It takes time to see the menu from the body: an experiment on stable isotope composition in freshwater crayfishesJ. Jussila, T. J. Ruokonen, J. Syväranta, H. Kokko, A. Vainikka, J. Makkonen and R. KortetKnowl. Manag. Aquat. Ecosyst., 416 (2015) 25DOI: https://doi.org/10.1051/kmae/2015021