Barred Owl
© CorbisA barred owl.
In the past month, four runners have been attacked by owls in separate incidents, Runner's World magazine notes.

Two of the attacks occurred near Washington, D.C., one in England, and one in Vancouver. Two happened at dusk, and two in early morning, by different species of owls. No one was seriously injured, but the 17-year-old British boy was knocked off his feet.

Four attacks doesn't make a trend, or even a trendlet, but it puzzles Rob Bierregaard of the University of North Carolina at Charlotte, where he studies suburban barred owls, nonetheless -- especially because such behavior would usually be associated with spring, when owls are nesting.

"Barred owls are so used to humans that they've pretty much lost all fear of them. But I can't stretch that to explain why an owl would pop a jogger on the back of the head," he told The Washington Post. "The only thing I can come up with is these are playful young."

If a runner accidentally disrupted a nest or came too close to a young owl, the attack would make more sense, said Bierregaard, who wears safety glasses and a lacrosse helmet when he works with owls.

Other experts suggested that the owls may have been birds that people had previously attempted to rescue, and therefore weren't behaving as they naturally would in the wild.

David Johnson, director of the Global Owl Project, told a natural resource management specialist that sometime people take baby owls home in attempt to help them, but later let them loose, victim Stuart Kern wrote in The Washington Post.

The D.C. attacks appeared to have been by barred owls while the England attack was likely an eagle owl. The species wasn't reported in the Vancouver case. In the past, runners have reported attacked by great horned owls as well.