Diversity and stability of demersal species assemblages in the Gulf of Guinea

Abstract

The structure of demersal fish assemblages on the continental shelf and upper continental slope of the Gulf of Guinea is described. Community structure is determined primarily by depth and type of sediment on the seabed. Changes in the composition of the identified species assemblages over a 25-year period are examined. The dynamics of the assemblages are influenced by physico-chemical parameters of the water masses, mainly temperature, salinity and dissolved oxygen, which are periodically modified by the seasonal coastal upwelling that occurs in the western Gulf of Guinea. Increased irresponsible fishing operations (like the use of explosives) that lead to habitat alteration and other anthropogenic activities like oil and gas exploration which have the potential to cause environmental changes pose a threat to biodiversity in continental shelf waters of the Gulf of Guinea. industrial trawling in coastal waters and environmental forcing conjointly influenced the changes in the composition and relative importance of species in the assemblages.