Manatees are found in shallow, slow-moving rivers, bays, estuaries, and coastal water ecosystems. They can live in fresh, brackish, or salt water. These habitats provide them with sheltered living and breeding areas, a steady, easily obtainable food supply, and warm water - all of which manatees need to survive.

Range The United States manatee population is concentrated primarily in Florida. Manatees are susceptible to cold-related disease and, in the winter, congregate near natural springs, which have a constant 72 degree F. temperature, or warm effluents of power plants or other industrial outfalls. Water temperatures below 68 degrees F. usually cause manatees to move into these warmer refuge areas. Individual manatees often return to the same wintering areas year after year. Between late March and November manatees migrate freely around Florida's rivers and coastal waters. A few may range as far north as the Carolinas and as far west as Louisiana during the summer months, but these sightings are rare.

Food Manatees are herbivores, feeding on a large variety of submerged, emergent, and floating plants. They can eat 10-15% of their body weight of vegetation daily. Seagrass beds are important feeding sites. Many of these coastal and estuarine feeding areas are particularly vulnerable to destruction by dredge and fill activities, surface water run-off from nearby construction sites or agricultural lands, herbicide spraying, and prop dredging. While coastal and estuarine vegetation is declining, quite another problem is occurring in our fresh water bodies. In recent years, Florida has experienced an influx of exotic species, including freshwater vegetation. Because exotic species originate elsewhere and are not native to Florida, they have no natural enemies here, and consequently can grow unchecked. Our fresh water bodies have become clogged with such vegetation. Manatees eat exotic plants, but there aren't enough manatees to control these unwanted plants in all the areas where they are found. Some favorite foods of the manatees in Florida include:

Marine Vegetation Syringodium filiforme / Manatee grass Thalassia testudina / Turtle grass Halodule beaudettei / Shoal grass Ruppia maritima / Widgeon grass

Freshwater Vegetation Hydrilla verticillata / Hydrilla Vallisneria neotropicalis / Tapegrass, Eelgrass Eichornia crassipes / Water hyacinth Pistia stratiotes / Water lettuce

The Four necessary Elements of Habitat Suitable habitat for the manatee (as well as for any living being) must provide four basic elements: Food: Considering the amount that manatees eat, suitable habitat must provide an abundance of aquatic plants to sustain the manatees using an area. Water: Manatee intake of water occurs while eating aquatic plants as well as drinking. Recent research suggests that manatees in salt water do not need to drink fresh water for extended periods. This may explain why manatees can go so easily from fresh to salt water environments. Currently, researchers are studying manatees in salt water who are fed a natural sea grass diet to analyze how these animals deal with a strictly marine habitat. Space: Manatees require space to move about. They are migratory and the space (range) they require is influenced by seasonal change. Travel corridors, or passageways, are necessary for the manatee to move back and forth between summer and winter habitats. (It has been documented that many manatees have preferred habitats that they return to year after year.) Shelter: Manatees must have safe, protected areas - away from harassment, boat traffic, strong current, etc. If any of the four elements are missing, manatees cannot survive. And, indeed, manatees are dying as a result of the loss of these elements. Shelter, for one, continues to be harder and harder to find. As a result, manatees are using less favorable habitat where high boat traffic and harassment occur.

Habitat Activities Arrange a field trip to a manatee sanctuary (Homosassa Springs Wildlife State Park would be an excellent choice or see listings on Public Arareness page) sometime during the winter months, or visit a marine park which displays manatees or other marine animals to help students experience these animals first hand. Discuss how climate restricts a manatee's movements. Why must manatees live in certain areas? People can buy or make things they need to eat or keep warm. Manatees and other wildlife must rely on natural resources found in their environment. Where does the manatee find these resources? Compare the manatee with other animals that share its habitat. What characteristics help each animal live in its particular niche? Compare the manatee with other animals that live in different environments such as land animals. How is each adapted to its particular lifestyle? Make a plaster cast of a manatee habitat such as a spring run. Include details like grasses, trees, fish, access to a river, sanctuary signs, boats, rangers, etc., or draw posters of the manatee in its habitat. Have students find or draw pictures of plants manatees might eat. Manatees and people share habitat, too. The riverways that manatees depend on for survival are also used by people for transportation, commercial fishing, and recreation. Can people share habitat with manatees and all wildlife without degrading the quality of Florida's natural resources? Have students list other animals that might share the manatee's habitat. For example, fish, otters, turtles, insects, snakes, alligators, and birds all share Florida's river systems. Draw pictures of them sharing this habitat. Florida has a special responsibility to protect the manatee, which depends almost entirely on the quality and stability of the state's natural resources. Have students discuss this responsibility. What can we do to insure the sound management of resources for the manatee? Discuss herbivores, carnivores, and omnivores. Manatees are herbivores. What do other aquatic animals eat? Have students list several animals and identify them as herbivores, carnivores, or omnivores. Take each of the four necessary elements of habitat, one at a time, and discuss why each is necessary for manatee survival. (Example: Some people believe that saving the manatee will require moving the population to a restricted area, away from the areas most used by humans. This certainly takes care of shelter, but it restricts space. What would happen in winter when the manatee needed a warm water refuge and couldn't get to it? Or, what about food supply in a restricted area with a large number of manatees - would it last?) A major threat to the manatee is the loss of habitat. The Indian River Lagoon on Florida's east coast has experienced substantial losses. For example, it has lost 80% of its mangrove marshes through impoundment for mosquito control purposes, and 30% of its seagrass beds. Have students draw a picture representing the habitat 20 years ago, then have them cross out a portion to represent the percentage lost. Discuss the consequences of this habitat loss for manatees and other species.

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