Chicks become growers

I'm not sure at what age a chick is defined as a grower but as the first hatch are now over 7 weeks old, fully feathered, off heat and independent I guess they are now growers. A few of the cockerels have even attempted crowing, impressive at such a young age despite sounding more like a squeaky wheel than king of the roost.

I am very tempted to allow them more freedom, their pen is becoming a little small, but with a sparrowhawk sitting on the fence posts just waiting for an opportunity to swoop I am reluctant to do so quite yet.

Photo: Growers at 7+ weeks
(click on image to enlarge)