The West Indian manatee is one of three manatees and four sea cows (along with the dugong) alive today. This species lives in warm waters of the western Atlantic Ocean, and in addition to spending most of its time in shallow coastal seas, it occasionally enters freshwater – particularly warm springs – where it spends some of the colder winter months.
The West Indian manatee, like all sea cows, is herbivorous. It primarily grazes on sea grasses and therefore spends most of its time in sea grass beds. As in most herbivores, this manatee’s brain is very small compared to its body size, likely because it does not have to develop complex hunting strategies to capture prey. It uses its thick, highly maneuverable lips to pull seagrass from the soft sediments in which it grows.
Like all mammals, West Indian manatees reproduce via internal fertilization and give birth to large young, which they nurse. A mother-calf pair will stay together for as long as two years before the calf develops some independence. Adult West Indian manatees have no natural predators, but juveniles may be eaten by large, coastal sharks.
West Indian manatees prefer warm water and undergo long, annual migrations between warm, winter areas and productive, summer areas. Wintering grounds include some warm springs, coastal seas in the tropics, and artificial warm areas caused by coastal power plants.
There are two recognized subspecies of West Indian manatees: the Florida manatee (Trichechus manatus latirostris) and the Antillean manatee (Trichechus manatus manatus). The other two distinct species of manatees are found in Brazil and in Africa.
The West Indian manatee has some or complete legal protection throughout most of its range, but it is still hunted in some places and is threatened by habitat destruction, collision with boats, and accidental capture in fisheries targeting other species throughout most of its range. Boat collisions are probably the most significant threat to this species, as they are common in recreational boat areas and are slow, poor swimmers. Populations are depleted in some places and regionally extinct in others, and scientists believe the West Indian manatee to be vulnerable to extinction. Without careful management of the human activities that threaten this species, it could be lost from more places.
1. West Indian manatees weigh up to 1,200 pounds (544 kg) and reach about 10 feet (3 m) in length.1
2. West Indian manatees eat up 15 percent of their body weight every day in sea grass and vegetation. That can be up to 150 pounds of food a day.
3. West Indian manatees migrate to warmer waters in the winter because exposure to temperatures lower than 68 degrees Fahrenheit can be deadly.
4. West Indian manatees occasionally wander into freshwater rivers and springs.
5. West Indian manatees spend 10 to 12 hours a day sleeping.
6. West Indian manatees can hold their breath for up to 20 minutes underwater, but usually surface every few minutes for air.
7. West Indian manatees swim at an average speed of 3 to 5 miles per hour (4.8-8 km per hour).2
Oceana joined forces with Sailors for the Sea, an ocean conservation organization dedicated to educating and engaging the world’s boating community. Sailors for the Sea developed the KELP (Kids Environmental Lesson Plans) program to create the next generation of ocean stewards. Click here or below to download hands-on marine science activities for kids.