Flier succeeded with wangle — not half! (4)
I believe the answer is:
swan
'flier' is the definition.
(swan is a kind of birdanimal)
'succeeded with wangle not half' is the wordplay.
'succeeded' becomes 's' (genealogical abbreviation).
'with' says to put letters next to each other.
'not half' means to take half the letters.
'wangle' halved is 'wan'.
's'+'wan'='SWAN'
(Other definitions for swan that I've seen before include "Long-necked water bird" , "Royal bird" , "Large waterbird" , "Cob - pen" , "Large water bird" .)