The influence of upwelling filaments and island-induced eddies on the decapod larvae distribution in the Canaries Coastal Transition Zone

Abstract

The distribution and transport of decapod larvae were studied along a filament-eddy system located in the transition zone between the NW Africa upwelling and Canary Islands waters during the summer of 1999. Two independent filaments were developed between Cape Juby and Cape Bojador to merge at 100 km offshore during the cruise. The merged filament interacted with transient cyclonic and anticyclonic eddies shed from the island of Gran Canaria. Mesoscale oceanographic features strongly influenced the horizontal distribution of decapod larvae. Benthic larvae were mainly associated with upwelling filament structures, while oceanic larvae were related with eddies structures. In this sense, eddies acted as a mechanism of concentration, while upwelling filaments were dispersive, transporting larvae from the African neritic zone into oceanic areas and towards the Canary archipelago. This study suggests that there are clear evidences of connectivity between marine populations of African and Canaries coast