RESUMEN
Infestation by the nest-dwelling Ixodes hexagonus Leach and the exophilic Ixodes ricinus (Linnaeus) (Ixodida: Ixodidae) on the Northern white-breasted hedgehog, Erinaceus roumanicus (Erinaceomorpha: Erinaceidae), was investigated during a 4-year study in residential areas of the city of Poznan, west-central Poland. Of 341 hedgehogs, 303 (88.9%) hosted 10 061 Ixodes spp. ticks encompassing all parasitic life stages (larvae, nymphs, females). Ixodes hexagonus accounted for 73% and I. ricinus for 27% of the collected ticks. Male hedgehogs carried significantly higher tick burdens than females. Analyses of seasonal prevalence and abundance of I. hexagonus revealed relatively stable levels of infestation of all parasitic stages, with a modest summer peak in tick abundance noted only on male hosts. By contrast, I. ricinus females and nymphs peaked in spring and declined steadily thereafter in summer and autumn, whereas the less abundant larvae peaked in summer. This is the first longterm study to evaluate the seasonal dynamics of both tick species on populations of wild hedgehogs inhabiting urban residential areas.