Compilation of data sets relevant to the identification of essential fish habitat on the Gulf of Mexico Continental Shelf and for the estimation of the effects of shrimp trawling gear on habitat

"The alteration of essential fish habitat (structural components, benthic community structure, and ecosystem level processes) by fishing activities is not well understood, yet it is generally acknowledged that fishing can influence species com position and diversity of non-target organism s and reduce habitat complexity. Little research has been conducted on fishing gear impacts in the Gulf of Mexico, and information to predict the magnitude of these effects and to determine whether habitat alterations are short or long term is generally lacking. The environmental, ecological, and physiological processes that regulate recruitment and abundance of organism s in essential fish habitat (EFH) are complex and not well understood. Thus, impacts of habitat disturbance by fishing gear are difficult to estimate. However, fishing has been shown to affect the structural components of habitat. Numerous studies outside the Gulf of Mexico indicate that mobile fishing gear reduces habitat complexity by: 1) directly removing epifauna or damaging epifauna leading to mortality, 2) smoothing sedimentary bedforms and reducing bottom roughness, and 3) removing taxa which produce structure (i.e., colonies, tubes, mounds, burrows, and pits) (Auster and Langton 1999). Overall, the recovery of habitat structure is difficult to predict as timing, duration, severity, seasonality, and frequency of impacts all interact and influence processes that lead to recovery"--Introduction, paragraph 1. by P. Sheridan and P. Caldwell. "July 2002." Also available online in PDF format. Includes bibliographical references (page 11). 2002 NMFS (National Marine Fisheries Service) SEFSC (Southeast Fisheries Science Center) Library Public Domain 1864