Crow first settled in a watercraft (5)
I believe the answer is:
boast
'crow' is the definition.
(I've seen this in another clue)
'first settled in a watercraft' is the wordplay.
'first settled' becomes 's' (1st letter of 'settled').
'in' is an insertion indicator.
'a watercraft' becomes 'boat' (I've seen this in another clue).
's' inserted within 'boat' is 'BOAST'.
(Other definitions for boast that I've seen before include "something to brag about" , "Brag about sabot" , "Talk proudly" , "shot off the side wall" , "Blow one's own trumpet" .)