From Jen Marie
A rare combination from years ago. Great horned owls don’t build their own nests; instead, they use a nest that another bird has previously built or a tree cavity. In this case, the owl used a great blue heron nest, and this baby was the last to fledge.
I tried searching for more details, but didn’t really come across much. Just shared another great photo, possibly the same pair of nests, with more inhabitants.
After reading a few threads posted by a few photographers, they all just said it was a huge surprise, but nobody noted any violence one way or the other. The herons are quite dangerous in their own ways.
Without knowing where this was, I don’t even know if I could figure out which bird moved in first and which one said “this is fine” and moved in despite the other being there.