1 Environment Agency, Threshelfords Business Park, Feering, Essex, CO5 9SE, UK. [email protected].
2 Institute of Zoology, Regents Park, London, NW1 4RY, UK. [email protected].
3 Technical University of Denmark, National Institute of Aquatic Resources, Vejlsoevej 39, 8600, Silkeborg, Denmark.
4 Centre for Ecology, Evolution and Environmental Changes and Faculdade de Ciências E Tecnologia, Universidade Dos Açores, Rua Mãe de Deus, 9500-321, Ponta Delgada, Azores, Portugal.
9 The Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, Suffolk, NR33 0HT, UK.
10 Department of Aquatic Resources, Institute of Freshwater Research, Swedish University of Agricultural Sciences, Stångholmsvägen 2, 178 93, Drottningholm, Sweden.
11 The Centre for Environment, Fisheries and Aquaculture Science, Pakefield Road, Lowestoft, Suffolk, NR33 0HT, UK. [email protected].