So, I have a small flock of waterfowl- 10 Khaki Campbell ducks and 1 Toulouse goose. All are females and have been living together their whole lives. My goose and one duck are from last year's hatch, and I introduced 9 new ducks this spring. Everything has been perfect up to this point. Integration went very smoothly several months ago. The flock has always been very close-knit. They've never given me a moments worry. Until today. Today I found my older duck locked in mortal combat with one of the younger ducks. Initially I thought they were just tussling a little, which is unusual, but not totally unexpected. I rapidly realized that they are trying to kill each other. Feathers are flying, and these 2 girls are trying to rip each others' heads off. I kept breaking them apart, but they would just run off and continue their fight further away. I have resigned myself to just letting them fight it out until whatever their issue is gets resolved. I am just hoping neither one gets hurt very badly. Is this unusual behavior for females? For this flock it is unusual, but I would like some input from others. I am rather at a loss. I have seen my hens squabble a bit, but never the ducks. And the violence they are aiming at each other is far beyond what I have experienced in an established flock before. What gives? Just a little more info- everyone is healthy. They have more room to roam than they could possibly use. Housing is of adequate size although they are never in it except at night. They have access to layer food and water all day. The only change in their environment is I had to put away their pool because it will freeze in this weather we are having, but I did that about a month or more ago. Thanks for any insights.