Scotsman was upset by the parrots (6)
I believe the answer is:
macaws
'the parrots' is the definition.
(macaw is a kind of parrot)
'scotsman was upset' is the wordplay.
'scotsman' becomes 'mac'.
'upset' indicates an anagram.
'was' is an anagram of 'aws'.
'mac'+'aws'='MACAWS'
'by' acts as a link.
(Other definitions for macaws that I've seen before include "More than one bird" , "Long-tailed parrots of Central and South America" , "Birds" , "Brightly-coloured parrots" , "Long-tailed, brilliantly-coloured parrots" .)