Sigrun Jonasdottir, DTU National Institute for Aquatic Resources, Copenhagen, Denmark, Richard Broughton, University of Stirling, Institute of Aquaculture, Stirling, United Kingdom, Ceelin A. Andersen, Technical University of Denmark, DTU Aqua, Kgs Lyngby, Denmark, Josephine Bøgeskov Grønning, University of Copenhagen, Department of Biology, København K, Denmark and Andre W Visser, Technical University of Denmark, National Institute of Aquatic Resources, Copenhagen, Denmark