We have had a female swan on our lake for about 8 years. We had her brother in the beginning but he got out and was killed on the road. We understand siblings don't mate. Now we have just put a young male swan--under a year old--- in the lake. She imediately attacked him pulling out feathers from the bone. We then separated them by putting a net in the pond between them. She has tried constantly to get by the net. The male swan who has the greater part of the pond has not left her side on the other side of the net. They have been in the water over 24 hours. This morning they seemed to be conducting a form of communication. She would do something and he would imitate what she had done. We have been told this might be courtship activity. Our question is can we put them back together? Of course our greatest fear is that she might kill him. Is there a period time we should keep them apart before trying to put them back together?