The West Indian manatee is usually divided into two or more subspecies (1) the Florida manatee (Trichechus manatus latirostris) and the Antillean or Caribbean manatee (Trichechus manatus manatus). They are distinguished by cranial measurements and geographical distribution. Antillean manatees are smaller in size than Florida manatees. The Antillean or Caribbean manatee can be seen at the DWA.
Description: Antillean manatees are large marine mammals with a walrus-like shaped body that tapers to a wide paddle-shaped tail. Although similar in appearance to seals and walruses, their closest living relatives are the elephant, aardvark and hyrax (a small animal that closely resembles a rodent). They have no hind limbs and each of the two forelimbs or flippers have nails. The gray or gray-brown skin is thick. Hair is scattered sparsely over the body. The flexible upper lip is lined with vibraissae that are very sensitive to touch. Manatees have only six neck vertebrae (most mammals have seven) and cannot move their heads sideways. They must turn their whole body around to see behind.
Size: Antillean manatees reach an approximate length of 12 feet (3.7 m) and can weigh 3,000 pounds (1361 kg). They are typically about 9-10 feet (2.7 – 3 m) long, weighing 1,000 pounds (454 kg).
Behavior: Manatees are slow moving, gentle animals. They rest submerged at the bottom or just below the surface, coming up to breathe on the average of every three to five minutes. When manatees are using a great deal of energy, they may surface to breathe as often as every 30 seconds. When resting, manatees have been known to stay submerged for up to 20 minutes. They usually swim at speeds of 3 – 5 miles (4.8 – 8 km) per hour, but can swim faster (up to 20 miles or 32 km per hour) for short distances. The paddle-shaped tail moves in an up-and-down motion to propel through the water and the two front flippers help steer and gather food.
Diet: Manatees are plant eaters (herbivores) and can consume 10-15% of their body weight in vegetation each day.
Senses: The cloudiness of the shallow water where they live often prevents them from seeing long distances. Small, well-developed eyes have no eyelids and close in a circular motion, somewhat like an aperture on cameras. A lid-like membrane closes over the eye for protection when under- water. Manatees have no external ears. Tiny ear openings are located behind the eyes. Hearing is not very good at low frequencies and this is a problem since slow moving boats produce low frequency sounds. Manatees possess highly sensitive hairs spaced widely apart over their body. Like the coarse whiskers on their top lip, these hairs provide information about their surroundings.
Communication: Manatees communicate through a series of vocalizations that are described as chirps or squeaks, particularly between mothers and calves.
Reproduction: Females are believed to be sexually mature at about five years of age; males at nine or ten years. One calf is normally born every two to five years. Calves can swim to the surface for air immediately after birth. Manatees have no storage sacs for their milk glands, therefore the calf must nurse frequently, getting milk from a pair of nipples, one under each pectoral flipper. Mothers and calves form a strong bond and will stay together for 18 months.
Habitat/range: Antillean manatees inhabit the coast and estuaries of the Atlantic coast of Mexico, Central and northern South America. They can also be found in the waters surrounding the Greater Antilles. There are historical reports of the Antillean manatee off the coast of Texas.
Status: All manatees are endangered and protected by law. CITES Appendix I; IUCN VU (Vulnerable).