Is it its permanent smile, its large head, its rarity…..?
The dugong or sea cow has fascinated sea lovers for centuries. The dugong, or "dugong dugong" (New Latin Dugong, genus name, possibly from Malay dugong), is part of the sirenians specie. "Sirène" means mermaid in French. The better known manatee, fresh water cousin to the dugong and the now extinct "Steller Rhytine" are also part of this specie. They are believed to be the origins of the mermaid legend. They are an endangered specie. The dugong is a mammal and grass eater, therefore its name of sea cow. But in fact the dugong is more closely related to the elephant. According to biologists, dugongs and elephants must have had common ancestors. Marine mammals include the cetaceans (whales and dolphins), the pinnipeds (seals and walruses) and the sirenians. All marine mammals evolved from land mammals that returned to the sea, changing shape accordingly. Seals and toothed whales probably started out as dog-like carnivores. Baleen whales were probably something like hippos, and serenians appear to be related to elephants. Dugongs are found in Australia in large groups and in small groups in the warm waters of the world (Indian Ocean, Red Sea, Pacific Islands), between latitudes 30° North and 30° South. Manatees are found in the fresh waters of some tropical and subtropical coasts and rivers on both sides of the Atlantic : Florida, Caribbean, Amazon, and West African coast.
Since it is now a shy animal and lives mainly in murky shallow waters, where it feeds on sea grass beds, the dugong has very rarely been filmed or photographed. It had never been filmed playing with humans, until an intrepid team from France (Loyer, Michaud, Fournier) changed that. The photographs in this article, by Raphael Christian Fournier, were taken in Tanna, island of Vanuatu, located 5,750 km (3572 miles) southwest of Honolulu in the South Pacific Ocean about three-quarters of the way between Hawaii and Australia.
The story of the Tanna dugong : a few years ago (no one can tell exactly how many, since the people of Tanna, the Yanbinans, do not keep track of time), a dugong and its calf entered the bay. The villagers speared the mother and kept the baby as a pet, bringing it for short periods of time inside their huts ! The legend has it that the speared dugong reappeared as a dugong shaped rock in the center of the village. The baby dugong grew very big and now lives in the bay. It is very tamed and responds to the thrashing of the water by the kids. It comes to the very same rock every day, except when it is busy playing with turtles at the other end of the bay. Yes it is quite a sight to see it throw turtles up in the air ! This is just unexplained playful behavior from a herbivorous animal. The turtles end up unharmed, just shaken by the dive. This dugong must have now reached sexual maturity and has never seen any other dugong since its mother was killed. It obviously needs company, playmates or mates…. The Yanbinans love their pet. They call it "Ponta". They were relieved to hear that the estimated life span of the sea cow is seventy years. Why did they kill the mother, then ? The exploit and the food, obviously. They are pleased to hear also that a tamed dugong is a rarity. A project for a large resort in Port Resolution by "Hotel Corail" is under way. Will "Ponta" survive ?
Dr. Paul Anderson of the University of Calgary, Canada, Helen March and The Dugong Research Group from James Cook University in Townsville, Australia, Pascale Joannot, marine biologist and director of the Nouméa aquarium and Claire Garrigue, scientist for "ORSTOM" and responsible for the Nouméa program "lagoon" are some of the world’s leading dugong experts. They seem to be the only ones concerned with the alarming rate of disappearance of this friendly specie.
The dugong is only "partially protected". People kill it for food. Its red meat is apparently excellent. So the animals are now scarce and now very cautious. The dugong has very good senses of smell and hearing, making it very difficult to approach. It did not used to be that way : see year 1707 report further down.
The dugong is large, up to 3.3 meter (10 foot) long and up to 400 kg (800 pounds). A grass eater of this size is believed to spend fifty per cent of its life eating. Grass produces less calories than meat. This sea mammal grazes on beds of phanerogames (Zostera marina and Zostera Nana) and absorbs every day the equivalent of one tenth of its weight.
The sea cow comes to the surface every two to five minutes to breathe. Only the very tip of its nose comes out of the water, and for a very brief time, a couple of seconds only. The two nostrils open and close like valves. When the sea is rough, this clever mammal surfaces perpendicular to the surface, between waves, so as not to inhale water. When it is calm, it surfaces more parallel to the surface, for reasons of his own, not yet understood.
The dugong has a fat plump body, a large head with a blunt snout, a short but flexible neck, tiny eyes, no external ears, clawless foreflippers, and a fluked tail (a deeply notched tail fin) contrariwise to the manatee, whose tail is one part and rounded. Like all mammals, its tail is in the horizontal plane and the animal moves in the vertical plane. This sea mammal has no legs. It has two flipperlike forelimbs, or pectoral fins, without nails, which it uses to move, to fight and to grasp its babies. It swims slowly, but is capable of fast and efficient accelerations when frightened.
Its skin is thick, from grey to bronze, with white spots on older animals. It has little hair, except around the mouth.
The dugong does not have vocal cords but produces sound with its sinuses, on the top of its large head. Well, it sounds like…… a chicken ! What a surprise, for such a large mammal. Its mouth has two incisive teeth like tusks. It has no front teeth : its lips are strong enough to cut the grass.
The sea cow reproduces at a very slow rate : several years before sexual maturity, several years between each birth, one calf per birth. No wonder that it is getting rarer and rarer, with all the poaching, the destruction of its feeding grounds, and the ocean pollution.
Male and female stay together during all the mating season. Gestation is 12 months. The baby is born in the water, where it swims immediately. The mother nurses the young for two years. She holds it at her breast with her pectoral fins. Quite a touching scene. The new born also eats grass immediately after its birth.
It is a great experience to swim with this huge animal. It seems to always smile at you, like a cartoon character. It sometimes looks like a giant foetus. It plays tricks with you, waiting for you to have your back turned to charge you. It also loves to bite flippers and air hoses, and also to grab your legs or heads with its pectoral fins. One gets used to the dugong and it gets used to humans. It plays with photographers and hides from hunters.
Let’s hope that we do not leave to our children a world without dugongs.
The "Stellar Rhytine", large (up to ten meters : thirty feet/8 tons) cousin of the dugong, was discovered in 1751 by the Danish explorer Bering and was thriving from Kamtchatka to Aleutian Islands, was extinct in 1780 ! Harmless and slow, it was speared for its precious fat, meat and tusks. A quarter of a century was enough to eliminate it from living species ! In the eighteenth century, people were not aware of possible extinctions, but nowadays it is inexcusable.
In Espiritu Santo, Vanuatu, in 1992, even though the dugong is "protected" there, a fisherman confessed that he speared one sea cow every week. Since the dugong reproduces so slowly, this is alarming. Scientists estimate that if nothing changes, there will be no dugongs left in ten years time. Its only predator and enemy is the worst one : man.
In his voyage reports of 1707 about Mauritius islands, the French navigator and biologist François Leguat describes his daily encounters with large herds of dugongs : they were excellent meat, tasting like veal and excellent fat ; they were not at all afraid of man and very easy to fish : just jump in the water in the middle of 300 of them, choose, by feeling it, a nice fat one, not too heavy to carry, tie a rope around its tail and drag it out of the water and cut its throat. The dugong dies quickly after that, without a fight. At present, there is not one single sea cow left around these islands.
A serious protection for this still mysterious and adorable specie is a must.