Flier making delivery? (5)
I believe the answer is:
stork
I believe this clue is a double definition.
'flier' is the first definition.
(stork is a kind of birdanimal)
'delivery?' is the second definition.
(thesaurus)
'making' is the link.
(Other definitions for stork that I've seen before include "Long-legged bird" , "Baby-carrying bird?" , "The baby bird, so to speak" , "Mythological baby-bringer" , "Large wading bird" .)