The 2 black chickens are both roosters, I'm assuming that the one with the head I can't see is a rooster as well. From feathersite it says this about the differences in Black Australorps and Black Jersey Giants:
"Australorps differ from Black Jersey Giants in that the legs of the Jersey Giant...
So that would probably mean that the black ones are about 40 weeks old? By that age they should be laying eggs, could you get pictures of their tail feathers and side? Other crowing roosters can encourage a new cockerel to crow as well, sometimes when you startle or just raise your arm above a...
I don't use an electric fence though I can help with the breeds. Your golden colored pullet is a Buff Orpington, your black chickens (which are probably Black Jersey Giants because you said that they were taller, if not they are probably Black Australorps) and it could just be the picture but I...