Friday, May 1, 2009

Snailing Sipadan and Mabul

Well known as a world class diving destination, Sipadan Island and it's neighbour, Mabul Island also hold some interesting topside flora and fauna, including a hoard of new-to-science snails.
Mabul Island
- A heavily developed island north of Sipadan. Most of the greenery on the island are coconut palms planted by native Bajau and Suluk people. The only remaining original forest,less than 2 acres, lies in the East side of the island. This narrow strip of forest has a wide path cutting through it the centre and is surrounded by worker's quarters and storage rooms of a nearby resort. Apparently, it lies it the property of the resort itself. I found 3 unidentified molluscs here:

Obba cf. marginata- Found dead in a cleared area near the forest. I tried to find live ones in the forest but couldn't. It resembles Obba marginata from Mindanao,Southern Philippines.

Videna sp.- Because there is no proper study to sort out the various species of this genus, the shell's identification couldn't be ascertained. But recent studies shows that this genus does exists in the Semporna archipelago.

Amphidromus sp.- An abundance of dead specimens were discovered around the coconut plantations and resorts. The broken shell on the left shows the original colouration. No live snails found.

Sipadan Island- Relatively untouched by resort development due to strict management rules and it's status as a marine sanctuary. Other than several abandoned chalets in the North, this island is densely covered with coastal forest vegetation. There are lots of hermit crabs, skinks and clouded monitor lizards (Varanus bengalensis nebulosus). Lucky visitors might be able to see the endangered nicobar pigeon (Caloenas nicobarica)as well as the rare ground dwelling megapode bird(Megapodius cummingii).The biodiversity here is intact. It also supports a healthy population of molluscs:

Pythia scarabaeus- Abundant amongst trees trunks, stems, fallen leaves etc. A widespread species throughout Southeast Asia's coasts.

Amphidromus sp.- Found living on pandanus sp. trees' aerial roots. It has a zigzag patterned periotracum. Different from Mabul Island's amphidromus as it has less whorls than Mabul's. Possible endemic species.

Both islands illustrates the diversity of the region as well as it's problems vividly. Mabul has lost most of it's diversity due to over development whereas Sipadan shows the success of the sanctuary's strict laws of conservation. They also revealed the undiscovered molluscan fauna of the Semporna archipelago. The new discoveries beckons......