 Protecting marine biodiversity: Looking at the Mediterranean Sea through the prism of IUCN tools 
The Mediterranean Sea brings together strong economic (global transport, tourism, fishing), social (immigration) and environmental (biodiversity hotspot, and heavily impacted by climate change) issues. This small semi-enclosed sea appears as a suitable area to question two environmental marine tools : the International Union for Conservation of Nature (IUCN) Red Lists and protected areas. The aim of this study is to understand the implementation of these two tools in the marine environment, after analyzing the emergence of environmental issues in political and scientific spheres. Based on a methodology bringing together participant observation in an institution dedicated to the protection of Mediterranean island areas including their maritime component, semi-structured interviews, and documents reviews, this study proposes a reflection based on concepts and analytical frameworks developed by science studies, management sciences and geography. The goal is to analyse the construction of environmental issues by formalizing a cyclic dynamic linking scientific object and political environmental subject. Marine environmental issues are repositioned in this dynamic by studying more particularly the place of uncertainties. The aim of this study is to question the relevance of transferring two tools for biodiversity conservation (Red Lists and protected areas) from terrestrial to marine environments. Initially developed for the conservation of the terrestrial environment, these tools do not adapt as easily to the marine environment where naturalistic data are scarcer, and the uses are not fully compatible with some objectives of protected areas.