A wolf’s sense of smell is critical and useful in many ways. Of course, wolves use their nose to hunt. But they also use their nose to identify individuals and species and to determine age, gender, diet, social rank, emotional state, and breeding condition of other wolves, according to Fred Harrington and Cheryl Asa in Wolves: Behavior, Ecology, and Conservation. “To have a wolf’s nose for only one day would surely reveal a whole new world,” they add.
To estimate the strength of a wolf’s sense of smell, the authors compare wolves with dogs, a much more studied animal. They assume that a wolf’s sense of smell is at least as strong as that of a dog. And dogs, they say, “are a hundred to millions of times more sensitive than humans in perceiving odors.”
Odors, it turns out, are honest communication that can’t be faked, since a wolf has little control over most odors it leaves behind. Those revealing scents are also much longer lasting communication than howling, the topic of Part One in this three-part series on how wolves communicate.
Harrington and Asa list a surprisingly large number of sources from which wolves produce scents:
Urine: Only dominant male and female wolves mark with urine, depositing only drops each time they mark. Dominant wolves raise their leg when urinating; the height of the urine may send a message about the stature of the animal leaving it. Males mark more often than females. Wolves mark with urine frequently along the edges of their territory, creating what David Mech and Luigi Boitani call an “olfactory bowl.” They mark more often when other wolves or coyotes intrude into their territory.
Feces: Wolves also mark territory with their feces, which they may leave on conspicuous objects and along trails and roads, often at junctions.
Saliva: A male can obtain information about a female’s reproductive state by sniffing or licking the saliva on a female’s muzzle.
Anal sacs: Because anal sacs are surrounded by muscles that a wolf can control, a wolf may secrete on command. “The common greeting position, in which two individuals stand head to tail, suggests an interest in anal sac odors,” say Harrington and Asa. The dominant wolf holds its tail away from the body, revealing the anal sac area. The subordinate animal holds its tail close.
Feet: Wolves have sweat glands in the webs of their paws that leave a scent when a wolf scratches the ground.
Skin glands: Wolves leave “distinctive odor fingerprints” that other wolves can recognize.
Back and tail: Glands in these areas may produce scents that reveal a wolf’s emotional state.
Vagina: The vagina and uterus secrete odors that play a part in long-distance reproductive communication.
Harrington and Asa add that a wolf’s sense of smell can work in conjunction with its sense of hearing to improve communication. A male wolf, for example, may smell a female’s urine and conclude that her body is ready to mate. But her growls may tell him to back off. He better listen.
[To read Part One on howling]
Wolf photo by Eilish Reding Palmer
My forthcoming book,
The Wilds of Aging:
A Journey of Heart and Mind
A Journey of Heart and Mind