Since the year 2000, the Eurasian grey wolf, Canis lupus lupus, has spread across Germany. Ines Lesniak, doctoral student at the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW), and her colleagues, have taken a closer look at the parasites of this returnee to determine whether the number and species of parasites change with an increasing wolf population. This was the case, because the number of parasite species per individual wolf increased as the wolf population expanded. Furthermore, cubs had a higher diversity of parasite species than older animals. The good news: wolf parasites do not pose a threat to human health. The results of this study were published in the scientific online journal Scientific Reports.