He's after a bird for contributions (6)
I believe the answer is:
tithes
'for contributions' is the definition.
(tithe is a kind of contribution)
'he's after a bird' is the wordplay.
'after' is a charade indicator (letters next to each other).
'a bird' becomes 'tit' (tit is a kind of bird).
'hes' after 'tit' is 'TITHES'.
(Other definitions for tithes that I've seen before include "Church taxes" , "Tenths of income once paid to church" , "Tenth parts, levied by some churches" , "Levies of one tenth" , "Tenth parts, levied by a church perhaps" .)