The present study is the result of collective work on the analysis of the controversy surrounding the incidental capture of marine mammals and birds due to fishing in the Bay of Biscay. For this research project, the levers and obstacles to taking social and environmental issues into account in the political decision-making process and the management of incidental catches are studied. Among the levers, we evaluate the relevance of the principle of ecological solidarity from the environmental code in the resolution of the conflict. Consequently, this article is an opportunity to test the application of this principle and its possible consequences in the face of the problem of bycatch in the Bay of Biscay.