ABSTRACT
In many parts of the world, and particularly during the last decades, commercial (harvested or cultured) bivalves have been struck by mass mortality episodes due to climatic and/or anthropogenic stressors whose causes and consequences are not always clearly understood. Such outbreaks have resulted in various mitigating or adaptive responses from fishers or farmers, which are rarely assessed for their social and ecological outcomes. In the present chapter, a case study of shellfish farming affected by summer mass mortalities of young oysters in France from 2008 onward is developed using the I-ADApT framework. Specifically, this framework was used to assess the impacts or consequences of perturbations on the natural, social and governing systems and the subsequent individual and collective responses of the stakeholders (users, managers, state) to such events. Short-term effective responses came mainly from the industry itself rather than from the governing system. Against all scientific recommendations, the shellfish farmers decided to overinvest in hatcheries and spat (oyster seed) collection to compensate for the high mortality rates striking the cultured stocks. Market prices have increased significantly after the decline of output levels, resulting in better profitability levels for the surviving firms. This case study raises the challenge of coping with a critical issue in the particular context of an anthropic marine system dedicated to aquaculture.
