Photo of a barn owl on a postWe've talked about the large great horned owl, tiny northern saw-whet owl and adorable eastern screech owl, so this week we moved on to the state endangered barn owl.

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.

They are an incredible creature and are easy to tell apart from other owl species because of their heart-shaped white face.

Photo of a barn owl's face

Barn owls do actually like barns as well as other abandoned buildings, rock cavities and densely treed areas, and they will search for prey at night by flying low back and forth over open habitat, listening for rodents to make sounds. They actually eat their prey whole, later regurgitating bones and other indigestible body parts in what is known as owl pellets --- basically owl vomit. It makes it easy to see what a barn owl has eaten.

Female barn owls actually use their own pellets to make nests, shredding them and rearranging the pieces into a cup-shape for up to 18 eggs in a clutch. Barn owls may roost in the nest year-round, instead of simply using it to rear young. They are usually monogamous, staying with one mate for life.

Barn owls live around the world, and up to 46 different races have been described with the largest in North America weighing twice as much as the smallest in the Galapagos Islands.

Since they are pretty strictly nocturnal and have low populations in Iowa, you might not have seen one before. You may never have heard one either, although many people wouldn't know it if they do. That's because barn owls don't have any kind of hooting call of a typical owl. Instead, the have a harsh scream that lasts about two seconds and a long hiss that is made when an intruder is getting too close. They also make sounds with their bills and wings to communicate.

Photo of a barn owl calling

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