The Indo-Pacific region is very rich in marine life. This vast tropical maritime region stretches halfway around the Earth, from the east coast of Africa to the remotest islands of Polynesia. Not only is this the largest marine biozone, but also the richest one. The center of its biodiversity, made up by East Malaysia, the Philippines, eastern Indonesia, East Timor and Papua New Guinea is known as the Coral Triangle.
Eastern Indonesia has a richer marine life than the West of the country. For example, there are 15 species of rabbitfish in the East, but only 12 in the West. The West is made up by Sumatra, Java and Kalimantan, the East is Sulawesi, Nusa Tenggara, Maluku and Papua. Whereas the Indo-Malay region is the center of marine biodiversity of the Indo-Pacific, East Indonesia is the center of Indo-Malay region's biodiversity.
One reason for this richness is the very position of Indonesia. Indonesia lies at the border of two continents, Asia and Australia, and two oceans, the Indian Ocean and the Pacific. The faunas of both oceans and continents meet in Indonesia. There are also other reasons. While many geological regions of the Earth have experienced movements away from or towards the tropics, much of Indonesia has always stayed close to the Equator. While many tropical species died out due to those continental shifts, they survived in Indonesia. As an example, the Thetys Sea was an ancient ocean that stretched from Indonesia to the Atlantic, but disappeared due to continental shifts ca 15 million years ago. Recent research however found that several species of coral found around the Togean Islands of Central Sulawesi are actually relics of the ancient Thetys Sea fauna.
As we had mentioned earlier, another factor is that Indonesia is located at the border of two oceans, both of which have added their own marine fauna to the archipelago. This made Indonesia richer in marine life than the neighbors.
There is a long geological history to the meeting of these two oceans. In the past, during the Ice Age, much of the Earth water was frozen solid towards the polar regions, and the seas elsewhere became shallower. At the peak of the Ice Age, the seas were on average 120 meters shallower than today. Much of Indonesia that is today sea then became dry land. The seas around Sumatra and Java were no deeper than 50 meters. The islands of Sumatra, Java and Borneo joint by this shallow sea was known as the Sunda Shelf. Over in the East, a land bridge joined southern Papua to Australia known as Sahul. On the other hand, the Flores and Banda Seas remained very deep. This is the reason why Australia and Papua share a similar marsupial fauna, while Asian species like the tiger reached Java and Bali but not Lombok or Sulawesi.
Indonesia is the least known of the world's best dive locations. The introduction of scuba gear and the beginning of of dive operations here are barely some decades ago, and the new locations are still being explored and opened, albeit slowly. It will be many years before diving in Indonesia reaches it's full potential, which has both great advantages and serious drawbacks. Experienced divers will be excited by the possibility of diving clear, rich waters without being surrounded by hordes of human beings. It is still very possible to dive areas where no one has yet gone underwater.
Exotic Bali lies east of Java. Most of its people follow the Hindu religion, except in the westernmost part closest to Java, where the mixing with many migrants from that island has lead to a mixed culture. Religion is extremely important in Bali. When you are in Bali, you can't fail to notice that most houses have their own family temples and plant frangipani flowers nearby. On special days, the Balinese carry out unique rituals carrying impressive, high offerings made from flowers, fruit and even the odd little roast piglet. Smaller offerings of flowers are made daily everywhere — you will find them on your doorstep in the mornings!
The island of Sulawesi possesses rich culture. It is also known for its many great beaches. And among divers, the islands of Bunaken and Wakatobi are world famous. These islands also often play host to both domestic and international events such as Sail Bunaken. The waters are crystal clear and the strategic location ensures that strong currents constantly bring plankton here from the seas to the South and North. Rich fishlife is the result. In archipelagoes like Wakatobi, you must visit various islands, like Wangiwangi, Kaledupa, Tomea and Binongko that gave it its name, to fully appreciate the diving potential. The Togean Islands are another place with extraordinary underwater visibility.
Long ago, Maluku was best known for its spices. Traders from as far as China, the Middle East and even Europe came here for their coveted, rare spices. Today, Maluku is better known for its underwater treasures. Many of the local people now live from fishing and there is a good reason for that. Maluku's waters are teeming with big fish such as tuna, jackfish, barracuda and also huge quantities of sardines and squid. Anthias, wrasse, angelfish, butterfly fish, snappers, moorish idols and all other sorts of coral reef fish are found throughout the Maluku islands.
Papua is the latest dream destination of divers. It is one of the Indonesian islands that form part of the Coral Triangle, the center of global marine biodiversity. As with Maluku and Nusa Tenggara, the underwater riches of Papua have only become known to divers in the past decades. But now the secret is out and the beauty of Papua’s dive spots is world famous. Even just 5 years ago many areas of Papua were very difficult to reach due to limited facilities and lack of information.
Nusa Tenggara is made up from many islands east of Bali, stretching along a west to east axis between Bali and East Timor. This is Indonesia's driest region with a relatively low annual rainfall, creating an arid landscape covered in savana vegetation similar to that of neighboring northern Australia. This is in sharp contrast to the extremely rich marine life of these islands. The 1300 species of fish found here are the highest total in Indonesia along with that of Papua. New species of coral and fish are still discovered in this region, such as Paracheilnus rennyae discovered in the waters of Komodo National Park.