Thanks for your informative answers. I wish I knew all of the answers to the questions you posed, but unfortunately, I am new to the lake. From what I have learned from neighbors, Carl is not a young bird and hasn't been seen with a mate. He is easily recognizable, though, due to an injury to his foot that has healed (as much as possible). His center "toe" appears to have been severed in the middle, so there is basically a hole in the front of the foot and a huge knob in the back of the foot. When Carl walks, his foot "flops," and he doesn't seem to be able to fly as high as other swans, as he doesn't get his foot completely out of the water when he flies. According to neighbors, Carl has been the target of many aggressive swan attacks in the cove and has received human intervention on several occassions. A pair of trumpeters was being horribly nasty last fall, and Carl ran into our yard. My husband and I stood guard at the shoreline until they left so that they woudn't attack him. My husband and I both feed Carl, so he will walk toward either of us when we are in sight. Carl hasn't shown any aggression toward any humans, including a number of different friends who have come to visit. I don't want Carl, or anyone else, to get hurt. Does this additional information lend any insight into Carl's friendliness?
We are only at the lake on weekends, so I don't know what his routine consists of during the week. Usually he isn't in sight when we arrive for the weekend, but he will appear within 10 minutes of my calling him and stays closeby for the remainder of the weekend (until we leave). I think that Carl has worked it out with Bella (I have no idea whether Bella is a male or female), the Polish Mute who has been camping out at my place for the last 6 weeks, as he doesn't chase her away. There is only one other swan that I've seen Carl allow in the cove, whose mate Carl promptly chased away. What I don't know is if this behavior constitutes Carl "liking" that swan. I would love to find a mate for Carl, but I don't know where, or how, to begin~
Again, many thanks!!