Fish from river seized by hawk (5)
I believe the answer is:
trout
'fish' is the definition.
(trout is a kind of fish)
'river seized by hawk' is the wordplay.
'river' becomes 'r'.
'seized by' is an insertion indicator.
'hawk' becomes 'tout' (I've seen this before).
'r' put inside 'tout' is 'TROUT'.
'from' is the link.
(Other definitions for trout that I've seen before include "Schubert work; fish" , "interfering old woman" , "Small salmonlike fish" , "Game fish related to salmon" , "Performance by five players" .)