Parrot beginning to mimic a crow's cry (5)
I believe the answer is:
macaw
'parrot' is the definition.
(macaw is a kind of parrot)
'beginning to mimic a crow's cry' is the wordplay.
'beginning to' says to take the initial letters.
'crow's cry' becomes 'caw' (I've seen this before).
The initial letter of 'mimic' is 'm'.
'm'+'a'+'caw'='MACAW'
(Other definitions for macaw that I've seen before include "brilliant winger" , "Tropical parrot" , "colourful flyer" , "Chattering cousin of a cockatoo" , "Type of parrot" .)