web analytics

Why Do Wolves Howl? Decoding the Call of the Wild


Wolves howl so that they could find the rest of the pack. Image source: ScienceMag, Walter Vorbeck.

For many years, wildlife biologists suggest that the howling of a wolf is a way to reestablish contact with the rest of the pack members when they have been separated, which is a common circumstance during hunting. However, observers for captive wolves have found that the howl patterns differ from the size of the pack and the presence of the dominant, breeding wolf, indicating that the canid’s calls might not necessarily be an automatic response.

Friederike Range, a cognitive ethologist from the University of Veterinary Medicine in Vienna, has hand-raised nine wolves with her colleagues at the Wolf Science Center in Ernstburnn. The wolves in the research facility don’t hunt, yet they also howl in different occasions. “We began to take our wolves for walk when they were six weeks old, and they others would start to howl as soon as we took one of them out,” she says, “Thus, immediately we became very interested in why they howl.”

Unlike wild wolves, captive wolves don’t have natural family, hence, they form hierarchy pack in which each wolf has its “preferred partner” that it can play with, groom, and lie close to sleep. Spreading over several weeks, the scientists took each wolf out three times and walk for 45 minutes. They took the wolves randomly, so they animals were unable to predict which one in the pack was going to be removed. In almost all trails, the pack started to howl within 20 minutes after the member was took away for wall. However, the taken one usually did not return the call. Overall, the scientists noted that the wolves did most of their yodeling when the dominant member of the pack went for a walk. An individual wolf also howled more if its “preferred partner” was led away. Range believes that the wolves are not simply howling because others are, instead, the howling of wolves is reflection of the social relationship in the pack.”

The stress of separation could be one possible factor to trigger the wolves’ howls, and to evaluate this hypothesis, researchers collected wolves’ saliva samples and tested animals’ levels of the stress hormone cortisol. It is found that the stress could be connected to the amount of howling, but this is not always the case. Scientists also noted that when the dominant animal was taken out of the pack, the wolves’ cortisol levels spiked, while such significant change was not observed when their preferred partner was led away. In other words, the animals’ howls are not like the robotic responses of Pavlov’s dogs; instead of being a simple physiological response to stress, a wolf’s howl is more voluntary and driven by social factors. “The howls are strategic, not emotional,” says Range, “They try to contact individuals that are very important to them and reunite the pack.”

“The paper provides the first experimental evidence … that the main reason [for howling] is to help the pack assemble after a long hunt,” says Dave Mech, a wolf biologist at the University of Minnesota, Twin Cities. He proposed the notion in 1966 after witnessing a pack of 15 wolves hunting. At the end of that hunt, the wolves were widely dispersed, he says, but “after howling, the pack was able to assemble again.”

Dave Mech, a wolf biologist at the University of Minnesota, says, “This article provides the first experimental evidence…that indicates the main reason for wolves’ howling is to help reassemble the pack after a long hunt.” The notion was proposed by him in 1966 after witnessing a pack of 15 wolves hunting. In the end of the hunt, the wolves were dispersed widely, but they were able to assemble again after howling.

The role of howling may be quite different in the wild where an animal is free to silently follow the scent trail of others.” They also suggest that hormones other than those associated with stress may be involved in the wolves’ howls.

However, John Theberge, a wildlife biologist emeritus at the University of Waterloo in Canada, points out that it is dangerous to extrapolate conclusions from penned animals to wild ones. A wild wolf is free to follow the scent trails of others silently, and thus the role of howling might be quite different in the wild. He also suggests that other hormones rather than those related with stress may be involved in wolves’ howling. Why do wolves howl? There is plenty left to explore.

SourceScienceDecoding the Call of the Wild

Image sourceShutterstock; Science Website