Wasn't emu originally a flier? (4,4)

I believe the answer is:

mute swan

'a flier?' is the definition.
(mute swan is a kind of birdanimal)

'wasn't emu originally' is the wordplay.
'originally' is an anagram indicator.
'wasnt'+'emu'='wasntemu'
'wasntemu' anagrammed gives 'MUTE SWAN'.

(Other definitions for mute swan that I've seen before include "Common waterbird" , "creature" .)

I've seen this clue in The Times.

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