Diversity, occurrence and status of sharks in the Gulf of Hammamet (Central Mediterranean Sea)

This study investigates the biodiversity and status of sharks in the General Fisheries Commission for the Mediterranean (GFCM) Geographical subareas 13, the Gulf of Hammamet (Tunisia). It provides insights into shark diversity, abundance, seasonal occurrence and the impact of fisheries on their population based on inspection of fishery landings through 2020–2023. A total of 23 shark species belonging to 11 families were recorded, with over 74% classified as threatened according to the International Union for Conservation of Nature (IUCN) Red List. Analyses found that shark occurrence varied across fishing gears, with trawlers being the most impactful in terms of species. Pelagic and bottom longlines also contributed significantly to bycatch. Gillnets and trammel nets, while less impactful, still caught several vulnerable species. Seasonal variation in shark occurrence was noted, with higher landing observed in winter and autumn. The analysis revealed a strong association between shark families and fishing gear types, emphasizing selective bycatch patterns. The findings underscore the need for targeted conservation measures to reduce bycatch and protect the most vulnerable shark species in the Gulf of Hammamet.