CORALES, FORMACIONES ARRECIFALES Y BLANQUEAMIENTO DE 1987 EN BAHIA PORTETE (GUAJIRA, COLOMBIA)

Abstract

In order to describe and characterize reef formation in Bahia Pórtete, a survey was conducted between June 1987 and January 1988 in wich a total of 22 stations were visited. Acropora cervicomis, Agaricia agaricites, Montastrea cavernosa, Diploria clivosa and Isophyllia sinuosa, were recorded for the first time amounting to 18 the number of scleractinian species for the bay. The principal component of the coral formations was the hydrocoral Millepora alcicornis due to its abundance and morphological diversity. Reef formations in the area are concentrated on the west and southwest side, not massive enough, however, to be considered real framework reefs. Structuraly two kinds of formations were discriminated: type 1, reef patches, and type 2, seagrass beds with dispersed colonies. Density of colonies was estimated for this latler type, ranging between 6.6 and 35.5 colonies/m2. Additionally, an extensive bleaching phenomenon was observed in October-November 1987, that affected mainly Millepora alcicornis, Pontes astreoides and Pontes pontes. At least six scleractinean species and one hydrocoral showed bleaching. In type 2 formations 25.9 % of colonies was affected. Exact causes for bleaching could not be determined but it is believed that high temperatures in those months together with normal turbid conditions in the area resulted in massive loss of simbionts zooxanthellae. Similar events were registred for most part of the Caribean sea in 1987.