I have two chimneys in my house, both lined with a stainless steel chimney liner. From time to time a bird comes down the tube and flies into the wood burner at the bottom, this is not a problem (so long as the fire’s not lit!), I just open the windows in the room and open the wood burner and off goes the slightly puzzled bird.
The other day I woke up to hear noises to indicate that this had happened. I went downstairs, but could see no bird, so I pulled down the flue that covers most of the tube. After an hour or so I could hear the noises increasing, and out popped a Tawny Owl (Une chouette, which incidentally also means smart or great).
The owl was very sleepy (this being day time for humans and so night time for owls, I presume) and did not want to fly away.
After leaving it there for most of the day, I decided that I needed to move it, so donned some thick gloves and put it in the wood shed. I thought that it would fly away during the night, but the following day it was still there, bearly moving. Oh dear, it was surely suffering from shock, my daughter wanted me to find a dead mouse to feed it, but not have too many dead mice in stock, I left it for another night. Happily it flew during the night and now I can hear it twit-t wooing in the oak tree in front of the house each night. I like happy endings!