The Collaborative International Dictionary of English v.0.48:

Cooey \Coo"ey\, Cooee \Coo"ee\, n. [Of imitative origin.]
   A peculiar cry uttered by the Australian aborigines as a call
   to attract attention, and also in common use among the
   Australian colonists. In the actual call the first syllable
   is much prolonged (k[=oo]"-) and the second ends in a shrill,
   staccato [=e]. To represent the sound itself the spelling
   cooee is generally used. [Written also cooie.]

   Within cooey, within earshot.
      [Webster 1913 Suppl.] Cooey