Scientists have found that wolves can be identified by the volume and amplitude of their howls — that wolves, like humans, have their own distinct voices.
To study wolves’ howls, scientists go into the wild and start (literally) howling at wolves. From doing so, they’ve learned that wolves alter the volume or amplitude of their howls just as humans stress different sounds to form different words. Holly Root-Gutteridge of Nottingham Trent University has devised a sound analysis code that, after analyzing wolves’ howls, identifies individual wolves with 100 percent accuracy.
Scientists have previously used pitch to study wolves’ howls, but have only been 76 percent accurate in identifying wolves with it.
To develop their program, the researchers analyzed 67 recordings of 10 individual Eastern gray wolves in Algonquin Provincial Park in Ontario, Canada. Their computer program was able to correctly identify individuals wolves with 100 percent accuracy. When analyzing 112 chorus howls with 109 wolves howling in unison, the program was still accurate more than 97 percent of the time.
What Are Wolves Communicating Via Howling?
Wolves howl for quite a few reasons. Howling is a way to defend territory and to identify the other members of a pack. It also has a social function: Root-Gutteridge notes that the wolves indeed seem to enjoy doing it. When a chorus of wolves start howling, others join in, suggesting that the wolves like to do this as a “group activity.”
Howling also serves what David Mech of the University of Minnesota calls a “motivating function.” “After awakening, the wolves are logy [sluggish], but after a group howl, they rush off quite motivated.” He also notes that he has “several times seen a breeding female lure a sleepy mate off to hunt by howling and then return after the male is long on his way.”
A Better Way to Monitor Wolves
Root-Gutteridge’s new code can play a useful role in monitoring wolves in the wild; it can also be used to study the communications of coyotes and other wild subspecies. Two other methods of tracking wolves in the wild have some drawbacks: one, studying the footprints they leave in the snow, has obvious limitations based on weather conditions. Another involves wolves with GPS collars. Not only are these expensive (£5,000/$7,600 each); putting them on wolves requires catching each animal, tagging them and then releasing them back to the wild. Needless to say, doing this can be disruptive to wolves and their packs, as well as possibly causing injury to them and to humans.
With the wolf making a comeback in some areas from which it had all but disappeared, including parts of Western Europe, in Yellowstone Park and elsewhere in the U.S. — a phenomenon that some are sadly not happy about — it is crucial to have an accurate sense of their numbers and range. Many populations of Maned, Ethiopian, Red, and Gray wolves are still endangered. Better understanding of what wolves are communicating can play a crucial role in helping humans understand their behavior. Wolves have plenty to howl about; it is up to us to listen.
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