Little Runt (my drake) is almost a year old. He's a Mallard Khaki mix. He has 4 ladies but is obsessed with the one he has been with since hatching. He follows her everywhere she goes. He mates all the ducks but never leaves the ones side. For some reason when one particular duck comes around his girlfriend, Runt chases her and pulls out her feathers. I have tried putting him in time out but it doesn't work. As soon as you let him out he goes right back to chasing her. Any ideas how to stop this behavior? He doesn't chase any of the others.