Why thousands of crows visit downtown South Bend at night

Allisyn-Marie Gillet counts this as one of her favorite parts of winter: the huge swaths of American crows — hundreds of them, even thousands — that fly through cities like an avian river.

“There can be miles of crows,” the state ornithologist for the Indiana Department of Natural Resources says. “It’s amazing.”

This winter, several of us have witnessed massive numbers of crows settling in downtown South Bend near sunset. They cross over the river … over the Century Center island … over neighborhoods … and fill the tops of the tallest trees that they can find.

Why downtown? Why this winter?

These gatherings of crows, called roosts, happen every winter in urban areas. If you’ve watched locally, you’ve noticed that their winter roosts have shifted about South Bend and Mishawaka from one year to the next. But it has nothing to do with Alfred Hitchcock, with scaring you or with finding food. It’s more about trying not to BE food, Gillet says. And staying warm.

“It’s all about protecting yourself,” she says.

There is safety in big numbers, she adds, explaining: “If there are any predators, you have a lot of eyes around to keep an eye on the landscape and let others know.”

So the crows seek out big trees that can support their prodigious numbers and provide a good view of predators.

Who’d eat them? The most likely suspect, Gillet says, is the great horned owl.

In fact, some people post owl decoys along their rooflines to deter crows. The McDonald’s in downtown has several of them along its roof. The restaurant is near big trees, and I’ve seen crows drifting overhead there.

But Gillet says of the decoys: “It doesn’t work. Save your money. They’re (crows) much smarter. They know whether that thing is alive. Sometimes they even get habituated to it.”

In fact, crows have relatively larger brains and are known to be among the smartest species of birds, which researchers have proven with math and memory tests.

I wrote about crow roosts in 2015, too. In that piece, ornithologist Doris Watt at Saint Mary’s College, who was retiring after doing most of her research on bird behavior in social flocks, described the crow roosts as “accidental gatherings,” drawn together “because the place is good.”

March 2015:Crows congregating by the hundreds

She suspected that roosting is an example of the “selfish herd hypothesis,” where birds are constantly shuffling to get inside of the group, making it harder for a predator to eat them.

Roosts form near sunset so that, as they sleep at night, birds can avoid nocturnal predators like owls.

Crows tend to form roosts in urban areas partly because of the visibility, thanks to city lights.

But cities also are relatively warmer because of the buildings, concrete and vehicles. Perhaps the crows’ large numbers also generate heat, too.

During the daytime in winter, the crows disperse to feeding areas. And, in the breeding months of summer, Gillet says, this whole social phenomenon goes in reverse as crows become more territorial, defending their own unique nesting areas.

Overall, the numbers here grow in winter because other American crows up north come south for our balmier temperatures, she says. Likewise, some our resident crows may be “sunning” themselves somewhere to the south — just not very far because, as “partial migrants,” they aren’t like the birds who make it to Florida.

Also in this column:Do the Mishawaka Riverwalk among lights or prowl for night critters

Of course, big numbers can mean a fair amount of bird droppings. Gillet says that shouldn’t be a big health concern as long as you practice good hygiene. It’s simply a matter of washing your hands if you come in contact with the waste or anything that touches it.

Likewise, crows aren’t a big risk for the avian flu, she says, because they don’t mingle with birds that commonly do carry the virus, such as geese and other waterfowl.

They are a naturally noisy bird, making an array of cackling and gurgling sounds. Their basic call may just be to let others know they are there, which may attract others to the group or help to keep them together, Joel Ralston, an ornithologist and associate professor at Saint Mary’s College, says.

Another bird that roosts locally is the chimney swift, with hundreds or thousands that gather at night — especially as a stopover during spring and fall migrations — around and inside the tall brick chimney of Columba Hall on the University of Notre Dame campus.

May 2022:The chimney swift spectacle in our backyard: Thousands of birds return to Notre Dame

Two years ago, experienced bird watcher and counter Kyle Wiktor says he and a friend counted at least 19,500 crows one January night at a recurring roost near the South Bend Ethanol Plant, which is along Calvert Street on the city’s west side. But Wiktor, who lives in the Chicago area but has family in South Bend, felt a more accurate count would have been thousands higher because he didn’t have enough other people to count crows that were on the move.

In checking with a regional bird expert, Wiktor learned that may have been among the largest American crow counts in Indiana.

For the past five or so Decembers, Ralston has found a crow roost at the heavily wooded Rum Village Park where, on the one-day Christmas Bird Count in South Bend, he’s headed at sunrise to count the number of crows. The numbers vary from year to year, he says. He counted roughly 300 at Rum Village this past December, but surely there were more, because he also saw them flying out toward their daytime feeding spots.

It may not be every single night that you see the crows roost in downtown. Exactly where they end up may depend on where they spend the day, Ralston suggests.

He, too, relishes this time of year when, he says, "as I’m going to my car, I see this river of crows.”

“It’s an opportunity,” he adds, “to observe a neat natural phenomenon.”

Want more birds?

∎ Bird count at Lydick Bog: You don’t need to know much about birds to join this count at 8:30 a.m. Feb. 18 at Lydick Bog Nature Preserve, 25898 U.S. 20, South Bend, west of the St. Joseph County Valley Parkway. Experienced birders will lead the count from the local Audubon Society and the Shirley Heinze Land Trust, which owns the preserve, with unpaved trails, a wetland boardwalk and bog platform. This is part of the international Great Backyard Bird Count, contributing data for citizen science. New to birding? Download the Merlin Bird ID app to identify birds using a photo and audio. Findings can be uploaded to the eBird Mobile app.

∎ Wednesday bird walks: An Elkhart County Parks naturalist leads a free, bird-seeking hike from 8 to 10 a.m. on the first Wednesday of each month all year. On March 1, the hike looks for sparrows at Benton Spillway in River Preserve County Park, one mile south of U.S. 33 on County Road 31 in Goshen. On April 5, the hike looks for singing birds at the Lookout Shelter near Bonneyville Mill County Park’s main parking lot, 53373 County Road 131, Bristol. And on May 5, it seeks warblers at the Baintertown Dam at River Preserve County Park, 18000 County Road 142, New Paris. Find more details at elkhartcountyparks.org.

Find columnist Joseph Dits on Facebook at SBTOutdoorAdventures or 574-235-6158 or jdits@sbtinfo.com.

This article originally appeared on South Bend Tribune: American crows roost in downtown South Bend in huge numbers