Analysis of feeding ecology of jumbo squid Dosidicus gigas in the high seas of southeast Pacific Ocean based on stable isotope technology
CAO Liangliang,LIU Bilin,LI Jianhua
1.College of Marine Sciences,Shanghai Ocean University,Shanghai 201306,China;2.Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources,Ministry of Education,Shanghai 201306,China;3.National Engineering Research Center for Oceanic Fisheries,Shanghai 201306,China;4.Key Laboratory of Oceanic Fisheries Exploration,Ministry of Agriculture and Rural Affairs,Shanghai 201306,China;5.Scientific Observing and Experimental Station of Oceanic Fishery Resources,Ministry of Agriculture and Rural Affairs,Shanghai 201306,China
Abstract: Feeding habits and trophic niche were investigated in samples of jumbo squid Dosidicusgigas collected by Chinese squid fishing vessels during production in the high seas of Peru and Ecuador in the southeast Pacific Ocean from June to December 2019 by a stable isotope method.Results showed that there was significantly higher δ13C and δ15N in muscle of jumbo squid in the high seas of Ecuador than those in the high seas of Peru (P<0.05),with the range of δ13 C from -19.81‰ to -17.38‰ in muscle of the jumbo squid,the range of δ15N from 9.36‰ to 14.43‰ in the high seas of Ecuador;and the δ13C range of jumbo squid from -20.77‰ to -17.99‰,and the value of δ15N range from 7.65‰ to 13.60‰ in the high seas of Peru.The analysis of generalized additive models(GAM)revealed that δ13C and δ15N in muscles of jumbo squid in the high seas of Ecuador were not significantly correlated with mantle length (P>0.05),while the muscles δ13C and δ15N of jumbo squid were significantly related to mantle length in the high seas of Peru (P<0.05).In the high seas of Ecuador,there was no significant difference in the δ13C of female and male individuals with mantle length growth (P>0.05),without significant differences in δ15N of male individuals with mantle length growth (P>0.05),and with significant differences in the δ15N in female individuals with mantle length growth (P<0.05).In the high seas of Peru,there was no significant difference in δ13C and δ15N between male and female individuals with mantle length growth (P>0.05).In the high seas of Ecuador,there was no significant difference in δ13C in maturity stage Ⅰ to Ⅲ (P<0.05),with significant difference in δ15N in maturity stage Ⅰ to Ⅲ (P<0.05).The maximal δ13C was observed in jumbo squid at the maturity stage Ⅲ (P<0.05),and the maximal δ15N in jumbo squid was found at the maturity stage Ⅱ (P<0.05)in the high seas of Peru.Trophic niche analysis indicated that jumbo squida was in low trophic niche (SEAc=1.462‰)in the high seas of Ecuador,being affected by the isotope baseline and feeding，without difference in the muscle δ13C and δ15N in different mantle length.In the high seas of Ecuador,however,jumbo squid had high trophic niche (SEAc=2.182‰)and was affected by the feeding effect,with great difference in muscle δ13C and δ15N in different mantle length.Meanwhile,there was higher trophic niche in female jumbo squid than that in male individuals in both seas.The findings indicated that jumbo squida was in low trophic niche and had narrow food sources in the high seas of Peru under El Nio climate conditions.
操亮亮, 刘必林, 李建华. 基于稳定同位素技术的东南太平洋公海茎柔鱼摄食生态分析[J]. 大连海洋大学学报, 2022, 37(1): 120-128.
CAO Liangliang, LIU Bilin, LI Jianhua. Analysis of feeding ecology of jumbo squid Dosidicus gigas in the high seas of southeast Pacific Ocean based on stable isotope technology. Journal of Dalian Ocean University, 2022, 37(1): 120-128.
2022, Vol. 37 
