And about the material they running on, is bare soil okay ? or should I use pine shavings. I don't have pine shavings at the moment but I can easily make with a hand planer . I am afraid they might eat it or the finer particles .
Alternatively could I put them in a "chicken tractor" on my lawn?
Are they with a mother hen?
If not I would keep a heat source with them. I don't know what your area weather and temperature is right now.
Here we are going into winter.