Sleeping Great Blue Heron

We came upon this Sleeping Great Blue Heron along the Wildlife Drive at the Edwin B. Forsythe National Wildlife Refuge. It seemed to be very content to sleep, but as I was photographing the Heron it starting moving and then looked more annoyed as if I was bothering his sleep. Probably just my take on it, but it had a very severe look as it was watching me. He was also very balanced standing on one leg. Either way I thought it was interesting photo.