Friday, February 22, 2013

Crocodilians (Phylum Chordata: Order Crocodilia) of Singapore

Crocodilians (phylum Chordata, subphylum Vertebrata, superclass Tetrapoda, class Reptilia, order Crocodilia) are semi-aquatic reptiles with a long snout, short limbs with webbed feet, and a muscular, laterally compressed tail. They have large and powerful jaws with conical teeth, allowing them to effectively hunt for fish and other animals. They are good swimmers, and have a special eyelid-like membrane which covers the eye when they are underwater. Their body is covered in tough and leathery plate-like scales. Crocodilians usually lay their eggs in nests constructed of vegetation on land, guarded by the female.

Like most other reptiles, they have limited physiological means to maintain the body temperature within a narrow range, and are more reliant on external heat sources. Like other vertebrates, they have a backbone with a spinal cord (a hollow tube of nervous tissue).

Estuarine Crocodile (Crocodylus porosus)
The Estuarine Crocodile (Crocodylus porosus) is the only crocodilian that has been confirmed to occur in Singapore. This is the largest living species of reptile in the world, with reports suggesting that it can grow up to 9m long. Most of the ones seen are much smaller though. In Singapore, they are occasionally seen in mangrove forests, estuaries and reservoirs, and the ones sighted are not more than 3m long. They mostly hunt for fish and other small animals at night. In the day, they can be seen basking in the sun at the water's edge, or hiding among vegetation.

Estuarine Crocodile (Crocodylus porosus)
Estuarine Crocodiles have a long and relatively broad snout. The body is usually yellow, olive or greyish above with black checker-spots, while the underside is white. They start breeding when they are about 3m long. Crocodile nests constructed of vegetation has been discovered in our mangrove forests before, and young crocodiles have also been sighted.

  • Baker, N. 2013. Ecology Asia. Retrieved Feb 22, 2013, from
  • Baker, N. & K. Lim, (Vertebrate Study Group, Nature Society Singapore). 2008. Wild Animals Of Singapore. Draco Publishing and Distribution Pte. Ltd. 180 pp.
  • Das, I. 2010. A Field Guide to the Reptiles of South-east Asia. New Holland Publishers (UK) Ltd. 376 pp.
  • Lim, K.P. & L. K. Lim. 1992. A Guide to the Amphibians & Reptiles of Singapore. Singapore Science Centre. 160 pp.

No comments: