Localization of brief sounds by pigeons

The ability of pigeons (Columbia livia) to localize brief sounds was assessed using a two‐choice procedure. The pigeons first pecked a lighted key located at the center of a 76 cm. semicircle triggering a sound from one of two speakers separated by 120° at the periphery. If they then walked to the sound source and pecked a lighted key above it, they were rewarded with momentary access to grain. Although at first they were reluctant to approach the active speaker, eventually they demonstrated their ability to localize either a brief white noise burst or a tone pip. However, their ability to localize a tone pip varied markedly with frequency. A symptotic performance levels were found to be above 90% at 125 Hz and 250 Hz, 73% at 500 Hz, 59% at 1 kHz, 60% at 2 kHz, 67% at 4 kHz, and above 90% again at 8 kHz. Therefore, pigeons can lozalize low and high frequencies well, but middle frequencies (1K and 2K) only with difficulty. Localization in this midrange of frequencies is greatly and immediately enhanced when a narrow band of white noise is substituted for the tone pip.