No brawl disturbs such a light sleeper (4,3)
I believe the answer is:
barn owl
'a light sleeper' is the definition.
The definition and answer can be both animals as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'no brawl disturbs' is the wordplay.
'disturbs' indicates an anagram (I've seen 'disturbed' mean this (the order of letters is disturbed)).
'no'+'brawl'='nobrawl'
'nobrawl' is an anagram of 'BARN-OWL'.
'such' is the link.
Can you help me to learn more?
(Other definitions for barn owl that I've seen before include "Countryside bird" , "Endangered night bird" , "Mottled buff and white night bird" , "Large hunting bird" , "Flier" .)