Well i am new to chickens, had 3 ex-battery since august, but i think i've been a bit slow realising that the chickens are meant to roost at night! That is on the perch! Mine sleep in the nesting box! I have seen them on the perch, but less now its cold, they are always snuggled up together in the nest box. It is a pain that i'm always trying to keep it clean, i hate them lying in their mess! But does it really matter where they sleep? if so, how do i change it?