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The Florida Manatee
Florida Manatee or West Indian Manatee
Trichechus manatus latirostrus
The Florida Manatee, Florida's state marine mammal, is a large aquatic relative of the elephant. They are grayish brown in color and have thick, wrinkled skin on which there is often a growth of algae. Their front flippers help them steer or sometimes crawl through shallow water. They also have powerful flat tails that help propel them through the water. Despite their small eyes and lack of outer ears, manatees are thought to see and hear quite well.
They are gentle giants, that seem to have no fear, nor aggression towards people. They swim in shallow waters, near the surface and are endangered because they often are injured by boats and their props.
The name manati comes from the Taino which are the original peoples of the Caribbean, meaning "breast". They comprise three of the four living species in the order Sirenia, the other being the dugong, which is native to the Eastern Hemisphere. The Sirenia is thought to have evolved from four-legged land mammals over 60 million years ago, with the closest living relatives being the Proboscidea (elephants) and Hyracoidea (hyraxes)." (1)
The photo above is a watercolor called ~Lana's Manatee, by Linda Hoxie. Which started me on the path of learning about the gentle Manatee, and I fell in love with their sweet nature
Just how big are they?
How big is a manatee?
They average a length of ten to twelve feet, and weigh 1,500-1,800 lbs.
Calves are born weighing between 60 and 70 pounds and measuring about three to four feet. They nurse underwater.
What does a Manatee eat, to keep all that weight?
Manatees are herbivores (plant-eaters), feeding on a large variety of submerged, emergent, and floating plants. Seagrass beds and freshwater submerged aquatic vegetation are important feeding sites for manatees.
Manatees can eat 10 - 15% of their body weight in vegetation daily. A 453-kilogram (1,000-pound) manatee, for example, would probably eat between 45-68 kilograms (100 - 150 pounds) of food a day.
These are some of the foods they eat:
Syringodium filiforme/Manatee grass
Thalassia testudinum/Turtle grass
Halodule wrightii/Shoal grass
Ruppia maritima/Widgeon grass
Vallisneria neotropicalis/Tapegrass, Eelgrass
Eichhornia crassipes/Water hyacinth
Pistia stratiotes/Water lettuce
*Non-native, or exotic, vegetation
Just how endangered is the Manatee population in Florida?
The largest population of manatees is found in Florida, where there are over 3,000 individuals.
West Indian manatees have no natural enemies, and it is believed they can live 60 years or more. Many manatee mortalities are human-related. Most human-related manatee mortalities occur from collisions with watercraft. Other causes of human-related manatee mortalities include being crushed and/or drowned in canal locks and flood control structures; ingestion of fish hooks, litter and monofilament line; and entanglement in crab trap lines. Ultimately, however, loss of habitat is the most serious threat facing manatees today. There are approximately 3,000 West Indian manatees left in the United States.
Interesting Manatee Facts
Manatees only have molars to grind their
Manatees chew two times per second.
Manatee teeth are constantly being replaced as
they wear down and fall out.
The intestine of an adult manatee can measure
130 feet long.
Manatees only breath through their nostrils.
Manatee can hold their breath for up to 24
Manatee lungs are 2/3 the length of its body.
A manatee cannot turn its head sideways, it
must turn its whole body.
It takes 13 months for a manatee to be born.
Calves spend two years with their mothers
learning the migration routes.
Where they roam...
Manatees take up residence primarily in Florida's coastal waters during winter. Some individuals migrate as far north as the Carolinas or as far west as Louisiana in summer. In recent years, a manatee traveled to New York and another swam up the Mississippi River!
Behavior and Reproduction
Manatees can be found in the warm waters of shallow rivers, bays, estuaries and coastal waters. Rarely do individuals venture into waters that are below 68 degrees Fahrenheit. Well known for their gentle, slow-moving nature, manatees have also been known to body surf or barrel roll when playing. They normally rest and feed often. Manatees communicate by squealing under water to demonstrate fear, stress or excitement.
The reproductive rate for manatees is slow. Female manatees are not sexually mature until about five years of age, and males are mature at approximately nine years of age. On average, one calf is born every two to five years, and twins are rare. The gestation period is about a year. Mothers nurse their young for one to two years, so a calf may remain dependent on its mother during that time.
Threats and Protection of the Manatee
Destruction and degradation of their coastal and freshwater habitat. The leading known cause of death is by boat strikes; propellers and hulls inflict serious or mortal wounds. Most manatees have a pattern of scars on their backs or tails after surviving collisions with boats. Scientists use these patterns to identify individuals. Manatees are also vulnerable to cold water. They have been found crushed or drowned in flood-control gates and suffer harm from exposure to toxic red tide. In addition, a large number of manatees die from unknown causes each year.
Federally listed as Endangered and state listed as Endangered. *Endangered Species Act; **Marine Mammal Protection Act; Florida Endangered and Threatened Species Act; Florida Administrative Code; Florida Marine Sanctuary Act; ***CITES Appendix 1.
* The Endangered Species Act requires the US federal government to identify species threatened with extinction, identify habitat they need to survive, and help protect both. In doing so, the Act works to ensure the basic health of our natural ecosystems and protect the legacy of conservation we leave to our children and grandchildren.
Marine Mammal Protection Act
The Marine Mammal Protection Act prohibits, with certain exceptions, the take of marine mammals in U.S. waters and by U.S. citizens on the high seas, and the importation of marine mammals and marine mammal products into the U.S.
What can you do to help?
If boating follow these tips:
Wear polarized sunglasses. They can help eliminate the glare of the sun and enable you to see below the water's surface.
Stay in deep water channels when boating. Avoid boating over seagrass beds and shallow areas where manatees might be feeding. However, be aware that manatees also use deep water channels when traveling.
Look for a snout, back, tail, or flipper breaking the surface of the water. A swirl or flat spot on the water is also created by the motion of the manatee's tail when it dives or swims.
If you see a manatee when operating a powerboat, remain a safe distance away -- 50 feet is the suggested minimum. If you want to observe the manatee, cut the motor, but don't drift over the animal.
If you like to jet-ski, water-ski, or participate in high-speed water-sports, choose areas that manatees do not or cannot frequent, such as land-locked lakes or waters well offshore.
Obey posted speed zone signs and keep away from posted manatee sanctuaries.
The propeller scars on Flicker's back (above) are vivid reminders of what can happen
when a manatee meets up with a boat. (Photo courtesy FWCC.)
"Look, but don't touch" is the best policy when swimming or diving. By quietly observing manatees from a distance, you will get a rare opportunity to see the natural behavior of this unique animal. Any other actions might be considered harassment, which is against the law.