Wolof's knoll: A small seamount on the Mauritanian continental slope

Abstract

One of the objectives of the Maurit-1011 survey was the environmental and faunistic characterization of a small seamount of 200 m in height, discovered during the Maurit?0911 expedition, on the upper continental slope south of Nouakchott, at 17°08' 50"N and 16°46' 38.1"W. It is an isolated conical structure with small ridges, almost parallel to the edge of the continental shelf and not connected to nearby coral mounds barrier. The geomorphology of this submarine elevation, as well as the debris from a hydrothermal vents or cold seeps discovered in the rock dredge samples suggests a diapiric association because no hydrothermal benthic fauna was found. The summit of the seamount was covered with sponges belonging mainly to the family Geodiidae, and ophiuroids belonging to the suspension-feeders family Ophiotrichidae. We also found accompanying fauna comprising about 50 species, mainly consisting of molluscs and decapods. Despite its small size but taking into account the richness of the suspension-feeders community living on it, this Wolof's Seamount (so called to honour the artisanal fishermen who first discovered it) could be promoted as a marine protected area in the Mauritanian continental margin.