Page 97 - 《水产学报》2025年第8期

杨凡，等 水产学报, 2025, 49(8): 089308

Feeding ecology of Sepiella maindroni based on
stomach contents analysis and stable isotope

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YANG Fan , LIU Mingzhi , JIANG Rijin , YIN Rui , LI Pengfei , LIANG Jun ,
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XU Kaida , ZHOU Yongdong , XU Hanxiang 1,2
1. Key Laboratory of Sustainable Utilization of Technology Research for Fishery Resources of Zhejiang Province,
Scientific Observing and Experimental Station of Fishery, Resources for Key Fishing Grounds,
Ministry of Agriculture and Rural Affairs, Zhejiang Marine Fisheries Research Institute, Zhoushan 316021, China;
2. Marine and Fisheries Research Institute, Zhejiang Ocean University, Zhoushan 316021, China
Abstract: Sepiella maindroni was once an important economic species along the coast of China, but its resources were exceed-
ingly depleted due to unreasonable exploitation, in addition, the natural habitat of S. maindroni is also being destroyed. To pre-
vent resource recession, relevant departments were restored by enhancing and releasing conservation measures. After several
years of efforts, preliminary signs of resource recovery were observed. In order to understand the feeding conditions of S. main-
droni after resource changes, 278 samples were collected from Zhongjieshan Islands in October 2021, and their feeding habits
were analyzed by stomach contents. The results of stomach contents showed that the S. maindroni mainly feed on seven groups,
including fish, shrimp, and so on, among which shrimp account for the largest proportion (IRI=45.04%), followed by fish
(IRI=26.74%) and crab (IRI=24.37%). Stable isotope was also used to analyze S. maindroni for revealing the long-term feed-
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ing patterns. The δ C values of the S. maindroni ranged from −18.21 ‰ to −15.85 ‰, with an average value of
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−17.01‰±0.68‰. The δ N values ranged from 8.19‰ to 12.28‰, with an average value of 10.18‰±1.01‰. Pearson
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analysis showed that the δ C value of muscle was not significantly correlated with the mantle length, but the δ N value was
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significantly positively correlated with the the mantle length (P<0.01). According to the δ N value, the average trophic level of
the S. maindroni in the Zhongjieshan Islands was 3.34±0.31. Stable isotope values showed that the contribution rate of food
source from high to low is Zooplankton, Cephalopod, Crustaceans, fish and Shellfish. As the mantle length changed, the S.
maindroni tended to feed on higher trophic level baits, such as fish and Cephalopods. S. maindroni has extensive feeding habit,
moreover, it also has to do with the species richness of the ocean where it lives. With the development of the individual, the
feeding organs and digestive organs gradually mature, and the activity and feeding ability are enhanced, and the predation abil-
ity is stronger. The bait organisms tend to be small fish and Cephalopods. In this study, the ecological characteristics of S. main-
droni in the waters of Zhongjieshan Islands were described, which can provide basic information for the resource recovery of
this species and the structural characteristics of the food web in this area.
Key words: Sepiella maindroni; stomach contents analysis; stable isotope; feeding ecology; trophic level
Corresponding author: JIANG Rijin. E-mail: jiangridge@163.com

Funding projects: Investigation and Evaluation of Important Economic Spawning Grounds in the Nearshore Waters of Zheji-
ang (HYS-CZ-202329); Dynamic Monitoring and Survey of Fisheries Resources in Zhejiang Province Fishing Grounds (HYS-
CZ-202314)

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