The Everglades is a two million acre wetland ecosystem that reaches from central Florida, near Orlando, all the way south to Florida Bay. During the wet season, Lake Okeechobee overflows, releasing water into a very slow moving, shallow river dominated by sawgrass marsh--dubbed the "river of grass." The water flows southward, passing through diverse habitats, including cypress swamps, wet prairie and mangroves, until it reaches Everglades National Park and eventually Florida Bay.
Originally, the Greater Everglades Ecosystem had a large diversity of habitats connected by wetlands and water bodies. Since the 1800's, human actions have been altering the Everglades landscape. Water diversions and flood control projects cut water flows and connections between wetlands throughout the Everglades. Combined with agricultural and urban development, the size of the Everglades has decreased dramatically.
People and the Everglades
The Everglades are surrounded by human development, including the cities of Miami and Ft. Lauderdale. Its wetlands and wildlife draw large numbers of birders, anglers, boaters and other outdoor enthusiasts.
The Everglades also provide critical, and often undervalued, services to people, called ecosystem services. The waters of the Everglades ecosystem support agriculture and provide drinking water for south Florida. The wetlands improve water quality by filtering out pollutants and absorbing excess nutrients, replenish aquifers, and reduce flooding.
Wildlife in the Everglades
The Everglades is internationally known for its extraordinary wildlife--from Florida panthers, to crocodiles, manatees, and a huge host of birds such as roseate spoonbills, egrets, and wood storks.
Plants: The diversity of Everglades' habitats means there's also a great diversity of plants. There are wetland plants from sawgrass and bladderwort to cypress and mangrove trees. There are pine trees, hardwoods, and even beautiful orchids.
Birds: Over 350 bird species can be found in Everglades National Park alone. The Everglades is known for its many wading birds, such as white and glossy ibises, roseate spoonbills, egrets, herons and wood storks, but it also hosts huge numbers of smaller migratory birds. Some species, such as the snail kite, wood stork and Cape Sable seaside sparrow have become endangered species.
Reptiles: Both alligators and crocodiles live in the Everglades and are sometimes mistaken for each other. American alligators like deep, freshwater channels of water called sloughs and wet prairie, where they dig out ponds for nesting. The American crocodile lives in the coastal mangroves and Florida Bay. Everglades National Park has 27 different kinds of snakes alone.
Mammals: The Everglades' most endangered animal, a mammal, is the Florida panther, of which about 80 now survive. Other well-know Everglades mammals are water-dwellers--the West Indian manatee, which is also endangered, and the bottlenose dolphin.
Threats to the Everglades
When an ecosystem is out of balance and native plants and animals are struggling, species from other parts of the world can take advantage of the changed conditions to establish themselves. Some introduce species become a small part of the landscape, while others thrive at the expense of native plants and wildlife. When an introduced species puts additional stresses on native wildlife and threatens habitats, it is called an invasive species.
An invasive species is able to spread throughout new ecosystems, because it doesn't have the natural predators from its native land to keep it in check. Once they've become established, these invaders are hard to stop. The Everglades is being threatened by numerous plant and animal invaders.
Invasive species in the Florida Everglades were introduced both on purpose and by accident.
- Altering water flows and the natural pattern of wildfires allowed exotic plants, such as the Brazilian peppertree, Chinese privet, melaleuca and Old World climbing fern to invade. 1.5 million acres of the Everglades have been invaded by nonnative plants.
- The Burmese python is breeding throughout the park after being released by pet-owners who could not take care of large snakes.
- Nile monitor and Cuban treefrog are both animal invaders.
Animal invaders prey on or compete with native species. The Cuban treefrog eats smaller native frogs, while the Nile monitor eats burrowing owls and crocodile eggs. Burmese pythons have even been known to prey on alligators!
Restoring the Everglades ecosystem will help to prevent new invasions and keep established invasive species in check. The Comprehensive Everglades Restoration Plan was approved in 2000. It is intended to restore, protect and preserve the Everglades by capturing fresh water that now flows unused to the ocean and the gulf and redirect it to areas that need it most for environmental restoration.
National Wildlife Magazine Articles:
The Crocodiles Power Play
Everglades Cooperative Invasive Species Management Area
Comprehensive Everglades Restoration Plan
Everglades National Park
South Florida Water Management District-Everglades and Florida Bay
U.S. Fish & Wildlife Service South Florida Ecological Services Office