Seasonal and spatial variation in the biomass and size frequency distribution of fish associated with oil and gas platforms in the northern Gulf of Mexico

Abstract

Objectives of this study were: “1) Measure and compare the species composition, biomass and size frequency distribution of fish associated with three petroleum structures. 2) Determine the effect of temporal, physical and chemical variables on species composition, biomass and size distribution of fish associated with platforms. 3) Define the spatial near field influence of each platform on the abundance of fish.”

Acoustic surveys were conducted at six platforms in the Gulf of Mexico, followed by visual surveys.

From the Results: “This research confirms the variability of fish assemblages associated with petroleum platforms and reinforces the need to sample on each side and throughout the water column to obtain an accurate estimate of fish abundance. It also demonstrates the importance of petroleum platforms to the marine environment of the northern GOM due to the high abundance of fishes found at the sites. Although some variance was observed, 10,000 to 30,000 fishes were found at a site at any one time, and since over 1,000 platforms are found in similar water depths, it is clear that these structures impact the fisheries of the region.”