After the sinking of the oil carrier ‘Prestige’, which occurred in November 2002, approximately 60,000 mt of heavy oil (type M-100) were spilled into the ocean. Immediately after the accident, a series of management measures were applied to fisheries in the area, resulting in the establishment of various closed areas. Four of the most important fleets operating in the north and north-east of the Iberian Peninsula were affected (otter trawl, pair trawl, purse seine and hand line fishing gears). These fleets exploit important fisheries resources, some of them currently beyond their biological security limits. Reductions in effort were observed in all of them, particularly in the first three months of the ban and in the north-eastern area. However, apart from the hand line fleet, this did not involve a considerable reduction in the total effort produced by each of the fleets in 2003. The pair trawlers perform two trip types, but no differences in the specific composition were observed in any of them during the three years under analysis. Five types of trawling trip were identified, but important reductions were only observed for Norwegian lobster, with the fleet targeting this species as well as hake, megrim and monkfish.