Bird broadcast about salmon (7)
I believe the answer is:
sparrow
'bird' is the definition.
(sparrow is a kind of bird)
'broadcast about salmon' is the wordplay.
'broadcast' becomes 'sow' (sowing is a kind of broadcasting).
'about' means one lot of letters goes inside another.
'salmon' becomes 'parr' (I've seen this before).
'sow' going around 'parr' is 'SPARROW'.
(Other definitions for sparrow that I've seen before include "Small songbird" , "(Formerly very) common British bird" , "one on the wing" , "Common small bird" , "House bird" .)