1. Section for Freshwater Fisheries and Ecology, National Institute of Aquatic Resources, Technical University of Denmark Vejlsøvej 39 Silkeborg 8600 Denmark
2. Department of Fisheries and Oceans Canada Maurice Lamontagne Institute 850 route de la Mer Mont‐Joli QC G5H 3Z4 Canada
3. Department of Biology & Institute of Environmental and Interdisciplinary Sciences Carleton University 1125 Colonel By Dr. Ottawa ON K1S 5B6 Canada
4. NTNU University Museum, Norwegian University of Science and Technology Høgskoleringen 1 Trondheim 7491 Norway
5. Department of Ecology, Evolution and Marine Biology University of California Santa Barbara, California, UCSB Marine Science Institute Building 520 Santa Barbara CA 93106‐6150 U.S.A.
6. Centre for Environment, Fisheries and Aquaculture Science Pakefield Road, Lowestoft Suffolk NR33 0HT U.K.