I guess I should have expected this.....The ducklings (2 week olds), 1 Rouen m/f?, 1 mallard female were outgrowing their brooder, so I transfered them into an intermediate brooder and thought this might be a good time to put the 1 week olds, 2 mallard females, in with them. they have been together every day outside their brooders and have gotten along fine. Well the Rouen has now become a little aggressive, not only to the little ones, but to his/her brooder mate, and she in turn is being aggressive towards the little ones. It's nothing serious, so far......just pecking and poking over by the food and water and making a huger mess than normal...oh yippee..... I am keeping a close eye on them...but I'm wondering if this is going to be OK. Just establishing pecking order? Could the Rouen be a drake? Is it because he's so much bigger than all of them? I should also mention the chicks, also 2 weeks old, are right next door. They are separated by 1/4" hardware cloth. Again, they have all been together, chicks and ducklings outside brooder every day and just kind of ignored each other. Maybe it's having the chicks next door? Too much stress? The Young and The Restless? OK...now the ducklings are all cuddled up together....siiiiiiighhhhhhh. I guess it's OK?