West Indian manatee in the context of "Sirenia"

Manatees (/ˈmænətiːz/, family Trichechidae, genus Trichechus) are large, fully aquatic, mostly herbivorous marine mammals sometimes known as sea cows. There are three accepted living species of Trichechidae, representing three of the four living species in the order Sirenia: the Amazonian manatee (Trichechus inunguis), the West Indian manatee (Trichechus manatus), and the West African manatee (Trichechus senegalensis). They measure up to 4.0 metres (13 ft 1 in) long, weigh as much as 590 kilograms (1,300 lb), and have paddle-like tails.

Manatees are herbivores and eat over 60 different freshwater and saltwater plants. Manatees inhabit the shallow, marshy coastal areas and rivers of the Caribbean Sea, the Gulf of Mexico, the Amazon basin, and West Africa.

Biscayne National Park is a national park of the United States located south of Miami, Florida, in Miami-Dade County. The park preserves Biscayne Bay and its offshore barrier reefs. The shore of the bay is the location of an extensive mangrove forest. The park covers 172,971 acres (69,998.9 ha; 270.3 sq mi; 700.0 km), of which 9,075 acres (3,673 ha) are on land. It includes Elliott Key, the park's largest island and northernmost of the true Florida Keys, formed from fossilized coral reef. The islands farther north in the park are transitional islands of coral and sand. The offshore portion of the park includes the northernmost region of the Florida Reef, one of the largest coral reefs in the world.

Biscayne National Park protects four distinct ecosystems: part of the Florida mangroves along the shoreline, the shallow waters of Biscayne Bay, the coral limestone keys, and the offshore Florida Reef. The shoreline swamps of the mainland and island margins provide a nursery for larval and juvenile fish, molluscs, and crustaceans. The bay waters harbor immature and adult fish, seagrass beds, sponges, soft corals, and manatees. The keys are covered with tropical vegetation including endangered cacti and palms, and their beaches provide nesting grounds for endangered sea turtles. Offshore reefs and waters harbor more than 200 species of fish, pelagic birds, whales, and hard corals. Sixteen endangered species including Schaus' swallowtail butterflies, smalltooth sawfish, manatees, and green and hawksbill sea turtles may be observed in the park. Biscayne also has a small population of threatened American crocodiles and a few American alligators.

Everglades National Park is a United States national park that protects the southern twenty percent of the original Everglades in Florida. The park is the largest tropical wilderness in the United States and the largest wilderness of any kind east of the Mississippi River. An average of one million people visit the park each year. Everglades is the third-largest national park in the contiguous United States after Death Valley and Yellowstone. It was declared a national park in 1947. UNESCO declared the Everglades & Dry Tortugas Biosphere Reserve in 1976 and listed the park as a World Heritage Site in 1979, and the Ramsar Convention included the park on its list of Wetlands of International Importance in 1987. Everglades is one of only three locations in the world to appear on all three lists.

Most national parks preserve unique geographic features; Everglades National Park was the first created to protect a fragile ecosystem. The Everglades are a network of wetlands and forests fed by a river flowing 0.25 miles (0.40 km) per day out of Lake Okeechobee, southwest into Florida Bay. The park is the most significant breeding ground for tropical wading birds in North America and contains the largest mangrove ecosystem in the Western Hemisphere. Thirty-six threatened or protected species inhabit the park, including the Florida panther, the American crocodile, and the West Indian manatee, along with 350 species of birds, 300 species of fresh and saltwater fish, 40 species of mammals, and 50 species of reptiles. The majority of South Florida's fresh water, which is stored in the Biscayne Aquifer, is recharged in the park.