Dear Beach Bird:
Why don’t birds fall down when they fall asleep on a tree branch or telephone wire?
From Sam, age 13, Egg Harbor
It’s pretty amazing how us birds manage to hold on to tree branches, telephone wires, and other places that seem impossible to hold onto – and manage to stay there, even in wind and rain! So what happens when we fall asleep?
The reason we don’t fall down from where we’re perched while we sleep has to do with the way our legs work – they’re not at all the same as human legs. A bird’s talon works a bit like a pulley – when the leg bends, the foot closes automatically, without the bird having to think about it. This grip can’t be released until the bird straightens its legs again. So, instead of wasting energy holding our muscles tightly – the way a human would if he/she were hanging from a branch by his/her arms – we can just bend our legs, lock our talons in place, and focus instead on getting some much-needed shut-eye.
The NJ Beach Bird