The effect of auditory enrichment, rearing method and social environment on the behavior of zoo-housed psittacines (Aves: Psittaciformes); implications for welfare

Abstract

The psychological and physiological effects of different genres of music are well documented in humans. These concepts have also been studied in kenneled dogs and some exotic animals, implying that animals may experience benefits similar to those of humans. This study tested the hypothesis that auditory enrichment changed the behavior of ten zoo-housed psittacines. All animals were exposed to six conditions of auditory stimulation; a ‘control’ (no auditory stimulation), and ‘experimental’ conditions, during which animals were presented with commercially-available CDs of classical music, pop music, natural rainforest sounds, parrot sounds and a talking radio. Each type of stimulation lasted two days, with a wash-out day between different stimulation conditions. We recorded key parameters relating to the birds’ social environment – whether they were group or single-housed and whether they had been hand or parent-reared. The parrots’ behaviour was recorded every minute for a 25 min period seven times a day using instantaneous sampling. The incidence of calm vocalisations and the level of preening changed with the different conditions. Birds exposed to rainforest and talking radio preened more than control birds. Birds exposed to several genres of auditory stimulation expressed fewer calm vocalisations than control birds. A further finding from this study was that hand-reared birds exhibited dramatically increased incidences of stereotypic behavior, more learned vocalisation and interacted less with enrichment than parent-reared and the implications of hand rearing for welfare are discussed. Similarly solo housed birds showed changes in behavior compared to group housed, such as less preening and more stereotypic behaviour. Hand reared, solo housed parrots express less normal behavior and maybe at risk of impaired welfare.