Directionality of Avian Vocalizations: A Laboratory Study

Abstract
Pure tones of 1, 2, 4, 8, and 10 kHz were broadcast from the body of a dead starling Sturnus vulgaris, and sound pressure levels were measured through 360.degree. in three planes. At high frequencies (8 and 10 kHz) there were large troughs in sound pressure levels in the acoustic "shadow" of the bird''s body. A physical model based on sound interference phenomena predicts similar patterns of sound pressure levels.