Owls of Iowa
Iowa is home to nine different owl species.
You might not have seen all of them before, however, as two are state endangered — the short-eared owl and the barn owl — and one is state threatened — the long-eared owl.
Let’s take a look at some of the most interesting facts at each species, and if you want to delve in more, simply click the link for an expanded article on each!
Great horned owl (Bubo virgianus)
Great-horned owls eat small items such as rodents, frogs and scorpions, but they can also take down large birds of prey such as osprey, peregrine falcons and other owls.
A great-horned’s talons can clench with up to 28 pounds of force, and they help sever the spine of large prey.
Northern saw-whet owl (Aegolius acadicus)
Sometimes, saw-whet owls will cache their food, and in the wintertime, it may freeze before they eat it. They will then pick up what they want to eat, take it back to the roost and lay on it to thaw it before eating.
Photo by Steven Ward
Barn owls are not federally endangered but their populations are low in Iowa. That could be because of habitat loss and prey loss because of agricultural and grassland changes. They were affected by DDT use in the 20th century and could also be susceptible to rodent poison, because rodents make up a main portion of their diet. Barn owls are also prey of the larger great horned owl, which is a major threat to the existence of barn owls.
Long-eared owl
Instead of making their own nests, long-eared owls will commandeer another bird’s nest for their own use — usually from magpies, crows, ravens and hawks.
Eastern screech owl (Megascops asio)
Like other owls, screech owls are nocturnal, although they do occasionally hunt in daylight. They typically sit in trees and wait for prey to pass by, with most flights less than 75 feet. They prey on small animals as well as earthworms, insects, frogs, small birds and even bats. Sometimes eastern screech owls are cannibalistic, and siblings may even eat the smallest fledgling in the nest when food is scarce.
The barred owl has one of the most instantly recognizable owl calls, after the well-known “whoo whoo” of the great horned owl. The barred owl asks “Who cooks for you?”
Burrowing owl (Athene cunicularia)
We expect owls to be found in trees, but the burrowing owl lives in underground burrows that it digs or takes over from ground squirrels or tortoises. In Iowa, they also use badger holes. They like open habitats where they hunt for insects and rodents. Sometimes an owl will put animal dung at the entrance to its burrow, drawing in beetles and other insects that it will then eat.
They actually survive well underground because they have a high tolerance for carbon dioxide, which they expel as they exhale and can build up in their underground burrows.
Short-eared owl (Asio flammeus)
Bucking the typical owl trend, short-eared owls are diurnal, which means they are active during the day.
They hunt by flying over short vegetation in grasslands and open areas, looking for small prey such as mice and voles. They will also take down bats, and small birds. Before eating, they will decapitate their prey and eviscerate it before swallowing it whole. If it is a bird, they take the wings off before eating it.
The snowy owl is actually the largest North American owl species, weighing in up to 6.5 pounds and growing up to almost 28 inches in length. The great horned owl is just a touch smaller at 5.5 pounds and almost 24 inches long. The great gray owl isn’t found in Iowa, but it is America’s tallest owl, growing up 33.1 inches in length. The great gray owl only weighs about 3.5 pounds, though.
The reason that snowy owls are so heavy is their thick feathers that insulate them from the Arctic cold. They even have dense leg feathers, making them look quite squatty when sitting.