thailand, near Cambodia, there is a project to reintroduce Siamese crocodile into the wild. A number of young crocodiles have been released into a small and remote river in the park, not accessible to visitors.