In the early 2010s, the French government officially launched its energy transition strategy dedicated to offshore renewable energy. Since 2011, the government has launched several calls for tender for the construction of commercial fixed offshore wind farms in the English Channel and off the Atlantic coast. In parallel, in the mid-2010s, the French State showed an interest in floating wind energy, with the planning of four pilot farms off the Atlantic and the Mediterranean coasts. Although the offshore wind energy sector is growing in Europe, floating offshore wind energy deployment is currently at an early stage. Floating offshore wind energy represents a major technological breakthrough, harnessing offshore energy resources that were as yet out of reach, but which are recognized as more abundant. In addition to strengthening France's strategic positioning among the pioneer countries in Europe for the development of increasingly mature technology, floating wind turbines present other assets: diversifying the French offshore renewable energy mix, improving an offshore sector that is, apparently, less controversial or disrupted than its bottom-fixed counterpart (in terms of cohabitation with other maritime uses and preservation of marine ecosystems). To better understand the socio-political impediments to the implementation of floating wind farms, we conducted a study of the local governance process around the implementation of one of the first floating offshore wind farms in France, in the Bay of Biscay. This study focuses on the analysis of perceptions of floating OWF impacts by decision-makers involved in the validation process of the Environmental Impact Assessment: how do these decision-makers perceive, value and relate to the marine ecosystem in the presence of a floating OWF? How do ecological factors shape decision-making, and what ecological factors are involved? The paper applies a network perspective in the analysis of the local marine social-ecological system (SES) to: identify nested social-ecological variables and key social-ecological networks influencing the licensing process in the floating OWF sector in France, 2) analyzing the power positions and the functioning of interactions through ethnographic observation of a political-administrative process, and pragmatically questioning the environmental governance of energy transition towards sustainability.