This conservation asset was not assessed for vulnerability
A coral reef is an epibenthic community; a concentrated topographic complex of massive corals and other sessile organisms (algae, bryozoans) that build calcium carbonate (limestone) skeletons. The structural complexity provides habitat for a highly diverse flora and fauna that live all or portions of their lives on coral reefs. Two major Coral Reef types are recognized: patch reefs and offshore bank reefs.
Bank Reefs are further defined by zones (e.g., reef flat, spur and groove). The types of coral reefs found off the coast of Florida include the shallow-wave resistant reefs in the region from Dry Tortugas to Martin County; deeper (30-130 ft.; 10-40 m) reefs in the same region; the Oculina Banks seaward of Palm Beach to Vero Beach. Deep water (165-265 ft.; 50-80 m) structures such as Pulley Ridge and the Florida Middle Grounds occur along the west Florida shelf break in federal waters.
Hard Bottom is characterized as mixed communities of algae, sponges, octocorals and stony corals. This habitat occurs in subtidal, intertidal, and supratidal zones throughout Florida's coastal waters. Hard Bottom is composed of attendant epibenthic biota on a rocky substrate composed of coquina, limestone, or relic coral, molluscan, and annelid reefs. Coquina is a limestone composed of broken shell debris. Limestone rock (many different strata) occurs as high- or low-relief outcrops of calcium carbonate.
Relic reefs are the skeletal remains of once-living reefs such as the Vermetid Reef built by worm-like gastropod mollusks, Petaloconchus. These reefs are only known to be found in shallow waters seaward of the outer islands in the Ten Thousand Islands area of southwest Florida.
Hard bottom biological communities are structured by depth and latitude and inhabited by sessile, planktonic, epifaunal, and pelagic plants and animals; infaunal organisms are present in interstitial soft bottom substrate. In the region south of Stuart on the east coast of Florida and Bay Port on the west coast, subtidal hard bottom communities are characteristically inhabited by soft corals (octocorals) and sponges. Octocoral beds have dense concentrations of sea fans, sea plumes, and sea feathers. Mobile species found in octocoral beds include flamingo tongue shell, purple shrimp, and basket starfish.
Sponge beds include the branching, vase, tube, Florida loggerhead, and sheepswool sponges. Other mobile fauna found in both the octocoral beds and the sponge beds include amphipods, isopods, burrowing shrimp, crabs, sand dollars, and many species of fish. Although the coral species found in Hard Bottom habitat are not reef-building, they do contribute to the three-dimensional nature of the areas by increasing the surface area for sessile organisms and by providing important refuges for a variety of fish and invertebrates.
Warming of as little as 1◦C can result in coral bleaching. Moderate bleaching results in stress that causes reduced growth rates and reproductive output, whereas severe bleaching results in coral death. Bleaching also appears to make corals more vulnerable to disease. Ocean acidification and temperature increases may lead to shifts from coral dominated reefs to reefs dominated by algae or sponges. Increased ocean acidity will reduce calcification and compromise skeletal structure of coral reefs.
Increased precipitation will lead to increased runoff, impacting water quality by increasing nutrients, pollutants, and turbidity. It can take years for coral reefs to recover from damage incurred by storms and increasing storm frequency will reduce the odds of recovery between disturbance events.
More information about general climate impacts to habitats in Florida.
Many reef-associated species are expected to decline because of the decline in their coral-constructed habitat. Both fish and invertebrate diversity are expected to decrease with loss of coral cover and structure. Some coral-associated species may be able to live in other habitats (e.g., rocky reefs), but others are specialized coral associates restricted to reefs.
More information about general climate impacts to species in Florida.