Zonation of Dominant Fouling  Organisms on northern Gulf of Mexico Petroleum Platform

Abstract

In a study of the fouling communities of petroleum platforms near the Louisiana coast, scraped samples were collected by divers at depths from 1 to 30 m. The main habitat-forming species were barnacles and pelecypods, which accounted for over 99% of the drained weight of the samples. Other abundant forms included ophiuroids, actiniarian and zoanthid anemones, caprellid and gammaridian amphipods, hydroids, bryozoans, tunicates, and clionid sponges. Although the fauna of both nearshore and offshore platforms included many cosmopolitan taxa, a number of tropical species more commonly found on coral reefs were collected on offshore platforms. Algal abundance was higher near the surface, especially at the nearshore platforms, and was higher off shore than near shore at all depths. There was no evidence that a produced water discharge on one of the platforms had any significant effect on community composition a few meters away from the point of discharge, although it was not possible to determine the chemical content of the discharge.