An ecosystem is a community of plants and animals that live together. South Florida is home to many different ecosystems including coral reefs, dunes, marshes, swamps, hardwood hammocks, mangroves, pinelands and scrubs. What type of ecosystem will exist in a certain area is determined by how often fire occurs in an area, and changes in elevation (in some cases, only inches), water salinity and soil type.

Coral Reefs Coral is a collection of small, individual coral animals called polyps. Polyps secrete a limestone cup around themselves and as they grow they come into contact with other polyps, forming a living reef. When the polyps die, new polyps build their home on top of the limestone skeletons. As you can imagine, coral reefs take a long time to grow! Zooxanthellae are tiny plants (algae) that grow in the tissues of the coral polyps. They depend on coral for food and protection and the coral depend on zooxanthellae for oxygen and food. Coral reefs can contain many different species of plants and animals.

Star and Staghorn Coral found in the Florida Keys. Click on the picture to open a larger photo.

Click on the picture to open a larger photo.

Dunes Dunes are created by dune grasses, which trap sand grains being moved across the beach by wind. Dunes stabilize the mounds of sand that protect the coast against winds and pounding tides. The vegetation found within Florida's dunes varies and is dependent upon many factors including storm waves, windblown sand, salt spray, soil type and climate (Myers and Ewel, 1991). Florida beaches are important nesting sites for sea turtles and shore birds.

Freshwater Marshes Freshwater marshes are generally wetlands with an open expanse of grasses and other grass-like plants. Standing water occurs here for much of the year. Marshes generally contain few if any trees and shrubs. They act as natural filters. As water passes over the marsh, water flow is slowed down and suspended particles settle out. Animals found in the marsh can include fish, frogs, snakes, alligators, white-tailed deer, the Florida panther and other mammals. Many waterbirds and wading birds nest and forage (search for food) in marshes as well.

Click on the picture to open a larger photo.

Click on the picture to open a larger photo.

Freshwater Swamps Freshwater swamps are generally wet, wooded areas where standing water occurs for at least part of the year. While the freshwater swamp seen in this picture is dominated by cypress trees, other freshwater swamps found in Florida can be dominated by bay trees (i.e. sweetbay, sweet gum) or hardwoods (i.e. oak, elm, red maple). Other plants found in swamps include epiphytes ("air plants") growing from trees, vines and ferns. Many animals spend part of their lives in the swamp, moving as water levels rise and fall. Wood storks, herons, many other birds, otters, black bear, and the Florida panther are only a few of the animals that find food, homes and nesting sites in Florida's swamps.

Hardwood Hammocks Hardwood hammocks are localized, thick stands of hardwood trees that can grow on natural rises of only a few inches in the land. In South Florida, hammocks can be found in marshes, pinelands and mangrove swamps. Hammocks may contain many different species of trees such as the sabal palm, live oak, red maple, mahogany, gumbo limbo and cocoplum. Many types of epiphytes, "air plants", and ferns can be found here as well. Wildlife found in hammocks can include tree snails, raccoons, opossums, birds, snakes, lizards, tree frogs and large animals such as the Florida panther, bobcats and deer.

Click on the picture to open a larger photo.

Click on the picture to open a larger photo.

Mangroves Three species of mangroves are found in Florida: the red mangrove, black mangrove and white mangrove. Typically, red mangroves grow along the water's edge, black mangroves grow on slightly higher elevations than the red mangrove and white mangroves grow upland from the red and black. Mangroves grow in flooded saltwater areas and are salt tolerant. Mangroves provide protected habitat, breeding grounds and nursery areas to many land and marine animals. Mangroves also provide shoreline protection from wind, waves and floods.

Pinelands Pinelands are the most common plant communities in Florida. Pinelands are found on nearly level land. Soils are coarse and poorly drained. Longleaf pine and slash pines are the dominant trees in pinelands. Understory plants commonly include saw palmettos, wildflowers and ferns. Plants that grow in the pinelands must be resistant to fire because areas such as these are maintained by fire. Fires are beneficial to the pines as young pine seedlings require lots of sunlight to survive, and the fires destroy their hardwood competitors. When fires occur, hardwood seedlings and other understory plants are affected, while the thick bark of the pine resists fire damage. Without fires, hardwoods would eventually overshadow the pines and a hardwood hammock would emerge. Wildlife commonly found in pinelands includes deer, squirrels, bobcats, skunks, opossums, raccoons, birds, snakes and tortoises.

Click on the picture to open a larger photo.

Click on the picture to open a larger photo.

Scrubs Generally, scrubs are communities that are mostly pinewoods with a thick understory of oaks and saw palmetto. Scrubs are found in well-drained, nutrient-poor, sandy soils. Plants that grow here have adapted to dry conditions. Fires play an important role in the life of scrubs. Without fires, a hardwood forest of oak will develop. Animals that live in the scrub are adapted to hot, desert-like conditions. Gopher tortoises, scrub jays, lizards, insects and spiders are commonly found here.

An Ecosystems of South Florida poster is available.

Want to learn more about Florida's ecosystems? Please visit:

• The Living Everglades - Everglades Information: Habitats (from the South Florida Water Management District website)
  Descriptions and photos of some of Florida's common natural areas.

• Habitats of Everglades National Park (from the National Park Service)
  Descriptions of habitats found within Everglades National Park.

To top of the page

Next: Critters that make their home in South Florida

U.S. Department of the Interior, U.S. Geological Survey, Center for Coastal Geology
This page is: http://snowball /virtual_tour/kids/ecosys.html
Comments and suggestions? Contact: Heather Henkel - Webmaster
Last updated: 22 July, 2003 @ 05:33 PM (KP)