Another winter. Another congregation of crows in Terre Haute.
The city continues its annual struggle to cope with an influx of thousands, and often tens of thousands of American crows, from their October arrival to their March departure. Downtown residents, workers, businesses, churches, lodges, restaurants, motorists and pedestrians encounter the birds and their gooey residue, just as they’ve done since the invasion began in the 1990s.
We know the drill, but how well do we know the crows? A new research project could tap into their crafty brains.
Sure, the community better understands the creatures, after all these years. We know crows are smart. They catch onto human tactics to disrupt their nighttime habits of roosting in trees and on buildings downtown. Those efforts have been intense at times, such as the 2010 formation of the Terre Haute Crow Response Committee, but routinely, the difficult, daily task of using pyrotechnics and lasers to scatter the birds falls to the city Code Enforcement crew.
Art galleries have hosted crow exhibitions. Local musicians name bands after the crows (though none yet include the scientific moniker — corvus brachyrhynchos).
Terre Haute even counts its crows. Birders spotted 9,959 in just two daytime locations during the Wabash Valley Audubon Society’s Christmas Bird Count last month. Estimates of the overall number of roosting crows downtown have ranged from 80,000 to 20,000.
As crow-enlightened as Hauteans have become, much about them remains a mystery. Unraveling the unknowns could help develop better methods of steering them away from the heart of the city. Researchers at the University of Washington’s campus in Bothell may uncover some answers about how crows communicate and react to each other, and to outside forces.
Two professors at the 5,735-student UW-Bothell campus and a team of undergraduates are recording the calls and movements of crows that typically gather atop university buildings before the birds hunker down in trees for the night. The researchers have positioned audio and video equipment on the rooftop of a prime crow hangout, capturing the caws and the reactions caused by those sounds.
The professors’ expertise matches the subject matter. Douglas Wacker is an assistant professor of animal behavior in the school’s biological sciences division. The native Hoosier, who grew up in Brownsburg, studied birds but never crows until joining the UW faculty in Bothell, a college town near a wetlands that began attracting large numbers of crows about a decade ago. His cohort in the study is Shima Abadi, an assistant professor of mechanical engineering. She’s an ocean acoustics expert who’s recorded whales with underwater microphones.
Their students, and all others at UW-Bothell, must complete research projects, and many have chosen to analyze various aspects of the crows because of their growing numbers and the close proximity to the birds’ wetlands food source. This school year’s project presents a new twist. Students are trying to unlock the crows’ communications.
To a frustrated Hautean, the caws of the crows probably sound repetitive, but the calls actually vary. So, the Washington researchers are charting the number of caws — such as “caw-caw-caw” or just “caw” — and pauses in between, the pitch, and the crows’ responsive behavior.
“We don’t have the Rosetta Stone of crow-like language ... at this point,” Wacker said by phone Tuesday from Bothell. “We don’t know exactly what we’ll find out.”
He’s got a hunch, though. Crows could be communicating about people, other creatures or objects in their immediate environment. Or trying to announce their location to other birds. Or, perhaps most intriguing, crows could be alerting others about food sources they’ve scouted elsewhere. “If we found that, it would be fantastic,” Wacker said.
The students and professors hope video reveals the impact of the caws on fellow crows. “Do they approach the calling crow? Do the move away from the calling crow?” Wacker asked, rhetorically.
The researchers’ potential discoveries have a value beyond mere curiosity, especially to cities where crows choose to winter — Terre Haute; Danville, Ill.; Auburn, N.Y.; Lancaster, Pa.; and others. “Perhaps we can find less invasive ways to dissuade them from aggregating in particular places,” Wacker said.
That would be cause, pun intended, for celebration in Terre Haute.
Mark Bennett can be reached at 812-231-4377 or firstname.lastname@example.org.