ABSTRACT. – Despite the interest of studying animal populations at the limit of their geographical distribution, little is known about the shag (Phalacrocorax aristotelis) in the extreme southern part of its range. In this study, the diet of the Mediterranean shag subspecies (P. a. desmarestii) was studied in the Riou Archipelago (French Mediterranean coast) through the analysis of 109 regurgitation pellets during the non-breeding period from 2004 to 2007. The objectives were (i) to determine the diet of the shag in this area, and (ii) to evaluate the interaction with local fisheries. A total of 2462 pairs of otoliths was found in pellets. Six fish families (Atherinidae, Pomacentridae, Labridae, Centracanthidae, Sparidae and Serranidae) composed 92 % of the shag diet (prey number). Shags mainly fish on shallow rocky bottoms and above or in Posidonia oceanica seagrass meadows. As they mainly targeted small fishes (~10 cm TL), they did not strongly overlap with local fishing activities. Moreover, shags and fishermen do not target the same fish species, and commercial prey items represented only 11% of the total prey in shags diet.