I have 4 adult ducks, 3 female, 1 drake, 10 week old ducklings, 3 month old ducklings. They are all free range and live on the dam where they have a house floating on the middle of the dam for their safety. One of the adult females has become very aggressive to her daughter who has batch of ducklings about a week old. At feeding time she constantly bites at the ducklings and pushes them under the water or chases them and when the mother steps in to defend them she attacks her also. The aggressive female also has 3 ducklings that are about a month old but she neglected them and they tend to swim with the younger ducklings and their Mother as she does look after them very well. Not sure what to do or will this pass naturally. Cheers.