1. Department of Environmental Systems Science ETH Zurich Schmelzbergstrasse 9 Zurich CH‐8092 Switzerland
2. Department Fish Ecology & Evolution Swiss Federal Institute of Aquatic Science and Technology (Eawag) Seestrasse 79 Kastanienbaum CH‐6047 Switzerland
3. Departamento de Física y Matemática Aplicada, Facultad de Ciencias Universidad de Navarra Irunlarrea 1 Pamplona 31008 Spain
4. Departments of Chemistry and Geography University of Zurich Winterthurerstrasse 190 Zurich CH‐8057 Switzerland
5. Department of Civil and Environmental Engineering Massachusetts Institute of Technology 77 Massachusetts Av. Cambridge 02139 MA USA
6. Institute of Ecology and Evolution University of Bern Baltzerstrasse 6 Bern CH‐3012 Switzerland