Octopus fisheries have prospered in many areas of the world ocean over the last six decades. Despite degradation and overexploitation of Chinese coastal ecosystems, octopus has become a stable Chinese domestic fishery...Octopus fisheries have prospered in many areas of the world ocean over the last six decades. Despite degradation and overexploitation of Chinese coastal ecosystems, octopus has become a stable Chinese domestic fishery species. Among the octopus species in the Bohai and Yellow, East and South China Seas, Amphioctopus fangsiao(d'Orbigny [in Férussac & d'Orbigny], 1839–1841) plays an increasingly important role both economically and ecologically. However, no systematic research has been conducted on its biology and population dynamics in the China Seas. In this study, we characterized the growth and distribution of A. fangsiao in Haizhou Bay, Yellow Sea based on four years of trawl survey data. As the results, A. fangsiao is characterized by allometric growth and an overall sex ratio of 0.97 with a slight male bias. Small octopus can be observed through a whole year, suggesting that A. fangsiao may have an extended or continuous spawning season. A. fangsiao may migrate short distances along with seasonal changes and coastal currents, considering they overwinter in the offshore water and spawn in the inshore water. In addition to fishing pressure, annual variations in the population structure and biomass appeared to be influenced by ambient water temperature. These results provide basic biological information for a better understanding of the population dynamics and the ecological importance of A. fangsiao.展开更多
Amphioctopus fangsiao(Cephalopoda:Octopodidae)is an important commercial species in the coastal waters of China.In recent years,however,the resource of A.fangsiao have declined because of habitat destruction and overf...Amphioctopus fangsiao(Cephalopoda:Octopodidae)is an important commercial species in the coastal waters of China.In recent years,however,the resource of A.fangsiao have declined because of habitat destruction and overfishing.To analyze the genetic variations of A.fangsiao caused by the fluctuation of resources,the population genetic structure of nine sampling locations collected from the Bohai Sea to the South China Sea were investigated,using mtDNA COI fragments and microsatellite DNA.The results of F-statistics,AMOVA,STRUCTURE and PCA analyses showed three phylogeographic clades(Clades A,B and C),revealing limited genetic exchange between north and south populations.These clades diverged in 2.23(Clades A and B)and 3.67(Clades A,B and C)million years ago,during the dramatic environmental fluctuations,such as sea level and temperature changes,have exerted great influence on the survival distribution pattern of global organisms.Our results for low genetic connectivity among A.fangsiao populations provide insights into the development of management strategies,that is,to manage this species as separate management unit.展开更多
Marine organisms cannot grow and reproduce without proper metabolic regulation.Within a metabolic network,problems with a given link will affect the normal life activities of the organism.Many metabolic mechanisms ass...Marine organisms cannot grow and reproduce without proper metabolic regulation.Within a metabolic network,problems with a given link will affect the normal life activities of the organism.Many metabolic mechanisms associated with behaviors of Am-phioctopus fangsiao are still unclear.Moreover,as a factor affecting the normal growth of A.fangsiao,egg protection has rarely been considered in previous behavioral studies.In this research,we analyzed the transcriptome profile of gene expression in A.fangsiao egg-unprotected larvae and egg-protected larvae,and identified 818 differentially expressed genes(DEGs).We used GO and KEGG enrichment analyses to search for metabolism-related DEGs.Protein-protein interaction networks were constructed to examine the interactions between metabolism-related genes.Twenty hub genes with multiple protein-protein interaction relationships or that were involved in multiple KEGG signaling pathways were obtained and verified by quantitative RT-PCR.We first studied the effects of egg protection on the metabolism of A.fangsiao larvae by means of protein-protein interaction networks,and the results provide va-luable gene resources for understanding the metabolism of invertebrate larvae.The data serve as a foundation for further research on the egg-protecting behavior of invertebrates.展开更多
Amphioctopus fangsiao is an important fishery resource in northern coastal China,and there is an interest to develop its commercial cultivation under controlled conditions.In this study,we describe the embryonic devel...Amphioctopus fangsiao is an important fishery resource in northern coastal China,and there is an interest to develop its commercial cultivation under controlled conditions.In this study,we describe the embryonic development of A.fangsiao from eggs to hatchlings,focusing on the formation of the mantle,eyes and arms.Results indicate that this species has several favorable characteristics for aquaculture,such as a short incubation period and a large body size of hatchlings.During the organogenesis,the primordia of organs,including the optic sac and arm crown,first appeared at stage VIII;then the mantle primordium,eye primordia and arm crown become visible at stage IX-X,and the rudiment of embryo(mantle,eyes and arms)was completely outlined at stage XI.The retinal pigment appeared yellowish at stage X-XI and gradually deepens in pigmentation in the subsequent stages,turning from yellowish to yellow,red,dark-red and eventually black.At stage XV,the primary lid fold,with only a circular opening remaining,covered the eye,and the dorsal ocular edge did not reach the ventral side until hatching(day 1-7).Afterwards,about 24 days after hatching,both the dorsal and ventral sides of eyelid could contract freely,with an oval and elongate slit remaining that was a miniature version of the adult morphology.The chromatophores and ink sac appeared at stage XIV.These observations provide a foundation for the reproductive biology and aquaculture of A.fangsiao and also offer an important reference for the research of embryonic development in related species.展开更多
As fish stocks have been overexploited and catches have decreased over the last few years,the cephalopod catch has increased globally to the point that they are now among the most important marine resources in the wor...As fish stocks have been overexploited and catches have decreased over the last few years,the cephalopod catch has increased globally to the point that they are now among the most important marine resources in the world.Climate change and hu-man activities greatly affect the growth and abundance of cephalopods.Understanding how the individual growth of key species varies and how they respond to environmental changes is essential for an effective fishery management.Loliolus beka and Amphioc-topus fangsiao are two dominant species in the cephalopod community of Yellow Sea(YS).Both of them are commercially impor-tant and have great ecological values.Herein,we compared the body weights(BW)of these two species from 2011 to 2018 based on an analysis of biological parameters(i.e.,mantle length and BW)from trawl surveys in the YS.Considerable temporal variations in the BW of the two species are apparent.Specifically,the BW of L.beka was the lowest in 2011 and the highest in 2017,and the well growth was noted in 2015-2018.The BW of A.fangsiao was the lowest in 2013 and the highest in 2016,while well growth was ob-served in 2015-2016.Mixed-effect models indicate that the BW of these species correlates significantly with the sea surface tem-perature(SST)and Southern Oscillation Index(SOI),suggesting the impact of the regional environment associated with strong ENSO events on BW.In a different response window,growth increases with increased SST and decreases with increased SOI.The consistent patterns of the BW of these cephalopods in response to environmental factors demonstrate they can be employed as indi-cator species for studying environmental change in the YS.Our results improve the understanding of the responses of cephalopods to environmental changes in the YS,as well as the mechanisms that drive their growth.Such information is critical for the effective management and sustainable development of cephalopod fisheries in this region.展开更多
基金partially supported by the National Key R&D Program of China (Nos. 2018YFD0900902,2018YFD0900903)the National Natural Science Foundation of China (Nos. 41861134037,41930534)the ‘Fundamental Research Funds for the Central Universities’ to Ocean University of China (Nos. 201762015,20182201)。
文摘Octopus fisheries have prospered in many areas of the world ocean over the last six decades. Despite degradation and overexploitation of Chinese coastal ecosystems, octopus has become a stable Chinese domestic fishery species. Among the octopus species in the Bohai and Yellow, East and South China Seas, Amphioctopus fangsiao(d'Orbigny [in Férussac & d'Orbigny], 1839–1841) plays an increasingly important role both economically and ecologically. However, no systematic research has been conducted on its biology and population dynamics in the China Seas. In this study, we characterized the growth and distribution of A. fangsiao in Haizhou Bay, Yellow Sea based on four years of trawl survey data. As the results, A. fangsiao is characterized by allometric growth and an overall sex ratio of 0.97 with a slight male bias. Small octopus can be observed through a whole year, suggesting that A. fangsiao may have an extended or continuous spawning season. A. fangsiao may migrate short distances along with seasonal changes and coastal currents, considering they overwinter in the offshore water and spawn in the inshore water. In addition to fishing pressure, annual variations in the population structure and biomass appeared to be influenced by ambient water temperature. These results provide basic biological information for a better understanding of the population dynamics and the ecological importance of A. fangsiao.
基金The National Natural Science Foundation of China under contract Nos 32170536 and 31672257。
文摘Amphioctopus fangsiao(Cephalopoda:Octopodidae)is an important commercial species in the coastal waters of China.In recent years,however,the resource of A.fangsiao have declined because of habitat destruction and overfishing.To analyze the genetic variations of A.fangsiao caused by the fluctuation of resources,the population genetic structure of nine sampling locations collected from the Bohai Sea to the South China Sea were investigated,using mtDNA COI fragments and microsatellite DNA.The results of F-statistics,AMOVA,STRUCTURE and PCA analyses showed three phylogeographic clades(Clades A,B and C),revealing limited genetic exchange between north and south populations.These clades diverged in 2.23(Clades A and B)and 3.67(Clades A,B and C)million years ago,during the dramatic environmental fluctuations,such as sea level and temperature changes,have exerted great influence on the survival distribution pattern of global organisms.Our results for low genetic connectivity among A.fangsiao populations provide insights into the development of management strategies,that is,to manage this species as separate management unit.
基金supported by the earmarked fund for the Modern Agro-industry Technology Research System(No.CARS-49)the Natural Science Foundation of Shan-dong Province(No.ZR2019BC052)the National Natural Science Foundation of China(No.42006077).
文摘Marine organisms cannot grow and reproduce without proper metabolic regulation.Within a metabolic network,problems with a given link will affect the normal life activities of the organism.Many metabolic mechanisms associated with behaviors of Am-phioctopus fangsiao are still unclear.Moreover,as a factor affecting the normal growth of A.fangsiao,egg protection has rarely been considered in previous behavioral studies.In this research,we analyzed the transcriptome profile of gene expression in A.fangsiao egg-unprotected larvae and egg-protected larvae,and identified 818 differentially expressed genes(DEGs).We used GO and KEGG enrichment analyses to search for metabolism-related DEGs.Protein-protein interaction networks were constructed to examine the interactions between metabolism-related genes.Twenty hub genes with multiple protein-protein interaction relationships or that were involved in multiple KEGG signaling pathways were obtained and verified by quantitative RT-PCR.We first studied the effects of egg protection on the metabolism of A.fangsiao larvae by means of protein-protein interaction networks,and the results provide va-luable gene resources for understanding the metabolism of invertebrate larvae.The data serve as a foundation for further research on the egg-protecting behavior of invertebrates.
基金the following research grants:The Fundamental Research Funds for the Central Universities(201822022)Fisheries Technological Innovation and Promotion Project of Jiangsu Province(Y2017-7).
文摘Amphioctopus fangsiao is an important fishery resource in northern coastal China,and there is an interest to develop its commercial cultivation under controlled conditions.In this study,we describe the embryonic development of A.fangsiao from eggs to hatchlings,focusing on the formation of the mantle,eyes and arms.Results indicate that this species has several favorable characteristics for aquaculture,such as a short incubation period and a large body size of hatchlings.During the organogenesis,the primordia of organs,including the optic sac and arm crown,first appeared at stage VIII;then the mantle primordium,eye primordia and arm crown become visible at stage IX-X,and the rudiment of embryo(mantle,eyes and arms)was completely outlined at stage XI.The retinal pigment appeared yellowish at stage X-XI and gradually deepens in pigmentation in the subsequent stages,turning from yellowish to yellow,red,dark-red and eventually black.At stage XV,the primary lid fold,with only a circular opening remaining,covered the eye,and the dorsal ocular edge did not reach the ventral side until hatching(day 1-7).Afterwards,about 24 days after hatching,both the dorsal and ventral sides of eyelid could contract freely,with an oval and elongate slit remaining that was a miniature version of the adult morphology.The chromatophores and ink sac appeared at stage XIV.These observations provide a foundation for the reproductive biology and aquaculture of A.fangsiao and also offer an important reference for the research of embryonic development in related species.
基金supported by the National Natural Science Foundation of China(Nos.41930534 and 41861134037).
文摘As fish stocks have been overexploited and catches have decreased over the last few years,the cephalopod catch has increased globally to the point that they are now among the most important marine resources in the world.Climate change and hu-man activities greatly affect the growth and abundance of cephalopods.Understanding how the individual growth of key species varies and how they respond to environmental changes is essential for an effective fishery management.Loliolus beka and Amphioc-topus fangsiao are two dominant species in the cephalopod community of Yellow Sea(YS).Both of them are commercially impor-tant and have great ecological values.Herein,we compared the body weights(BW)of these two species from 2011 to 2018 based on an analysis of biological parameters(i.e.,mantle length and BW)from trawl surveys in the YS.Considerable temporal variations in the BW of the two species are apparent.Specifically,the BW of L.beka was the lowest in 2011 and the highest in 2017,and the well growth was noted in 2015-2018.The BW of A.fangsiao was the lowest in 2013 and the highest in 2016,while well growth was ob-served in 2015-2016.Mixed-effect models indicate that the BW of these species correlates significantly with the sea surface tem-perature(SST)and Southern Oscillation Index(SOI),suggesting the impact of the regional environment associated with strong ENSO events on BW.In a different response window,growth increases with increased SST and decreases with increased SOI.The consistent patterns of the BW of these cephalopods in response to environmental factors demonstrate they can be employed as indi-cator species for studying environmental change in the YS.Our results improve the understanding of the responses of cephalopods to environmental changes in the YS,as well as the mechanisms that drive their growth.Such information is critical for the effective management and sustainable development of cephalopod fisheries in this region.
