I have had Guineas about a year and a half. I now have a flock of 31. I love watching them, their eating up the bugs, etc. except I cannot let any of my Buckeye cockerels/ roosters out with their hens because the Guineas gang up on the roosters. They chase the hens sometimes but aren't overly aggressive to them. I do have one Game-like Rooster I can let out ( I guess he hits hard enough to discourage the Guineas so they leave him alone, but I don't want him out the same time as my Buckeye hens). By and large, I have my dogs and donkey so my chickens, geese & guineas are able to free range and not have to worry about predators. I want to be able to free range my roosters in turn with their hens and not have them attacked. This has has happened repeatedly. The Guineas gang up on the rooster or cockerel. Fortunately, I have been out there and saved the Buckeye male from being killed. My hens just run if attacked but the Guineas really zero in on a cockerel or rooster. The only other chicken male they have not tried to kill was one that was raised outside from a two week old chick (and he just learned to run and stay far away from them) -- I am running an ad to sell my adult Guineas and I did put in there, that I would not sell them as singles but in groups of at least 6 -- they should go in some kind of group to have some coherency. I bet I get calls from all kinds of people begging for one or two. A friend wants my lavender ones which I promised she could have.