Quality of bird captivates artist (5)
I believe the answer is:
trait
'quality' is the definition.
(thesaurus)
'bird captivates artist' is the wordplay.
'bird' becomes 'tit' (I've seen this before**).
'captivates' indicates putting letters inside.
'artist' becomes 'ra' (Royal Academician, member of Royal Academy of Arts).
'tit' placed around 'ra' is 'TRAIT'.
'of' is the link.
(Other definitions for trait that I've seen before include "Decorative band" , "Quirk" , "A characteristic of straitened kind" , "Distinguishing feature" , "Idiosyncrasy" .)