How do you know when they are too cold?

[ChickenMama18]

We had our week and a half babies out in the yard with the older babies. It was partly cloudy...but the sun was out where they were and it was pretty warm. As the day progressed the clouds came in. I went to check on them and they were pecking around and peeping. It was probably around 60 degrees without the sun. So, I brought them in...but they didn't seem cold. They weren't huddling together or shivering. Should I go by temperature outside or their behavior? I know birds can mask when they are sick...would they do the same if they were cold? What is the down side if they do get a little cold?

 

[danielle82]

Usually by behavior. And I may be crazy, but I feel their legs too.
I start mine outside a little at a time and work my way up, even if its cool out, as long as there is direct sunlight they do real well.

 

[fancbrd4me02]

The will huddle together and hunch thier shoulders up and peep loudly.