Deliberative governance is gaining increasing attention in the management of natural resources with conflicting stakes. Although disputed knowledge is known to affect deliberation, the role of perceptions is understudied. Based on a case study in the Dutch Wadden Sea, a marine protected area, we examine the social representations of shellfish fisheries and marine nature of stakeholders within one deliberative governance arrangement, the Mussel Covenant. Our results show that within this covenant there are two opposing social representations of marine nature which both are not in line with the agreed objectives. Instead, governmental policies still form the guidelines to covenant decisions. We conclude that diverging representations and state-influence decrease deliberation. Therefore, we argue that deliberative governance is not possible without explicitly considering the different cognitive, normative and expressive meanings attached to the marine area or issue at stake. To achieve deliberation, values of stakeholders should explicitly be acknowledged and discussed, and state-influence should be kept to a minimum.