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Hermatypic scleractinian corals of the southeastern Bahamas: a comparison to western Atlantic reef systems

1996; Elsevier BV; Volume: 43; Issue: 12 Linguagem: Inglês

10.1016/s0967-0653(97)84904-6

1878-6731

Mark Chiappone, Kathleen M. Sullivan, Christian Lott,

Ichthyology and Marine Biology

– A reconnaissance survey was conducted at 18 reef sites spanning 250 km’ on the windward margin of the Caicos Bank from June to August, 1991. Five main reef types were identified from aerial imagery on the eastern Caicos Bank: patch reefs, transitional reefs, high-relief spur and groove, low-relief spur and groove, and fore reef escarpment. Reef types differed in colony density and coral coverage, although most sites were dominated by Montastraea annularis (Ellis and Solander), M. cavernosa (Linnaeus), Porites astreoides Lesueur, P. porites (Pallas), Siderastrea siderea (Ellis and Solander), and Agaricia agaricites (Linnaeus). Many of these species are dominant in Caribbean reef systems. Surveys along a north to south transect on the windward margin of the Caicos Bank revealed that corals in patch reefs and spur and groove reefs decreased in colony abundance and coverage. This gradient may be related to differences in wave energy among reefs adjacent to islands in the north and the relatively exposed reefs on the southeastern margin of the bank. Overall, reefs on the eastern Caicos Bank had lower coral cover ( < 15%) than in other western Atlantic reef systems. A north to south transect along the eastern side of the bank suggests that reef distribution and composition reflects the pattern of wave energy and tidal transport from the bank to oceanic waters. Sites adjacent to islands generally had greater species richness, density, and coverage of corals. Thirty-three hermatypic scleractinian coral species were recorded among 13 reef sites on the eastern Caicos Bank. The coral assemblage observed in the Turks and Caicos is similar to coral species lists compiled from some areas in the Bahamian archipelago. Species lists from historical surveys of western Atlantic reefs were compiled for 20 locations in the biogeographic province. Similarity among 13 locations based on coral species presence-absence was high ( z 70%), indicating a relatively homogeneous faunal composition within the central Caribbean and more northerly Bahamian archipelago. Outlying sites, such as the northern Gulf of Mexico, Bermuda, Trinidad, and Brazil, had fewer species presumably due to environmental factors, such as lower temperature minima, sedimentation, and circulation patterns. RESUMEN . – Se realizo un muestreo de reconocimiento en 18 arrecifes diseminados en un area de 250 km’, localizada a barlovento del Banco Caicos, de junio a agosto de 1991. A partir de imageries de satelite, se identificaron cinco tipos principals de arrecife al este del Banco Caicos, a saber: arrecife de parche, arrecife transitional, camellon de alto relieve, camellon de bajo relieve y la pared del arrecife frontal. Los tipos de arrecifes se diferenciaron por la densidad de las colonias y el grado de cubrimiento por corales, aunque la mayoria de los sitios estuvieron dominados por Montastraea annularis (Ellis and Solander), M. cavernosa (Linnaeus), Porites porites (Pallas), P. astreoides Lesueur, Siderastrea siderea (Ellis and Solander), y Agaricia agaricites (Linnaeus). Muchas de estas especies son dominances en los sistemas arrecifales del Caribe. A 10 largo del transecto situado a barlovento del Banco Caicos, se observo una disminucion de norte a sur de la abundancia de colonias y del grado de cubrimiento por corales en arrecifes de parche y camellones. Este gradiente puede estar relacionado con diferencias existences entre la energia del oleaje de los arrecifes ubicados al norte de las islas, y aquellos relativamente expuestos en el sureste del banco. En general, los arrecifes en la parte oriental del Banco Caicos tuvieron un a cobertura coralina menor ( < 15%) que en otros sistemas arrecifales del Atlantico occidental. Un transecto norte-sur a los largo del lado oriental del banco sugiere que la distribution y composition de los arrecifes refleja el patron de energia del oleaje y el flujo de la marea desde el banco hacia las aguas oceanicas. Las localidades cercanas a las islas tuvieron generalmente una mayor riqueza de especies, densidad y cubrimiento por corales. Se registraron 33 especies de corales escleractineos hermatipicos entre las 13 estaciones arrecifales del lado oriental del Banco Caicos. La asociacion coralina observada en las islas Turks y Caicos es similar a la listas de especies compiladas de algunas areas del archipelago de las Bahamas. Se compilaron listas de especies de muestreos historicos de los arrecifes del Atlantico occidental para 20 localidades de la provincia biogeografica. En 13 localidades, la similitud-basada en la presencia-ausencia de corales fue alta (z 70%), indicando una composition