Other interesting terms associated with birds:

quail - to lose courage; become cowed or fearful.

grouse - to complain, typically with sustained grumbling.

hawk - (n) one who preys on his fellow men (as a swindler)
(v) to make an effort to raise phlegm from the throat; to clear the throat noisily.
(v) to advertise or peddle (goods) in the street by shouting.

snipe - to shoot from a hidden position at individuals of an enemy force.