From International Owl Center

Did you know that many species of owls like to sit in the morning sun? Barred Owls, Great Horned Owls and Eastern Screech-Owls (and likely other species) do this. For screech-owls in winter, this also helps warm them up in the morning. It may also help convert the oils that they smear on their feathers from their uropygial (preen) gland into vitamin D, which is ingested the next time they preen. Here’s Pierce the Barred Owl soaking up some sun this morning before work.