Principles for management of inshore scallop fisheries around the United Kingdom

Fisheries for scallops, particularly the great scallop Pecten maximus and to a lesser extent the queen scallop, Aequipecten opercularis, are of considerable economic importance to the United Kingdom (UK) fishing industry. Landings of great scallops have been growing steadily since the 1970s and now consistently place this fishery in the top five most valuable species in the UK. Queen scallop catches have been much more variable over the same time period. Great scallops are predominately taken using Newhaven scallop dredges while queen scallops are mostly captured with otter trawls. A very small percentage (< 5 %) of the great scallop catch is taken by hand by SCUBA divers. There are no catch limits on UK scallop fisheries and licence number restrictions are widely regarded as ineffective. Instead great scallop fisheries are mostly managed through minimum sizes, restrictions on dredge number and seasonal closures in some regions. The use of towed fishing gear (dredges and trawls) is also prohibited in a few small areas, generally for conservation purposes. There are few management measures for queen scallops. UK fisheries for great scallops appear to be stable at present, but there is considerable evidence that their productivity could be improved dramatically by better management. This is because at present the fishery has a number of negative effects on juvenile scallops and provides few spawning refuges for replenishment of stocks. The use of towed fishing gear also damages much of the habitat that is crucial for the settlement and survival of young scallops. The negative effects of towed fishing gear, particularly scallop dredges, on benthic habitats and communities are also of considerable conservation concern. In general, areas subject to high fishing pressure tend to lose structural complexity and have lower biodiversity, species richness, species abundance and rates of benthic production. Biogenic reefs / substrates are the most sensitive to disturbance, followed by sandy / gravel areas. However, sandy / gravel substrates have strong potential for recovery if protected. Shallow, sandy areas subject to high levels of natural disturbance are more resilient to fishing disturbance, but tend to support few scallops and lower diversity of benthic species in general. Scallop fisheries also have a high by-catch of mobile benthic species such as crabs, starfish and some fish species. Although the ecological significance of this bycatch is unclear it has the