Professor and Head of Department, Goethe University Frankfurt

Professor of Aquatic Ecology, University of Duisburg-Essen

Department of Marine, Earth and Atmospheric Sciences, North Carolina State University

Dept. Biol. Sci. Old Dominion University

Forest Research Centre, Sabah Forestry Department

Aquatic Ecology, University of Duisburg-Essen

Professor at the Goethe-University Frankfurt

Macquarie University

Professor of Ecology, North-West University

Professor, Faculty of Veterinary Medicine, University of Calgary