Hey, That's My Fish – Overlap in Prey Composition between European Shag and Local Fisheries in Portugal

• DOI: 10.5253/arde.v109i1.a10
• Publication Date: 2021-03-23T04:09:13Z
• Authors: Tânia Nascimento; Nuno Oliveira; António Luís
• Keywords: Diplodus; Sparidae; Overfishing; Gadidae; Forage fish

The European Shag Phalacrocorax aristotelis is a threatened seabird species in Portugal. Knowledge about this population limited, and currently there no information dietary needs threats posed by fisheries. We studied the diet composition of Shags Berlengas archipelago, largest breeding colony country, through analysis 124 regurgitated pellets, estimated trophic overlap with local fisheries, during winter seasons 2016–2017. A total 32 fish were identified their diet, while major prey consisted sand eels (Ammodytidae) from Labridae, Gadidae Sparidae families. Diet varied seasonally was more specialized season, comprising 70% all consumed 45% biomass. During winter, consumption heavier predatory increased, particularly 17 also targeted commercial same size range, highlighting potential for resource competition. Fish that contributed most to Pouting Trisopterus luscus, White Seabream Diplodus sargus, Common Two-banded vulgaris, Bogue Boops boops Black Spondyliosoma cantharus. Among different types fishery, pronounced polyvalent gear (longlines gillnets), especially than purse seine trawling. Competition between fisheries may represent an additional pressure on foraging Shags, as well increasing conflict fishing activity.