Kakaban Island. Photo by: Ale
Derawan Islands has three districts namely, Derawan Island, Maratua, and the Biduk biduk, Berau. There are at least four famous islands in this Archipelago, which is Pulau Maratua, Derawan, Sangalaki, and Kakaban.
The Islands in Derawan archipelago is about 31 island, which is some of them are bar (gusung) and atoll. Atoll is a coral island surrounding by a lagoon partially or completely. The used of the lands by local inhabitant in these island is only limited for the home living. In addition, the land of the island in the Derawan archipelago still in the form of mangrove forests, thickets, limestone forest in Maratua and coconut vegetation.
The terrains at Derawan Islands are varied-from walls and fringing reef to caverns. Big green turtles (chelonia mydas), hawksbill turtles, dolphins, whales, mermaids, whitetip leopard and nurse sharks, schooling barracudas, napoleon wrasses, cuttle fish, spanish mackerel, jacks and batfishes, and ornamental reef fishes hang out in record densities and diversity.
The Island of Kakaban is an excepfora marine environment. An uplifting in the area during Holocene transgression, about 19000 BC has left 5 sq kilometers of seawater trapped within a 50 meter (165 ft) ridge, turning the area into a landlocke marine lake. The only other know lake of such nature found in Palau, Micronesia, is a desert compared to kakaban. Another island in the chain, Semama, is an important bird sanctuary, and Kakaban Island contains the world’s largest and most diverse jellyfish lake, with four unique species of stingless jellyfish. Kakaban is being considered for nomination as a UNESCO World Heritage Site.
The types of coral reefs in Derawan Islands consist of reef edge, barrier reefs and atolls. These atolls have been formed into an island and being a lake of salty water and it has 460 to 470 numbers of species indicates that this is a wealth biodiversity, giving it the world’s second highest level of hard coral diversity after the Raja Ampat Islands in eastern Indonesia.