Small bird — horse pursued by it around area (4,3)
I believe the answer is:
coal tit
'small bird' is the definition.
'coal tit' can be an answer for 'bird' (I've seen this before). I am not sure about the 'small' bit.
'horse pursued by it around area' is the wordplay.
'horse' becomes 'colt' (I've seen this before).
'pursued by' means one lot of letters go next to another.
'around' means one lot of letters goes inside another.
'area' becomes 'a' (maths abbreviation).
'colt'+'it'='coltit'
'coltit' placed around 'a' is 'COAL-TIT'.
Can you help me to learn more?
(Other definitions for coal tit that I've seen before include "Black-headed small European songbird" , "Little bird" , "singer" , "Flyer" , "Bird producing notes" .)