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Have you ever heard of the Irrawaddy Dolphin? Have you ever seen one? If not, you are far from alone. Few people, even in its native Australia, have come face to face with this elusive creature of the deep. This despite that the dolphin roams over a large area of the South Pacific, from India’s Bay of Bengal through to the Malay Archipelago and northern Australia.
The Irrawady Dolphin was first categorized by man in the late 19th Century. Zoologist John Anderson saw scores of the bluish – gray dolphin, with its round, beakless head in the Irrawaddy River in what was then Burma. It was he who gave them the name Irrawaddy Dolphin.
Why is the Irrawaddy so rarely seen? Well, they thrive in hot and humid coastal, estuary and river regions. Their home is often flanked by mud, mangroves, clouds of mosquitoes and even crocodiles. Such places are rather inhospitable to human visitors. On top of this, the water in these regions is generally murky. So, if you were able to get into his environment, the only time you’d see an Irrawaddy was when he surfaced for air. Even then he’d keep a low profile. Only a small part of his back would appear out of the water. In addition his dorsal fin is very small in comparison to other dolphins.
The best place to see the Irrawaddy is, not surprisingly, along the Irrawaddy River in Myanmar. Fishermen and riverboat workers along the river often see the dolphin playing in the water, even squirting jets of water from their mouths like water fountains. In Australian waters, the Irrawaddy ranges along the west coast, around the top of the continent, and down the east coast. They are usually seen in groups numbering fewer than six, but occasionally up to fifteen. They live near land. Compared to other dolphins they are rather slow swimmers. Because of the inhospitability of their domain, researchers have found it difficult to study the Irrawaddy. However, live Irrawadies have been studied in the Jaya Ancol Oceanarium in Djakarta, Indonesia.
The first question to be answered was where exactly did the Irrawaddy fit into the whale-dolphin family tree. Was the Irrawaddy, in actual fact, a dolphin or was it a whale? Obviously they have much in common with dolphins. Yet in form they could almost pass for a smaller version of the Arctic beluga whale. Even their unusually flexible neck is very similar to that of the beluga whale. When analysed feature for feature, however, the weight of evidence falls on the side of the dolphin.
At birth the Irrawaddy dolphin calf is about three feet long and weighs some twenty six pounds. The male grows to about nine feet and the female to about eight and a half feet. The dolphin has been known to live for up to twenty eight years. The Irrawaddy feeds on such things as squid, shrimp, prawns and fish, particularly those that live on the bottom of the ocean. Like other dolphins, the Irrawaddy emits a distinctive clicking noise. It is believed that this is done to echo-locate the prey of the dolphin.
Scientists are unsure how many Irrawaddy there are left in the world. There is, however, a growing concern that there is a real threat to the future of this dolphin. A large part of the problem is that massive logging operations have led to the polluting and silting of rivers. In Australia, much of the Irrawaddy’s territory remains relatively uninhabited by humans. But in the more attractive areas on the east coast, urbanization and tourism have taken their toll. Another danger to the Irrawaddy are the fishing and shark nets set near beaches to protect swimmers. Overfishing of the food supply of the Irrawaddy also has a detrimental effect on their numbers. Still the greatest threat to the survival of the Irrawaddy comes from the growing tide of pollutants that are spewed into the oceans, rivers and estuaries. Among the worst pollutants are synthetic organic compounds that tend to persist in the environment. These are used in electronic components, paints, lubricants, coatings for wood and metal and other products.
To combat these threats, the Australian Nature Conservation Agency is working to make the Irrawaddy a primary species in public awareness programs aimed at engendering a respect and concern for the plight of this amazing creature of the deep.
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