Hawaii state bird (4)
I believe the answer is:
nene
'hawaii state bird' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for nene that I've seen before include "Northants river" , "River navigable to Northampton" , "Hawaiian goose; English river" , "River of Peterborough; goose" , "Northampton's river" .)