Tiny swimmer: little perch? (7)

I believe the answer is:

tadpole

'tiny swimmer' is the definition.

'little perch?' is the wordplay.
'little' becomes 'tad'.
'perch?' becomes 'pole' ('pole' can be a synonym of 'perch').
'tad'+'pole'='TADPOLE'

(Other definitions for tadpole that I've seen before include "Legless creature" , "Frog in formation" , "Aquatic larva of frog or toad" , "Baby frog" , "To plead for tiny frog" .)

I've seen this clue in The Times.

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