Offshore petroleum platforms: functional significance for larval fish across longitudinal and latitudinal gradients

Abstract

This was a baseline ecological ichthyoplankton study conducted at two platforms east of the Mississippi River Delta. Using light traps and passive plankton nets larval and juvenile fish were over two nights, twice monthly, from May–September 1999. From the Executive Summary: “Patterns of larval and juvenile fish abundance and diversity were primarily influenced by across-shelf gradients of increasing water depth…The waters within platforms had higher abundances and diversity of postlarval and juvenile fishes than waters immediately down-current of the platform….Most of the reef taxa were collected during months when surface water temperatures were at their highest, i.e., June–August.” In addition, the study noted that there were strong differences in the numbers and developmental stages collected between new and full moons. Spawning may have occurred at the platforms for a number of reef species.