Artist capturing male bird that can't fly (4)
I believe the answer is:
rhea
'bird that can't fly' is the definition.
(flightless bird)
'artist capturing male' is the wordplay.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'capturing' means one lot of letters goes inside another.
'male' becomes 'he' (he refers to a man).
'ra' placed around 'he' is 'RHEA'.
(Other definitions for rhea that I've seen before include "South American bird resembling the ostrich" , "China grass" , "Flightless bird from South America" , "Big bird" , "Fast runner" .)