Tatawa Besar is a large island in central Komodo that offers two great drift dives. The island creates an eddy, and the currents here almost always run south, irrespective of the tides. This makes Tatawa Besar a good choice when the currents are too strong elsewhere. The entry point for both dives is at the northern tip of the island, where the current splits. Descend to around 20-25 m where there are several large rocks harbouring numerous species of angelfish, batfish and sweetlips. Out in the blue schools of fusiliers feed, with giant trevally and blue fin trevally cruising past. It is worth spending some time exploring this area, as there are many treats to discover. After 10 minutes or so, you can choose whether to head east or west. Photographers may prefer the east coast in the morning and the west in the afternoon, to take advantage of the best light conditions. The east side is more commonly dived, and here the reef boasts some of the best coral cover in the park. The reef drops away steeply to about 25 m, but is best at 8-15 m. Large prostrate sponges, hydroids, and hard corals, combined with the colourful dendroneptha soft corals give way to fields of corpora and other hard corals. There are large rocks along the way providing havens for large sweetlips and groupers. It is difficult to dive this site without encountering one of the many resident hawksbill turtles, and keep an eye out for cuttlefish that are also often seen. At the end of the drift the reef drops away more steeply and the currents come to a complete stop. The water here is greener, flowing out from the nearby mangroves, and provides another dimension to the dive with entirely different coral species. The coral garden at 5 m is a great place to end the dive. The west coast of the reef can be dived along the reef slope, or up in the shallows. On the reef slope there is good coral cover, and it is best at the reef edge from 8-15 m. There are lots of angelfish of many different species, red-toothed triggerfish, lionfish and scorpionfish. Occasionally pelagics swim past in the blue water, and at the right time of the year manta rays. Alternatively you can drift through the shallows above 8 m where there are many large rocks, coral heads and porites. Between these outcrops schools of sweetlips, mangrove jacks, trevally and snapper cruise. The fish life here can be stunning and diverse. Under one rock a pair of stonefish are often seen—good luck finding them! About half way down the reef cover deteriorates, and it is better to move to the shoulder of the reef and follow the drift until the current stops. On a strong fall the current can push out from the reef a little, so be wary and avoid being pulled out into the choppy channel. Whether following the east or west shores, the drift on Tatawa Besar can become quite fast. But stay close to the reef and enjoy the ride, because towards the end the drift meets a counter current and everything slows down nicely.
The hawksbill sea turtle (Eretmochelys imbricata) is a critically endangered sea turtle belonging to the family Cheloniidae. It is the only extant species in the genus Eretmochelys. The species has a worldwide distribution, with Atlantic and Pacific subspecies. E. i. imbricata is the Atlantic subspecies, while E. i. bissa is found in the Indo-Pacific region. The hawksbill's appearance is similar to that of other marine turtles. It has a generally flattened body shape, a protective carapace, and flipper-like arms, adapted for swimming in the open ocean. E. imbricata is easily distinguished from other sea turtles by its sharp, curving beak with prominent tomium, and the saw-like appearance of its shell margins. Hawksbill shells slightly change colors, depending on water temperature. While this turtle lives part of its life in the open ocean, it spends more time in shallow lagoons and coral reefs. Human fishing practices threaten E. imbricata populations with extinction. The World Conservation Union classifies the hawksbill as critically endangered. Hawksbill shells were the primary source of tortoiseshell material used for decorative purposes. The Convention on International Trade in Endangered Species outlaws the capture and trade of hawksbill sea turtles and products derived from them.
Bleaching occurs when corals expel their symbiotic zooxanthellae - pigmented, algae-like protozoa that live within the coral's cells. High temperature, pollution or other stresses can cause the coral to expel its zooxanthellae, leading to a lighter or complete loss of color.