Mapping the Spanish bottom fishing footprint (1996-2006) in the SEAFO area: a possible example to proceed

The criteria adopted by the SEAFO Commission for the establishment of a fishing footprint, “if an area has been fished in two consecutive years during the period 1987-2007”, is considered not a good starting point for any rigorous analysis of the historical spatial effort in the region because of losing valuable data and the difficulties on its application. Spanish data consisting in 1191 records of haul by haul (August 1996 - November 2006) were analyzed using a protocol developed by New Zealand at SPRFMO to study trawl footprints in this region. The use of 20’x20’ blocks method clearly overestimate the footprint. Thus, 10’ gridding fits better fishing footprint area. However, at any case more than one point (e.g., midpoint) has to be used to define a set/haul position. Longlining is the fishing activity more widely spread out with 144 blocks (8.79%) of which 67% “lightly fished”; and 33% “moderately fished”. However, bottom trawl tend to concentrate its activity in small areas as Valdivia Bank and the North-East of the Walvis Ridge, with 5 “heavily fished” blocks (0.31%). A general vision of current and recent past situation of fisheries in the SEAFO region was also mad