Analyse, par questionnaire, de l’interaction entre l’aquaculture offshore et la biodiversité marine dans la baie de Monastir (Tunisie)

Abstract

The aquaculture sector, in Monastir bay (Tunisia), has witnessed a turning point since 2008 with the setting up of seven offshore farms. The area has become, in fact, the first in offshore aquaculture production in Tunisia. All farms are rearing the sea bass, Dicentrarchus labrax, and sea bream, Sparus aurata. Studies of the potential side effects related to this activity are numerous and important throughout the world, though, they are scarce in Tunisia. The present, questionnaire-based, analysis aims to assess the impact of cage aquaculture offshore on coastal fishing activity, marine diversity, predator attraction and marine pollution. Seventy-eight fishermen were interviewed in December 2016 in three ports: Monastir, Sayada and Teboulba. About 77 % of them complained about the collapse of fish stocks and catches quality. As reported by 30 % of the surveyed fishers, fish and shellfish species that became more abundant, since the setting up of cages, were Mugil cephalus, Octopus vulgaris and Sardinella aurita. The attraction of sea turtles and dolphins was reported by more than 15 % of fishermen. Damage to fishing nets and depredation by dolphins was reported by 31 % of fishermen. The present preliminary work provides useful information for decision-makers towards the development of an environment-friendly offshore aquaculture strategy.