Pelagic forage fish feeding habits in the Adriatic Sea – a stomach content analysis approach

Abstract

In this study, the feeding habits of seven pelagic forage fish species inhabiting the Adriatic Sea, were evaluated by applying the stomach content analysis. Each month from June 2023 till September 2024 all biological samples were collected along the eastern Adriatic by commercial purse seiner “srdelara”. A total of 742 stomach samples were analysed. Small pelagic species such as sardine (Sardina pilchardus (Walbaum, 1792)), anchovy (Engraulis encrasicolus (Linnaeus, 1758)) and round sardinella (Sardinella aurita Valenciennes, 1847) primarily consumed copepods, while medium pelagic species including Atlantic horse mackerel (Trachurus trachurus (Linnaeus, 1758)), Mediterranean horse mackerel (Trachurus mediterraneus (Steindachner, 1868)), Atlantic chub mackerel (Scomber colias Gmelin, 1789), and bogue (Boops boops (Linnaeus, 1758)) favoured larger prey such as mysids, euphausids, and decapod larvae. Seasonal variations were observed, with copepods dominating diets during warmer months and larger prey items during the colder part of the year. Lower differences between small and medium species diets occurred in warmer months, linked to increased zooplankton availability in the investigated area. The results obtained in this study indicated potential competition among the observed pelagic species, particularly under resource-limited conditions, highlighting the necessity of adopting an ecosystem-based approach in fisheries management. Such an approach would undoubtedly ensure the sustainable exploitation of these renewable resources in the Adriatic Sea.