Hi, I have three chickens that have only recently been penned in. I am building a larger coop for them and was considering getting a few more chickens. Their current area is about 135 square feet but I am not sure how many birds could stay in the area. Also my birds were born and raised together and have never met another adult chicken. The closest that they have been to meeting other birds was when they were at the store with other chicks, and a stray pheasant that happened to wander in to my yard. I was wondering if there is any special way that I should introduce new birds to them so that they get along?