This study investigated context-dependent characteristics of vocalizations in captive bottlenose dolphins (Tursiops truncatus) under different behavioral situations in Korea. The experiment was conducted on July 21, 2025, at the Whale Ecology Experience Center in Ulsan, Korea, involving four captive bottlenose dolphins housed together in a single tank. Four experimental conditions were established: (1) a normal condition without external disturbance, (2) a feeding condition in which a trainer threw food into the tank, (3) a training condition involving responses to trainer signals, and (4) a toy-provided condition. Dolphin vocalizations were recorded for a total of 90 minutes using an Aquafeeler IV A and AQH-200D hydrophone (10 Hz-200 kHz, sensitivity -220 dB re 1 V/μPa) while behavioral data were simultaneously collected using tank monitoring cameras. Acoustic analyses were conducted using PAMGuard software. A total of 197 whistles and 378 buzzes and burst-pulses were recorded during the experiment. In the normal condition, dolphins swam freely and predominantly produced whistles within a frequency range of 6.81-23.82 kHz. During the feeding condition, the production of whistles, buzzes, and burst-pulses decreased while click trains associated with food searching behavior were mainly observed, typically lasting 0.9-1.8 seconds. In the training condition, dolphins primarily produced buzzes and burst-pulses, often accompanied by low-frequency tonal components (1.55 – 8.13 kHz) in response to trainer signals. In the toy-provided condition, dolphins produced clicks associated with object exploration along with buzzes and burst-pulses ranging from 1.3 to 10.8 kHz. Whistles were most frequently recorded in the normal condition accounting for 72.5% of total whistle occurrences whereas buzzes and burst-pulses were most frequent in the toy-provided condition (51.1%). These results demonstrate that bottlenose dolphin vocalizations vary systematically according to behavioral context, suggesting that vocalization frequency and patterns should be useful indicators for inferring behavioral states and have potential applications in passive acoustic monitoring and biological monitoring technologies.

서 론
재료 및 방법
    발성음의 녹음 장치 및 분석 방법
    수조 내 사육 중인 큰돌고래의 특정 상황 설정
결과 및 고찰
    큰돌고래 사육 중 일반적으로 발생하는 상황별 발성음 특성
    먹이 급이 상황
    장난감 놀이 상황
    사육사와의 훈련 상황
    호기심, 경계 상황
    큰돌고래 휘슬음 유형
결 론
References

• 황두진(전남대학교 해양생산관리학과 교수) | Doo-Jin HWANG (Professor, Department of Marine Production Management, Chonnam National University, Yeosu 59626, Korea) Corresponding author
• 신중로(전남대학교 수산과학과 대학원생) | Joong-Ro SHIN (Graduate Student, Department of Fisheries Science, Chonnam National University, Yeosu 59626, Republic of Korea)
• 강태종(전남대학교 수산과학과 대학원생) | Tae-Jong KANG (Graduate Student, Department of Fisheries Science, Chonnam National University, Yeosu 59626, Republic of Korea)
• 민은비(전남대학교 수산과학과 대학원생) | Eun-Bi MIN (Graduate Student, Department of Fisheries Science, Chonnam National University, Yeosu 59626, Republic of Korea)
• 오로라(전남대학교 수산과학과 대학원생) | Ro-Ra AU (Graduate Student, Department of Fisheries Science, Chonnam National University, Yeosu 59626, Republic of Korea)
• 김슬기(장생포 고래생태체험관 사육사) | Seul-Ki KIM (Zookeeper, Jangseongpo Whale Ecology Experience Center, Ulsan 44780, Republic of Korea)
• 김동희(장생포 고래생태체험관 사육사) | Dong-Hee KIM (Zookeeper, Jangseongpo Whale Ecology Experience Center, Ulsan 44780, Republic of Korea)
• 전현진(장생포 고래생태체험관 사육사) | Hyun-Jin JEON (Zookeeper, Jangseongpo Whale Ecology Experience Center, Ulsan 44780, Republic of Korea)