Mediterranean marine protected areas (MPAs) are very diverse in their intrinsic, jurisdictional, management and enforcement features (e.g. Ramos Esplá & McNeill 1994; Batisse & Jeudy de Grissac 1995). They offer a wide array of situations, ranging from relatively large multiple-use marine areas (sensu Agardy 1997), with active management and strong social interactions, to small sanctuaries that are theoretically totally closed to any human activity. This variety may illustrate a good adaptation to local needs, but often results from economic and political compromises which put the ecological considerations in the background.