I gawk at thresher at sea, a predatory creature (5,5,5)

I believe the answer is:

great white shark

'a predatory creature' is the definition.
(great white sharks are predators)

'i gawk at thresher at sea' is the wordplay.
'at sea' indicates anagramming the letters.
'i'+'gawk'+'at'+'thresher'='igawkatthresher'
'igawkatthresher' with letters rearranged gives 'GREAT WHITE SHARK'.

(Another definition for great white shark that I've seen is " Fish".)

I've seen this clue in The Telegraph.

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