Abstract
Ecological monitoring allows to collect data and to gain knowledge on species or ecosystems. Thus, ecological monitoring is the basis on which biodiversity conservation is organized. Nowadays, the spatial scales of ecological monitoring and conservation issues diversify, as well as the increased complexity of institutional dynamics related to the collection of ecological data. In the French Mediterranean, a network of thirty Marine Protected Areas (MPA) is operating along the coastline. These MPA collect ecological data and work for the protection of marine biodiversity, each at its own scale and with its own means. For many issues related to the protection of marine biodiversity, the relevant ecological scale is that of the Mediterranean coastline embracing the entire MPA network around the same ecological context. This is the case for mobile species such as marine mammals.In this context, acquiring ecological knowledge at large spatial scales from data collected by a multitude of actors raises two major issues. First, an operational and policy challenge that consists in involving and coordinating institutions and stakeholders that collect ecological data. Second, a methodological challenge that lies in the ability to propose statistical tools that can produce robust ecological indicators from several monitoring protocols. During this thesis, I wanted to jointly study both of these two issues, operational and methodological, by setting up an interdisciplinary approach mobilizing social sciences and statistical ecology. The analysis is focused on the ecological monitoring of bottlenose dolphins (*Tursiops truncatus*) in the French Mediterranean Sea.By conducting semi-directive interviews with MPA managers in the French Mediterranean, I studied the place of ecological data in the functioning of MPA and in the working life of the MPA managers. The interviews and the collaboration with biodiversity managers also allowed to identify methodological requirements to support the ecological monitoring of bottlenose dolphins at the scale of the French Mediterranean MPA network. Thus, I developed integrated modeling tools allowing the joint analysis of multiple datasets to estimate the distribution, abundance and density of bottlenose dolphins at the scale of the French Mediterranean Sea.My work will have allowed i) to propose statistical tools relevant to the current context of the ecological monitoring of bottlenose dolphins in the French Mediterranean Sea, and ii) to highlight and describe the operational and political issues of coordinating ecological monitoring between the different MPA of the French Mediterranean Sea. Overall, my thesis is an illustration of the relevancy of the dialogue between social sciences and statistical ecology to produce ecologically effective and socially relevant conservation tools.