- 著者
-
田中 俊明
室山 泰之
- 出版者
- 日本霊長類学会
- 雑誌
- 霊長類研究 (ISSN:09124047)
- 巻号頁・発行日
- vol.31, no.1, pp.31-37, 2015-06-20 (Released:2015-08-07)
- 参考文献数
- 19
- 被引用文献数
-
1
The two experimental studies were conducted on a captive group of Japanese macaques at an enclosure in Primate Research Institute, Kyoto University, Japan. In Experiment I, ultrasonic sounds were used stimuli as playback experiment. We used the Yard Gard (Weiteck Inc.) as ultrasonic device, which can emit the sounds of three different frequencies (15kHz, 20kHz, and 26kHz) at the sound pressure level of 114 level of dB at 1m distance (Weitech 1995). Monkeys were exposed to three treatments consisting of 26kHz, 15kHz, and no sound (control) as one session in a day. The order of each treatment in a session was determined randomly, and the interval of each treatment was one hour. Total number of monkeys entering the experimental area and feeding durations did not differ among treatments, whereas feeding delay to the 25kHz sound was longer than that of other treatments. Feeding delay to the sounds of 25kHz and 16kHz was longer on the 1 st and 2nd experiment days than the other days. In Experiment II, turkeys vocalizations, which are emitted when they observe unfamiliar objects or hear big and/or unfamiliar sounds and one synthetic sound were used as playback. Monkeys were exposed to three treatments consisting of turkey vocalization playback, synthetic sound playback, and no sound (control) as one session. Monkeys fled immediately after the playback of turkey vocalization and took more than 50 sec to be back, but thus feeding duration to turkey vocalizations was longer than that of other treatments on the only 1st experiment day. Total number of monkeys entering the experiment area did not differ among treatments. Overall, the results of these experiments showed that unfamiliar acoustic stimuli may cause strong negative responses such as fleeing, but these responses will disappear in a short-term (ex. in a few days).