Uncle's red-headed birds (5)
I believe the answer is:
remus
'uncle's' is the definition.
(I've seen this before)
'red-headed birds' is the wordplay.
'red' becomes 'r' (I've seen this in other clues).
'headed birds' becomes 'emus' (emu is a kind of bird. I am not sure about the 'headed' bit.).
'r'+'emus'='REMUS'
Can you help me to learn more?
(Other definitions for remus that I've seen before include "One responsible for capital" , "doomed wolf-suckling" , "City founder - "uncle" storyteller" , "Avuncular story-teller" , "Uncle character in US folk stories" .)