This study, conducted in western France from 2018 to 2021, aimed to examine the environmental disruption risks faced by the European Kingfisher, a species of conservation concern in Europe. We focused on examining the risks associated with habitat reduction, as well as the potential exposure of the species to trace elements and organic pollutants, and the effects of these pollutions on the health of individuals. Through a GPS tracking program, our results highlight the potential importance of wetlands with reduced surface areas and shallow water for the species. Furthermore, by analysing mercury and pesticide concentrations respectively in feathers and in blood samples, we also observed significant contamination of these pollutants in birds' tissues, leading to various negative health effects. Our study highlights: i) the necessity for conservation and ecological restoration policies dedicated to small wetlands to mitigate the potential detrimental effects of global changes on the conservation status of the species, and ii) the significance of apex predators, like the European Kingfisher, as keystone species, in assessing the risks of wetland contamination by trace elements or organic pollutants.