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

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