A novel approach in regional tuna fisheries management using low resolution satellite data: A case study for the Gulf of Guinea

The tuna fisheries in the Gulf of Guinea provides huge economic benefits through fish trade and food security. The region, an important spawning site and migratory path for three dominant tuna species i.e. Skipjack (Katsuwonus pelamis), Yellowfin (Thunnus albacares) and Bigeye (Thunnus obesus), has high incidence of illegal fishing practices, in addition to poor surveillance and monitoring of fisheries resources. Adopting conservation methods for effective management of the tuna fisheries requires an understanding of their thermal preference, foraging behaviour and migratory patterns. Using tuna catch data from 2004 to 2006 in the eastern equatorial Atlantic we have described the spatial distribution of tuna catch and thermal range associated with these distribution from low resolution remotely sensed sea surface temperature data. Tuna in the equatorial Atlantic are concentrated at the major upwelling centers off the coast of Ghana and equatorial Atlantic at surface temperatures of 23 to 28°C.