Page 93 - 《水产学报》2026年第2期

2 期 水 产 学 报 50 卷

light purse seine fishing production in the Indian Ocean from 2016 to 2021, combined with the statistical analysis of the interan-
nual variation and seasonal fluctuation of the yield and nominal CPUE, this study focused on the impact of time and space
factors on the nominal CPUE of S. oualaniensis using catch gravity center analysis, standard deviational ellipse modeling, and
cluster analysis, to explore and find out the variation law of the gravity center of the fishing ground and variation characterist-
ics of the central fishing ground in the interannual and seasonal. The results shown that the output was consistent with the
increasing trend of the number of fishing vessels, but the excessive number of fishing vessels wound lead to the decline of the
nominal CPUE; From 2016 to 2021, the center of fising ground gravity moved to the Northeast along a curve, and the nominal
CPUE high value areas in each year were concentrated at 12°-20° N, 58°-68° E; the period of the highest nominal CPUE and
output was from October to December, the period of the most widespread distribution of the S. oualaniensis was from October
to the following January, and the period of movement from high latitude to low latitude was from February to May; the distri-
bution latitude of the yield gravity center was higher (17°-18° N) from September to December, and lower (15.5°-16.5° N) from
January to May; the interannual fishing ground changed direction and the fishing ground changed direction in the production
month (September to April of the next year) were northeast southwest, consistent with the Somali ocean current direction.
Research had shown that when there were too many fishing vessels, the nominal CPUE would decrease, and the number of fish-
ing vessels should be reasonably controlled. In addition, attention should be paid to the annual and monthly variation patterns of
the S.oualaniensis fishing ground, and it should be reasonably applied to fishing activities. This study has better revealed the
temporal and spatial changes of the fishery resources and the distribution of the central fishing grounds of the S. oualaniensis in
the northwest Indian Ocean, providing a basis for its sustainable utilization of fisheries.
Key words: Symlectoteuthis oualaniensis; temporal and spatial distribution; standard deviational ellipse; yield center of gravity
analysis; cluster analysis; northwest Indian Ocean
Corresponding author: TANG Fenghua. E-mail: f-h-tang@163.com
Funding projects: National Key R & D Projects (2019YFD0901405); Shanghai Natural Science Foundation Project
(17ZR1439700); Open Subject Project of Key Laboratory of Sustainable Utilization Technology of Marine Fishery Resources
in Zhejiang Province (2020KF001)

https://www.china-fishery.cn 中国水产学会主办 sponsored by China Society of Fisheries
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