Status and trends of key prey species for the Mediterranean Monk Seal in the Eastern Adriatic Sea

The Mediterranean monk seal (Monachus monachus) is sporadically reappearing in the eastern Adriatic, but the capacity of this region to support transient individuals or future recolonisation remains poorly understood from a prey-resource perspective. We assessed the status and multi-year trends of key prey taxa known to constitute important components of monk seal diets by integrating three complementary indicators: fishery-independent biomass indices from the MEDITS trawl survey (2002-2025), fishery-dependent landings per unit effort from small-scale coastal fisheries (SSF LPUE) monitored under the EU DCF (2012-2025), and official national landing statistics (2012-2024). Species-specific trend signals were standardised and combined using a reliability-weighted traffic-light framework to classify relative prey availability as improving (Green), stable and/or inconsistent (Yellow) or declining (Red). Among 12 evaluated prey species, 6 were classified as stable or inconsistent, 4 as improving and 2 as declining. Improving classifications were driven mainly by positive MEDITS trends for Pagellus erythrinus, Pagellus bogaraveo and Mullus barbatus, and by concordant positive signals for Scorpaena scrofa. Declining classifications indicated consistent negative trends for Conger conger, and mixed but overall negative evidence for Sepia officinalis, driven primarily by fishery-independent and landings trends. Overall, the eastern Adriatic prey base appears heterogeneous rather than uniformly depleted, with improving signals restricted to a few demersal fishes and declining signals concentrated in selected high-value prey. These findings suggest that prey availability is unlikely to represent a basin-wide barrier to monk seal recolonisation, but may impose local constraints where declining prey resources overlap with intense coastal fisheries. The proposed framework identifies priority taxa and nearshore data gaps for targeted monitoring and provides a basis for more spatially explicit assessments of monk seal habitat suitability in the Adriatic.