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Article

Relationship between Tropical Tuna Catches, Acoustic-based Prey Distribution, and Oceanographic Environments in the Western Indian Ocean

서부 인도양 열대 다랑어 어획량과 음향자료 기반 먹이생물 분포 및 해양환경 간의 관계

JIHOON JUNG1
,
FREDRICH SIMANUNGKALIT1
,
DONGHA KANG12
,
NAIZHENG YAN3
,
JOOHYANG KIM4
,
SOMANG SONG4
,
YESEUL KIM5
,
SUNGHYUN NAM6
,
DONG-JIN KANG7
,
MYOUNGHEE KANG8*
정 지훈1
,
Simanungkalit Fredrich1
,
강 동하12
,
Yan Naizheng3
,
김 주향4
,
송 소망4
,
김 예슬5
,
남 성현6
,
강 동진7
,
강 명희8*
1Student, Department of Maritime Police and Production System, Graduate School, Gyeongsang National University, Tongyeong 53064, Korea
2Researcher, Fisheries Engineering Division, National Institute of Fisheries Science, Busan 46083, Korea
3Professor, School of Fisheries Sciences, Hokkaido University, Hakodate 041-8611, Japan
4Student, School of Earth and Environmental Sciences, Seoul National University, Seoul 08826, Korea
5Senior Researcher Specialist, Advanced Infrastructure Operations Center, Korea Institute of Ocean Science and Technology, Busan 49111, Korea
6Professor, School of Earth and Environmental Sciences/Research Institute of Oceanography, Seoul National University, Seoul 08826, Korea
7Vice President, Office of the Vice President, Korea Institute of Ocean Science and Technology, Busan 49111, Korea / Professor, Department of Ocean Science, University of Science and Technology, Daejeon 34113, Korea
8Professor, Department of Maritime Police and Production System/Institute of Marine Industry, Gyeongsang National University, Tongyeong 53064, Korea
1경상국립대학교 대학원 해양경찰시스템학과 대학원생
2국립수산과학원 수산공학과 연구원
3북해도대학교 수산과학부 교수
4서울대학교 대학원 지구환경과학부 대학원생
5한국해양과학기술원 첨단인프라운영센터 선임기술원
6서울대학교 지구환경과학부/해양연구소 교수
7한국해양과학기술원 부원장 / 과학기술연합대학원대학교 해양과학전공 교수
8경상국립대학교 해양경찰시스템학과/해양산업연구소 교수
*Corresponding Author
31 August 2026. pp. 74-89
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Abstract

Using acoustic data collected in the western Indian Ocean, tropical tuna catch data from the Indian Ocean Tuna Commission, and Copernicus-based oceanographic data, this study investigated the relationships among the catch distributions of bigeye tuna, skipjack tuna, and yellowfin tuna, the distribution of prey organisms, and oceanographic conditions. The Nautical Area Scattering Coefficient (NASC) was calculated using 38 kHz acoustic data obtained from the R/V Isabu of the Korea Institute of Ocean Science and Technology in December 2021, and was compared with tropical tuna catches and temperature, salinity, and dissolved oxygen data. The results showed that NASC was relatively high in the 9°-12°S and 3°-6°S areas, whereas tropical tuna catches tended to be concentrated in the northwestern and equatorial regions. Although all three tropical tuna species showed high catches in the northern and equatorial regions, their spatial distributions differed among species. Skipjack tuna and yellowfin tuna were mainly concentrated north of 3°S, whereas bigeye tuna was also partially caught south of 9°S. The Spearman correlation coefficient between NASC and tropical tuna catches was very low and not statistically significant (ρ = 0.029, p = 0.172). This was considered to be attributable to the spatiotemporal mismatch between the acoustic and catch data, as well as the limitations of the sample-based catch data. The oceanographic analysis showed that the northern and equatorial regions, where tuna catches were concentrated, partially overlapped with areas characterized by relatively high temperature and dissolved oxygen concentrations at a depth of 34 m. These conditions showed some similarity to the preferred environmental ranges of tropical tunas reported in previous studies. In addition, some significant correlations were observed between NASC and oceanographic variables; however, the absolute values of the correlation coefficients were generally low, indicating weak relationships. This study provides a preliminary integrated comparison of acoustic data, tropical tuna catch data, and oceanographic data in the western Indian Ocean, and its findings are expected to serve as baseline information for future investigations of ecological linkages among tuna resources, prey organisms, and oceanographic conditions.

Keywords
Tropical tunas
Indian Ocean
Echosounder
Prey organisms
Oceanographic conditions

서부 인도양에서 수집된 음향자료와 인도양 다랑어 위원회 열대 다랑어 어획자료 및 Copernicus 기반 해양환경 자료를 활용하여 눈다랑어, 가다랑어, 황다랑어의 어획 분포와 먹이생물 분포 및 해양환경 간의 관계를 조사하였다. 2021년 12월 한국해양과학기술원 연구선 이사부호에서 획득한 38 kHz 음향자료를 이용하여 해리면적산란계수(NASC)를 산출하였으며, 이를 열대 다랑어 어획량 및 수온, 염분, 용존산소 자료와 비교하였다. 분석 결과, NASC는 남위 9°-12° 및 남위 3°-6° 해역에서 상대적으로 높게 나타난 반면, 열대 다랑어 어획량은 북서부 및 적도 인근 해역에 집중되는 경향을 보였다. 열대 다랑어 3종 모두 북부 및 적도 인근 해역에서 높은 어획량을 나타냈으나, 종별 공간 분포에는 차이가 있었다. 가다랑어와 황다랑어는 주로 남위 3° 이북 해역에 집중되었고, 눈다랑어는 남위 9° 이남에서도 일부 어획이 나타났다. NASC와 열대 다랑어 어획량 간 스피어만 상관계수는 매우 낮았으며 통계적으로 유의하지 않았다(ρ = 0.029, p = 0.172). 이는 음향자료와 어획자료 간의 시·공간적 불일치와 표본 기반 어획자료의 한계에 기인한 것으로 판단된다. 해양환경 분석에서는 다랑어 어획이 집중된 북부 및 적도 인근 해역이 34 m 수심에서 비교적 높은 수온과 용존산소 농도가 나타난 구간과 일부 중첩되었으며, 이는 기존 연구에서 제시된 열대 다랑어의 선호 환경 범위와 일부 유사한 경향을 보였다. 또한 NASC와 해양환경 변수 간에는 일부 유의한 상관관계가 나타났으나, 전반적으로 상관계수의 절대값이 낮아 약한 수준의 관계를 보였다. 본 연구는 서부 인도양에서 음향자료와 열대 다랑어 어획자료 및 해양환경 자료를 통합적으로 비교·분석한 기초 연구로서, 향후 다랑어 자원과 먹이생물 및 해양환경 간의 생태적 연계성을 규명하기 위한 기반 자료로 활용될 수 있을 것으로 기대된다.

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Information
  • Publisher :The Korean Society of Oceanography
  • Publisher(Ko) :한국해양학회
  • Journal Title :The Sea Journal of the Korean Society of Oceanography
  • Journal Title(Ko) :한국해양학회지 바다
  • Volume : 31
  • No :2
  • Pages :74-89
  • Received Date : 2026-03-17
  • Revised Date : 2026-05-26
  • Accepted Date : 2026-06-07
  • DOI :https://doi.org/10.7850/jkso.2026.31.2.074
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