Three species of mudskippers found in Singapore.

The eleven or so species of mudskippers found in Singapore are commonly seen in mangroves and mudflats, as well as in various other coastal habitats. Some smaller species have colonised rocky seawalls and breakwaters along our beaches and coastal lagoons, while others are found in the lower reaches of concrete drains and canals.

These highly specialised fishes flourish in environments where few other conventional fishes can, thanks to various adaptations that enable them to breathe out of water. Many species have special pouches in their gill chambers, enabling them to trap oxygenated water and air bubbles. In this manner, the gills are still able to function while the mudskipper is out of the water. So just like how a scuba diver brings an air tank down into the water, these are fishes that bring water tanks up onto land!

Some mudskippers are also able to gulp air and directly absorb atmospheric oxygen through the lining of the back of the mouth and throat, or even through moist skin.

Not all mudskippers are the same; some are more aquatic and prefer shallow mangrove creeks and pools or mudflats, leaving the water only to escape adverse environmental conditions and search for new bodies of water. Others are more amphibious, preferring the water’s edge and spending most of their time on land. Mudskipper species also differ in their diets, with some feeding mostly on algae, and others being predators of invertebrates such as worms and crustaceans.

Yellow-spotted Mudskipper (Periophthalmus walailakae) (Upper Left): This medium-sized species (up to 12 cm) found in mangrove forests is a carnivore, lunging at small crustaceans and insects.

Blue-spotted Mudskipper (Boleophthalmus boddarti) (Lower Left): This medium-sized (up to 13 cm) species can be abundant along river banks and creeks, and on mudflats on the fringes of mangrove forests. A herbivore, it feeds by wiping its face along the surface of the mud, scraping up benthic algae growing on the mud.

Giant Mudskipper (Periophthalmodon schlosseri) (Right): The largest of the mudskippers (up to 30 cm), this species inhabits mudflats, clearings in mangrove forests and edges, as well as the banks of tidal creeks and other open areas. It is often seen in or near the circular pool that it builds at the entrance of its burrow, which has a low rim of mud to trap some water even at low tide. Its size enables this predator to feed on small crabs and even other mudskippers.

These were some of the many specimens featured at the recently concluded Festival of Biodiversity 2014, which was held at VivoCity last weekend.