Boundaries

Restricted to the Gulf-Atlantic Coastal physiographic province, this ecoregion covers southeastern Georgia and all of peninsular Florida. The northern boundary of the ecoregion is defined largely by the watershed of the Suwannee River, flowing from Georgia through Florida to the Gulf, and several smaller rivers that flow into the Gulf of Mexico or the Atlantic Ocean. Among these are the Ochlockonee and the Saltilla.

Topography

The ecoregion lies within the Coastal Plain geomorphic province and is generally flat and low-lying. Most areas do not exceed 30 m elevation, although areas exceed 100 m in a small northeastern section of the ecoregion (McNab & Avers 1994).

Freshwater habitats

This ecoregion is characterized by a variety of aquatic habitats that is virtually unequaled elsewhere in North America. Though intermittent streams are few, there are abundant marshes, swamps, mangrove swamps, ponds and lakes, springs, and large rivers. In fact, Florida in total has more artesian springs than any other region of the world, with one hundred major springs occurring beside or within the channels of the Suwannee River or its main tributaries alone (Carr 1994). The lower reaches of all the rivers that flow into the Atlantic or Gulf of Mexico experience the effects of tides and are often inhabited by both euryhaline (salt-tolerant) freshwater and marine species, including tropical peripheral species (Gilbert 1992).

The Everglades, located at the southern tip of peninsular Florida, is one of the most distinct wetlands in the world. It has been called “River of Grass” (Douglas 1947), describing the slow flow of water over shallow, broad tracts of marsh. In addition to the importance of sheet flow, groundwater connections of the Everglades to Lake Okeechobee, the second largest freshwater lake entirely within the U.S., are also essential for the maintenance of the wetland (Ricketts et al. 1999).

Terrestrial habitats

A majority of the ecoregion is defined as southeastern conifer forests, and is comprised of vegetation types that grade from long-leaf pine forests (Pinus palustris) to pine savannas and xeric hardwood communities (Christensen 1988; Myers 1985). The once-dominant long-leaf pine and wiregrass (Aristida stricta) communities are maintained by high frequency, low-intensity fire regimes (Ricketts et al. 1999). The Everglades encompasses the southern tip of the ecoregion, and includes sawgrass habitats interspersed with swamp forest dominated by red bay (Persea borbonia), pond apple (Annona glabra) forests, Cypress (Taxodium ascendans) forests, and hardwood hammocks (Ricketts et al. 1999).

Description of endemic fishes

The flagfish (Jordanella floridae) and Suwannee bass (Micropterus notius) are the only two endemics within the Florida Peninsula.

Justification for delineation

Ecoregion boundaries are taken from Abell et al. (2000) and are based on subregions defined by Maxwell et al. (1995).