If you touch a baby bird, will its mother reject it?

No.Most birds have little or no sense of smell and cannot detect human scent on their chicks, according to Texas Parks and Wildlife. A chick put back in its nest won't be rejected for smelling of people, though it's still best to leave fledglings alone.

What's actually true

Touching a chick won't make its parents reject it. Many of us were told never to touch a baby bird because the parents would smell us and abandon it. Texas Parks and Wildlife says most birds have little or no sense of smell and cannot detect human scent on their chicks. It's still best to leave fledglings where they are: parents are usually nearby.

Takeaway: Most birds can't smell human scent on chicks. Leave them anyway: the parents are usually close.

Why people believe it

It's a useful rule dressed up as a fact. Parents and teachers wanted children to leave baby birds alone, and 'the mother will reject it' is more persuasive than 'please don't'. Some mammals with keen noses really can react to handled young, which makes the bird version sound plausible. The advice holds up; the reason behind it doesn't.

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