In your backyard or at a campsite, you may hear some interesting coos and even screeches in the night. With their beautiful arrangements of feathers, silent flight, 270-degree swiveling necks and big eyes that can stare right back at you, some of these natural species can appear other worldly.
There are about a dozen types of owls that swoop across the state of Iowa. Jim Pease, emeritus professor of ecology at Iowa State University, joined Talk of Iowa to talk about the characteristics of Iowa’s owls.
“Unlike most birds, their eyes face forward, like ours do, right?” Pease said. “And so they almost look humanish, if you will.”
The eyes at the front of their head allow owls to have better depth perception than other birds.
Owls also have large specialized facial feathers that cause their eyes to appear enlarged. This allows owls to gather more light to their eyes, which is especially helpful for hunting at night. So do the talons. On owl feet, there are two toes in the front, one in the back, and one that can rotate to the side.
“Particularly if you're going to be a nocturnal predator hunting at night, you want that sort of extra talon out to the side, just in case something tries to escape,” Pease said. "So, it’s a different toe structure than what we see for example on chickens, where you have three toes in front and one in the back. But these are very, very sharp, very strong talons.”
Another feature that makes them effective night predators is their offset ears.
“It's deliberate, because it allows them then to triangulate on sound,” Pease said. It allows them to hear from two different directions so that they can pinpoint the sound much better.”
Great horned owl
The great horned owl is the largest owl found in the state, and it’s among the most common. They stand at about two feet tall, and their head is topped with feather tufts that give them the appearance of horns.
This species also has striking yellow eyes and a stern look, as Nebbe pointed out.
“They look a little mad, if you want to do some anthropomorphizing,” she said.
Pease said these owls are known as the tiger of the woods, because they will eat just about anything. If the creature is too big to consume at once, they will pick it apart, starting with the head.
“You may find a decapitated rabbit, and you think, ‘Oh my gosh, somebody's really being ghoulish out here.’ No, it's probably an owl in the neighborhood that eats the head first,” he said. “Why do they do that? Because the brain is the first thing to decay very quickly, and it is also the highest source of protein and fat in the body.”
Barred owl
With their round face and mopey black eyes, the barred owl might look more cuddly than the great horned owl, but they are just as lethal. They go after smaller prey, such as mice and ground squirrels.
Because of their dark eyes, they are mostly day dwelling birds.
“You'll often see them about during the daytime, especially late afternoon and morning hours. Crepuscular is the word we use for that,” Pease said. “But they're also the most aquatic of the three common species, meaning you'll find them fishing. They'll actually wade in water, catching crayfish and small fish as well.”
Confusingly, barred owls are very physically similar to the spotted owl, which is a federally endangered species. However, barred owls are more aggressive than spotted owls and even sometimes kill them. This creates challenges for ecologists trying to support the spotted owl without encouraging the barred owl.
Screech owl
Another common – and arguably the most adorable – owl of Iowa is the screech owl. Coming in at about eight inches tall, they prey on small mammals such as mice and voles, as well as worms and insects.
“I think because they're smaller, maybe they don't appear so menacing,” Pease said. “Although they do look kind of angry sometimes, because they have these sort of dark lines above their eyes. And they have ear tufts, just like the great horned owl.”
Also like the great horned owl, the screech owl is a cavity nester, making homes in holes of trees. The screech owl often takes over a woodpecker hole.
Attracting owls to your yard
While the great horned owl, barred owl and screech owl are the most common in Iowa, there are a few other species can be found in the state, but are more rare. The barn owl, the short-eared owl and the burrowing owl are less likely to be spotted in Iowa because the state has lost so much of its prairie and meadow.
Pease said changing habitat is a challenge for owl species. If you are looking to encourage owls in your area, large trees in big forest areas are important for roosting at night. Owls also require mice and rabbits to feed on, so grassland ecosystems help in their survival too.
To hear this conversation, listen to Talk of Iowa, hosted by Charity Nebbe. Sam McIntosh produced this episode.
