Domestic Dog Scent Marks Trigger a Behavioural Response in Wild Wolves

Abstract

The European grey wolf (Canis lupus) and domestic dog (Canis lupus familiaris) share not only a common origin but also many similarities in behaviour. Due to the introduction of legal protection, wolves have recolonised large parts of Europe. They are increasingly inhabiting human-dominated landscapes, leading to a growing potential for interactions between wolves and domestic dogs. However, these interactions between wolves and dogs are still poorly understood. Scent marking is one of the main forms of communication in canids and is crucial for marking territories, synchronising reproduction, establishing hierarchies within groups, and forming new breeding pairs. We hypothesised that the presence of domestic dog scent markings in wolf territories may induce a behavioural response and therefore interfere with wolf behaviour. To test this, we experimentally scent-marked objects within known wolf home ranges in Kampinos National Park, Poland, to simulate the presence of "unknown dogs" (dog urine from outside the area) and water as a control. To test whether and how wolves' behavioural response to the scents of domestic dogs and wolves differs, we additionally left scent marks of "unknown wolves" (wolf urine from outside the area). Using camera traps, we studied the behavioural responses of local wolf families exposed simultaneously to all three scent stimuli. Juveniles spent significantly more time sniffing wolf scent (37.1 ± 8.9 s) than dog scent (7.1 ± 3.4 s), while breeding pairs displayed more diverse marking behaviours, including overmarking and ground scratching, particularly in response to wolf scent. Wolves spent a longer time responding to wolf scent marks than to dog scent marks, indicating they may distinguish between them, but inexperienced juveniles spent much more time exploring dog scent marks than adults. Our results indicate that domestic dog scent marks trigger a behavioural response in wild wolves. This suggests that the increasing occurrence of dogs inside wolf territories could affect and potentially disturb the scent-marking behaviour of wolves.

Keywords: chemical communication; conservation; intraspecific interactions; territory defence.

FIGURE 1

(A) Study area, KNP. (B) Distribution of research areas, scent markings, and locations where wolves were recorded.

FIGURE 2

(A) Time spent reacting (average seconds, ± SE) to different stimuli (urine of a unknown wolf, urine of unknown dog, water) by breeding pair (left) and juveniles (right) in KNP. Asterisks indicate levels of statistical significance: *p < 0.05, **p < 0.01, *** p < 0.001. “wolf” means unknown wolf, “dog” means unknown dog. (B) Time spent reacting (average seconds, ± SE) to different stimuli (urine of unknown wolf, unknown dog, water) by a breeding female (left), a breeding male (center), and a juvenile (right) in KPN. Asterisks indicate levels of statistical significance: *p < 0.05, **p < 0.01, *** p < 0.001. “wolf” means unknown wolf, “dog” means unknown dog.

FIGURE 3

Schematic representation of the spatial layout of the experimental plots, illustrating the placement of scent stimuli (1 = dog urine, 2 = wolf urine, 3 = water) and the positioning of the camera trap. All stimuli were placed at approximately 0.5 m height on natural objects (e.g., trees), with a minimum of 1 m spacing between them to avoid cross‐contamination. The blue polygon indicates the field of view of the camera trap positioned at approximately 8–10 m distance from the stimuli. The placement of each scent stimulus at natural objects was fully randomised using a number generator.

FIGURE 4

A, B, C Identification of sex in wild wolves based on physical and behavioural characteristics captured by camera traps in Kampinos National Park (A–C).