Owls, with their silent flight and captivating presence, are a source of fascination. Iowa’s varied ecosystems provide suitable habitats for several owl species. Their ability to adapt to different settings, from dense woodlands to open grasslands, allows them to thrive across the state.
Iowa’s Common Resident Owls
The Great Horned Owl, a large and powerful predator, is a common year-round resident across Iowa. Known for its prominent ear tufts and deep “hoo hoohoo hoooo hoo” call, this owl exhibits remarkable adaptability, inhabiting forest edges, woodlands, and fields. Its diet is broad, encompassing rabbits, squirrels, smaller owls, and even skunks, which it hunts during evening and nighttime hours.
Another prevalent year-round resident is the Barred Owl, a medium-sized, stocky gray owl with large dark eyes. These owls prefer mature forests and wooded areas near waterways for roosting and nesting. Their characteristic vocalization is typically heard in late winter as they establish nesting territories. Barred Owls primarily consume mice, but their diet also includes other small mammals, birds, reptiles, amphibians, and invertebrates.
The Eastern Screech-Owl, a smaller owl, can also be found throughout Iowa year-round. This species displays variable plumage, ranging from gray to brown or rufous, allowing it to blend seamlessly with its surroundings. Screech-owls often roost in tree cavities or dense foliage during the day. Their prey consists of mice, moles, shrews, and occasionally small snakes, frogs, and insects.
Seasonal and Migratory Owl Visitors
Iowa also hosts several owl species that are seasonal or migratory visitors, particularly during the colder months.
Snowy Owl
The Snowy Owl is an irregular winter visitor to the state. These distinctive white owls breed in the Arctic tundra, and their presence in Iowa is often linked to successful breeding seasons and subsequent scarcity of primary prey like lemmings in their northern breeding grounds, leading to “irruptions” southward. They prefer open areas, such as agricultural fields and airports, which resemble their native tundra habitat.
Short-eared Owls
Short-eared Owls are regular winter visitors to Iowa. These owls are readily identified by their short ear tufts and their habit of hunting during daylight hours, often flying low over open grasslands, marshes, and agricultural fields. Their diet mainly consists of small mammals, especially voles and mice, and their presence often indicates high rodent populations. Short-eared Owls are unique among owls for being ground nesters, creating shallow depressions lined with vegetation.
Long-eared Owl
The Long-eared Owl is a winter visitor in Iowa. While similar in coloration to Great Horned Owls, they are smaller with notably longer ear tufts. These owls often roost communally in dense conifer stands or mixed conifer-deciduous areas, but they forage in adjacent open grasslands. Their diet consists mainly of small mammals, such as voles and mice, which they primarily locate by sound.
Northern Saw-whet Owls
Northern Saw-whet Owls, the smallest owl species found in Iowa, are common winter visitors. These tiny owls prefer dense vegetation, particularly conifers, for roosting during the day. Unlike many larger owls that swallow prey whole, Northern Saw-whet Owls consume their primary prey, woodland mice, in pieces over several meals. They are highly nocturnal and often go unnoticed due to their secretive nature.
Rare and Declining Owl Species
Some owl species are rarely sighted in Iowa or face challenges leading to declining populations within the state.
Barn Owl
The Barn Owl, recognized by its unique heart-shaped face and light underparts, is considered a rare permanent resident in Iowa, listed as endangered since 1977. Iowa represents the northern extent of their range, and their populations are primarily limited by severe winter conditions. These owls rely on grassland habitats for hunting voles and mice and prefer nesting in old wooden barns, tree cavities, or abandoned buildings. Habitat loss, such as changes in land use and removal of old structures, poses significant threats.
Burrowing Owl
The Burrowing Owl is a casual visitor to Iowa, with few nesting records. These small, long-legged owls are unique for nesting and roosting in burrows, often those dug by prairie dogs or badgers. They prefer dry, open areas with short grasses, a habitat type that is limited in Iowa. Burrowing Owls hunt both day and night, primarily for insects like dung beetles and small mammals. Their infrequent presence makes any sighting noteworthy for bird enthusiasts.