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Show Nearly extinct manatee receiving heliD O JL .( - . ... - i p ( 1 1 1 1 1! A mother manatee and calf swim peacefully in a large holding pond before they are released into a man-made man-made lake. After being nearly hunted III tfH4 to extinction for its durable hide and delectable meat, the manatee is receiving help from area researchers. To maintain this size, the strictly herbivorous animals devour large amounts of such aquatic plants as sea grasses and water hyacinths, a trait which some ecologists believe could be used to control undesired aquatic vegetation that frequently chokes tropical irrigation canals, lakes and waterways. However, unlike the Florida manatee, which has been studied directly by scientists in its native habitat, the Amazonian manatee is extremely difficult to find and observe. ob-serve. "They are shy creatures and are usually completely submerged in the water," Montgomery said. "When they come up to breathe, all you can see is a set of nostrils. Moreover, visibility in the muddy waters of the Amazon and its major tributary systems where they live is only three to six feet at most." To solve this problem, Montgomery and Best developed a method to keep track of manatee by using radio transmitters. Montgomery had previously carried out extensive radio-tracking studies of terrestrial mammals, and Best had been working since 1976 on methods for rearing and maintaining manatee in captivity. This collaboration resulted in a successful demonstration demon-stration that an Amazonian manatee could be captured, held in captivity, fitted with a radio transmitter, released unharmed into native waters and folowed closely for a relatively long period of time. This mini-field study provided the underpinning un-derpinning for a prototype manatee relocation project which began late last year. With the cooperation of Amazonian natives, Best, Magnussen, Montgomery and their colleauges traveled upriver from Manaus to capture manatee whch had become stranded in areas where the water levels were low because of drought or because the water had been dirverted to other purposes. Left to their own devices, the docile manatee, which do not defend themselves even when attacked, would undoubtedly become the prey of hunters. In a series of three trips, the scientists netted 19 animals and brought them back to Manaus by boat. The manatee spent the four-and-a-half day boat ride peacefully lazing about in makeshift make-shift swimming pools. "These animals are a pleasure to work with," Montgomery said. "Although they wouldn't win any beauty contests, they are endearing, in-teresting in-teresting and nonaggressive animals. They act as if they enjoy being handled. Anyone who works with them likes them immediately." From Manaus, the manatee traveled again by boat, for three-and-a-half days, to Santarem, a town located near the newly formed, 21,242-acre 21,242-acre tropical Lake Curua-una, Curua-una, created by Brazil's massive hydroelectric development along the Amazon. There, each animal was weighed, measured and examined, and a miniature radio transmitter tran-smitter was fastened as a collar around the narrow portion of the animal's body above its terminal fin. This past spring, the animals took a final two-and-a-half-hour truck ride to Lake Curua-una, where they were released into their new home. For the next several years, the whereabouts and habits of these manatee and as many as 30 additional animals that will be captured and relocated will' be followed by scientists, who will track the animals via radio signals transmitted from their collars.' The signals will be monitored with the help of antennas mounted on small aluminum boats in the lake. "By following the animals daily for long periods of time," Montgomery Mon-tgomery s said, "we hope to f find out where they live in the lake and what kinds and how much vegetation they eat. In about a year or so, we will use t the radio signals to find and recapture the animals. This will allow us to determine their weight g gain and general Natives of South American take home a manatee they have captured alive. Rather than killing it for food, they are taking it by boat to Manaus, where it will be studied. - I 1 ' Jr , - ' " f health. Young manatee in the lake will be captured and marked, and in this way we can monitor the growth of the population." Montgomery, Best and other scientists are hopeful that the relocated manatee will thrive and reproduce in the man-made man-made lake. If things go as planned, the manatee will also keep the lake clear of unwanted vegetation. Montgomery admitted that he would love to see the manatee as plentiful as in the days when sailors, too long at sea, mistook them for mermaids. mer-maids. "It will probably be many years before we know whether we have made an impact," he said. "But right now, the manatee can use all the help it can get." A manatee calf soulfully leans its bewhiskered face along the edge of a holding pond before being weighed, having a radio transmitter attached and being released. By MADELEINE JACOBS Smithsonian News Service I Nearly hunted to exjunction ex-junction for its durable I hide and delectable meat, I the Amazonian manatee, la gentle, homely aquatic I mammal with no known I enemies except man, I may soon be making a I comeback in its native I waters. I The endangered I manatee i is getting a I timely assist from I scientists at the National I Institute for Amazonian I Research (INPA), based I in Manaus, Brazil, in the I heart of the world's I largest river basin, and I the Smithsonian Tropical I Research Institute, I located in the Republic of I Panama. I These researchers, I with support from the I Brazilian national I electric company, I ElectroBras, are hoping I to breed manatee in the I warm waters and lush I vegetation of man-made I tropical lakes formed I from hydroelectric I projects on tributaries of I the Amazon River. The I "home-grown" manatee I would then be used to I restock areas where the I animal's populations I have been depleted by I hunting. I The much-publicized I plight of the Florida I manatee, whose once-I once-I plentiful herds have I dwindled to only 1,000 I animals, has over-I over-I shadowed the crisis I confronting its South I American cousin, whose I numbers have been I greatly reduced by years I of intense commercial I exploitation and by the I loss of the creature's I natural habitat resulting I from industrial I development. I Between 1935 and 1954, I an estimated 400,000 I manatee skins I ignominiously destined to I become machine belts I were exported from I Amazonia through the I river port of Manaus. I Manatee have been I legally protected as I endangered animals in I Brazil since 1967. But I even now, because of the I vast areas involved I (Brazil occupies half of I the South American I continent), the inac-I inac-I cessibility o of much of I the terrain and the few I game wardens available II to e enforce the laws, I manatee continue to be killed, primarily for their meat. I Protection of the 1 Amazonian manatee also I has been hampered by a 1 lack of information about 1 their ecology and life 1 history, according to Dr. I G. Gene Montgomery, a I biologist at the Smithsonian Tropical I Research Institute who is working 'on the manatee conservation project with his Brazilian colleagues, Drs. Robin C. Best and Bill Magnussen at INPA. This much is know : The Amazonian manatee lives in fresh water in lakes, flood plains and long river channels wherever there is enough vegetation for them to feed. As adults, the torpedo-shaped, round- tailed creatures may grow to ten feet in length and may weigh up to 2,000 pounds. |