Creatures held in coop or cup in Estonia (10)

I believe the answer is:

porcupines

'creatures' is the definition.
(porcupine is a kind of creature)

'held in coop or cup in estonia' is the wordplay.
'held in' indicates a hidden word.
'PORCUPINES' is hidden within 'coop or cup in estonia'.

I've seen this clue in the Sydney Morning Herald.

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