My last shot at this - pretty much sure by now!

[drumstick diva]

I also agree with Jed Jackson

 

[The Moonshiner]

All chickens go through chicken puberty at 12 weeks,

I don't think that's true. I'm sure different breeds as well as different individual birds mature at different rates.
I have leghorns that mature fairly early and I was raising orpingtons that seemed like they took twice as long to mature.
Anyways speaking of puberty and since you estimate them to be around 5 months old are any of these birds breeding?
If so is the black on top or bottom?
The behavior was concerning but maybe not so much now that everyone is saying its a "jersey" giant.
I saw about a half an episode of jersey shore and seems jersey girls are all hateful b!tches. I think that explains her attitude problem.

 

[ASD Dad]

Well I have had the Jersey and the laced Wyandotte in training since reading the various posts in here and so far it has helped! The bird doesnt bother me, the wife or kids now. We all walk in confidently and make sure to claim our space. If any of our cockerels show any signs of wanting to be dominant we go after them and do the tail taps with a long switch. Nothing hard at all, a slight tap has then flapping away rapidly! If we turn our backs and they want to sneak or close in we just have to turn around and face them and they freeze.

Only issue I can see is if we need to catch one of them now! They give us a lot of space.

I am still not 100% convince the Jersey is a cockerel, I still see none of the feathers that would point to a boy. It definitely attacked my father-in-law so I am happy to get things under control now.

 

[getaclue]

When they move out of your way, every time you get near them, for a couple weeks, sprinkle some treats not too close, but near you. Stand there, and let them approach slowly to get their treats. Continue with your training, but at this point, they don't need to keep as much distance. They do need to move out of your way though. In a couple days, repeat with the treats. Continue for a couple weeks. Now, you and the rooster(s) should be comfortable in more close proximity, without incident. Now you can easily catch them with a fish net, or a chicken hook.

 

[KikiLeigh02]

I have 2 Jersey Giants that hatched December 1, 2017. One of them finally laid her first egg today, the other one still has barely any comb or wattle. Mine are really calm & friendly, but I haven't let them watch any reality TV. Hopefully your is a pullet that will be laying soon. Glad that it has had an attitude adjustment!

 

[ASD Dad]

Hey all, I wanted to update everyone that chimed in. The Black Jersey is a girl! She is laying eggs.

We now have 3 laying eggs - The Jersey, our other Cochin and one other we are not sure what the breed is honestly... We get 3 a day from those girls. Still have two roosters in the flock - the Cochin and Wyandotte. They get along fine, the Cochin is so laid back he doesnt really care to do much of anything other than hang out. The Wyandotte crows like crazy and is trying to mate a lot lately.

We have a group of Easter Eggers that we hope will be laying soon. They should be 6 months old next month.

 

[getaclue]

Congratulations!