Dead birds for this study were collected in beaches by Itsas Enara Ornitologi Elkartea and anonymous volunteers, as well as kindly provided by the wildlife recovery centers of Cantabria, Bizkaia and Gipuzkoa, the beach cleaning services dependent on the Bizkaia and Gipuzkoa Provincial Councils and the city councils of Getxo, Zarautz and Donostia, and the Wildlife Care Center "Centre de Sauvegarde du Marais aux Oiseaux" (Oléron Island). Our gratitude to Urdaibai Bird Center and Plentziako Itsas Estazioa (UPV/EHU) for their collaboration. We are very grateful to G.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.