Oh yes, those photos are conclusive. That's a cockerel, all right. If he seems aggressive toward the other two, you've likely seen his first, awkward attempts at mating. They grab hold of neck feathers and try to mount. The females (being many weeks away from laying, yet) are not mature and will resist his efforts. That won't stop him from trying again, though. With only two pullets getting all of his attention, it may be rough on them. He'll also be crowing at full volume soon and may already be trying (sounds like a squeaky hinge at first).
If you intend to keep him, they would all benefit from a better male:female ratio. I know 6 wasn't enough for my cockerel (bared all of their backs) and I can't imagine that sort of energy being devoted to two.
If you intend to keep him, they would all benefit from a better male:female ratio. I know 6 wasn't enough for my cockerel (bared all of their backs) and I can't imagine that sort of energy being devoted to two.