There’s no set method that allows you to drop a new hen into your lot and have everything go peacefully. It’s the nature of chickens to develop a pecking order. There’s understood body language that ranges from mildly threatening head-darts to more aggressive chest bumps. Hens on the bottom will scurry about, and give the top-ranked hens room. Once in awhile, a chicken reasserts her place with a dramatic gesture. The worst is when a hen pins another one down and viciously pecks at her head. Intervene if you see this behavior! On the whole, though, life in a flock should be peaceful. All of this is upset when another hen is added to the mix.
Each chicken will have a different response to the newcomer. Some breeds are easy going, and some won’t tolerate the intrusion. Some large chickens won’t put up with bantams in a flock. And everyone has issues with pouffy-headed chickens like Polish. That said, I have a mixed flock of small and standard birds, Polish Crested, plain brown and speckled that get along fine. (I also have a separate flock of bullies that won’t accept any newcomers – check the HenBlog archives under “bullies” and you’ll find posts about that saga.)
Always isolate the new bird for a week to make sure that they don’t have an obvious respiratory disease. Check for lice and mites and treat if necessary. When ready to add the new hen, lock the flock out of the coop and let the new hen in. She needs to know where the food, water and roosts are. Next, if possible, let the flock out to free-range. Let the new hen into the run. They’ll meet and greet through the chicken wire. There might be chest-thumping and comb pecking, but the drama should soon settle down. With lots of space establishing the pecking order becomes more a running than a pecking game. If it doesn’t, do this introduction several days in a row until it does.
Once the hens have met and can free-range together, you can move the new hen into the coop. Do this at night. When they are asleep, put the new hen on the roost with the others. When everyone wakes up, they just might say, “do we remember you? If you’re here in the morning, you must have been here all along.” I’ve introduced several hens this way with no problems. But not always. That’s why it’s good to have a large coop, because the picked-on hen can get away from the aggressors.
For the first week, keep an eye on your new hen. Make sure she’s not being bloodied by aggressive pecking. Make sure she has access to the food and water. Pick her up and feel her crop – it should be full if she’s eating. Take some time to feed her out of your hand. A tame chicken always fits in better and is easier to care for.