Research interests Accomplished research (1982-1992): Metabolic and hormonal adaptations to long-term fasting in birds and mammals (Physiology/Eco-physiology). Laboratoire d'Etude des Régulations Physiologiques (67 Strasbourg, France). Current research (1993 until now): Pelagic ecosystem, marine resources, and food and feeding ecology of top predators (Ecology). Centre d'Etudes Biologiques de Chizé (79 Villiers-en-Bois, France). Key words: bio-indication, cephalopods, crustaceans, diet, environmental variability, fish, food web, lipids as trophic markers, marine mammals, pelagic resources, resource partitioning, seabirds, Southern Ocean, stable isotopes, trophic segregation. My research activities focuse on the three following topics: 1. Structure and functioning of the pelagic ecosystem Determination of key pelagic species (crustaceans, cephalopods and fish) for the nutrition of predators, and quantification of biomass and energy fluxes between marine resources and predator populations. 2. Plasticity in resource acquisition of seabirds and marine mammals - Community structure To understand how predators cope with the marine environment that is variable both in space and time, and how various predator species share the marine resources within and outside the breeding period. 3. Top predators as bioindicators of marine resources Seabirds and marine mammals as biological samplers of poorly known pelagic organisms (as cephalopods and myctophid fish) to collect information on their biogeography, habitat, abundance and life cycle. 4. Top predators as sentinels of the health of the ecosystems Contaminants (heavy metals and POPs) in predators to characterize pollution in marine trophic webs and to study how seabirds cope with high mercury levels. My program is mainly devoted to seabirds (penguins, albatrosses and petrels) and marine mammals (fur seals, elephant seal), but it also includes some species of fish and squids. Most of the field work takes place in the southern Indian Ocean (Crozet, Kerguelen and Amsterdam Islands, Adélie Land), but I also worked in collaboration with foreign scientists at Bear Island (Arctic), in Tasmania, Southern New Zealand (Campbell Island), the Falkland Islands and in the Ross Sea and Svarthamaren (Antarctica). Feeding ecology of top marine predators is investigated through the use of various methods including mainly: - the conventional method of food analysis. Prey are determined from stomach samples (birds, fish, squids) and scats (fur seals); - the indirect methods of stable isotopes (13C, 15N, 34S) and lipids as trophic markers. Publications: About 320 scientific articles during the period 1981-2021. h-index: 64; ~13,000 citations (Web of Science, All databases) Editorial responsabilities: Contributing Editor (Marine Ecology Progress Series), Associate Editor (Marine Biology), member of the Editorial Advisory Board (Antarctic Science) until 2019.