The vulnerability of shellfish farmers to HAB events: An optimal matching analysis of closure decrees

Harmful Algal Blooms (HAB) events may have serious economic consequences for shellfish farmers. When toxic algae blooms threaten human health, public authorities decide to shut down the farming business a while, i.e. ranging from few days several weeks or months, according severity of risks. The impact closures being temporally and spatially distributed, farmers can avoid risky zones develop adaptive strategies mitigate therefore reduce significantly their sensitivity HABs. A sequential approach by optimal matching analysis is applied an original data set area closure decrees between April 2004 December 2018 in Southern Brittany Pays de la Loire (France) build typology 79 aquaculture affected various HAB microbiological hazards (ASP, DSP, Norovirus, E. Coli, oil spills). hypothesis that degree exposure hazard assessed zonal not be correlated level revealed results industry which avoidance strategies.