Chickens in the wild find shelter high up where fewer predators can see them. This usually means tree branches but could also be in shrubs or bushes, or a nest if a hen is brooding her eggs. Providing roosting bars in your coop gives chickens the option of sleeping higher up for increased security. This is a good idea, especially in winter when nights are longer.
In general, a chicken will sleep through the night as long as there are no loud noises or intruders. They will wake up when the sun rises.
When a chicken goes to sleep, they will huddle together with their flock to feel safe and warm. Chickens with higher ranks in the pecking order will sleep at the top and those lower down will roost below them.
It is very common to see a chicken with one eye open while they are sleeping. This is due to a remarkable survival strategy; when you sleep with one eye open, the other half of your brain stays awake and alert to any potential threats. When the eye is closed for REM sleep, this is when dreaming happens.
A chicken’s sleep is vitally important to their health and wellbeing. It helps their immune system to recover and prepare for the day ahead. Without enough sleep, chickens can become very sick. This is why it is important to make sure your chickens have a clean, comfortable place to roost each night.