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Syracuse Researcher Finds Wolf Subspecies Have Unique Howl Patterns
A southern drawl or a cockney accent can quickly pinpoint where a person grew up. Researchers have found that regional vocalization patterns aren’t just for humans—dialects can likewise differ among groups of wolves.
An international team of researchers, including Syracuse postdoctoral researcher Holly Root-Gutteridge, discovered that different canids, a group including wolves, coyotes and domestic dogs, all have their own ways of howling. Root-Gutteridge says, “I’ve been known to compare American wolves to jazz singers because they move around a lot vocally. European wolves are more like classical singers, where they hit a note and hold it.” The results from this study have implications for the conservation of the critically endangered red wolf.
Researchers, led by University of Cambridge Herchel Smith Research Fellow Arik Kershenbaum, compared recordings of over 2,000 howls from 13 different species and subspecies to look for group-specific differences. Recordings were accumulated from international acoustic libraries, recordings from wolf researchers and even YouTube. Domestic dogs were included in the study thanks to one tenacious intern who sifted through “many, many hours” of YouTube clips of howling pets.
The team compared vocalizations of different canids to identify differences in howling frequency. As Root-Gutteridge explains, the researchers “followed the notes wolves ‘sing.’” She continues, “For example, if you sing ‘do-re-mi,’ you’re hitting different frequencies.”
Red wolf howl courtesy of British Library Sound Archive
Differences were often found in the notes wolves howled, or how quickly they moved through them. Surprisingly, two different species, red wolves and coyotes, shared many common howl characteristics. These two species not only share overlapping ranges in the American southeast, but they have also been known to mate with one another. Hybrid matings are a major problem for protecting the genetic purity of the critically endangered red wolf. Root-Gutteridge suggests that the overlapping vocalization types of the two species may be due to their mixed genetics.
Root-Gutteridge aims to map even finer-scale differences in vocalization patterns in the future, down to regional dialects within subspecies. She says, “As an analogy, if someone has an American accent, most people recognize, ‘Oh it’s American’, but there are finer differences in dialects from North Carolina versus Texas versus Virginia. You might have to listen a little harder to pick out the latter.”
Her future plans represent a heightened level of resolution than Root-Gutteridge’s earliest research on wolf vocalizations. Prior to her Ph.D. research, she volunteered with a team investigating southern European wolves. “We’d go to the top of these Italian mountains and we’d howl at the wolves using a machine. Then we’d stand there and listen and start arguing about how many wolves were howling back to us.” While nights with no replies were easy to record, when multiple wolves responded she found it increasingly tricky to identify how many wolves and of what ages were in the area.
“From Italian mountaintops to Cambridge professors, it’s been quite a ride,” Root-Gutteridge says.
The team’s paper was recently published in Behavioural Processes and can be accessed here.
Coyote howl courtesy of British Library Sound Archive