Generally my chickens and ducks get along fine and don't pay each other much attention. However recently one of my hens has chasing and grabbing the younger ducklings. This chasing goes on for quite awhile. She will get hold of one of the ducklings by a wing or scruff of the neck and hang on with her beak, all while the little duckling cries for help. This happens when they are out free ranging. Anyone have any experience with this?