Located on the heart of Indonesia and it is a one big island size 544,150 km2. There are small islands around the main island with stunning Marine Life:
Derawan islands is a part of Coral Triangle, which contains one of the richest marine biodiversity on earth. Located in a biodiversity hotspot, the Derawan Islands feature 872 species of reef fishes, 507 species of coral, and invertebrates, including protected species (5 giants clam species, 2 sea turtles, coconut crab, etc.). Some of the islands harbor the heavily exploited turtle eggs and yet the largest green turtle nesting site in Indonesia.
Kakaban island is part of the Derawan Islands, and it has an area of 774.2 hectares and is quite steep. Its limestone cliffs are covered with dense jungle right down to the water’s edge. The wall drops to 180 meters, and currents can be strong with up-welling, down-current and reversing directions.
Derawan and Sangalaki
Derawan is home to numerous critters plus turtles (green turtles and hawksbills) that come to the shore at night during high tide to lay their eggs.
Kakaban features wall diving, with the walls patrolled by schooling barracuda, bluefin tunas, jacks, leopard sharks, gray reef sharks, and sometimes hammerheads. The world’s largest jellyfish lake is here also. Halimeda green algae covers the bottom of the lake, and mangrove roots live side by side with tunicates, sponges, tube worms, crustaceans, anemones, sea cucumber, sea snakes and gobies. Still unidentified species abound.
Sangalaki is home to squadrons of giant manta rays. They emerge from all directions, undisturbed by your presence. Most are at least 3.5m (12 ft) wide. These have the typical white underside but there are also a few black mantas with 6m (20 ft) wingspans, referred to fondly as Darth Vader fish.
Maratua island boasts a massive lagoon. The island only rims apart of the lagoon, with the rest fringed by a reef and wall covered with hard and soft coral.