[1] Thunen Inst Sea Fisheries, Herwigstr 31, D-27572 Bremerhaven, Germany
[2] Univ Salford, Sch Sci Engn & Environm, Manchester, England
[3] Tech Univ Denmark DTU Aqua, Natl Inst Aquat Resources, Vejlsovej 39, DK-8600 Silkeborg, Denmark
[4] Wageningen Univ & Res, Wageningen Marine Res, Haringkade 1, NL-1976 CP Ijmuiden, Netherlands
[5] Royal Belgian Inst Nat Sci, Marine Ecol & Management, Vautierstr 29, B-1000 Brussels, Belgium