To most the idea of a pen or yard full of peacocks sounds like a beautiful sight. To the peacock, it sounds like trouble. Durring the breeding season, the male peafowl forms a lek, which is an area in which he will display to attract peahens. The peacock will defend this area from other peacocks wanting to take over his territory. Peacocks will fight each other when they are penned together, and they will fight each other when they are free-ranging together. I will explain to you the fighting behavior of the peacock and how you can lessen the fighting between males or prevent it.
When you pen at least two peacocks together in an aviary with peahens, they are bound to fight come breeding season. After keeping 3 mature peacocks in a pen with 4 mature peahens I have seen my share of fighting. There is a pecking order amongst peafowl, and the goal of a peacock is to move up the pecking order by fighting the alpha peacock and winning and thus getting better breeding rights. The alpha peacock keeps the other peacocks in check. If they try to mate with a peahen, he will run up and attack them or if they are displaying and he does not want them to display, he will kick them to make them stop. Then, all of a sudden a fight might start. Sometimes all that happens is the alpha peacock chases another peacock around the pen, kicking at him when he gets the chance. Also, he will try and corner the offending male and peck at his face. But, sometimes it turns into a real fight when the peacock does not run away, but stands to challenge the alpha male or any male for that matter. The two peacocks will circle each other, turning sideways to appear bigger. Then, without warning they will jump into the air kicking at each other with their spurs. In either case, both males will likely end up panting like crazy and they will go off in seperate directions to cool down. To prevent penned peacocks fighting you have several options. For one you could have a pen full of peacocks and no peahens in the pen - people say this helps prevent fighting, or at least serious fighting, but I haven't tried it. Another option is to do what I do and provide an area for the lower ranking peacock to run to and hide. I give my peacock Peep a dog box to jump into and hide since he is not good at fighting. This helps prevent him from getting too picked on since the dog box only has room for him. Finally, there is the popular option of just keeping one peacock per pen. That is my goal is to eventually get my setup to that point. I just don't have enough pens for that yet. Having one peacock per pen helps you have less confusing breeding results and records, and it probably makes the peacock much happier to know that he doesn't have to deffend his territory from another male. Sometimes you have to worry about fence fighting, which is when a peacock in a next door pen decides to fight the peacock next door. They will try kicking at each other through the fence. In some cases this can be so distracting that one or both pens will have bad breeding results because the peacock is too occupied with fighting to breed the hens. The solution to this problem is a sight barrier. Most use sheet metal for sight barriers. Some people use temporary sight barriers that go up in the breeding season and come down for the rest of the year. Materials for a temporary sight barrier would be something like shade cloth or tarps.
Penned peacocks are more confined so it would seem that free-ranging several peacocks and peahens together would make fighting almost non existant. Actually, it appears that even with a lot of room, the males will still find each other and fight for the right to be alpha. You could try penning up all but one peacock durring the breeding season, but that is no fun! I haven't done much free-ranging, but I know people who do. Mainly, there is not much you can do for the peacocks that are fighting. As long as they have places where they can run off and hide that is good. Just like most male animals, peacocks have an instinct to fight other males for the right to breed. The alpha peacock usually gets to breed more. So just keep an eye on those boys and make sure they don't seriously hurt each other. Usually though, the fighting is nothing really serious and if you get a peacock that seems mean, you can keep him penned and not let him free range.
In conclusion peacocks are naturally driven to fight each other durring the breeding season. To keep your peacocks safe you need to keep an eye on them and provide them with areas to escape to. Keeping one peacock per pen or keeping several together is up to you, and both situations can work really well. It is up to you to decide what to do, but for penning keeping one male per pen seems to work well and for free-ranging it seems to matter less as long as you have more peahens than peacocks just incase.