Tentative identifications:

  1. Barramundi (Lates calcarifer)
  2. Goatee Croaker (Dendrophysa russelli)
  3. Bearded Worm Goby (Taenioides cirratus)
  4. Barramundi
  5. Green Chromide (Etroplus suratensis), Toadfish (F. Batrachoididae, Wrasse (F. Labridae)
  6. Decorated Ponyfish (Nuchequula gerreoides)
  7. Green Chromide, Toadfish, Striped Eeltail Catfish (Plotosus lineatus)

Reporting from Seletar Dam facing Johor side. Unusually strong pungent smell from the sea got my curiosity as I was riding past this stretch.

Along the shores was a zone of 2 metres with dead horseshoe crabs (F. Limulidae), Mangrove Whipray (Himantura walga), Flower Crab (Portunus pelagicus), Grouper (Epinephelus sp.), Sand Whiting (Sillago sp.), Green Chromide (Etroplus suratensis), Spotted Scat (Scatophagus argus), Barramundi (Lates calcarifer), Toadfish (F. Batrachoididae), shrimps and huge colonies of marine bristleworms (Polychaeta).

Source: Benjamin Li Facebook

(This is Part 3 of a 3-part photo set)

Photograph by Ria Tan

Lagoon Shrimp-goby (Cryptocentrus cyanotaenia) at eastern Johor Straits

Location, date and time: Singapore, eastern Johor Strait at Pulau Sekudu, off the south-eastern corner of Pulau Ubin; 9 May 2004; 0723 hrs.

Observation: An individual of about 12 cm total length was found dead on its side on the sand substrate, in ankle-deep water during morning low tide (see accompanying picture). It was in very fresh condition, and seemed to have expired no more than an hour before. The cause of its death is unknown.

Remarks: The Lagoon Shrimp-goby is easily distinguished from other Cryptocentrus species in Singapore with narrow oblique blue lines on its head and at least 10 narrow blue bands on its body (Larson & Lim, 2005: 84). In Singapore waters, this species is also known from Punggol in the Johor Straits, and Pulau Retan Laut (since reclaimed) and Pulau Hantu in the Singapore Straits (Larson et al., 2008: 147).

References:

  • Larson, H. K. & K. K. P. Lim, 2005. A Guide to Gobies of Singapore. Singapore Science Centre. 164 pp.
  • Larson, H. K., Z. Jaafar & K. K. P. Lim, 2008. An annotated checklist of the gobioid fishes of Singapore. The Raffles Bulletin of Zoology. 56 (1): 135-155.

Source: Singapore Biodiversity Records 2014: 334

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.