Small-scale fisheries in Istrian waters (northern Adriatic): preliminary results on catch analysis and presence of thermophilic species

Small-scale gillnet fisheries in northern Adriatic have latterly shown certain alterations, mainly related to more frequent occurrence of thermophilic species due to ongoing climate changes. This research presents data on gillnet catch in Istrian waters (Raša and Medulin Bay) in order to show the ratio of thermophilic fish species in the total catch. Net deployment was performed twice a month, from October 2020 to January 2021. A total of 29 fish species were recorded, five of which are categorized as thermophilic: leerfish (Lichia amia), pompano (Trachinotus ovatus), greater amberjack (Seriola dumerili), Mediterranean barracuda (Sphyraena sphyraena) and bluefish (Pomatomus saltatrix). This category was represented with 4.68% of the weight in the total catch. L. amia was the most represented thermophilic species with 70.23% of the total catch weight of thermophilic species. Among native species, bullet tuna (Auxis rochei) was the most represented (49.78%), followed by the gilthead sea bream, Sparus aurata (30.17%). Results have shown significant presence of thermophilic fish species in the gillnet catch in Istrian waters during the main fishing season. Although that could have significant implications in terms of conservation, management and sustainable use of the living resources, seasonal exploitation of thermophilic species could be considered as an opportunity for local fishermen.