Understanding how obligate freshwater organisms colonize seemingly isolated ecosystems has long fascinated ecologists. While recent investigations reveal that fish eggs can survive the digestive tract of birds and successfully hatch once deposited, evidence for avian zoochory in natura are still lacking. Here, we used a multiple lines and levels of evidence approach to demonstrate plausible bird-mediated colonization of lakes by the European perch (Perca fluviatilis). We studied a set of newly-formed artificial lakes that the...