I would guess he is a D'Uccle cross. Did he come from the same place as the hens? If he did, then I would guess he's possibly a D'Uccle/Japanese cross. His legs and feet don't seem to be as heavily feathered as a D'Uccle's nor is his beard as thick and pronounced. He also seems to be missing the vulture hocks you would see on D'Uccles.