Historical trends and current status of the European eel, Anguilla anguilla (Linnaeus, 1758) fishery in the Neretva estuary (eastern Adriatic, Croatia)

The European eel, Anguilla anguilla was the most important fishery resource in European estuaries for centuries. In more recent times, most local populations throughout the species' range have collapsed for various reasons. This article deals with the historical records and current status in the Neretva estuary (Croatia), the most important eel fishing area on the eastern Adriatic coast. The historical records were analysed by reviewing various available databases, including scientific articles and professional literature. Additional descriptions were obtained using local ecological knowledge and interviews with various stakeholders. The comparative analysis shows that the historical silver eel catch (1930-1940) under pristine habitat conditions should be estimated at 100 tons, officially recognized and additionally estimated. The decline in silver eel catches began between 1960 and 1970 and was related to the massive reclamation of important eel lagoons and wetlands for agriculture and port areas, when officially recognized silver eel catches at state stations averaged 45 tons per year. Recent scientific articles and reports as well as a survey of professional and recreational fishermen show that the annual catch in the period 2020-2022 is only 2 tons. The main reasons for this recent dramatic decline in eel fisheries and biological status in the Neretva estuary after 2015 are: a significant increase in recreational fishing, the establishment of invasive predatory fish and crab species, and the strong development of local tourism demand. The results of this study indicate that the local eel population is likely to be threatened with extinction in the near future unless various measures are developed and applied to protect it, including the restriction of fishing and better market control, habitat restoration and the control of invasive and competing species.