Discarding in the English north-east coast Nephrops norvegicus fishery: the role of social and environmental factors

Abstract

Abstract Nephrops norvegicus is an important target species of demersal fisheries in the North Sea. A Nephrops sorting model was combined with catch and discard samples collected on board commercial trawlers (7 vessels, 74 trawls) to determine the composition of the catch and discards in the English north-east coast Nephrops fishery. Vessels caught an estimated 1261 kg of fish and Nephrops per day of which 544 kg was subsequently discarded. Whiting accounted for 72% of the discards by weight, and 86% of the whiting caught was discarded. There was an estimated 8545 t of fish and Nephrops caught by all vessels in this fishery during the 2001–02 season (September 2001 to April 2002), of which 3682 t were discarded, equating to a discard rate of 43%. An interdisciplinary approach, integrating biological and social data, was used to determine the main driving forces behind the discarding of whiting and Nephrops in this fishery. Discard patterns varied between vessels and light intensity had a significant relationship with Nephrops discarding. Less than 5% of caught Nephrops were discarded owing to the development of a market for small sized Nephrops. Quotas and minimum landing sizes had no discernible effect on discard patterns which were most influenced by the combining influences of trawl selectivity and market forces.