The role of benthic amphipods in Antarctic trophodynamics: a multidisciplinary study

Long-term controlled feeding experiments have been performed with four Antarctic amphipod species. For several weeks three scavenger and one herbivore species (Abyssorchomene plebs, Pseudorchomene coatsi, Waldeckia obesa and Djerboa furcipes, respectively) have been fed ad libitum with an isotopically known food. The aim of those experiments was primarily to determine the isotopic fractionation factor between animals and diet. Secondly, turnover rates of tissues have been estimated by following their isotopic ratios evolution due to the shift of the food. Comparison has been made between herbivore and scavenger species. Such experimental data are necessary to improve isotope-based trophic models.