The pair of peregrine falcons in Burton Tower get the press, but the real raptor story in Ann Arbor is the growing number of hawks in town. In December, a Cooper’s hawk was seen flapping down Alhambra, a full-sized squirrel hanging limply from its claws. Days later in the same southwest-side neighborhood, a red-tailed hawk plunged down out of a clear sky, ripped a small bird from its nest at the top of a maple tree, then banked hard and soared off.
“A Cooper’s hawk will eat other birds—including robins and cardinals—as well as small mammals,” explains Dea Armstrong, the chief ornithologist with the city’s natural area preservation unit. Their bigger relatives go after bigger game. “I’ve seen red-tailed hawks hunting in my yard for chipmunks, squirrels, even rabbits if they’re small enough,” says Armstrong.
The squirrels might not agree, but “hawks have a very positive impact on our environment,” says Francie Krawcke, director of the Leslie Science Center’s raptor program. “They take care of a lot of the pests—rodents, moles, voles, and mice, even groundhogs. They can carry something up to half [their] body weight.”
Hawks are having a positive impact on our environment because we’re no longer having a negative impact on them through insecticides. “Back in the ’70s, things were awful for raptors,” Armstrong explains. “The DDT would be ingested by lower members of the food chain, then it would be ingested by hawks and other raptors, and they’d have terrible soft eggshells and new birds born with misshapen beaks. But they’ve all made huge comebacks. Look at the bald eagle. There were 500 in the country. Now there are 500 in Michigan alone.”
Neither Armstrong nor Krawcke can say for sure how many hawks are in town. But “there are more than there used to be,” says Krawcke. “Dozens at least.”
Armstrong can be a bit more precise. “For my Christmas bird count, we found nine red-tailed hawks from 8:30 to 2:30 in a very small area north of North Territorial Road. We saw one Cooper’s hawk, but the Cooper’s hawks are in the woods—you don’t see them, because they’re well concealed.”
The Washtenaw Audubon Society survey counts the actual numbers of birds seen in a single 24-hour period. Armstrong says volunteers saw an average of about seventeen Cooper’s hawks a year during the 2000s, up from about ten in the 1990s. The red-tailed count has averaged about thirty-four over the last decade. Armstrong guesses the real numbers of both types of hawks could be double the counts.
The count covers a 15-mile radius from the center of Ann Arbor, and many hawks, like the group Armstrong saw, live in the nearby countryside. But they show no fear of the city. “Cooper’s hawks are all over town,” says Armstrong. “I’ve seen them hunt on the Diag. But that’s nothing—I’ve seen red-tails hunt on the Diag.”
Armstrong can top even that. She’s seen Cooper’s hawks nest near her north-west side home. “Somewhere around here I have a picture of three young Cooper’s hawks perched along the edge of a bench in my backyard,” she says. “It’s quite a sight!”
This article has been edited since it appeared in the February, 2011, Ann Arbor Observer. The photo caption and the street where a hawk was seen carrying a squirrel have been corrected.