While exploring the woods near his home in Ohio last year, Sam Cox came across a hollow tree he thought looked like the perfect owl nesting site. Although he didn’t find any owl sign, such as pellets or whitewash on the ground around the tree, he was curious about how deep the tree’s crevice ran. He reached his camera into a chest-high hole to snap a photo – and was surprised to discover two sleepy raccoons nestled together within the tree. Raccoons are not true hibernators, but they become inactive for much of winter and may den together in tree hollows to share warmth.