Manatee Factsheet

What is a manatee?

Manatees belong to the order Sirenia that also includes the dugong and the extinct Steller’s sea cow. Three species of manatee exist: West Indian, Amazonian, and West African. The West Indian manatee is divided into two separate subspecies: Florida manatee and Caribbean manatee. They are thought to be distinct subspecies because of the large body of water separating them from one another.

Do manatees have any relatives?

Manatees are distant relatives of elephants (Domning 1986). You might not think they look alike but if you use your imagination, you will notice they share several characteristics. Both manatees and elephants have tough skin, bristle-like hair covering their entire body, teeth that are continuously being replaced and “toe” nails on each forelimb.

Are manatees related to mermaids?

Manatees might not look like mermaids to us, but many years ago sailors mistook manatees for legendary mermaids. Christopher Columbus was the first person to record the sighting of a manatee in the new world and was surprised at the not-so-beautiful "mermaid". Part of the manatee legend remains in the name of their animal order, Sirenia, which comes from the Greek mythical legend of sirens who sang songs to lure ships into rocky shores.

Where are manatees found?

Manatees live in shallow, calm rivers, estuaries, saltwater bays, canals, and coastal areas. Manatees move from fresh to salt water with no problem (Powell 1992). The Florida manatee frequents most areas of Florida. During the summer months a few travel as far north as Virginia and the Carolinas. Manatees can suffer from cold stress in water colder than 68 oF (20 oC) (Powell 1992). In preparation for winter, manatees travel to areas with warm water such as natural springs or man-made power plants. The Florida Power and Light Company has sighted over 300 manatees together enjoying the warm water and plentiful vegetation near the Fort Myers power plant.

How big are manatees?

Manatees are about 4-4.5 feet (1.2-1.4 m) long when they are born and average 60-70 pounds (27-32 kg). Full-grown manatees weigh between 800 to 1,200 pounds (360-545 kg) and reach 10 feet (3.0 m) in length. They can grow to be as large as 3,500 pounds (1590 kg) and 13 feet (4.0 m) in length (Ridgeway 1985)....WOW!

How can I tell the difference between a male and a female manatee?

Male and female manatees are difficult to distinguish. Biologists even have a hard time identifying the sexes. If you can view the underside of a manatee, you will be able to locate the position of their genitals. Males have genitals located closely below their navel. Females have genitals located above the anus. The anus of both males and females is located near the caudal peduncle, the tapered area before the tail. Females are also identified by the presence of a calf nursing from mammaries located under their pectoral fins.

How long can a manatee hold its breath?

Manatees can hold their breath for approximately 20 minutes, however they regularly breathe every few minutes (Ridgeway 1985). Don't worry if you see a manatee go under water and not come directly back to the surface. They often move under water and surface at a different location out of eyesight.

Do manatees leave "footprints"?

When manatees swim they create oval shaped ripples referred to as footprints. This is a great way to spot manatees, especially since they camouflage so well with their surroundings. Keep an eye open for manatee footprints.

Why does algae grow on manatees?

Manatees are slow moving mammals that frequent the water's surface. Algae thrive in wet areas with lots of sunlight, which makes the manatee's back an ideal breeding ground for algae. Would you like to have algae on your body? It may look uncomfortable to us, but manatees don't seem to mind the slimy stuff. Algae may help to block out harmful rays from the sun. Don't forget your algae next time you go catch some sun!

How do manatees care for their young?

The relationship between a mother and baby is the strongest social bond created by manatees. A mother manatee will carry her baby for about 12 months before it is born (Powell 1992). When born, the baby will weigh nearly 66 pounds (30 kg). A baby manatee is called a calf. The calf will stay close to the mother for one to two years to learn travel routes and the location of food, rest areas and warm water refuges. Females generally give birth to a single calf every two to five years (Reynolds 1992).

How many Florida manatees are in the world today?

Manatees and dugongs inhabit warm waters of the Atlantic, Caribbean, Indian, and Pacific Oceans. There are approximately 6,000 Florida manatees in existence. All Sirenians are in danger of extinction. The Steller’s sea cow, discovered in 1741, became extinct 27 years later due to constant hunting pressure (Stejnegar 1887). Steller’s sea cows lived in Arctic waters and reached a length of 26 feet (8 m). Man has hunted manatees, Steller’s sea cows, and dugongs for their meat, blubber, bones and hide.

Does the government protect manatees?

Both the Marine Mammal Protection Act of 1972 and the Endangered Species Act of 1973 protect manatees. It is illegal to harass, hunt, kill, capture, or collect manatees. In 1978, Florida legislature established the Florida Manatee Sanctuary Act that helped to establish speed zones and sanctuary areas. Today there are twenty-two manatee wintering sites in Florida that aid in the protection of this species by not permitting boats, swimmers, or divers in these areas.

CAUTION: Manatees frequent this area.

While boating, you may see signs warning of manatees in the area. The guidelines are provided to protect manatees from humans. About 25% of manatee deaths are caused by boat collisions each year (Ackerman et al 1995). Signs are posted in hopes that boaters will be responsible by watching for manatees and reducing their travel speed in areas where manatees are often found.

Is it okay to give manatees food and water?

Manatees, like many of us, seem to be curious. They appear to seek out humans, but we must think about their well being rather than our own enjoyment. Manatees are herbivores and feed on over 60 species of aquatic plants and algae found in their natural environment. By offering water hoses or lettuce to attract manatees, we are placing them in great danger.

Most of us who have access to a hose near the water live in areas frequented by boats. Basically we are inviting manatees to "play in the traffic”. Manatees have survived successfully without hoses or lettuce for nearly 45 million years. Feeding marine mammals is illegal according to the Marine Mammal Protection Act.

What should I do if I see a manatee?

Enjoy the moment and appreciate their grace and beauty. Do not reach out to the manatee. You may teach him/her that all people are kind and respectful, which is unfortunately not true! The best way to enjoy their company is to observe them from a distance.

What should I do if I find an injured manatee?

The first thing you should do is take a few minutes to observe the manatee. If possible, draw a sketch. Where/what is the injury? Is it affecting his/her ability to move? Are there other manatees in the area? Have you seen the manatee dive or eat? These are just a few of the questions that might be asked by a member of the manatee assessment team. The next step is to call for help by contacting the Florida Fish and Wildlife Conservation Commission at 1-888-404-FWCC. They will notify the appropriate people to assess the situation.

Why are certain manatees tagged?

In order to rescue a manatee, it is often necessary to tag the animal. The tag is connected around the base of the tail and designed to break free if it becomes entangled or caught. There are two types of tags: radio and satellite. Radio tags are used for short term, local tracking. With a radio tag, we can track the manatee to a place where it is safe to rescue. Satellite tags are used for long-term, possibly distant tracking. By satellite tagging manatees, biologists can study and observe the traveling patterns and health of released manatees.

REFERENCES

Scientific Papers:

Ackerman, B.B, S.D. Wright, R.K. Bonde, D.K. Odell and B.J. Banowitz 1995. Trends and patterns in mortality of manatees in Florida 1974-1992. Pages 223-258 in T.S. O’Shea, B.B. Ackerman, H.F. Percival, editors. Population Biology of the Flroida manatee: information and technical report 1. National Biological Services, Ft. Collins, Colorado.

Domning, D.P. and L.C. Hayek. 1986. Interspecific and intraspecific morphological variation in manatees (Sirenia: Tricechus).Marine Mammal Science 2(2): 87-144.

Domning, D.P. 1982. Evolution of manatees: a speculative history.Journal of Paleontology. 56(3): 599-619.

Flamm, R., ET. Al. 2000. Aerial videogrammetry from a tethered airship to assess manatee life- Stage structure. Marine Mammal Science. 16(3): 617-630.

Marsh, H., G.E. Heinsohn and L.M. Marsh. 1984. Breeding cycle, life history and population dynamics of the dugong. Dugong dugon (Sirenia: Dugongidae).Australian Journal of Zoology. 32: 767-788.

Marsh, H., C.A. Beck, and T. Vargo. 1999. Comparison of the capabilities of dugongs and West Indian manatees to masticate sea grass. Marine Mammal Science. 15(1): 250-255.

Marsh, H. 2000. Evaluating management initiatives aimed at reducing the mortality of dugongs in gill and mesh nets in the Great Barrier Reef World Heritage Area. Marine Mammal Science. 16(3): 684-694.

McClenaghan, L.R., and T.J. O’Shea. 1988. Genetic variability in the Florida manatee (Trichechus manatus). Journal of Mammalogy. 69(3): 481-488.

O’Shea, T.J., et al. 1985. An analysis of manatee mortality patterns in Florida, 1976-1981.Journal of Wildlife Management. 49(1): 1-11.

Smith, A., and H. Marsh. 1990. Management of traditional hunting of dugongs {Dugong dugon (Muiller, 1976)} in the northern Great Barrier Reef, Australia. Environmental Magazine. 14(1): 47-55.

Stejneger, L. 1887. How the great northern sea cow (Rytina) became exterminated.The American Naturalist. 21(12): 1047-1054.

Scheffer, V.B. 1973. The last days of the sea cow.Smithsonian. 3:64-67.

U.S. Fish and Wildlife Service. 1989. Florida manatee (Trichechus manatus latirostris) recovery plan. Prep. By the Florida manatee recovery team for the U.S. Fish and Wildlife Service, Atlantic, Georgia.

Books:

Dietz, Tim. 1992. The call of the Siren: Manatees and Dugongs. Fulcrum Pub. Golden, CO. 196 pgs.

Powell, James, 1992, Manatees:Natural History and Conservation, Worldlife Library

Reynolds, John E. III., and Daniel K. Odell. 1991, Manatees and Dugongs. Facts on File. New York. 192 pgs.

Ridgeway, Sam H. and Sir Richard Harrison, eds. 1985. Handbook of Marine Mammals, Volume 3: The Sirenians and Baleen Whales. Academic Press. Orlando, Florida.

Ripple, J. 1999. Manatees and dugongs of the world. Voyager Press.

Loran, W (Sea World Education Department). 1998. “Siren’s Song: The Story of Manatees.”

Van Meter and Victoria Brook. 1987. The West Indian Manatee in Florida.

Florida Power & Light Company, Miami, Florida.

Children’s Books:

Haley, J. 1996. J. Rooker Manatee. Focus Publishing.

Tate, Suzanne. Mary Manatee: A Tale of Sea Cows. 1990. Nags Head Art, Nags Head. 28 pgs.