What we call simply "manatees" and scientists call Trichechus manatus are actually the West Indian manatees that live in the rivers, lagoons, estuaries and coastal areas of tropical and subtropical regions of the northwest Atlantic Ocean ranging from the southeastern United States on the north to Brazil on the south.
These big peaceful plant-eaters are an endangered species of marine mammal, according to the U.S. Fish and Wildlife Service. In fact, they are close to extinction, the World Conservation Union says. To make sure that manatees survive in the wild, scientists are studying them to understand how they live and tracking them to find out what they do.
Some 500 to 1,000 manatees live in Belize on the eastern Caribbean Sea coast of Central America. The largest coral barrier reef in the Western Hemisphere is off the coast of Belize. It's 185 miles long. Just inland from the reef, the land rises 3,000 feet with large areas of tropical forest. The subtropical climate has summer highs seldom above 95 degrees Fahrenheit and winter lows rarely below 60 degrees. There is a rainy season in June, July and August.
Tracking West Indian manatees in Belize
Scientists have been tracking West Indian manatees in Belize. Two were observed in 1998 -- one adult male and one adult female. Then, two males and two females were followed in 1999. It turns out that the manatees spent most of their time in the Southern Lagoon Wildlife Sanctuary twenty miles south of Belize City.
Tracking the manatees was accomplished by attaching small radio transmitters to the animals. The transmitters reported location information to satellites overhead which fed the ARGOS tracking system. [how satellite tracking works]
Each day, scientists used data transmitted to them to draw maps of the animals' paths. The results increased their understanding of manatee behavior and assisted wildlife managers in Belize in protecting the animals.
Florida Manatee Tracked from St. Johns River
Manatees in Florida are the same West Indian manatee or Trichechus manatus species. The Florida manatee is an endangered species in the United States. Take the case of Xoshi, a manatee calf rescued in 1995 from a West Palm Beach canal after she was either orphaned or abandoned.
The malnourished Xoshi had abscesses on her body, weighed only 120 lbs. and would have died if she hadn't been nursed back to health at Lowry Park Zoological Gardens in Tampa. Biologists with the U.S. Geological Survey helped release the now 1,300-lb. Xoshi into St. Johns River, northeast of Orlando, on Feb. 22, 2000.
From November through March, manatees leave the colder waters of the St. Johns River for the safety and comfort of the 72-degree blue spring
A conservation fund at an Ohio zoo paid for Xoshi's satellite tracking, which will signal an early warning if the manatee is injured or becomes sick. Visitors at the Cincinnati Zoo and Botanical Garden follow Xoshi's path through Florida's freshwater rivers and lakes on a computer monitor at the zoo's exhibit known as Manatee Springs. [how satellite tracking works]
The U.S. Department of Fish and Wildlife supports critical care for manatees that are injured by boat propellers or that become tangled in fishing lines. Mapping migration patterns of manatees like Xoshi helps researchers know where to slow down boats passing through heavily inhabited areas.
The Florida Caribbean Science Center Sirenia Project of Gainesville, Florida, is a team of scientists from the Florida Caribbean Science Center, Biological Resources Division of the U.S. Geological Survey, and the U.S. Department of the Interior researching West Indian manatees in Florida. The Project also has studied the so-called sirenians elsewhere, including manatees and dugongs in other parts of the world.
Dugongs are herbivorous marine mammals, known to scientists as Dugong dugon. They have flippers for forelimbs and a deeply notched tail fin. They live in tropical coastal waters of the Indian Ocean, Red Sea, and southwest Pacific Ocean.
The West Indian Manatee
The West Indian Manatee was first recorded by Europeans near Hispaniola in 1493. They thought manatees were mythical mermaids.
West Indian manatees like tepid fresh and salt water around 70 degrees, shallow water plants and shallow slow flowing rivers and lagoons.
Adult manatees are 10 to 12 feet long and weigh 1,000-2,000 pounds. They eat as much as 150 pounds of aquatic plants every day. Manatees rest frequently while submerged coming up to breathe every 3 to 5 minutes. Manatees probably live for 50 to 60 years.
Two other branches of the species are the West African manatee and Amazonian manatee. The four closely-related species -- West Indian, West African and Amazonian manatees and dugongs -- are unique in that they are the only plant-eating marine mammals alive today.
All four are threatened by poaching for food, collision with boats, entanglement in fishing nets and loss of feeding habitats. In the United States, thirty percent of the deaths are caused by humans.
SOURCES: U.S. Department of Fish and Wildlife, Florida Caribbean Science Center Sirenia Project, Sirenia Project of the USGS /Biological Resources Division, World Conservation Union, Belize Ministry of Forestry, Save the Manatee Club, Wildlife Conservation Society, Florida Department of Environmental Protection, Wildlife Preservation Trust International, Belize Ministry of Agriculture, Fisheries and Coastal Zone Management, Wildlife Conservation Solution, Cincinnati Enquirer, and Space Satellite Handbook.
Satellites main page ~~ Space Today Online cover ~~ Copyright 2000 Anthony R. Curtis