1. Institute of Marine Research , Nordnesgaten 50, 5005 Bergen , Norway
2. Fisheries and Oceans Canada, Maurice Lamontagne Institute , 850 Rte de la Mer, Mont-Joli, QC G5H 3Z4 , Canada
3. College of Fisheries and Ocean Sciences, University of Alaska Fairbanks , PO Box 757220, Fairbanks, AK 99775 , USA
4. Jørstad Marin AS , Postbox 1870, Nordnes, NO-5817 Bergen , Norway
5. Institute of Marine Research , P.O Box 6606, Stakkevollan, NO-9296 Tromsø , Norway