International Journal of Comparative Psychology

Domestic

chicks {Callus gallus domesticiis) were reared in pairs from day three post-hatching. On the fifth day of life, a chick was  separated from its brood mate and 30 sees, later the chicks' vocalizations were recorded for five minutes. The recordings were analysed using Canary 1.1 sound analysis system running on Mac II vx. Seven acoustic parameters of the peep vocalizations of female chicks were measured (duration (msec), maximum frequency (kHz), minimum frequency (kHz), difference between maximum and minimum frequency (kHz), peak frequency (kHz), energy (watts) and average power (joules)). During separation chicks produced peep calls that differed in structure. In total, 12 female chicks' vocalizations were examined and seven chicks produced three distinct peeps . These were classified as short, medium and long. Three calls of each type for each chick were examined. Short peeps have a narrow frequency range and short duration, medium peeps have a wider frequency range, longer duration and a short upper inversion preceding the descending frequency. Long peeps have the widest frequency range, the longest duration and have the most complex structure. The main finding of this study is that the chick of the domestic fowl can produce hree distinct types of peep call.