Barred Owls are native to eastern North America, but over the past century they’ve moved across the Great Plains and into the forests of the far West. There, they have effectively colonized the entire range of the Northern Spotted Owl, says Wood, displacing their slightly smaller cousins. “These two species just can’t coexist. They’re too similar ecologically, and it’s the spotted owl that loses because Barred Owls are bigger, more aggressive, and more flexible in what they eat—just all around competitively superior.
