Unusual formations in the B. R. Chinchorro Bank: Miniature atolls

Abstract

There are unique reef patches in the Biosphere Reserve Banco Chinchorro reef lagoon that have an unusual formation. They appear to be miniature atolls. These formations are at a depth of 2–6 m, and present flourishing coral growth, whereas a few meters away others are strongly decayed. To define the cause of this phenomenon, an analysis of three of these formations was carried out to try to relate the structure of the corals that make up these formations to environmental factors. We recorded in tidal cycles, 12 environmental parameters, and micronutrients. Despite their closeness, two patches show high biodiversity, whereas the third shows low diversity. These results show notable differences between the three patches resulting from position on the reef (leeward and windward), in addition, these patterns relate to the undercurrent of possible relict water that drains from the lagoon microsystem of the main island of the reef, Cayo Centro, toward the miniature atolls.