Vocal tract filtering and the "coo" of doves

J Acoust Soc Am. 2004 Dec;116(6):3750-6. doi: 10.1121/1.1811491.


Ring doves (Streptopelia risoria) produce a "coo" vocalization that is essentially a pure-tone sound at a frequency of about 600 Hz and with a duration of about 1.5 s. While making this vocalization, the dove inflates the upper part of its esophagus to form a thin-walled sac structure that radiates sound to the surroundings. It is a reasonable assumption that the combined influence of the trachea, glottis and inflated upper esophagus acts as an effective band-pass filter to eliminate higher harmonics generated by the vibrating syringeal valve. Calculations reported here indicate that this is indeed the case. The tracheal tube, terminated by a glottal constriction, is the initial resonant structure, and subsequent resonant filtering takes place through the action of the inflated esophageal sac. The inflated esophagus proves to be a more efficient sound radiating mechanism than an open beak. The action of this sac is only moderately affected by the degree of inflation, although an uninflated esophagus is inactive as a sound radiator. These conclusions are supported by measurements and observations that have been reported in a companion paper.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Airway Resistance / physiology
  • Animals
  • Columbidae / physiology*
  • Esophagus / physiology*
  • Glottis / physiology*
  • Sound Spectrography*
  • Trachea / physiology*
  • Vocalization, Animal / physiology*