This communication presents the results of a research carried out in the protected area of Aiguamolls de l’Empordà , in the heart of Costa Brava, Spain, where a proposal to extend the perimeter of the protected area in order to guarantee the connectivity function of the territory has created a local but severe social conflict. Our main objective is to explore public perceptions of this intervention in order to deepen in the main causes of such social rejection. The research has collected the local opinion on the problem and the perception of the socioeconomic and environmental impacts of the proposal. It is basically an analysis on the institutional performance followed by a social perception study based on a qualitative survey with local stakeholders. The results show different social positions regarding the proposed solution. Essentially, the intervention is felt as a threat to the future of several socioeconomic activities (i.e. agriculture). Moreover, mistrust on the public administration and the lack of public participation has reactivated the emergence of an old conflict.