The Manatee Animal
Scientists believe there are as few as 2400 manatees alive today. Find out why this animalis protected and how they manage to survive.
The Manatee (genus Trichechus) belongs to three subspecies of large, aquatic mammals that make up the name Trichechidae (order Sirenia). Manatees evolved from four-footed land mammals more than 60 million years ago. Originally inhabiting warm water coastal areas, such as the Caribbean, the Manatee is now a government protected animal, with Scientists calculating that there are as few as 2400 in existance today.
The most common Manatee is knows as the West Indian or sea cow, both of which take refuge off the coast of Florida. This species also resides in the shallow coastal waters of the Caribbean and West Africa. A gentle mammal, the Manatee has no natural enemies. High mortality rates, brought about by fisherman and accidents, have contributed greatly to the population decline in the last century.
Manatees are large somewhat seal-shaped mammals with flat, rounded tails. Adults range in appearance and color. Adult Manatees have brown or gray skin and typically grow to 13 feet in length and weigh more than 3,500 pounds. The Manatee has a small, round face with tiny, wide-set eyes and it's skin is finely wrinkled, allowing for it's top layer to slough off. This helps to reduce the build-up of surface algae and other growths on the Manatee's back and sides, both of which can lead to injury and infection. Just under the Manatee's skin, lies a layer of blubber or fat. This same blubber is found around the outside of the intestines and in much of the Manatee's muscle tissue. Manatees have a thin layer of hair and long, thick whiskers. There are no hind legs on a Manatee and it's front legs or "flippers" are paddle-like in appearance and have three or four nails at the tip. When the Manatee dives under water, it's body naturally protects delicate tissue by drawing inner membranes across the eyeballs and closing nostril valves located on the top of it's snout.
Manatees spend their day feeding on sea grass found at the bottom of the ocean and at the shoreline. Using their flexible upper lip, this mammal is able to tug loose sea plants and guide them into their mouth, where they are vigorously chewed by the Manatees unique teeth. Unlike any other species, the Manatees teeth are continuously replaced. Grinding molars at the back of the jaw wear down, and as they naturally move forward, they fall out, and are replaced by new molars. Scientists speculate that tooth replacement is an adaption to the manatee's diet of plant life, which is often mixed with abrasive roots and sand. The Manatees also have wrinkled front teeth, which help to prevent wear.
There is no evidence to support the thought that there were once millions of Manatees swimming the oceans. In fact, scientists theorize that the Manatee has always been in short supply. Once hunted, thousands of Manatees were killed each year for meat, bone, hides and fat. Manatee hunting was also practiced during prehistoric Indian times, when hides were routinely made into leather shields, cords and shoes. The Manatee's ivory-like bones were believed to be of medicinal value, as well.
Female Manatees are able to reproduce at the age of four. Manatee calves are nursed underwater and remain with their mother for two years after birth. Unlike most mammals, mother and child remain in close contact throughout their entire lives. Though the calf is no longer dependent on the mother after the age of two, Manatees naturally form communities of relatives and travel within this circle.
Manatees communicate through site, sound and touch. Manatees emit a range of sounds underwater that are within human auditory range. Manatees also make sound when they are mating, scared or excited. Manatee cows are able to respond to their calves from more than two hundred feet away.
Manatees are not territorial or aggressive and individuals within a group do not dominate others. Manatees are followers, with one often leading the pack. Manatees usually spend less than five minutes at a time under water. When resting on the ocean floor (which happens daily from 2-12 hours), Manatees surface in an almost trance-like state to refill their lungs.
Over the past century, the Manatee population has diminished greatly due to illegal hunting and cold winters. Poaching is rare today, but the population continues to be threatened by man-made structures, boats and barges, flood-control mechanisms, fishing gear and pollution.