Migration Route of Sthenoteuthis oualaniensis in the South China Sea Based on Statolith Trace Element Information

Jiangtao Fan; Zhou Fang; Shengwei Ma; Peng Zhang; Xue Feng; Zuozhi Chen

doi:10.3390/ani13182811

Migration Route of Sthenoteuthis oualaniensis in the South China Sea Based on Statolith Trace Element Information

Animals (Basel). 2023 Sep 5;13(18):2811. doi: 10.3390/ani13182811.

Authors

Jiangtao Fan^{1

2}, Zhou Fang³, Shengwei Ma^{1

2}, Peng Zhang^{1

2}, Xue Feng^{1

2}, Zuozhi Chen^{1

2

4}

Affiliations

¹ South China Sea Fisheries Research Institute, Guangzhou 510300, China.
² Key Laboratory for Sustainable Utilization of Open-Sea Fishery, Ministry of Agriculture and Rural Affairs, Guangzhou 510300, China.
³ College of Marine Sciences, Shanghai Ocean University, Shanghai 201306, China.
⁴ Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, China.

Abstract

Sthenoteuthis oualaniensis (Lesson, 1830) is a pelagic species with a complex population structure and wide migration range. The trace elements in statoliths are effective indicators for reconstructing the life history of an individual. In this study, the trace elements in statoliths were determined via laser ablation inductively coupled plasma mass spectrometry, and a multiple regression tree (MRT) model was used to trace the migration of S. oualaniensis and identify its potential habitats in the South China Sea. Na, Mg, Fe, Sr, and Ba were the effective trace elements, with significant differences found among stocks (p < 0.05). The MRT was divided into five clusters representing five life history stages. The Mg:Ca and Sr:Ca ratios decreased initially and increased thereafter, and the Mg:Ca, Sr:Ca, and Ba:Ca ratios differed significantly among the stages of the life history in each stock (p < 0.05). The hatching water temperatures for the winter and summer-autumn spawning populations were 28.05-28.88 °C (temperature at 25 m) and 27.15-27.92 °C (temperature at 25 m). The winter stock hatched in the southern South China Sea, and the larvae then migrated northwest during the summer monsoon. The summer-autumn stocks hatched in the northern South China Sea, and the larvae migrated southward under the mesoscale closed anticyclonic circulation in the northern South China Sea. These results provide insight into the migration of S. oualaniensis in the South China Sea.

Keywords: South China Sea; Sthenoteuthis oualaniensis; migration route; statolith; trace element.

Grants and funding

This research was funded by the Major Projects of Basic and Applied Basic Research Programs in Guangdong Province (2019B030302004), the Key Research and Development Project of Guangdong Province (2020B1111030001), the Central Public-Interest Scientific Basal Research Fund (2020TD05), and the Fund of Key Laboratory of Open-Sea Fishery Development, Ministry of Agriculture, China (LOF 2021-01).