Specialist of fish populations in rocky areas and seagrass beds (Posidonia oceanica).My work takes place mainly in the marine protected areas (Port-Cros National Park, Marine Reserve of Scandola, Fishery reserve of Cantonment Cape Roux - Saint Raphael) and aims to understand the functioning of fish populations and the role of biodiversity in ecosystem functioning as well as the importance of habitat structure. I have developed new methods of in situ monitoring of fish populations, especially in the field of citizen science (FAST method). I regularly publish new or updated records of fish species for France or the Eastern Mediterranean (Gobiidae, Kyphosidae, Siganidae, Fistularidae, Oplegnathidae). One part of this activity is devoted to the non-indigenous species of fish spreading in the North-Western Mediterranean. In parallel, I have developed expertises to assist marine protected areas managers facing human activities (fishing, anchoring, etc). I recently carried out researchs involving Ecopath and Ecosim models (EwE) to analyze the role of the high trophic level predators in coastal ecosystems, particularly in relation to MPA management. All this work takes place in the western Mediterranean, but also in the eastern Mediterranean (Turkey in particular).