δ13C and δ15N in Humboldt squid beaks: understanding potential geographic population connectivity and movement  

作　　者：Bilin Liu Xinjun Chen Weiguo Qian Yue Jin Jianhua Li 

机构地区：[1]College of Marine Sciences,Shanghai Ocean University,Shanghai 201306,China [2]National Engineering Research Center for Oceanic Fisheries,Shanghai 201306,China [3]Key Laboratory of Sustainable Exploitation of Oceanic Fisheries Resources,Ministry of Education,Shanghai 201306,China [4]Key Laboratory of Oceanic Fisheries Exploration,Ministry of Agriculture,Shanghai 201306,China [5]Scientific Observing and Experimental Station of Oceanic Fishery Resources,Ministry of Agriculture,Shanghai 201306,China [6]Laboratory for Marine Fisheries Science and Food Production Processes,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China

出　　处：《Acta Oceanologica Sinica》2019年第10期53-59,共7页海洋学报（英文版）

基　　金：The Shanghai Pujiang Program under contract No.18PJ1404100;the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning under contract No.0810000243;the National Natural Science Foundation of China under contract Nos 41306127 and 41276156

摘　　要：We quantified theδ^13C andδ^15N values in the lower beaks of Humboldt squid,Dosidicus gigas,collected from international waters off Costa Rica,Ecuador,Peru and Chile by Chinese squid jigging vessels during 2009,2010 and 2013.There was a significant difference in the isotopic values among regions with the lowest value off Ecuador and the highest off Chile,which were interpreted as a function of trophic effects as well as baseline values.However,constant trophic level of D.gigas across its geographic range showed that spatial variation in the baseline of primary production is the main driver responsible for the observed geographic isotope variability.Inter-regional difference and intra-regional convergence of isotope values indicated squid off Costa Rica,Ecuador and Chile belong to different geographically segregated populations,which were previously proved by integrated population identifying method.In contrast,the higher variations inδ^13C andδ^15N values in a given size group suggest the squid off Peru move and forage in different places.Moreover,potential population exchange could be responsible for the overlap of the isotope values between the squid off Peru and off Chile.On the whole,the spatial difference in isotopic values of Humboldt squid beaks improves our understanding of potential geographic population connectivity and movement.We quantified the δ13 C and δ15 N values in the lower beaks of Humboldt squid, Dosidicus gigas, collected from international waters off Costa Rica, Ecuador, Peru and Chile by Chinese squid jigging vessels during 2009, 2010 and 2013. There was a significant difference in the isotopic values among regions with the lowest value off Ecuador and the highest off Chile, which were interpreted as a function of trophic effects as well as baseline values. However, constant trophic level of D. gigas across its geographic range showed that spatial variation in the baseline of primary production is the main driver responsible for the observed geographic isotope variability.Inter-regional difference and intra-regional convergence of isotope values indicated squid off Costa Rica, Ecuador and Chile belong to different geographically segregated populations, which were previously proved by integrated population identifying method. In contrast, the higher variations in δ13 C and δ15 N values in a given size group suggest the squid off Peru move and forage in different places. Moreover, potential population exchange could be responsible for the overlap of the isotope values between the squid off Peru and off Chile. On the whole, the spatial difference in isotopic values of Humboldt squid beaks improves our understanding of potential geographic population connectivity and movement.

关 键 词：stable isotope Dosidicus GIGAS beaks GEOGRAPHIC variability TROPHIC level the eastern PACIFIC Ocean 

分 类 号：O57[理学—粒子物理与原子核物理]