We've had peafowl and chickens together since 2009. But they free range. Our peas are very protective of the hens and chicks, and they will break up fights among the chickens or protect one who is being picked on by the others, or is alone.. Yes, occasionally they might decide they don't like one or two of the chickens, but it has not been a big deal for us. We do deworm very regularly, but again it is no big deal. We are not breeding anything to sell, we have basically a closed flock, and they all get along pretty much just fine. I can see why a peacock might chase strange birds away, especially during breeding season. ,