Whenever the adult swan (cob) approaches his juveniles, with his wings arched and head tucked in, they flee from him. Sometimes he chases after them and makes them fly but they only fly sufficient distance to keep out of his reach.This harassment of his juveniles goes on everyday. It seems he is trying to encourage them to fly away. It's a great spectacle. They are magnificent birds, so graceful in the water and so powerful when flapping their wings.