Environments - Coral Algal Reefs

The major reef area of the Bermuda Platform is found around the shallow water platform to the north of the islands. These reefs are of several types, changing in shape and structure from the edge of the platform to the sheltered inshore basins encompassed by the islands.

There are two major reef building communities in Bermuda: (1) a coral-algal consortium and (2) an intergrowth of encrusting organisms. The coral algal reefs are by far the more extensive in range, area and relief.

The innumerable reefs that dot the north lagoon and make up the ledge flats are constructed mainly by hermatypic coral and algae. Of the 22 species found in Bermuda, those that contribute significantly to the reef mass are Diploria (2 species), Montastrea (2 species), Oculina (3 Species), Porites (2 species), Siderastrea (2 species), Isophyllia (2 species), and Favia; Acropora is conspicuously absent. The reef biota also includes the Hydrozoa Millepora, various thick shelled Molluscs, coralline algae (encrusting and delicate branching forms), gorgonian, soft coral, the entrusting pink foraminifer Homotrema, tunicates, holothurians, and a host of less abundant organisms such as ophiuroids, bryozoan and crustaceans.