They have two flippers and a paddle-like tail, and are closely related to two land mammals: the elephant and the hyrax. Manatees (Trichechus manatus) communicate with each other via underwater vocalizations.
Range and Habitat of Manatees
Manatees cannot tolerate low temperatures (<65 degrees Fahrenheit), and are thus found in warmer, more tropical waters. In the United States most manatees live in Florida. Between March and November they range throughout Florida's coasts and rivers, and rarely travel as far as North Carolina and Louisiana. However, in the winter manatees concentrate around warmer waters, near springs or even warm water discharge from power plants. They prefer shallow, slow-moving water, and live in fresh, salt, and brackish water. Popular places to view manatees in Florida include Homosassa Springs Wildlife State Park, Blue Springs State Park, and Lee County Manatee Park.
Manatee Behavior
As vegetarians, manatees spend 6 - 8 hours a day foraging for vegetation, when they may surface for air as often as every thirty seconds, and 2 - 12 hours a day are spent resting, when manatees may spend up to twenty minutes submerged between breaths. A manatee eats on average 100 pounds of plants per day, and will feed day or night.
Manatees are both social and solitary. With no natural enemies, they never evolved a protective heirarchical social system; therefore, if they gather, it is often for informal meetings, sometimes feeding or playing together. They are not monogamous, and may breed year round. After a thirteen month gestation period, mothers typically give birth to one calf, weighing between 60 - 70 pounds. Males play no role in raising their young, and the baby is dependent on mom for up to two years. Manatees have low reproductive rates - females are not sexually mature until age five, and may only give birth every 2 - 5 years. Manatees may live over sixty years.
Relatives of the West Indian Manatee
There are three other extant species of the order Sirenia - the Amazonian manatee, West African manatee, and Dugong. The Stellar's Sea Cow was discovered in 1741 in the Bering Straight, reaching 30 feet and weighing 3/5 tons; however, in just 27 years it was hunted to extinction. The remaining four sirenians are classified as either endangered or vulnerable, and may go the way of the Stellar's Sea Cow if precautions are not taken to minimize threats that they face. Many laws have been enacted and organizations exist for the purpose of preserving these magnificent animals for future generations.
Source: "Manatees" by Save the Manatee Club
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