Article
Environmental Sciences
Yi-Chen Cheng, Sen Jan, Chung-Chi Chen
Summary: Swordtip squid is a commercially important species in the southern East China Sea. Its annual catch per unit effort (CPUE) is influenced by temperature anomalies and the intrusion of warm water from the Kuroshio current. A warmer environment favors recruitment and catch of swordtip squid, while the intrusion of warm water benefits the growth of larvae, maintaining a certain level of CPUE. The blocking of the Kuroshio intrusion due to cold and less salty China Coastal Water in certain years resulted in anomalously low CPUE. Evaluating the dominance of warm Kuroshio water and cold shelf water can help predict annual catches of swordtip squid.
FRONTIERS IN MARINE SCIENCE
(2022)
Article
Marine & Freshwater Biology
Nan Li, Peiwu Han, Chao Wang, Xinjun Chen, Zhou Fang
Summary: This study used LA-ICP-MS to analyze the trace element ratios in the statoliths of U. edulis in the East China Sea. The results showed significant differences in trace element ratios among different growth stages. The relationship between trace element ratios and water temperature was established, and the potential habitats were predicted and calculated based on this relationship.
Article
Engineering, Multidisciplinary
Ke-Yang Chang, Yu-Jie Hsu, Tzu-Yun Ching, Cheng-Hsin Liao, Chih-Shin Chen
Summary: The swordtip squid is a commercially important species in the coastal waters of the Indo-western Pacific region. However, there is limited information on its stock assessments, especially in the East China Sea. This study provides a standardized method for assessing the abundance of swordtip squid and highlights the importance of further stock assessment and fisheries management in the region.
JOURNAL OF MARINE SCIENCE AND TECHNOLOGY-TAIWAN
(2022)
Article
Agriculture, Dairy & Animal Science
Xiaodi Gao, Yazhou Jiang, Xingwei Yuan, Linlin Yang, Jianzhong Ling, Shengfa Li
Summary: The distribution of the swordtip squid in coastal China varies seasonally and is affected by different environmental variables, with its suitable habitat changing accordingly.
Article
Ecology
Nan Li, Zhou Fang, Xinjun Chen, Zhiping Feng
Summary: Uroteuthis edulis (U. edulis) is a commercially important cephalopod species widely distributed in the coastal waters of China. In this study, the statolith trace elements of spring and summer cohorts of U. edulis in the East China Sea were measured by Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). The analysis showed that calcium (Ca), sodium (Na), strontium (Sr), iron (Fe) and magnesium (Mg) were the top five elements in the spring and summer cohorts, with significant differences between two cohorts. Water temperature, salinity and mixed layer depth (MLD) were the key environmental variables affecting element concentration changes. The ratios of Sr/Ca, Ba/Ca, Na/Ca and Li/Ca can be used as the potential indicators to construct the habitat history of U. edulis.
REGIONAL STUDIES IN MARINE SCIENCE
(2021)
Article
Fisheries
Takuya Matsumoto, Maho Akita, Mariko Ogawa, Takanobu Goto
Summary: The study investigated the activities of taurine biosynthesis enzymes in the livers of spear squid and swordtip squid, revealing variations in enzyme activities between species. Spear squid showed higher CSD and CAD activities compared to swordtip squid, with the presence of CAO activity in the latter. Additionally, competitive inhibition experiments demonstrated that a single enzyme in spear squid catalyzes the decarboxylation of cysteinesulfinic and cysteic acids.
Article
Agriculture, Dairy & Animal Science
Rongpei Guo, Nan Li, Zhou Fang
Summary: The fecundity characteristics and spawning strategy of Uroteuthis edulis in the East China Sea were investigated. Observations were made on potential fecundity (PF), relative fecundity by dorsal mantle length (PFML) and relative fecundity by body weight (PFBW). The relationship between fecundity and a single biological indicator was measured, and generalized additive models (GAMs) were fit by adding environmental variables. The study provides valuable insights into the population dynamics of U. edulis, an economically and ecologically important species, for future management.
Article
Engineering, Multidisciplinary
Jing-Yu Chen, Tzu-Yun Ching, Chih-Shin Chen
Summary: This study examines the growth and maturation of the swordtip squid in the waters of the south-eastern coast of China and reveals a connection with the squid population in the southern East China Sea shelf.
JOURNAL OF MARINE SCIENCE AND TECHNOLOGY-TAIWAN
(2022)
Article
Oceanography
Nan Li, Yan Wang, Zhou Fang, Xinjun Chen, Zhiping Feng
Summary: This study explored the spawning season, growth patterns, and relationship with the environment of Swordtip squid (Uroteuthis edulis) in the East China Sea. The study found that the spawning season of U. edulis is nearly one year, with two peak periods in spring and summer. The growth of different groups was significantly affected by seasonal changes in water temperature, current velocity, and prey abundance.
ACTA OCEANOLOGICA SINICA
(2022)
Article
Fisheries
Tadanori Yamaguchi, Katsumi Takayama, Naoki Hirose
Summary: The study found that there are differences in size among mature female Swordtip squid born under different temperature conditions. Small mature female squid would hatch in the southern East China Sea in winter and migrate to the Sea of Amakusa via the Kuroshio Current. The analysis also revealed that the empirical water temperature history and the depth of the waters where the squid were caught were the two major differences between them. After reaching the minimum age of maturity, the squid could begin to mature when the water temperature in the bottom layer exceeded approximately 16 degrees Celsius and take about one month to reach full maturity.
FISHERIES RESEARCH
(2022)
Article
Fisheries
Nan Li, Peiwu Han, Xinjun Chen, Zhou Fang
Summary: This study determined the statolith microchemistry of U. edulis in different stocks using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and analyzed the differences in the ratio of various elements to Ca at different life history stages using a multiple regression tree model (MRT). The results showed that sodium (Na), magnesium (Mg), iron (Fe), strontium (Sr), and barium (Ba) were the effective elements in four stocks. The Sr/Ca and Ba/Ca ratios can be selected as key indicators to speculate on the migration route of U. edulis.
Article
Environmental Sciences
Zhaozhao Li, Yandong Liu, Dahai Zhang, Lijuan Feng, Xingliang He, Xiaoyong Duan, Xianguo Li, Huixiang Xie
Summary: This study provides a high-spatial-resolution analysis on the distributions, characteristics, and environmental risks of microplastics in the southern East China Sea. The results show that microplastics are commonly found in surface sediments, with higher concentrations near urban centers. The dominant types of microplastics are polyethylene and polyethylene terephthalate, mainly in the form of fibers and fragments, and have a size of 0.1-0.5 mm. The study highlights the complex interactions among physical, biological, and topographic factors that control the distribution and environmental risks of microplastics in coastal sediments.
MARINE POLLUTION BULLETIN
(2022)
Article
Ecology
Kurichithara K. Sajikumar, Geetha Sasikumar, J. Jayasankar, Vivekanand Bharti, V. Venkatesan, K. M. Jestin Joy, P. S. Alloycious, Kolliyil S. Mohamed
Summary: This study analyzed the age, growth, maturation, and spawning dynamics of the Indian squid Uroteuthis duvaucelii in the tropical southeastern Arabian Sea using statolith analysis. The study found that the maximum lifespan of the squid was estimated to be 6 months, with recruitment to the trawl fishery occurring approximately after 2 months of age. The study also estimated the average daily growth rates and age at first maturity for females and males. The findings of this study have important implications for the conservation and management of the U. duvaucelii population.
REGIONAL STUDIES IN MARINE SCIENCE
(2022)
Article
Environmental Sciences
Xue Deng, Gui-Ling Zhang, Ming Xin, Chun-Ying Liu, Wei-Jun Cai
Summary: The study investigated the carbonate system in the southern Yellow-East China Sea area and found changes between spring and summer. The SYS and ECS offshore waters were CO2 sinks in spring and sources in summer, while the Changjiang River plume remained a CO2 sink.
SCIENCE OF THE TOTAL ENVIRONMENT
(2021)
Article
Marine & Freshwater Biology
Yumeng Pang, Chih-Shin Chen, Tomohiko Kawamura, Yoko Iwata
Summary: This study investigates the flexibility of life-history traits in male squids displaying alternative reproductive tactics. The results show that body size, age, growth rate, and gonado-somatic energy allocation of consorts and sneakers in Uroteuthis edulis are influenced by seasonal and geographical factors. Moreover, the ratio of consorts to sneakers varies among different spawning groups and the flexibility of traits is higher in sneakers than in consorts.