With freezing temperatures, limited daylight and lengthy nights, many birds have eschewed Chicago for warmer climes. But there are still a number of hardy souls here, such as the Downy Woodpecker, Blue Jay, and Northern Cardinal. They have adopted diverse strategies that allow them to endure a Chicagoland winter.

Some birds prepare even before the chilliest season starts by caching, or storing their food for later consumption. For instance, while Red-bellied Woodpeckers stockpile food throughout the year, they begin to increase their efforts in the fall. During the winter they can then enjoy the fruits of their labor and consume, among other items in their hoard, acorns, seeds, peanuts, fruit, and insects.

Other birds who cache include the White-breasted Nuthatch, Tufted Titmouse, and Black-capped Chickadee, and you may find them foraging together in the colder months. Research done on chickadees has shown that these gray, white, buffy, and black birds are able to remember food locations for four weeks or longer. They’ve also been observed avoiding emptied caches, demonstrating an impressive recall ability. These songbirds have relatively sizable hippocampi and actually generate neurons to replace old ones to help memorize new cache locations.

*Red-bellied Woodpecker, Outagamie County, Wisconsin*
*Marie Schmidt/Audubon Photography Awards*

These are just a few birds that hide away food. But not all birds do, two examples being the House Finch and Mourning Dove, and they are able to survive through the snowfall as well. Cold-climate birds will consume more during the late summer and fall in expectation of tough months ahead, increasing their body weight and chances of surviving to the following spring. In wintertime the American Goldfinch, for instance, can have over 10% of its body weight be fat. But note that if you see a particularly rotund bird, it likely just has its feathers puffed out – an effective way for a bird to keep warm.

And certain species will sometimes travel south due to resource scarcity (not yearly migration habits). When this happens, it’s called an irruption. Irruptions occur because of an imbalance between population size and food availability – what commonly happens is an abundance of seeds from conifers in Canada and the northern U.S. leads to a higher-than-normal number of offspring. With so many mouths to feed, there may not be enough to eat by the time winter comes around, so birds need to look further south for their next meal. This scenario is why you will sometimes see birds like Purple Finches, Common Redpolls and Evening Grosbeaks during a Chicago winter; their arrival is unpredictable but always exciting.

*Redpoll*
*Robert W. Harwood/Audubon Photography Awards*

Even with these strategies, however, there may be times when the temperature dips too far down, and then, supplemental feeding can tide a bird over until the weather is more agreeable. A 1988 study by Brittingham and Temple showed that chickadees began to rely on feeders when the temperature went below -18°C/-0.4°F for 5+ days. Those who had access to this extra food source had a 30% higher overwinter survival rate compared to those who didn’t (67% to 37%). Another study published four years later, also by Brittingham and Temple, determined that this dependency was temporary for chickadees. The researchers shut off access to feeders for birds who could access them the year before and compared their survival success to chickadees who had never dined at a feeder before. There was no survival difference between the two groups. Additionally, for the former, feeders had accounted for only 21% of the songbirds’ daily energy requirements the previous year.

A perennial benefit to having a feeder is the joy people get when they can observe birds in their backyard. If you are thinking about getting a feeder, make sure that it is kept clean; unfortunately, disease can spread quickly among birds packed in one space and sharing food. Also, clean up under the feeder – discarded or fallen seeds can attract rodents.

*American Goldfinch and Evening Grosbeak*
*Susan Smith/Audubon Photography Awards*

Additionally, ensure that your windows are bird-friendly so that birds will not accidentally crash onto the clear glass. Keep in mind as well that a feeder may attract songbird predators, such as raptors and cats. If there are outdoor cats in your neighborhood, you may want to reconsider putting a feeder out.

As far as food, consider sunflower hearts, safflower seeds, suet, thistles and millet to attract a variety of birds. Sunflower seeds could entice, for instance, Black-capped Chickadees and White-breasted Nuthatches to stop by. Woodpeckers love suet cakes and American Goldfinches and Pine Siskins will go for thistle seeds. If you get suet cakes, ensure they are kept cold and don’t become rancid.

Water is also something greatly needed during the coldest time of the year; if you can, consider putting out a heated birdbath. A plastic bowl also works; just take it inside when the water freezes over. Never pour in antifreeze, which is poisonous, or glycerin, which can seep into feathers and cause hypothermia. Also, drinking glycerin-infused water may lethally raise birds’ blood sugar levels.

*Pine Siskin*
*Linda Butler/Audubon Photography Awards*

Another way to help is by planting native plants. The Chicago Bird Alliance has a native plant sale in the spring; look for notices later this year regarding the sale! Moreover, preparing your yard for winter birds actually involves less work for you. Put away the rake and leave fallen leaves where they land. Leaf litter attracts insects, leading to a good food source of bugs and larvae for birds hunkering down in Chicago. And when native wildflowers lose their petals, leave the seed heads; it may look untidy but birds now have seeds to nibble on throughout the winter.

Note that it’s not just woodpeckers and songbirds that call Chicago their winter home. The national bird chiefly eats fish, and Bald Eagles are able to find enough to dine on in Chicagoland waters. One may be able to spot eagles along the Calumet and Chicago Rivers, or further out but still near the city around the Illinois, DuPage, Des Plaines and Fox Rivers. Other locales to bird at include Big Marsh Pond and Lake Calumet.

It's a delight to be able to see birds in Chicago from December to March. Despite the ability to fly to warmer regions, some have decided to stay or stop in the Windy City and have adopted strategies to manage winter all on their own. They may not be depending on feeders, but we should not underestimate the joy that nature can bring us. So put up a feeding station, grow some native plants, and see what avian visitors stop by!

Sources

Pasquier, Roger F. Birds in Winter: Surviving the Most Challenging Season. Princeton University Press, 2019.

Do Birds Need Our Help When There’s Snow On the Ground? | Chicago News | WTTW

COMMON WINTER BIRDS OF CHICAGO

Where Is That Bird Going With That Seed? It's Caching Food for Later

Red-bellied Woodpeckers Eating and Caching Acorns | Autumn 2022 | Knots and Bolts

Not Just Birds of a Feather - The Provincetown Independent

Four Nuthatches, Four Ways to Make It Through a Cold Winter | All About Birds

What are they doing with all those seeds? - FeederWatch

Tufted Titmouse - American Bird Conservancy

Black-capped Chickadee Identification, All About Birds, Cornell Lab of Ornithology

The Black-capped Chickadee Can Swap Old Brain Cells for New Ones | Audubon