The "woe is me" sound of a wolf howl is tied to loneliness and affection for others, a new Current Biology study suggests.
What's more, each howl appears to be uniquely matched to the quality of a specific wolf relationship.
This goes against prior speculation that howls are just a knee jerk reaction, with wolves acting out of instinct instead of anything particularly meaningful.
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"Our results suggest the social relationship can explain more of the variation we see in howling behavior than the emotional state of the wolf," Friederike Range of the Messerli Research Institute at the University of Veterinary Medicine Vienna, who worked on the study, said in a press release.
"This suggests that wolves, to a certain extent, may be able to use their vocalizations in a flexible way."
Range and colleagues' study looked at two packs of wolves living at Austria's Wolf Science Center. Human handlers there typically take individual wolves out for walks on a leash, one at a time. The handlers noticed that, without fail, the other wolves would howl when one of their pack left them.
The researchers measured the howling wolves' stress hormone levels to see if sheer anxiety led to the howling. They found that the amount of howling did not correspond to higher levels of the stress hormone cortisol.
Range said, "Our data suggest that howling is not a simple stress response to being separated from close associates but instead may be used more flexibly to maintain contact and perhaps to aid in reuniting with allies."
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Collected data on the wolves' dominance status in the pack and their preferred partners determined that wolves howled longer and with more gusto when the missing wolf was a close compatriot and if the individual was of high status within the pack.
One other thing to keep in mind is this week's Blue Moon. A lot of legends hold that wolves and dogs howl more when there is a full moon like this. Science supports some of those stories, since the extra light means more animals tend to be active at night.
So the next time you hear a wolf howling, know that it is probably lonely and calling out to its missing pack mate, hoping he or she will come back soon.
(Image: Mazzini et al.)