Northern Ireland Scallop Larval Dispersal Background Study

Summary

he Agri-Food and Biosciences Institute (AFBI), Seafish and the Northern Ireland (NI) Scallop Association have recently completed a report investigating the optimal areas for scallop reseeding in the Irish Sea. This work was commissioned due to an increase in exploitation of scallops around the NI coastline and a desire by industry to be proactive in enhancing long-term sustainability of stocks. Sites selected through industry engagement as proposed reseeding sites were examined by AFBI scientists to ensure that they met the characteristics required for successful settlement of scallops. Seabed habitat maps were combined to provide information for the full sea area under consideration. Scallop catches from the annual AFBI scallop survey were mapped with the full habitat map to determine the areas where scallops were present and identify the underlying habitat type. This allowed a map to be created which showed the suitable habitat for adult scallops within NI waters. All of the proposed reseeding sites fell within areas of suitable habitat. To examine further characteristics of the proposed sites, a combination of measured and modelled data was used. Salinity, food availability, bed stress (natural physical disturbance of the seabed by wave action and/or tidal currents), particulate inorganic matter, suspended particulate matter, abundance of predators, spawning season, larval dispersal and hydrodynamic models were all considered. The above information was presented to the project steering group, and using the data provided, the steering group selected the most suitable sites for reseeding from the original 13 proposed sites. Three reseeding sites (Whitehead, Drumfad Bay and South Bay) have initially been proposed, with a fourth, Roaring Rock, having potential for any future reseeding plans. The NI Scallop Association will now present the results of this work to DAERA to ask for regulation to assist in the protection of these new areas through a ban on mobile fishing gear.

Author

• Agri Food,
• Biosciences Institute

Publication date

01 March 2016