We live on a large lake in the midwest, populated by hundreds of homes. There is a single [mute?] swan (with no banding) that has been living on this lake for the past 8 years. Sometimes we see her everyday for two weeks, or we may not see her for 8 months. I have no idea where she goes when the lake it frozen, but she is around in the winter, and I have never seen her fly. She has always been very friendly, swimming to you when you call her, knowing you'll have some type of treat [bread]. She will take food right from your hand. The other day she came around and her beak was flesh colored (not the bright orange color it normally is), and she though she came when I called, she wouldn't come close to me at all - she stayed back, acting odd. She went for the bread in the water, but acted like it was too hard to eat. I am wondering if she is ill. Does a discolored beak and unusual behavior indicate she has a sickness?