Neighbor had 3 swans and 1 flew in to our canal and hasn't left. 3 months now. We've all been feeding her. Now she is pulling out feathers and seems to be picking on herself profusely. Is she sick and should she go back to the other swans. They had the other 2 swans wings clipped and don't seem interested in trying to catch her to put her back in their pond. What if anything can we / should do.