Illinois offers diverse habitats, from hardwood forests and river bottoms to agricultural fields and urban parks. These environments create a refuge for several owl species, making the state an excellent location for observing these nocturnal raptors. Owls are secretive predators, often revealing their presence only through distinctive vocalizations under the cover of darkness. Understanding their biology and habitat requirements is the first step toward appreciating their silent presence.
Primary Resident Owls of Illinois
The Great Horned Owl is a large, adaptable year-round resident found statewide in nearly every habitat type, including city parks and suburban areas. It is easily recognized by its prominent feather tufts, often mistakenly called “horns” or “ears,” and its mottled brown and gray plumage. This owl produces the classic, deep, five-part hooting call, often transcribed as “hoo, hoo-oo, hoo, hoo.” This call is typically heard from late fall through early spring as pairs establish territories and begin nesting.
The Barred Owl is a common permanent resident, often associated with bottomland forests and swamps, especially those near water. This species is unique among Illinois’ larger owls for its dark brown eyes and the lack of feather tufts, giving its head a round appearance. Its vocalization is one of the most recognizable in the woods, a series of hoots that sounds like the phrase, “Who cooks for you? Who cooks for you-all?”.
The Eastern Screech Owl is the smallest of the common residents, averaging seven to ten inches in length with a compact body and small feather tufts. This small owl is found in woodlands, orchards, and wooded residential areas across Illinois. The species exhibits two color phases, a gray morph and a reddish-brown (rufous) morph, both providing excellent camouflage against tree bark. Its distinctive call is not a hoot but a wavering, descending whinny, similar to a horse.
Seasonal and Specialized Owl Species
The Northern Saw-whet Owl is one of the smallest owls in Illinois and is primarily an uncommon winter resident and migrant, arriving in late fall. This tiny raptor lacks feather tufts and prefers to roost in dense coniferous trees or thick understory vegetation during the day. Because of its size and camouflage, it is difficult to locate. Its presence is often only detected through banding efforts or by searching these dense roosting spots during the day.
The Short-eared Owl is a highly specialized species that is an uncommon migrant and winter resident, considered state-endangered due to habitat loss. Unlike most owls, this bird is often active during the late afternoon and early morning (crepuscular). It hunts over large, open areas like native prairies, marshes, and agricultural fields. When seen, its flight pattern is distinctively buoyant and moth-like as it flies low to the ground.
The Long-eared Owl is a winter visitor, arriving around October and departing by April. It prefers to roost communally in dense groves of conifers or thickets near open hunting fields. This slender species has long, closely set feather tufts. Its camouflage is effective, often allowing it to go unnoticed as it blends with the tree trunk. Its presence is often indicated only by the accumulation of regurgitated pellets beneath its daytime roost.
The Snowy Owl is an irregular winter visitor from the Arctic tundra, arriving primarily during “irruption” years when northern prey populations are low. These birds are found mainly in the northern half of the state, favoring wide-open landscapes. They seek areas like lakefronts, large agricultural fields, and airport grounds that mimic their treeless breeding habitat. They are unique because they are active during the day, increasing the chances of observation compared to nocturnal owls.
Practical Guide to Owl Observation in Illinois
Successful owl observation relies on proper timing. The most opportune times for locating owls are during the crepuscular hours of dusk and dawn when nocturnal species become active or return to their roosts. Winter is often the best season for viewing, as migratory species arrive, and leafless trees make resident owls easier to spot.
Interpreting the landscape is crucial, as different species favor distinct terrain for hunting and roosting. Look for the Long-eared Owl and Northern Saw-whet Owl in dense stands of cedar, pine, or other conifers, particularly near the edges of open meadows. The Short-eared Owl requires expansive, open grassland or prairie habitats, where it can be seen flying low over the fields.
Ethical viewing practices must prioritize minimizing disturbance, as owls rely on undisturbed rest during the day to conserve energy for night hunting. If an owl appears to be watching you, frequently turning its head, or sitting upright with its eyes wide open, you are too close and should immediately increase your distance. Avoid flash photography, as this can disrupt an owl’s vision and hunting ability after dark. The use of recorded calls, sometimes called “hooliganing,” should be avoided, as playing calls causes stress and disrupts natural behavior. Always use binoculars or a spotting scope for viewing and a telephoto lens for photography to maintain a respectful distance.