Bunaken National Park is located in North Sulawesi, Indonesia. With over 8,000 hectares of coral reef, an estimated 2,000 species of fish and at least 58 different genera and sub genera of corals in the park its no surprise this region has been an attraction for divers for many years. The reef slopes range in depth from 50 meters to over 200 meters, the deepest of which are found between the islands of Mantehage and Manado Tua, at over 1,300 meters. This is possible only because of the lack of a continental shelf, part of the reason Bunaken Island plays host to such a wealth of marine life. Nutrient rich waters are fed through oceanic channels. Upwelling brings this food source closer to the surface where many species feed. Its these ingredients that attract those wishing to dive Sulawesi.
Many hard and soft corals compete on the reefs that surround the park. Colonies of animals individually referred to as ‘polyps’ are joined together by a thin layer of common tissue. They generally survive at depths between the surface of the water and 30m. All corals contain zooxanthellae, a species of algae which converts sunlight into food through photosynthesis; the excess nutrients not used by the algae are consumed by the coral, this is known as a symbiotic relationship.
Reef dwelling fishes live around the coral reefs and lagoons of the park. They rely on the reef as a food source and for shelter. Most reef fishes rest during the night, whilst being active during the day. These include the butterfly fish, angel fish and gobies amongst many other families. Pelagics however are open water fish, travel long distances and are generally faster swimmers. These include trevally, tuna and sharks.
Marine reptiles also inhabit the park. Estuarine crocodiles have been sighted in the mangrove areas, although sightings are very rare. Sea snakes, despite spending considerable amounts of time beneath the surface are air breathers making them reptiles and are often seen by divers, particularly in sea grass beds and mangrove areas.
Of the eight species of turtle found worldwide at least five live in Indonesia, three of which make regular sightings. All in all Bunaken Marine Park supports an incredible wealth of marine life. For those wishing to experience diving in Indonesia, Bunaken is a must see destination.