Did you know that coral actually is an animal? A coral is a polyp that has a hard skeleton formed by calcium carbonate. Many polyps together form a colony, and many different colonies of corals build our very important reefs. A polyp has a mouth and tentacles that often come out at night time, or when there is current and there is a lot of food in the water. They eat plankton and even small fishes that they catch with their tentacles. Most corals have a photosynthetic unicellular algae called Zooxanthellae, which transforms the sunlight into the energy that the corals need. This means that many corals need to live in shallow water and it has to be clean water so it can get sunlight. It is the Zooxanthellae what gives the corals the beautiful colours.
Nowadays everyone has heard about coral bleaching, but what is it exactly? It occurs when different factors in the water change, such as temperature, pH, etc. Corals starve to death because of over fishing, bacteria and many other factors. It takes as little as 1°C to start bleaching. Because of these different factors the coral gets stressed and can't keep the Zooxanthellae alive. This lost makes the coral white and that's why it is called bleaching. It means that the coral can't get the energy it needs anymore and will die.
Corals can grow via asexual reproduction or by spawning. Spawning happens once a year during the night and at full moon. Simultaneously the corals let go of their eggs and sperm packaged in a pink coloured bundle that has an elliptical shape. This process start six months before, when the polyp starts to form eggs and sperms. The corals rely on cues such as temperature, day length, tidal moves and lunar cycles: the temperature needs to be 27°C or more, full moon and minimum tidal moves. Imagine all corals in the sea spawning at the same time, there will be millions of these pink bundle packages!! Not only it is an amazing thing to see it also attracts fishes, which makes the diving even more interesting.
The coral spawning happens all around the world in different months, according to their temperatures and seasons. So if you would like to see this "sex on the reef" you can for visit Micronesia in July, Australia in November, Cayman Islands in September. If you go to Hawaii between April to September you might be lucky to see coral spawning in daylight which is the only place in the world that happens.
There is a globe epicenter of marine diversity called the coral triangle and is one of top priorities for marine conservation work. This Amazon of the seas covers 5.7 million square kilometers. You will find the triangle in Indonesia, Malaysia, Papua New Guinea, Phillippines, Solomon islands and Timor - Leste. This space of water contains the highest diversity of corals and most of the marine life in the world. Here you will find 76 % of the world coral species. The best places with beautiful healthy coral reefs don't just give you colorful diving, it also attracts other marine life. So if you want to dive in beautiful coral gardens full with marine life the coral triangle is the place to go.
Fiji is acknowledged as the "soft coral capital of the world" and it is not without a reason. But it's not just soft coral, as they also have hard coral reefs. Taveuni is probably the best place to go, it is close to world class Rainbow reef, Somosomo and Vanua Levu. Thanks to nutrient rich sea this place is a coral wonderland with a ecosystem of incredible diversity.
Do you want to see 70 % of all coral species in one spot? Go to Walindi in Papua New Guinea is situated in Kimbe Bay on the north coast of West New Britian Province. Water temperature is between 25-27° C and best season is from May to November. The reef is undamaged, well protected and monitored by Nature and Marine Research Center. Their policy is "look but do not touch", which should be every diver's policy.
And if you are in Papua New Guinea another good place is Raja Ampat (Indonesia), which is located in the West Papua Province. This is a paradise for hard corals lovers, where about 600 different species can be found, which is more than half of all record species in the world.
Tubbataha reef located in the Sulu Sea in Philippines is a world heritage site. This reef has a unique and fragile underwater ecosystem, and is protected and monitored with conservation work. The best time to go is between March to June.
Another dive spot that is listed as world heritage is the Marine Park in Bunaken, located in Manado in north Sulawesi (Indonesia). Established as Marine Park 1991, the oceanic current makes this marine park a biodiversity treasure. Its rich coral ecosystem is dominated with fringing reefs and barrier reefs, with many hard corals but also soft corals. Best diving season is between April to November and the water temperature is 27-29°C.
Micronesia is another diver's paradise. Some of the most famous dive sites are found in Palau, which consists of over 200 islands and covers a distance of 125 miles. This is a home to more than 700 coral species. Probably this huge biodiversity is due to the three different oceans meeting in Palau waters. Turk lagoon, also in Micronesia, is a wreck paradise but in time they have transformed into colorful soft coral gardens.
There are other really good places for coral diving outside the coral triangle. One of them is of course the world largest coral reef, the Great Barrier Reef outside Queensland's coast, and it's 1800 miles long. This reef is listed as one of the seven natural wonders in the world and also listed as a world heritage site with good reasons. In the past recent years it has been suffering with to many irresponsible divers, but if you hop on a liveaboard and go far out, you will find amazing coral gardens. Between June to October is the best weather conditions and the clearest water.
Not many people know that Belize is home to the second largest barrier reef, which is also a good spot to see huge coral diversity. The Mesoamerican reef in the Caribbean Sea is one of the world most colorful hosting the most gigantic corals in the world, and is well protected against tidal movements and strong currents. Here every year new species are discovered, and is the rich variety of reef and lagoons what gives the huge coral diversity. The Lighthouse reef in Belize is one of the best examples of this diversity. But Belize is not the only place in Caribbean that has nice coral diving. You will find gigantic colorful corals almost anywhere you go in Caribbean, one of the best places is the Green Out House Wall in Roatan, Honduras, the French Cay in Turks & Caicos island and Sak Pier in Bonnaire just to mention some dive spots.
But let's not forget about Africa, probably most famous for the big marine life such as sharks, manta rays, whale sharks and dolphins, but the Indo-pacific oceans also offers nice coral gardens. The best spots for coral diving is Zanzibar in Tanzania, Sodwana Bay in South Africa, and Tofo in Inhambane province in Mozambique.
A more or less secret place is Aldabra, the second largest coral atoll, and it's located in Seychelles. It's an extremely isolated place, which only few people visit. The only few persons living here are crew members of conservation organizations. The lack of tourist makes this one of the most untouched reefs in the world. This is a coral and marine life paradise and this is how a coral reef should look like all over the world. Best time to visit is Mach - April and September - October.
Remember, if we didn't have the corals we wouldn't have any reef, and without the reefs we wouldn't have any fishes. So go, dive and enjoy all the beautiful corals that are out there. Go close to them, not too close though, and look what is hidden in the corals. It's a good place to find crabs, squid eggs and other small creatures.
(By Susanne Stigsson)