Siamese freshwater crocodile, Soft-belly, Singapore small-grain, Crocodile du Siam, Cocodrilo de Siam, Buaja, Jara Kaenumchued, Buaya kodok
The Siamese crocodile is a freshwater crocodilian (a group of animals that includes alligators, caimans and gharials), which is small with a fairly wide, smooth snout and a raised bony crest behind each of its eyes. It is native to regions in South-East Asia. It is amongst the most endangered crocodiles that live in the wild, although there are many of them in captivity. The only individuals in the wild seem to be in the Mekong River basin and the wetlands in Cambodia, and these populations are depleted and fragmented due to hunting, habitat alteration and human disturbance.
The historic range of this species included the greater part of Southeast Asia (Cambodia; Indonesia; Laos; Thailand). It is now extinct or nearly extinct in the wild in most countries except Cambodia. It occurs in a wide variety of freshwater habitats, including lakes, seasonal oxbow lakes, slow-moving streams and rivers, marshes and swamplands.
There is very little information about this species’ natural history in the wild. The adults are territorial, marking their territory by slapping their head loudly down onto the water and snapping their jaws on the water’s surface. Dominant animals swim typically higher in the water, and others of the same species signal submission by means of swimming lower down in the water. Dominant individuals control access to food, mates, and the best sites, for nesting, basking, and living. Crocodiles communicate with sounds, movement, postures, touch, and odors released by their four scent glands. Young will call to adults when they are in danger, and are also very vocal while they are being fed. Adults most commonly make a loud, low, repeated roar, which may be repeated by other adults. When it is hunting mammals, a crocodile will wait near the edge of the water with just the tip of its snout and its eyes above the water. As an animal approaches to drink, the crocodile suddenly attacks, dragging its prey down under the water, where it drowns and is eaten.
Little is known about the mating system of Siamese crocodiles. However, the usual crocodilian breeding system is one of polygyny. This means that one male mates with more than one female. Breeding is during April and May, the time of the wet season. The female lays 20 to 50 eggs in a mound nest and then guards them. The eggs hatch after about 80 days, when the mother opens the nest and carries the hatchlings in her jaws to the water. It is unknown whether parental care is given after hatching. In captivity Siamese crocodiles will gain reproductive maturity at about 10 years old, but it is unknown whether this is also true in the wild.
The main threats to this species come from the destruction of their habitat and from hunting, their skin being highly valuable. Sustainable harvesting could be an incentive to protect their habitat and therefore the species, as the hides bring a high price on the market. Thousands of these animals are harvested in crocodile farms or bred in captivity, especially in Thailand and Cambodia.
According to the IUCN Red List, the total Siamese crocodile population size is around 500-1000 mature individuals. According to the World Wide Fund for Nature (also known as World Wildlife Fund), there may be around 100-300 wild adults in Cambodia. Overall, currently Siamese crocodiles are classified as Critically Endangered (CR) and their numbers today are decreasing.