Tendências das capturas e estado de exploração de Johnnius dussumieri, Hilsa kelee, Thryssa vitrirostris, a sul do Banco de Sofala, Moçambique

Abstract

Fishing is an income-generating activity for communities; however, it also presents significant risks for investors from a profitability standpoint, as it is difficult to predict the quality and quantity of fish that a vessel may produce. Johnius dussumieri, Hilsa kelee, and Thryssa vitrirostris have been categorized as pelagic fish associated with the oceanic habitat. Their exploitation in the waters of the Mozambican Sofala Bank is highly intensive, and there is little information available regarding their stock status. Such information is essential for implementing fishery management measures based on quota systems. This study examines the annual and seasonal variations in catches and fishing effort relative to the maximum sustainable yield (MSY) of Johnius dussumieri, Hilsa kelee, and Thryssa vitrirostris, based on catch per unit of effort (CPUE) in the southern part of the Sofala Bank, Mozambique, during the period 2010–2020. To achieve the set objectives, historical data from artisanal fishing provided by the National Fisheries Research Institute (IIP) – Sofala Delegation, covering 2010 to 2020, were utilized. The analysis was conducted using an equilibrium approach with the Schaefer model. The results revealed that CPUE has been decreasing over the years. One of the environmental factors influencing catch variations is the fluctuation in water salinity, which is affected by the freshwater input from precipitation. These variations can be attributed to several factors, most notably the abundance of shrimp, fishing effort, fishing techniques, and other environmental variables.