I've got a female rouen expressing hostile behavior. She's tried to drown a chicken in the waterer, pulled feathers out of other birds, and bites at fingers. This behavior just started about four days ago, and I'm very much not willing to allow it to go on. It's not like I have a shortage of female ducks around here. I'm estimating her current weight at about 6 pounds. She's not my biggest duck, but she's certainly not the smallest either.