Italy is protective of black wading bird (4)
I believe the answer is:
ibis
'wading bird' is the definition.
(ibis is a kind of wading bird)
'italy is protective of black' is the wordplay.
'italy' becomes 'i'.
'protective of' is an insertion indicator.
'black' becomes 'b' (as in pencil classifications).
'i'+'is'='iis'
'iis' placed around 'b' is 'IBIS'.
(Other definitions for ibis that I've seen before include "Retreat" , "Large wading bird" , "Wading bird of warm regions" , "Sacred Egyptian bird" , "Wading bird sacred to the Egyptians" .)