I was hoping today to cut a cleaning hatch in the bottom of a nesting barrel at my friend's farm and also clean out and add some hardwood chips. Regrettably I was told by my friend that an owl is back in the box-she sees it fly out during the evening. Have I left it too late to clean out the barrel and should I now leave it until next autumn? My friend insists that she does not want a new nesting box and the old one must remain in situ. Unfortunately it is half full of excrement and an owlet fell out last summer. What is best to do?