1. Section of Freshwater Fisheries and Ecology, Technical University of Denmark, DTU Aqua, Silkeborg, Denmark.
2. Department of Biology, Ball State University, Muncie, IN 47306, USA.
3. National Institute of Water and Atmospheric Research, Auckland, New Zealand.
4. Centre for Environment, Fisheries & Aquaculture Science, Lowestoft Laboratory, Pakefield Road, Lowestoft NR33 0HT, UK.
5. School of Environmental Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK.
6. Section for Monitoring and Data, Technical University of Denmark, National Institute of Aquatic Resources, Kgs. Lyngby 2800, Denmark.