1. Centre for Environment, Fisheries and Aquaculture Science (Cefas) , Lowestoft NR33 0HT , UK
2. AZTI, Sustainable Fisheries Management, Basque Research and Technology Alliance (BRTA) , Herrera Kaia, Portualdea z/g, 20110 Pasaia, Gipuzkoa , Spain
3. Fisheries Ecosystems Advisory Services, Marine Institute , Galway H91 R673 , Ireland
4. Institute of Marine Research , PO Box 1870 Nordnes, N-5817 Bergen , Norway
5. Freshwater and Marine Fisheries, AFBI , Belfast BT9 5PX , UK