Pollution of freshwater ecosystems is a global phenomenon seriously threatening ecosystem functioning and human health. Aquatic birds can play a key role as dispersal vectors of a wide range of contaminants. Many opportunistic species feed on hotspots of pollution such as landfills and urban areas and then move to natural wetlands to rest, transporting huge quantities of pollutants. Among the most important and widespread are plastics and antibiotic resistant bacteria. In this study we analysed the gut microbiome and the associated resistome of white storks Ciconia ciconia feeding on landfills of SW Spain, and quantified plastic load through the analysis of their excreta, GPS data and bird censuses. We identified three members of the order Enterobacterales (two belonging to the family Enterobacteriaceae), two Gammaproteobacteria (Pseudomonas and Psychrobacter), and several representatives of the Bacilli (Enterococcus, Streptococcus and Staphylococcus) in the gut of birds, and identified genes conferring resistance to tetracyclines, beta-lactams, and sulphonamides. We also predicted a total of 41 and 47 kg of plastic deposited in a wetland of SW Spain during the postnuptial and pre-nuptial migration. Our results highlight the role that white storks play as biological vectors of plastics and antibiotic resistances, with implications for environmental and human health.