Abundance and Associations of Epibenthic Crustacea in the Western Gulf of Mexico

Abstract

Samples of epibenthic invertebrates collected by trawling in the nortwestern Gulf of Mexico were analyzed for species identification and abundance. Crustacean species were far more common and abundant than the echinoderms and mollusks which were omitted from the statistical analysis. Crustacean species diversities of these samples range from 0.84 to 3.17. The twelve most common species were selected from a principal components analysis. Log-transformed species abundances were used to compute a correlation matrix and principal component scores. Three canonical variables explained 71% of the original variance in species abundances. Species strongly correlated with these factors are I: Callinectes similis, Trachypenaeus similis, Sicyonia dorsalis, and Squilla empusa; II: Squilla neglecta and Penaeus duorarum; III: Hepatus epheliticus and Portunus gibbesii. Variation in substrate composition may be related to the spatial distribution of these species associations.