About Bird Migration 

With spring right around the corner, you might notice more birds flying through during the spring migration. In Chicago, spring migration typically ranges from mid-March to early June, peaking around mid-May. The Windy City sits on a major migratory route in North America called the Mississippi Flyway; over 250 bird species migrate through Chicago during this season, totaling up to 8 million individuals. So, how is bird migration relevant to our lives as human beings?

For starters, both birds and humans migrate and, sometimes, for the same reasons. The leading factors behind bird migration connect to evolutionary and reproductive success: birds migrate to find mates, make nests, and live where there are enough resources to raise offspring. This process isn’t anything new–recorded instances of bird migration date back thousands of years, and it is generally understood that birds have been migrating for millions of years. Perhaps one of the most interesting historical cases leading to the modern study of bird migration was in 1822, when a group of German villagers struck down a white stork only to find that the bird was already impaled with an African spear. This extraordinary instance was one of the first concrete pieces of evidence behind long-distance bird migration, though reliable records show people observing and studying migration in the 13th century. 

In the migratory sense, birds and humans are alike. Both are travelling creatures, seeking opportunities to thrive and lead successful lives. Aside from this shared experience, however, there are more reasons Chicagoans should care about bird migration in the area. Birds play a significant role in our local ecosystem; from predators to prey, birds provide integral services to the natural world. For this reason, bird migration is vital to a healthy landscape, even a city, meaning the conditions to ensure a successful migration are vital, too. Over the past half-century, North America has seen steep declines in bird populations due to habitat destruction from expanding development and agriculture, and invasive species crowding out and degrading the remaining habitat. 

The Challenges of Bird Migration

The city of Chicago brings another conflict to bird migration: our high-rise buildings and skyscrapers stand as obstacles on migration routes, confusing birds and causing an unfortunate amount of bird deaths. The “Lights Out” Initiative, led by Chicago Bird Alliance (formerly Chicago Audubon Society) alongside the Building Owners and Managers Association, the National Audubon Society, and the City of Chicago, encourages Chicagoans, particularly those who own or live in tall buildings, to dim or turn off their lights to aid birds in the area. The initiative claims to have saved over 10,000 birds annually since 1995 due to buildings in the loop participating in the program. Other benefits include energy conservation and lower maintenance costs–things people can generally get behind. 

On the flip side, a volunteer network called the Chicago Bird Collisions Monitors (CBCM) works to save birds who have fallen victim to building collisions. The CBCM estimates that “up to a billion birds die and countless others are injured each year in North America as a result of window collisions,” vowing to protect migratory birds and advocate for bird-safe lighting and building design. The idea behind bird-safe buildings, as well as the Lights Out initiative, is to help birds navigate around glass. When the lights are on, birds confuse windows for openings and crash into them. Here are some examples of bird-safe buildings! One story of success is the McCormick Center, a glass building that once claimed the lives of 1,000 birds in one night. However, after implementing bird-safe windows, collisions decreased by 95%.

Migratory route hazards aren’t the only factor when it comes to a successful migration. Humans can also manage parts of the landscape as habitats to make sure birds have healthy resources along their route. Planting native plants outside your home and in your neighborhood provides a healthy habitat for migrating birds. Native plants host native insects, seeds, and fruits that migratory birds are adapted to eating. Avoiding insecticides is a great way to ensure various toxins don’t plague local birds who rely on eating insects, which are baby birds’ primary diet. Even birds that eat seeds as adults depend on insects when they’re younger.

This spring migration season, do as much as you can to create a comfortable environment that sets our flying friends up for success. Bird migration is definitely a time to tune in to nature, and there are many ways to see it! Some of the best places to look for migrating birds are around water, such as Lake Michigan, the Chicago River, and in Lincoln Park at North Pond. There are plenty of native migrating birds to find! You might catch the Ruby-throated Hummingbird at the Lily Pool migrating back to Chicago after a winter stay in Southern Mexico, Central America, or around the U.S. Gulf Coast. Green herons will also be returning from a similar vacation!