CIA leave aviculture to a bird (7)
I believe the answer is:
vulture
'bird' is the definition.
(I know that Vulture is a type of Bird of prey)
'cia leave aviculture' is the wordplay.
'leave' indicates named letters should be taken away.
'aviculture' with 'cia' removed is 'VULTURE'.
'to a' is the link.
(Other definitions for vulture that I've seen before include "Large bird of prey that feeds on dead animals" , "Scavenging bird" , "Large carnivorous bird or a greedy person who exploits others (7)" , "Large bird of prey or predatory person" , "Large bird that lives off carrion" .)