Selectivity of 130 mm Mesh Size in Deep Sea Bottom Trawl Fishery in NAFO Regulatory Area

Abstract

In February 1995 the European Community carried out .a selectivity campaign on board of a Spanish commercial trawler, using the codend cover method. The objective was to study the selectivity of 130 mm mesh size for the deep sea trawl fisheries in the NAFO Regulatory Area. One hour and four hour hauls were used and results obtained for Greenland halibut, American plaice, roughhead grenadier and theebeard rockling. For the two flatfish species the proportion of retention increase with the duration of the haul. This increase, reflected in a decrease of the corresponding selection factor, also varies with the size of fish, being greater in smaller individuals, and induces an asymmetry in the selectivity curve. For the roundfish species data were enough only to fit the four hour selectivity curves, both appearing more symmetrical than the flatfishes ones.