Many years ago, while running along the Lake Michigan shoreline late on an evening in January, a feathered ghost appeared on top of a flag pole. It was the first time I had ever seen a snowy owl (Bubo scandiacus) and it stopped me in my tracks. This was the spark on that frozen night that lighted my fire of curiosity about birds. This winter, snowy owls have left their Arctic homes in record numbers, causing one of the largest irruptions (sudden increase) in northern Illinois in decades.
Although it seems natural to correlate the arrival of these boreal birds with the extremely cold, snowy winter northern Illinois is having, experts say the motivator is more likely linked to food. On their Arctic breeding grounds, snowy owls feast under 24-hour sunshine. Their food of choice is lemmings, small mammals with an extremely cyclical population. Bird expert Kenn Kaufman explains in a recent Audubon magazine article, that when the lemming population explodes, like it did last summer in northern Quebec, snowy owls have great breeding success, producing large broods of up to 11 chicks. As these chicks quickly grow into juvenile birds, the competition grows for the now dwindling numbers of lemmings. Thus, the young birds get nudged further and further away to find a meal, resulting in them moving to areas that mimic their treeless tundra home, such as the Lake Michigan shoreline.
Local shorelines have become one of their adopted midwestern homes, where they feast on ducks, gulls and rodents in broad daylight. Most snowy owls spotted out of their breeding range are immature birds. These juveniles are distinguished from adults by heavier black markings on the body compared to the older birds’ whiter plumage.
One great way to find out where you can see one of these fascinating birds is to check out IBET (Illinois Birders Exchanging Thoughts) for sightings from local birders. Remember to keep your distance when viewing the young birds, who are stressed and vulnerable from their lengthy travels. Be sure to bring binoculars or a powerful scope to help get the best views.
If you are looking for a “spark” during these cold days, scan the Fort Sheridan Forest Preserve shoreline to see if you can catch a glimpse of this ghost from the north. Want to learn more about our resident owls? For a nocturnal adventure, join a Lake County Forest Preserves naturalist on the upcoming Hoot and Howl Hike.