A petrel's unorthodox way of catching fish (3,4)

I believe the answer is:

eel trap

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'way of catching fish' is the definition.
I know nothing about this answer so I can't tell whether this works.

'a petrel's unorthodox' is the wordplay.
'unorthodox' is an anagram indicator.
'a'+'petrel'='apetrel'
'apetrel' is an anagram of 'EEL TRAP'.

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

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