José Luis CortDoctor in Biology. Since 1973 he has been a researcher at the Spanish Institute of Oceanography (IEO). He has worked in the biology and dynamics of the populations of small and large pelagic fish of the Atlantic Ocean, and tropical tunas of the Indian Ocean. He chaired the scientific committee of the ICCAT (SCRS); worked in FAO Fisheries Department; and was Director of the Santander Coastal Centre of IEO. He has published articles and documentaries on biology, fisheries and population dynamics of exploited species, mainly tuna. Pablo Abaunza Doctor in Biology. Since 1990 he has been a researcher at the Spanish Institute of Oceanography (IEO), working on fishery biology of pelagic fishes. He is an expert member of several Working Groups on fish stock assessment mainly in ICES. He has worked in different positions of responsibility as Director of the Santander Coastal Centre of IEO, head of the Fisheries Department at IEO and recentlyas Deputy Director of IEO. He is co-author of several publications in specialized journals.