Bird food left on loose stones (7,3)
I believe the answer is:
screech owl
'bird' is the definition.
(screech owl is a type of owl)
'food left on loose stones' is the wordplay.
'food' becomes 'chow' (chow can informally mean food).
'left' becomes 'l' (common abbreviation).
'on' says to put letters next to each other.
'loose stones' becomes 'scree'.
'chow'+'l'='chowl'
'chowl' after 'scree' is 'SCREECH-OWL'.
(Other definitions for screech owl that I've seen before include "Eg, Tyto alba; howls recce (anag.)" , "Bird of prey" .)