Disentangling the dynamic of the Moored Fish-Aggregating Devices (MFADs) fleet in Guadeloupe using a stock-flow analysis

Abstract

Fish-aggregating devices (FADs) have been used in centuries to attract fish and facilitate their captures. Drifting FADs developed at a large and industrial scale, but moored fish-aggregating devices (MFADs) are mostly used by artisanal fishers and often implemented to shift the pressure away from depleted coastal fish stocks and toward large migratory pelagic fish populations. Indeed, as pelagic fish aggregate around the devices, MFADs allow small-scale fishers to access this resource and improve their income. If there are many studies on the development of MFADs, the underlying assumption that the development of the MFAD fishery leads to the redeployment of the coastal fleet toward large pelagic species remains unproven. In the French archipelago of Guadeloupe, Lesser Antilles (FAO area 31), an important small-scale MFADs fleet targeting dolphinfish and tuna species developed since the end of the 80s. Available data on vessels, fishers and fishing effort permitted to develop a stock-flow framework and to analyse allocation of fishing effort between coastal and MFADs fisheries over the 2008–2019 period as well as the fleet and sub-fleet dynamics. The framework showed that the redeployment of fishing effort towards pelagic species thanks to MFADs was not straight forward. Pelagic vessels were more likely to become coastal than the opposite, and there was no influence of MFADs on the likelihood of pelagic vessels to quit their coastal activity. Instead, vessels fishing both on MFADs and coastal stocks were the dominant sub-fleet in the pelagic fleet in 2019. Nevertheless, pelagic vessels fished less and less on coastal stocks during the period, which was correlated with an increased use of MFAD. It also showed that the MFAD fishery remained more attractive for younger fishers but, as for the coastal fishery, MFADs failed to attract enough newcomers to compensate the outflows of ageing fishers as working conditions and barriers to enter the fishery remain key issues.