Invertebrate Megafauna in the Perdido Fold Belt Polygon, Gulf of Mexico, Mexico

Abstract

Four oceanographic campaigns were done in the Perdido Fold Belt zone of the Gulf of Mexico during 2016 and 2017 to generate baseline data on several macrodescriptors to characterize the region and establish existing biological-ecological conditions before hydrocarbon exploitation begins in the area. General megafauna invertebrate data were collected by trawling with a sled net (2.4m 2 aperture). Seven Phyla were recorded in 66 trawls in a 274,593m 2 area at depths ranging from 44 to 3609 m. Species richness was 299, abundance was 37,024org/hectare, and biomass was 305.5kg/hectare. Total ecological diversity for invertebrate megafauna in the study area as represented by the Shannon-Wiener index, was 5.35bits/ind.Megafauna in this area of the Gulf is very diverse, with the highest abundances of Phyla and species recorded nearest the coast.