Sometimes, it may be hard to differentiate tracks of the wolf and large domestic dog. Usually wolf footprints are bigger than those of dogs. Footprints left by wolves on a thin snow cover or loose ground are 8–13 cm long and 6–9 cm wide, whereas in the conditions of a loose snow cover these dimensions may be slightly higher. Prints of wolf digital pads are symmetric and oval, whereas in dogs they are frequently wider in rear part than in the front part. Male wolf has wider footprints than those of female wolf. Ratio between length and width comprises about 1.3 in footprints of male wolves, and approximately 1.5 in those of female wolves. In wolf footprints all digital pads look more massive than those of dogs in relation to the interdigital pad, even of large ones, and the two central digital pads in wolf footprints are mostly placed in front of the lateral digital pads. However, in a big male wolf the later feature is not pronounced, and this may be used for rough distinguishing of males and females among adult wolves by their fore footprints. The central digital pads are also placed tighter to each other in wolf footprints than those of stray dogs.
However, these observations are not totally reliable. Nowadays, some big dogs have big paws and rather massive digital pads like those of wolves.
Therefore, the two other below-following distinguishing features of wolf and dog tracks are crucial to make a decision to which species (wolf or dog) tracks belong.
These features originated from much trained paws of wolf as a hard walker as well the species energetically economizing walking pattern. In comparison with dog, wolf paw facing with the same substratum leaves more symmetric print of a rather strong foot. In the case of much weaker paw of dogs their footprints consist of pads that slightly distorted and slipped in different sides as well as dog’s claw marks printed sideward often, and, so, dog’s footprints look more asymmetric. Concerning wolf track trail, it is evidently more regular; stride of a wolf trail is markedly longer (60–70 cm versus 30–40 cm in dogs). Also, double footprints (superposed or in twos) of wolves are located strongly at a straight line for the most of trotting track trails. It is energetically economizing walking pattern. Dogs, while trotting, usually do not target by the hind paw in the fore footprint, and therefore their track trails consist of wavy footprint sequence with the markedly shorter stride.
Zoology by Vadim Sidorovich 