Mechanical bird? (5)

I believe the answer is:

crane

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'bird?' is the definition.
(crane is a kind of bird)

I cannot understand how the rest of the clue works.

(Other definitions for crane that I've seen before include "Large long-legged bird" , "Lifter; bird" , "Tall wading bird can lift heavy loads" , "Bird; dockside machine" , "To do it could mean a long stretch" .)

I've seen this clue in the Evening Standard.

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