I have a question about the temperatures with swans. we have a pond with 1 swan who lives there. the swan was brought here to keep the geese out of the pond. He does have his wings clipped so he cant leave to go anywhere. The temperatures have went to -12 over night and his pond is freezing more. it will not fully freeze as we have an aerator installed. He is laying on the ice with his head buried in his back. Is there anything that we should be doing as precaution, as we are going to have negative temps for the next day or so?