plSSN : 0374-8111 | elSSN : 2287-8815
plSSN : 0374-8111 | elSSN : 2287-8815
plSSN : 0374-8111elSSN : 2287-8815
김형태·박근창1·이사라·김지연·오우석1·박미선2·이경훈3*
국립부경대학교 수산물리학과, 1국립부경대학교 저탄소해양생산기술연구소, 2한국미래양식기술연구조합, 3국립부경대학교 해양생산시스템관리학부
This study investigated the bio-monitoring of finless porpoises Neophocaena asiaeorientalis in Hadong, Gyeongsangnam- do, South Korea and the impact of underwater noise on their vocalization and behavior. The research conducted visual surveys and Passive Acoustic Monitoring (PAM) to analyze the species' activity in coastal waters. The results showed that noise from fish farm machinery and vessels, while not directly harmful measured SPLPeak at 125-141 dB re μPa, affects their communication and feeding behavior. Normally, porpoises reduce their inter-click intervals (ICI) when approaching prey, but in noisy environments, the ICI increased to an average of 212-228 ms, making prey location more difficult. In both surveys, the ICI distribution showed a peak in the 5-55 ms range, followed by a decrease and a slight increase in the 300-400 ms range. The study also observed that porpoises are more active during sunrise and sunset, with click activity peaking between 05:00-10:00 and 13:00-19:00, and being highly responsive to ambient noise levels. While the noise did not exceed NOAA's threshold for auditory damage (202 dB re μPa SPLPeak), it still interfered with the porpoises' echolocation precision.
Bio-monitoring, Hydrophone, Neophocaena asiaeorientalis, PAM (Passive acoustic monitoring), Vocalization