A GIS for the management of fisheries in West Africa: preliminary application to the octopus stock in Senegal

Abstract

A preliminary application of a Geographical Information System (GIS), based on a georeferenced database including data from commercial fishing and oceanographic surveys, and on geographical objects describing the physical and juridical environment, trawl operations and artisanal fishing sites, is presented. An ArcView environment is used to show spatial and temporal phenomena. Seasonal distribution charts for Octopus vulgaris and for the main associated finfish species on the Senegalese continental shelf reveal that octopuses are particularly abundant on the deep part of the continental shelf off Casamance and the Grande Côte during the cool season. Warm-season distribution seems to be more coastal. The results allow the interactions between artisanal and industrial fisheries and areas of potential conflicts to be identified. The intensity of these interactions for resource access and space allocation is highly correlated to season. The results also provide alternative explanations for fisheries management, e.g. on the degree of respect for or the relevance of the limits of regulated fishing areas and spatial fishing unit strategies according to the main seasons.