Rockland hammocks occur only in south Florida and are characterized by tree and shrub species on the northern edge of a range that extends southward into the Caribbean. These communities are sparsely distributed along coastal uplands south of a line from about Vero Beach on the Atlantic coast to Sarasota on the Gulf coast. They occur on many tree islands in the Everglades and on uplands throughout the Florida Keys. This cold-intolerant tropical community has very high plant species diversity, sometimes containing over 35 species of trees and about 65 species of shrubs. Characteristic tropical plants include strangler fig, gumbo-limbo, mastic, bustic, lancewood, ironwoods, poisonwood, pigeon plum, Jamaica dogwood, and Bahama lysiloma. Live oak and cabbage palm are also sometimes found within this community.
Rockland hammocks in the Florida Keys may also contain several plants, including lignum vitae, mahogany, thatch palms, and manchineel, which are extremely rare within the United States.
This conservation asset includes Thorn Scrub.
Florida's rockland hammock habitat is likely to have 58% of the current area inundated by 1 m of sea level rise and 91% inundated by 3 m of sea level rise. Increased soil salinity from saltwater intrusion and increased length of root inundation, increased exposure of salt spray and coastal erosion will lead to changes in species composition and structure as salt intolerant plants decline and plants with higher salt tolerances increase.
Increased temperature along with decreased precipitation and drought could lead to increased wildfire within rockland hammocks.
Drought and heat stress caused by increased temperatures can lead to increased insect outbreaks and habitat degradation.
Increased intensity and/or frequency of storms will cause habitat degradation and loss.
More information about general climate impacts to habitats in Florida.
Rockland hammocks provide critical habitat for many south Florida and Florida Keys endemic species. Many species, including the Key Largo cotton mouse, Key Largo woodrat, Key ringneck snake, Rim rock crowned snake, Florida tree snail and Schaus swallowtail butterfly are dependent upon the rockland hammock community and may face extinction in the wild if/when the habitat is gone. Impacts due to sea level rise, increased exposure to salinity, and storm events could cause the reduction or loss of key host/food plants for these species.
More information about general climate impacts to species in Florida.
This habitat was assessed as part of the Standardized Index of Vulnerability and Value Assessment - Natural Communities (SIVVA).
This habitat is within the top 5 SIVVA most vulnerable natural communities or in the top 5 in most of the SIVVA vulnerability categories.
Read more information about SIVVA natural communities.