From what has transpired, we do not think either one of these swans are a female. Females do not chase males, and males usually will not hurt a female. And, therein lies the problem. The younger swan is stronger and feeling his hormones at this time of the year. Either one could get seriously injured or killed if they attack each other. The one swan going into the woods is going to get killed by a predator. You need to have a veterinarian sex the birds to ensure what you think you have is reality. If you have two males, you may need to build a pen (1/2 in water 1/2 on land, feeder inside, enclosed top to bottom so that a predator cannot dig under or climb over the pen to access the swan. Place the young swan in the pen and let the original male go back to his habitat. If you cannot build a pen, then place one in a safe secure shed, garage or barn until you can get the birds sexed. Then, you will need to make a decision to see if you are going to find a good home for the second bird if it turns out to be a male. If it is indeed a female, it will allow everyone to calm down and get the hierarchy back to normalcy. The Regal Swan