Macrobenthic community structure and total sediment respiration at cold hydrocarbon seeps in the northern Gulf of Mexico

Abstract

Cold seeps are areas of high biomass in the deep-sea, the impacts of these food-rich environments upon the sediment community is unknown in the Gulf of Mexico. The structure and function of benthic communities was investigated at food-rich and food-limited sites on the northern Gulf of Mexico continental slope. Cold seeps were richer in macrofauna densities and total sediment respiration, but were poorer in biomass and taxa diversity than normal slope communities. Decreased diversity is seen at most chemosynthetic communities and suggests a competition for resources. The spatial extent of these results at seeps is unknown and may be a localized, bioenhancement effect caused by seeping fluids.