A PRELIMINARY-STUDY OF THE EFFECTS OF ECOLOGICALLY RELEVANT SOUNDS ON THE BEHAVIOR OF CAPTIVE LOWLAND GORILLAS

This exploratory study evaluated the effects of ecologically relevant sounds on captive lowland gorillas (Gorilla gorilla gorilla), housed in the night quarters adjacent to their new exhibit at the San Diego Zoo. The behaviour of four western lowland gorillas was sampled using remote videotaping under each of four noise conditions associated with captive housing (quiet, ventilation on, bonobo vocalization playbacks and caretaker sounds) and each of two sound conditions (rain forest sounds 'off', rain forest sounds 'on'). Significant differences in behaviour across noise conditions were found; these differences were ameliorated for infants, but only partially for adults by the rain forest sounds. The two adults responded to the rain forest sounds with increased agitation. The preliminary nature of these results is discussed.