U.S. Department of the Interior Minerals Management Service Gulf of Mexico OCS Region Technical Announcement

Stability and Change in Gulf of Mexico Chemosynthetic Communities
Volume I: Executive Summary
Volume II: Final Report

OCS Study MMS 2002-035 & MMS 2002-036

The Minerals Management Service (MMS), Gulf of Mexico OCS Region, announces the availability of a new study report, Stability and Change in Gulf of Mexico Chemosynthetic Communities, Volume I: Executive Summary and Volume II: Final Report.

This report provides information on the scientific results from the program of the same name, an MMS-funded survey of natural hydrocarbon/sulfide seeps supporting chemosynthetic communities in the northern Gulf of Mexico. The investigators represented the Geochemical and Environmental Research Group at the Texas A&M University, with additional ones from seven other academic institutions and one consulting company. This study, a follow-on investigation of MMS’s "Chemosynthetic Ecosystems Study" (1995), continued investigations of selected communities over the upper continental slope from 500-700 m deep (about 60-80 nmi offshore), primarily in the MMS Central Planning Area. Here, there has been a remarkable acceleration of oil and gas activity.

Several sites were chosen for additional detailed in situ study with manned Johnson-Sea-Link submersibles based on their respective geological, geochemical, and biological characteristics. Repeat submersible surveys and growth experiments were conducted. Photomosaics were made for the detection of community structure and determination of changes with time. Additional surface geophysical cruises were made in selected areas. This study provides important information on community ecology and structure; physical, electrochemical, and geochemical characterization of seep habitats; trophic dynamics; and the biogeochemistry and stability of these ecosystems. These findings have major implications for the management of the MMS oil and gas program on the northern Gulf of Mexico continental slope and the protection of these remarkable animals.

This report is available only in compact disc format. The discs are available from the Minerals Management Service, Gulf of Mexico OCS Region, at a charge of $20.00 by referencing OCS Study MMS 2002-035 and MMS 2002-036. You will be able to obtain this report also from the National Technical Information Service in the near future. Here are the addresses. You may also inspect copies at selected Federal Depository Libraries.