This is a really long shot but worth a try. Many, many years ago I read a novel about a man who lived in a remote place where there was a group of sandhill cranes (I think that was the species). Amongst them was a single rare crane of another species. He knew that because the single crane was so rare he ought to inform the authorities but he was reluctant to do so because the bird seemed quite content with the others. I'd love to read this book again but I can't remember who the author was. Anyone?
