Melissa McLeod, a former Detroit Audubon Society Safe Passage program volunteer and a photographer who runs the Feral Detroit Instagram account, said she documented some of the dead birds herself and began uploading data into the Birdmapper.org website.
“There’s not a lot of people doing it on their own,” she said. “I started doing it when I found them. Once you see this is a thing, you can’t really unsee it.”
Efforts to track more bird collisions with buildings outside of the Wayne State University campus area where the Detroit Audubon Society is based, so far, have not been successful, she said.
In a sense, Detroit and its suburbs aren’t unique.
“There’s no question Detroit kills birds because any place you put buildings that have light, that happens,” Farnsworth said. “It’s a question of what the magnitude is. There are nights in New York and Chicago where people find hundreds or thousands of birds at the base of buildings sometimes where there are significant mortality events.”
According to the Detroit Audubon Society, birds use the stars and moon for navigation during their migrations and building lights disorient them.
“They circle the buildings repeatedly and either die of exhaustion or colliding with the illuminated building,” the society says on its website.
And the region is particularly highly traveled, said Ben Winger, associate professor and assistant curator in the Museum of Zoology at the University of Michigan in Ann Arbor.
“Southeast Michigan is a major thoroughfare for migratory birds in the Great Lakes and we are right at the western edge of Lake Erie, which funnels a lot of bird migration along its shores of migratory songbirds, shore birds and water birds,” he said.
Songbirds are in particular at risk because they are smaller and tend to congregate, Winger said.
The combination of high bird migration volume and its light volumes at night make the Detroit region high-risk for the collisions, he said.