COPEPOD ASSEMBLAGES IN SURFACE WATERS OF THE WESTERN GULF-OF-MEXICO

Composition, distribution, and abundance of the pelagic copepods colle cted in surface waters of the western Gulf of Mexico during the EMOAPI cruise (May, 1993), were determined. A total of 55 species were ident ified. The most abundant were Temora turbinata, Clausocalanus furcatus , Paracalanus aculeatus, and Corycaeus speciosus; together they consti tuted more than 50% of the copepods in numbers. From cluster analysis (Bray-Curtis Index) using the 12 most abundant copepod species, four f aunistic assemblages were recognized. Their arrangement in the surveye d area followed the conditions of the coastal-oceanic gradient. Result ing assemblages were compared with previous surveys and constitute a d etailed description of faunal variations of the copepod community in t he area. The structure of the local copepod community was related to t he prevailing hydrographic conditions dominated by heavy land effluent s and by the intrusion of an oceanic front into the shelf area mainly related to the presence of an eddy derived from the Loop Current. Diff erences in copepod community structure seem to be related mainly to va riations within the coastal-oceanic gradient.