Broodies, and babies, and ranging! OH MY!

[The Wild Hen]

Happy Wednesday. I have two broody mamas that went broody in December/January (oddly enough in freezing cold Iowa) and I finally let them sit. Two weeks ago tomorrow each hen hatched five babies a piece (one went MIA and one didn't hatch). So I penned off part of the coop with dog crate fencing, placed an old window between the two sides, chicken wire over the top to keep others out and have two little maternity wards set up among the rest of the flock. They have each a chick feeder and waterer and I've had a lamp on them only to keep the little waterers open in the cold temps. They can see each other through the window, each others babies, the entire rest of the flock, etc. The flock can see them. Both mamas are doing well as are the ten little chickies. They jump on their backs and hang on them it's pretty fun to watch. Okay, my actual QUESTION is this. When is it okay to let them out of the maternity ward and be with the others? To free range and such? Keep in mind, it's IOWA, getting a couple 40 degree days but still lots of snow on the ground. My chickens free range all day and come and go into the coop as they please. I think my mamas might be getting a little cooped up pun intended. I know I would if I had five kids jumping on my back and constantly chirping at me. I also have four ducks that live with the chickens too. My setup is a large hanging feeder, a large, open heated water bowl (chickens and ducks share), and pvc free grit and oyster shell. Now the chicks would not be able to access any of that but if I let them out do you think the mother would bring them back into their pen? My gut tells me I need to wait until they are older but I'd really love some advice. First time around with broody hens and hatching and such. TIA

 

[ChickenCanoe]

In my opinion, the sooner you put the new families with their original flock the better.
At this age, the mothers will protect the chicks from the other flock members. By the time they are weaned, the chicks will have been accepted as flock members. If you wait till the hens wean them, the chicks may be brutalized because they are new.
Don't worry about the temperature. If the chicks get chilled, they'll run back to mom and she'll plunk down on them long enough for them to warm up.