Fig. 1

Map of southern Scandinavia with the 50 sample sites from 2016 depicted (blue dots). At each site, a minimum of 600 tick nymphs were collected. The red ellipse marks the area where I. persulcatus was recorded in 2015 by Jaenson et al. [11]. The blue ellipses are where D. reticulatus/B. canis was found associated with dogs [24, 25], the magenta ellipse is where D. reticulatus was found on birds [23] and the green ellipses is where D. reticulatus has been found in nature [25]