I have a pair of australian black swans. they successfully mated and hatched four eggs on May 31, 2009. Assuming that either large cat fish or snapping turtles were the culprit, all four cygnets dissappeared within one week of hatching. Our male became very aggressive through out the summer and to our surprise six babies hatched on November 17, 2009. I did not think swans were a multi-brood bird?? should I attempt to put them inside my barn for the cold weather? I live in northeast Ohio and the weather has just started to drop below 30 degrees at night. do you think these cygnets will survive the winter?