How Do Birds Sleep?

Have you ever wondered what happens to birds at night? Such as do birds actually sleep at all and how and where do they do it? If you’ve ever wondered how birds sleep, the answer is more complex than you probably imagine.

So how do birds sleep?

The way that birds sleep will depend upon their species. Many birds roost on perches such as tree branches. They don’t fall off because the muscles in the leg tighten the tendons of the feet firmly around the branch in a vice like grip. This is an automatic reflex that the bird does naturally so to them this is comfortable and safe. Most birds including domestic chickens will sleep soundly in this position.

Not all birds need a perch in a tree to sleep. Some varieties of birds such as waterfowl will sleep by the water’s edge or in the water. Many will find a partially underwater stick or rock or anything they can grip with one foot and sleep on one leg with their heads tucked under their wings.

Other types of bird such as swifts or house martins will cling to any parts of a building that is high up and that they can grip their foot around.

Not all birds sleep at night. The owl is famously nocturnal and this bird will spend the day sleeping up high somewhere on a branch, waking up at dusk when it is time to go out and hunt.

Most birds do not sleep soundly in the way that we humans know it. They are always alert to danger so tend to sleep in short snatches, waking up at the smallest disturbance. Some birds sleep with one eye open as they have the ability to keep half of their brain asleep while the other part is awake and alert to danger. This function is called unihemispheric slow-wave sleep (USWS).

USWS enables birds to even sleep while they are flying. Birds such as swallows that carry out long distance migrations can sleep on the wing which enables them to travel vast distances without stopping to rest.

You might wonder how do birds sleep when the weather is cold but most birds function very well at low temperatures. They have fantastic warmth generating downy feathers under an outer covering which fluff up like a duvet keeping the bird warm and cosy inside. They also tuck their heads under a wing or back feathers and tuck their legs up too under a warm blanket of feathers.