I have 6 ducks, and one of my female ducks gets on top of my other female and holds her by her neck. They’re all only about 4 months old. Well today i had let them play in some water inside (they live in my garage because we haven’t gotten to build them a coop outside yet since all the snow) and she was holding my one duck under water by her neck. Can someone help me out with why she’s doing this?