My sister-in-law discovered a rather PO'd Mallard in her fireplace in Wisconsin. She did not have a Plan A or Plan B; I think she tried to grab it and missed. She ended up with sooty duck prints in some rather peculiar places around much of the house during the ensuing chase. She finally opened a window and the duck took advantage of the opportunity to depart. She will still debate the merits of a chimney cap with you, since she was once told that caps keep your fire from drawing!