This morning I located the West Seattle barred owlet ("Wollet") for the
first time in a couple of weeks. I was alerted to where he was by his
squealing for food, though could not find an adult nearby. When I got back
home and downloaded my photos to the computer, I was surprised to see that
he was gnawing first on some bark, then on the branch he was sitting on.
(Photos at flickr.com/photos/trileigh -- not great aesthetically, but
informative.)

I'm concerned that he may be overly hungry if he's chewing on wood. Or is
this normal behavior for a well-fed owl? Is there some benefit to his beak
or digestion to gnaw on wood?