Sandhill cranes. (US Fish and Wildlife Service Midwest Region)
They came back.
Red-winged blackbirds, American robins and sandhill cranes are among the bird species Chicagoans have spotted in recent days on the leading edge of spring migration.
But wait – according to the calendar, it's still winter.
Is it too early for birds to travel north?
As images of their latest sightings are shared online, birders and casual observers debate whether the timing is really off.
Some attribute the early arrivals to a warmer El Niño weather pattern. Others say it's a more insidious sign of climate change — “We know we've really messed up the environment when you see a robin in Chicago in the first half of February,” one North Sider posted on social media — while a third faction is insisting that such sightings at this time of year are not unusual.
The truth, experts say, is “all of the above”.
“I tend to caution people against jumping to conclusions,” said Stephanie Beilke, senior director of conservation science at Audubon Great Lakes. “But I'm glad people are paying attention.”
Robins were considered harbingers of spring, but many live in Chicago year-round. (US Fish and Wildlife Service Midwest Region)
When it comes to migration, most people's general understanding of the phenomenon is an oversimplified version of a complex process, said Edward Worden, president of the Chicago Ornithological Society.
While the idea of birds flying to Canada and the U.S. in the spring and then heading to Central and South America in the fall holds true for some migratory species, the movement of others is more variable, Warden said.
Robins—long called the “harbingers of spring”—migrate, but many stay in Chicago year-round. The same goes for red-winged blackbirds. Others, like great blue herons, will adapt on the fly, so to speak.
“If it's cold and the water freezes, they leave. If it doesn't, they stay,” Warden said. “They think, 'If I don't have to migrate, why should I?' Why spend all that energy if you don't have to? Birds move as they see fit. The patterns are not strict or the same year after year.'
For those leaving Chicago, “southern” migration may actually mean only a hundred miles or so, to central or southern Illinois and Indiana, where it is slightly warmer and food is more available.
These species, including the red-winged blackbird, are usually the first birds seen in Chicago, having a much shorter distance to travel, according to Beilke.
“Seeing a red-winged male in February is not particularly unusual in Chicago,” he said, noting that while the females won't emerge until May, the males rush to prime breeding territory.
Indeed, Beilke said she always records a red-winged blackbird during the annual Counting birds in the backyard, which takes place in mid-February. (Counting is ongoing until February 19. Click here for information on how to participate.)
A significant number of sandhill cranes also winter in lower Illinois and Indiana. “These birds,” Beilke said, “have more flexibility with their schedule and can understand weather conditions.”
And if they misjudge those cues, some have been known to turn back, he said, adding that “we do see mortality occurring” during snowstorms in late March or April.
Male red-winged blackbirds arrive in Chicago in February to find the best breeding sites. (US Fish and Wildlife Service Midwest Region)
That said, it's been an unusual year weather-wise, Beilke acknowledged, and some birds could respond to milder-than-normal temperatures.
It's hard even for scientists like herself to tell the difference between behavior affected by individual weather events and climate change, Beilke said.
That's why researchers rely on long-term data sets such as the Christmas Bird Count (dating back to 1900), yard counts and submissions to the e-bird platform, which help scientists compile a picture about birds found where and when.
This data shows that some birds, including the Swainson's thrush — which passes through Chicago on its journey — are actually migrating earlier now than they did 60 years ago. The concern from a timing standpoint, Beilke said, is that if the birds move earlier, they may not find matching food resources along their route.
Other birds are expanding their breeding range further north, including arctic terns that could literally run out of space at some point, Beilke said. And other species are vulnerable if climate change significantly alters their breeding habitat.
Beilke pointed to the red-headed woodpecker as one such species to watch. Hot summers and drought could make the current region – temperate North America – inhospitable and push the birds into northern Canada. The problem, Beilke said, is that these woodpeckers eat a lot of acorns and beech nuts, and if the birds end up in Canada's pine forests, they won't get what they need.
The seeds of native plants such as echinacea (conifers) can provide food for early migratory birds. (Alan Levine/Flickr Creative Commons)
The bottom line, Beilke said, is that it's normal to see some birds return to Chicago in February, but there are signs that some species migrate earlier.
In the long term, we can help the birds by preventing further climate change, he said, but in the short term there are things people can do to make Chicago more comfortable for these early birds.
One option is to turn off the suet feeders during the “false spring,” when insects are scarce, Beilke said. Another is to make yards more resilient—less grass, more native plants. And choose natives that provide fruit or seed—just be sure not to “tidy up” the garden in the fall and cut off all the seed heads.
Finally, protect the region's parks, forest preserves and other natural areas, which provide birds with vital oases, Beilke said.
As for whether Chicagoans actually see birds earlier than 2024, Beilke said what matters most is that people are asking.
“I'm glad people are paying attention,” he said. “We have to watch for things that seem strange. If you see something, you're probably not the only one.”
Contact Patty Wetley: @pattywetli | (773) 509-5623 | [email protected]
