Abstract
Echolocation calls of the Oriental free-tailed bat, Tadarida insignis, were recorded at five sites in the southwestern region of Shikoku, Japan. The pulse duration (D) of the calls averaged 17.5ms, the frequency of maximum energy of the pulse (PF) averaged 13.5kHz, and end frequency (EF) averaged 11.3kHz, start frequency (SF) averaged 18.7 kHz, bandwidth (BW) averaged 7.4kHz, interpulse interval (IPI) averaged 495.3ms. The duration and frequency of pulses obtained for this species in the southwestern Shikoku region did not differ significantly from those reported in the Kyushu and Chugoku, Chubu regions. While some variation in search phase call structure between sites was suggested, the overall results were considered to be continuous.
