Do sleeping birds fall off their perch?

Birds often fall asleep while standing on a tree branch or perch. Unlike monkeys, birds do not have a prehensile tail to hold onto the branch. So, why don’t they fall off?

Birds do not fall off their perch – or rarely fall off – while sleeping because their feet and claws automatically grip the branch, twig, or perch. Their claws grip into the wood. 

The gripping, or grabbing, motion is caused by tendons – not muscles. 

Muscles relax when they get tired, which would stop the claws from gripping the perch. 

However, tendons, or sinews, are tough, strong, fibrous tissues that connect the muscles to the bones. Tendons are like a mechanical force that contracts and stretches the muscles, and provide support and stability when the birds are standing on a perch. 

Photographer: Martina Nicolls

Martina Nicolls: SIMILAR BUT DIFFERENT IN THE ANIMAL KINGDOM