the delicate ecosystme

Tropical warm seas contain the great reefs of coral growing in shallow water. The so-called coral islands found in the south seas, of which the Maldives is a prime example, are made from the limestone skeletons of millions of these invertebrate marine organisms which belong to the class "Anthozoa" (anthos flower, zoion animal) and which live in colonies, sharing the work of feeding, cleaning, and defense.

Each unit of the coral is known as a "polyp" which secretes the stony skeleton which is almost pure "Calcium Carbonate". Corals along with sea anemones and jellyfish are collectively called coelenterates, Greek for cavity, which aptly describes their basic body structure. All concentrates are simply a hollow sac with a mouth at one end surrounded by tentacles. These tentacles armed with stinging cells help them to paralyze small swimming animals which are then pushed into its mouth. The polyps of some of the corals do not have long tentacles, thereby passing the food to its mouth by the cilia coating the tentacles. Corals feed by photosynthesis of marine algae living on coral tissue. They also follow a carnivorous diet, plankton being the favorite.

There are several kinds of corals of which the stony coral (Order Madreporaria or Scleractinia), numbering around a thousand species, is the most widely distributed. Livign either solitarily or in colonies, stony corals occur in all tropical oceans, growing best upto 30 metres. These corals are also sometimes seen at an incredible depth of 20,000 feet. Stony corals make up vast coral reefs and Atolls, some of them as old as 70 million years. When one polyp dies another takes its place and continues to grow untill the reef is created.

However since then by nature are slow in their growth (averaging about 5 to 28 mm a year), a damaged or destroyed reef requires a long time to rebuild. The most common and most popular types of stony corals include the mushroom, the brain, the staghorn, and the star corals, all named so for their distinctive shapes. The 1,200-odd species of horny corals (Gorgonacea) thrive in shallow tropical waters. Their branches, sometimes ribbon-like, can grow to lengths of occassionally upto 10 feet. The rose coral belonging to this class is used in making interesting pieces of jeqellery. The one living species of blue coral (Coenothecalia) occurs on the reefs of stony corals. Colonial oceans where they form large lumps, some of them spanning two metres in diametre.

Other kinds of corals include the black and thorny ccorals (Antipatharia), numbering a hundred species; and soft corals, a widely distributed group. Soft corals are not true corals. One important distinguishing factor is their tentacles which, instead a being simple as in true corals, are fringed and each polyp has 8 tentacles instead of the usual 6 or a multiple of 6. A close relative of soft corals is the beautiful organ-pipe coral, which when it expands resembles a delicate flower. The organ-pipe consists of a mass of vertical tubes, joined at intervals throughout their length by thin horizontal plates. The purplish skeleton contains a pale lilac-coloured polyp.

Though almost all corals are sedentary, ie; animals permanently fixed to the substratum, there is a species of wlaking coral. Though dubbed so, it actually does not move on its own, but represents a fine example of symbiosis. The Heteropsammia Michelinii has a marine worm living in its limy skeleton and as this worm moves around, foraging for food, it drags the small one-inch-long coral with it.

The reef islands of the Maldives is the result of a process of coral formation known as "accretion". Rubbles of reef rock broken off from the reef by heavy cyclonic storms and waves create reef-top shoals. Due to the normal action of waves and ocean currents other materials begin to gradually accumulate. Beaches develop around these shallows with the wind heaping up the lighter materials into dunes. The material being almost entirely made of Calcium Carbonate readily dissolves in rainwater and the dissolved lime is then redeposited around the loose materials, cementing it together. Soon such newly-formed islands are inhabited and colonised by plants and animals.

Corals exemplify some of the richest known ecological communities supporting countless other living organisms, intertwined in the complex web of food and resource competition. Seaweeds grow on the skeletons of dead coral together with sponges and other animals. Molluscs graze on algae while predators cush as Reef Sharks, Groupers, Rock Cod, Lionfish, Scorpionfish, Stonefish, and Eels lurk amongst the coral jungles which provides them with a perfect hunting ground. At times corals themselves end up in the beak-like jaws of parrotfish or other predators like butterfly fish, commonly found denizens of this spectacular microcosm.

Reefs prevent soil erosion. And with their brilliant hues and sculpted shapes corals and beauty, enticing people to dive underwater to appreciate some of nature's most magnificient of creations. Corals constitute a very delicate ecosystem which requires our tender care and nurturing.

Visitors are advised not to pickup corals from the sea or attempt to export them.

For centuries man's fear of the wild has been attributed to the lack of knowledge and little understanding of the beast. The Shark is no exception to this, and even in this modern age, people continue to believe that all sharks are dangerous and are man-eaters. Like the lion in the jungle, the shark is seen as the lord of the oceans.

It was Herodotus, the father of History, who recorded in his histories the presence of this creature some 2,500 years ago. His writings gave a mythological touch to the shark. Nearly a century after him, his fellow countryman, Aristotle, the reputed Greek Philosopher and scientist, wrote his observations on the behavior of sharks in "Historia Animalium". This information remained as the most thorough study of the subject untill the 18th Century.

Long before man appeared on earth, sharks roamed the ocean. Fossil studies indicate sharks to have appeared in the Palaeozoic era at least 400 million years ago, and their comparatively low degree of evolutionary adaptation proves their age-old superiority over their environment and competitors. Today there are 344 known species of shark. Even there are many tragic stories, recent research reveals that most sharks do not attack humans.

Among the sharks that inhabit the Maldivian waters are the Grey Reef Shark, Nurse Shark, Silver-tip Shark, White-tip Shark and the Black-tip Shark. The "Grey Reef shark" belong to the category of active predators and therefore they have elaborate ears and a lateralis system which can alert and locate the source of sound quickly and accurately. They also have a very strong sense of smell.

They are known to have attacked humans in other seas but not in the Maldivian waters. Maldivian divers believe that this is because these waters around the archipelago are abundant in food. They also agree that sharks have far more reason to fear humans than humans have to fear sharks.

Eels live in holes and crevices in the corals. They have a serpentine motion. Eels are strong animals with sharp teeth. They feed on fish and crustaceans, mostly at night. Unless provoked they do not attack divers. Moray eels are common in the Maldivian waters. They are curious of human beings.

Turtles differ from all the other species discussed in this web site (WWW.hellomaldives.com). They are reptiles. Sea reptiles are the most threatened of all the animal groups. The hawksbill turtle illustrated in this section has been hunted by man to make jewellery and ornaments and is in danger of extinction. Females deposit a clutch of eggs on the sandy coasts of the Maldives. when hatched, the young turtles swim away, but only a few will survive to reach adulthood. The Maldivian waters are one of the richest in hawksbill turtles.

The sea gives life to many myths and legends but few stories can match those that are born from the valuable nuggets of ambergris that can be found floating in the sea or washed on the beaches of islands. Ambergris is a waxy substance produced in the intestines of sperm whales. Sperm whales eat deep-sea squid and it is believed the undigested beaks of the squid cause irritation to the internal organs of the whale. In response, the whale produces a secretion, which coats these beaks. It is this highly prized secretion, which is passed out at either end that is of such value. When heated it gives out a particularly agreeable perfume. It is used for medicinal purposes and perfumes.

The Chinese of the 10th and 11th century called ambergris 'Dragon Spittle' and they collected most of it from the Liu Mountains (Maldives). Sheng-tseng wrote: "There are a great many coiled up dragons among the rocks of these islets. In spring they vomit spittle, which flocks of birds collect and swarms of fish suck up. The yellow kind is like fish glue, the black like the dung of bats, the white resembles pai-yao-chien."

The Arabs thought differently. Suleiman, wrote in the ninth century: "The sea throws up on the shore of these islands big lumps of amber: some of these pieces have the form of a plant, or nearly so. Amber grows at the bottom of the sea like the plants; when the sea is much disturbed, it throws up the amber in pieces like pumpkins or truffles."

The Portuguese soldier Barbosa, in the east between 1501 and 1517 was intrigued by it and wrote: "I have oft times asked these Moors what thing this ambergris was, and hence it sprang. Among themselves they hold it to be the dung of birds, and they say that in this archipelago among the uninhabited islands there are certain great fowls which alight on the cliffs and rocks of the sea, and there drop this ambergris, where it is tanned and softened by the wind, the sun, and the rain, and pieces both great and small are torn by the storms and tempests and fall into the sea until they are found or washed up on the strands or swallowed by whales."

An anonymous Portuguese writer writing prior to 1505, found out the true source of ambergris. He wrote: "On the shores of the Dyve islands, dead whales are to be found. They are often thrown ashore by the waves and the inhabitants cut them and make oil of their meat. Some of these whales have pieces of ambra like pinecones, big and small ones, 20 to 40 or even 100 and sometimes up to 200 pieces joined in a big sticky bunch. This ambra they must deliver to the sultan, if they do not they are sentenced to death. Nobody tries to steal it as it is under penalty of death."

The value of ambergris is such that when one becomes suddenly rich it is commonly said that he has found ambergris, as though it were treasure. It was only the rich or royal, however, that kept it. In 1599, the English pilot, John Davies reported being greeted near Male by a "gentleman and his wife", and mentions that in the woman's casket were jewels and ambergris. The man, who was dressed "in the Turkish manner" and had rings with rich stones is believed to have been Sultan lbrahim Ill.

The freedom of the people has been bought with ambergris. In 1754 a piece weighing 152.8 kgs was presented to the French in return for their services in defeating a fleet of Malaabar vessels that had been plundering the islands.

Ambergris found today is worth around US$ 2.50/gm and if exported is taxed 100% by the government. In March of 1995 a piece weighing 187 kgs, the second largest piece found this century, was found by fishermen off the island of Kelaa, in North Thiladhunmathee Atoll. The largest piece of 214 kgs was found in the early 1980s. Needless to say, finding a piece of ambergris is like unearthing a nugget of gold. However, the fortunate discoverer must grab hold of it first try once touched it sinks to the bottom and takes days to surface!

Man has caught and eaten fish since the stone age. For over a millenium the variety and the beauty of fish has been admired by poets, philosophers, writers, and maturalists. But it was only in the last century that serious studies began on fish speciation and classification. Fish are found in an extraordinary range of habitats, from mountain streams to hot springs and at depths below 7,000 metres. There are some 20,000 species of fish and the Maldivian reefs and seas boast over 2,000 species.

Fish show amazing diversity and are unique in their variety of breeding and development patterns. They possess specialized sensory organs, nostrils, eyes, nerve endings or other senses to gather information. fish can also monitor temperature,, light, colour, dilution, gases, pressure or depth, water currents, vibrations, etc. External fertilization is common where the male fertilizes the eggs laid by the female and left to develop. The fish also has the ability to live with an array of other species forming symbiotic or other relationships.

No fish is immune from attack. However, through the ages fish have devised their own systems of defence. One is schooling, a behavior where the fish gather together when a predator appears. This confuses the predator as to which fish is to be singled out and attacked. When pursued, a fish can suddenly go into sedentary existence on the bottom of the sea. But the fish can then become a potential prey of the bottom dwelling predators. Camouflage, where a fish can blend with the background or mimicry where the fish can mimic the appearance of another animal is another way of surviving. Some fishes can erect their modified barbed spines in case of danger or the sharp spines of the dorsal fin can appear as a mode of defence. The waters around the Maldives are abundant in rare species of biological and commercial value.

Rays are formidable creatures if the ocean, Manta Rays, Sting Rays and Eagle Rays are the commonest rays in the Maldivian waters. The Manta Ray, shown to the right is the largest ray in the World. Manta rays are also known as "horned rays" because of the two small fins on their head. They take in small fish and plankton while swimming and drain out the water. Manta rays are not aggressive.