I picked up 10 newly hatched chicks last night at an auction, I have a broody thats been sitting nearly 2 months. I slipped all 10 under her last night, she didnt push them away or act aggressive in any way. This morning the chicks are seemingly ready to explore with the big girls, and momma is still sitting pretty tight on the nest. I found one of the littles outside of the coop in the run with the big hens. I took it and put it back, I dont know if this is successful or not, no one is acting aggressive towards them, but no one is really watching out for them either, they are going under the momma as they want, but also straying away.....whats the deal?
A hen may need a bit of time to transition from 'setting mode' to 'mama mode'. Some make the transition quickly but not always. A hen sitting on eggs feels the movement of the chicks in the eggs the day before hatching and hears them begin to cheap after internal pip....these cues allow them to start transitioning. When a hen doesn't get the natural cues it just may take longer to adapt to the sudden arrival of fuzz balls.
Patience and observation are key...sounds like your flock is tolerating the fuzzy invaders well, which is good. You can make a scrambled egg and chop it super fine and put it in a low sided dish and place it near the broody and see if she calls chicks to it. Just watch for any signs of aggressive behavior so you can intervene and put the chick back under the hen so she gets used to feeling and hearing them a bit more before she sees them.
Chicks get used to heat lights very quickly, so depending on how old they were (24 hrs or 48 hrs?) They may be more willing to roam a bit. It will be an adjustment for them also.