Samenvatting

Since the return of the grey wolf (Canis lupus) in the Netherlands in 2015, much research has been done on the ecology and distribution of the species. This has led to a dietary study using hair- and DNA-sampling of wolf scats, and preliminary analyses of DNA in wolf scats showed that DNA from non-prey, including red fox (Vulpes vulpes) is regularly present in wolf scats. A possible cause for this is an interspecific interaction between other species and wolf scats, since scats serve as olfactory cues for other individuals. However little is known about behavioral responses of other vertebrate species towards wolf scats in the Netherlands. Findings on these interactions could contribute to the knowledge of how other animals respond to wolf droppings and how possible associated contamination of DNA may take place. For this reason, a one-month pilot study was initiated in May 2023 in Hart van Drenthe and Drents-Friese Wold using camera traps, to find out more on the occurrences of behavioral responses to wolf scats from other vertebrate species. The study also hoped to found out which species show a fear or attraction towards wolf scats, and finally, the study hoped to find out if behavioral responses (such as over-marking of mesopredators) could lead to DNA-transfer on wolf scats. The initial expectations were an attraction and interactive responses including over-marking from mesopredators on wolf scats, possibly leading to DNA-contamination. Additionally, a fear towards wolf scats and increased vigilance was expected from ungulates, and it was expected that birds would be attracted to the scats to forage on invertebrates living on them Ungulates and lagomorphs showed vigilance to wolf scats 12% of the time, indicating fear towards wolf scats. Mesopredators showed interactive behavior 32% and vigilance 8,5% of the time, indicating both attraction and fear towards wolf scats. Wolves showed little response to wolf scats and birds not engaging with wolf scats, behavior which is possibly habitat-specific. Foxes over-marked on top of wolf scats rather than next to it 75% of the time, European badger (Meles meles) 27,3% and dog (Canis lupus familiaris) 50% of the time, making DNA-contamination from these species on wolf scats likely. A nation-wide study to the interspecific interactions with the wolf is therefore recommended, and any follow-up study should be done with fresh scats to gather a reliable and population-specific data set on interspecific interactions between the wolf and its nosy neighbors.