West Indian Manatee Fact File
Wild 28 years
Captive 60 years
The West Indian manatee is a large, bulging creature found moving through the warm waters around the eastern coastline of the Americas. Two subspecies are recognized, the Florida manatee and the Antillean manatee.
Here they spend their day eating up to 15% of their weight in sea grass and other aquatic plants. To help them feed on this they have teeth which are continually replaced throughout their life.
They are strong swimmers which can spend up to 20 minutes at a time under water when they are resting.
Unfortunately they have become threatened by vehicle strikes and hunting which was previously a much larger issue.
Read on to learn more about these marine mammals below.
West Indian manatees have bulging bodies covered by grey skin. The head is broad and boxy with a muzzle which is covered by whiskers. The skin is paler on the underside.
These slow moving animals may become covered by algae. The skin is continually sloughing off which will help to remove this algae.
Their eyes are tiny and the ear is not visible externally.
On either side of the body is a fore flipper which features a rudimentary nail. At the end of the body is a broad, rounded tail fluke which helps to propel them through the water.
An average West Indian manatee will measure up to 4.3m (14ft) long with an average weight of between 200 and 600kg (440-1,320lbs).
West Indian manatees are herbivores feeding primarily on sea grass along with other aquatic plants. Some floating and emergent plants may also be consumed.
Up to a quarter of their body weight in sea grass may be consumed each day.
To help obtain their food they use the maneuverable lips to pull the seagrass out from the sediment.
Due to their diet and need to eat for 8-10 hours each day their teeth continually fall out and are replaced by new ones which grow in behind.
They will drink freshwater.
West Indian manatees live alongside the coastline of the Americas from the southern United States down to Brazil. Their range takes in a number of islands within the Caribbean.
They are considered extinct around the coast of a number of countries including Anguilla; Antigua and Barbuda; Aruba; Barbados; Bonaire, Sint Eustatius and Saba ; Dominica; Grenada; Guadeloupe; Martinique; Montserrat; Saint Barthélemy; Saint Kitts and Nevis; Saint Lucia; Saint Martin (French part); Saint Vincent and the Grenadines and Sint Maarten (Dutch part). They are possible extinct around the Turks and Caicos Islands.
The Florida population require warm water. Large numbers have been seen to congregate at the outlets of power plant thermal outfalls which supply a steady stream of warm water. They will move in to freshwater lagoons during winter.
They lack a coating of insulating body fat and this means they must remain in warm areas of water.
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Mating can occur year round with no set breeding season.
Males and females mate with multiple partners during the breeding season. They may form small herds around breeding with males attempting to pursue the receptive females.
After a gestation period of 13 months the female will give birth to a single calf, or twins on a rare occasion.
At birth the calf will measure 1.2m (4ft) long with a weight of 30kg (66lbs).
Calves spend 18 months with their mother. During this time they nurse milk from their mother. The teats are located under the forelimbs. Within the first three weeks they are able to begin consuming plants.
Females reach sexual maturity by 5 years old compared to the males which reach the achievement at 9 years old.
A calf is produced by the female once every two to five years.
As a mammal the West Indian manatee must surface to breathe. They can remain submerged for between 3 and 5 minutes at a time when swimming. When at rest this may extend out to as long as 20 minutes.
Each day they may spend between 10 and 12 hours asleep.
West Indian manatees are considered to have poor eyesight but have keen hearing and sense of touch.
These animals are social feeding in small groups averaging 20 members. If food is plentiful these may swell to include up to 100 members.
When swimming they are rather maneuverable and can swim upside down along with doing a somersault or roll.
They produce a range of vocalizations including chirps, whistles and squeaks.
Predators and Threats
Adults do not face any major threats. Juveniles are threatened by large sharks.
Boat collisions are seen as the largest threat to the West Indian manatee. Due to being slow swimmers near the shoreline they often come in contact with these animals.
Accidental deaths within flood control structures and entanglement in fishing gear can often cause death.
Manatee hunts were a common occurrence in to the early 1900s.
Despite their aquatic lifestyle the closest relative of the West Indian manatee are actually the elephants and hyraxes.
These animals are nicknamed the sea cow owing to their docile nature and habit of grazing on sea grass. They are also known as the American manatee.
Manatees and dugongs are believed to be behind the early myth of mermaids. This give rise to their scientific name "sirenians" which means "sirens of the sea".
Two subspecies are recognized, the Florida manatees (T. m. latirostris) which live almost exclusively in the warm waters of Florida and a few adjoining states. One has travelled as far as New York.
The Antillean Manatee (T. m. manatus) makes up the population across the rest of their range.
A male manatee is known as the bull while the female is called a cow.
The West Indian manatee is listed by Alabama as the official state marine mammal in 2009.
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