Bird left Noah's boat (4)

I believe the answer is:

lark

'bird' is the definition.
(lark is a kind of bird)

'left noah's boat' is the wordplay.
'left' becomes 'l' (common abbreviation).
'noah's boat' becomes 'ark' (I've seen this in another clue).
'l'+'ark'='LARK'

(Other definitions for lark that I've seen before include "Mischievous activity" , "Play about" , "Songbird; escapade" , "Bit of fun - early-rising bird?" , "Bird - caper" .)

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

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