Hello!
I would say that taking the lone chicken is not at all a bad idea and will definitely benefit her and even you.
Introducing is relatively easy, though it is a process. Since your existing flock is already small, adding her shouldn’t be a problem.
There isn’t one specific way to introduce new flock members. What I am sharing is only what I usually do, but others may have different ideas or tips.
First, it is recommended that you quarantine any new bird for a while, usually at least two weeks, to ensure that it doesn’t bring any diseases, parasites, or other things over to your birds. Then you should keep her in a cage that your other hens can see and be around (inside the coop or run), but can’t get into or be able to peck at or hurt the single chicken inside. Keep her in there for about a week (or longer if you feel that it is needed) so that they can all get used to each other and no one feels like there’s any intruder. At this point you can then let her out to be with the others but make sure to keep a close eye on them in case they don’t get along. Typically, the larger the run, the less you have to be concerned for everyone’s safety because they should all have a place to escape each other’s pecking. A little scuffling and a few pecks is normal. They will have to establish a pecking order among themselves and this is how they express dominance. It’s nothing to be worried about.
That being said, it can be slightly dangerous for a newcomer if the others are incessantly chasing or pecking at her, or if she doesn’t have anywhere to hide. The key is to watch the flock and observe how they interact with each other, and to intervene only if there is a serious issue. Most likely everything will be fine, because like I said before, a small flock is safer to add new birds into and it is natural for chickens to want to be dominant over one another.
Others may have more advice, but I hope this helps at least a little!
