Will they survive? Sustainability status of the fishery for Tomato Hind (Cephalopholis sonnerati (Valenciennes, 1828)) in Sri Lankan waters: a length based approach

Abstract Cephalopholis sonnerati, a grouper species, is primarily targeted for the export market in Sri Lanka. Significant harvesting occurred between 2015 and 2017, driven by the Live Reef Food Fish Trade besides small-scale coastal fisheries. Nevertheless, no scientific studies have assessed the sustainability of the fishery or the status of C. sonnerati populations in Sri Lankan waters. To address this gap, we utilized length based, data-limited approaches to assess the sustainability of the fishery for C. sonnerati in east and west coastal waters in Sri Lanka. The Von Bertalanffy growth parameters were separately estimated for west and east populations: L∞ = 63.1 and 62.4 cm (TL); K = 0.26 and 0.24/year; mean M = 0.50 and 0.47/year; L50 = 36.0 and 43.5 cm (TL) respectively. Length Based Indictors (LBIs) and Fmax suggest that the fishery for C. sonnerati was operating at MSY levels. Even though, LBIs for the conservation of immature and mature individuals for both populations fell below the expected levels, indicating fishery unsustainability. The length-based spawning potential ratio (LBSPR) of the west and east coastal populations was estimated to be 24% and 13% respectively, which were below the expected reference points of LBSPR. Furthermore, the models showed size selectivity estimates at 50% and 95% were lower than the estimated sizes at L50. In conclusion, it is suggested that the C. sonnerati populations in west and east coastal waters presumably at risk of overexploitation by growth and recruitment overfishing, highlighting the need for effective management and conservation plans.