Jérôme Pinti, Centre for Ocean Life, DTU Aqua, Denmark, Kongens Lyngby, Denmark, Thomas Kiørboe, Technical University of Denmark, National Institute for Aquatic Resources, DTU Aqua, Charlottenlund, Denmark, Tommy Norin, Centre for Ocean Life, DTU Aqua, Technical University of Denmark, Kongens Lyngby, Denmark and André W Visser, Technical University of Denmark, National Institute of Aquatic Resources, Copenhagen, Denmark