Crocodylus siamensis along the Sre Ambel river, southern Cambodia: habitat, nesting, and conservation

Abstract

We investigated the conservation status of the endangered Siamese crocodile (Crocodylus siamensis) along the Sre Ambel River in southern Cambodia from 2000-2002. The Sre Ambel River drains much of southwestern Cambodia before flowing into Kampong Saom Bay. Extensive, heavily vegetated wetlands and oxbow lakes characterize the floodplain. A combination of daylight surveys and nocturnal spotlight surveys were used to assess the distribution and status of crocodile populations in this region. We verified the occurrence of C. siamensis at six sites based on observations of crocodiles, the presence of tracks and scat, evidence of nesting, and a fresh skeleton obtained in a village. Crocodiles are uncommon in the main river channel, and seem to prefer oxbow lakes with floating mats of vegetation and permanent freshwater marshes. Observations of nesting activity suggest that most clutches are deposited during the late dry season (March-April) in nest mounds composed of soil and vegetation, and hatchlings emerge at the beginning of the wet season (June-July). The long-term viability of the C. siamensis population along the Sre Ambel River is doubtful owing to the widespread collection of living crocodiles to stock breeding farms; other crocodiles are taken incidental to fishing activities.