Mournful Wolf Howl Reveals How Wolves Care for Their Friends

The mournful call of a wolf may not just be a way to contact others. Wolves may also howl in order to show that they care. Researchers have discovered that these canines howl to show the quality of their relationships when a wolf leaves a pack.

Animals of all sorts make sounds to communicate to one another. For example, birds sing in order to establish territory and frogs croak in order to find a mate. Yet scientists have often wondered whether animals have the ability to change these vocalizations based on their own understanding of social context. In order to look at animal noises a bit more in depth, the researchers studied nine wolves from two packs living at Austria's Wolf Science Center.

At the wolf center, handlers typically take out wolves for walks on a leash one at a time. When they do, the rest of the pack mates that are left behind usually howl. This particular behavior intrigued the researchers.

In order to better understand why the wolves howled, the scientists measured the wolves' stress hormone levels. They also collected information on the wolves' dominance status in the pack and their preferred partners. Then, they took individual wolves out for long walks and recorded the reactions of each of their pack mates.

So what happened? It turned out that wolves howl more when a wolf they have a better relationship with leaves the group and when that individual is higher up the social ladder. Yet the wolves weren't stressed. It turned out that the amount of howling did not correspond to higher levels of the stress hormone cortisol.

"Our results suggest the social relationship can explain more of the variation we see in howling behavior than the emotional state of the wolf," said Friederike Range, one of the researchers, in a news release. "This suggests that wolves, to a certain extent, may be able to use their vocalizations in a flexible way."

The findings reveal that a wolf's howl is not a simple stress response. Instead, it may be a way to maintain contact with separated wolves or aid in reuniting with allies.

The new study is published in the journal Current Biology.