4 hens, going to 60

I understand the desire to get going on the egg production with mature hens, but they'll be harder, but not impossible, to integrate than baby chicks. But baby chicks raised right in with the existing flock of adults would be, by far, the easiest way to integrate.

What's your geographic location? Climate? Filling out your profile would be helpful.

Many of us brood our chicks from the start right in the run or coop in a safe pen so the adults can see the chicks are part of the flock from the get-go.You do not need to wait until they're almost to the egg laying stage to integrate. I let the chicks begin mingling with the flock at age three weeks. By then, they've been observing the behavior of the adults and even started to get acquainted, so they understand the dangers and will be very adept at evading them.


The key is plenty of space and a safe pen to run back to when things get rough for them. 5x7 inch holes are cut into the safe pen so the chicks can fit but not the adults. This accommodates the chick to age three months. Food and water is inside the safe pen so the small ones don't have to compete for these essentials. By age five or six weeks, I move the chicks into the coop to roost with the adults.

Introducing adults to the flock is a bit touchier since chickens consider strange chickens outsiders and want to drive them away. You begin by keeping the new chickens penned separately within view of the existing flock, gradually putting a few together at a time until they all establish relationships. The more chickens, the longer this process takes because each will relate in some fashion to every other, sorting out their social order over time and trial.

I see no reason why you can't integrate adults at the same time as raise chicks alongside the two flocks as they all work on becoming acquainted. I think a ratio of one rooster to twenty hens would be adequate.

What is your climate/location?

Not sure if you've fully researched quarantine.....
.....these extremes may not be necessary for you r plans, but worth a read anyway.
BYC Medical Quarantine Article
Poultry Biosecurity
BYC 'medical quarantine' search


Here's a great way to integrate chicks to older birds:
https://www.backyardchickens.com/t/1069595/introducing-chicks-to-adults#post_16276224

Very interesting response Azygous. I certainly could separate the 10x14 coops to accommodate the adult hens/chicks intro. I like that approach as the chicks would learn from the adults sooner than being by themselves until they reached the pullet age. Since the chicks would be vaccinated, I take it I would not have to worry about my adult hens passing anything to them right? My flock looks healthy and is laying well. I will quarantine any new adults of course.

Could you please explain in more details how I could work out the two groups of adult hens and the chicks as mentioned in your last paragraph? I am new a this, so the more details, the better.

Thanks

Thanks for the links Azygous. I will check it out.
My quarantine plan is two separate encloses, of course, on each side of our house (so nice physical barrier), using different boots and an overall for the new girls to wear over my clothes. I will, as advised in that thread, handle my hens first then tend to the new ladies.

Ha! didn't see azygous' post when I linked.

Introducing new adults to a flock of existing adults is a matter of allowing them all to gradually establish a relationship with each other. Unlike us humans who tend to ignore any strangers over around 100, chickens, on the other hand, will relate in some way to every other chicken, and they're all different relationships due to all the different personalities and temperaments among chickens.

What I would do in your situation is to have the new and old side by side for about a week, allowing interaction through the fence separating the two groups. Watch the interactions during this period and, after a week, select some from the original group who seem not to be making aggressive overtures through the fence toward the ones on the other side. Begin by introducing the mild mannered hens from the home group into the pen with the newbies. There may be brief altercations that should resolve quickly. Next day, select a few more sweet hens from the home group and place them with the newbies. Next day, do the same.

When everyone in the new group is behaving well, then try opening up the barrier to the two groups. This is when you may have some intense confrontations, but they should resolve themselves quickly. Don't interfere unless a conflict goes on for more than a couple minutes. The idea is that the mild mannered original group hens will fortify the new group and create a new social order where the belligerent ones from the original group will be the minority. The new group, by this time, will know these individuals and will evade them.

Meanwhile, you have a chick safe pen where the chicks are being brooded in view of all of this activity, learning from it as they develop. Blooie has a wonderful article on how to brood chicks outdoors in any temperature. Maybe she'll be along pretty soon and link to it. I've got to go finish shoveling my 900 foot long driveway of the recent snow now.

Dang! I know it's beautiful there and everything, but I'll take miserable days of rain any day. All you need is a good bar of chocolate to fight the gloomy days blues...and good rain gear. Way easier

Thanks for all the detailed info. Much appreciated.

Azygous, I like and will apply the intro method you suggested. Just one last question, your scenario is for less newbies than old timers. In my case I have 4 hens and a rooster and plan to introduce 10-12 new ladies. How would the progressive intro work then? Should I just wait until half of the newbies are befriending the oldies and put them in the pen with the oldies?

Yes, because the newbies will be the majority, and chickens are aware of numbers. The original flock members that have bonded with the newbies will fortify the group and aid in them being accepted into the flock. By the time the flock is all mingling together, I wouldn't expect more than an isolated, very brief conflict, quickly resolved.

Thanks Azygous. I'll do that.Good advice and very helpful.