Ecological Insights Into the Extinct Korean Sea Lion (Zalophus japonicus) in Korea Based on Stable Isotope Analysis of Bone Collagen

IF 1.7 3区化学 Q4 BIOCHEMICAL RESEARCH METHODS

Rapid Communications in Mass Spectrometry Pub Date : 2025-10-02 DOI:10.1002/rcm.10140

Yoon Ji Lee, Myung Joon Kim, Ji Seong Kim, Seok Nam Kwak, Sang Heon Lee

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引用次数: 0

Abstract

Rationale

The Japanese sea lion (Zalophus japonicus), once abundant in Japan, Korea, and Russia, went extinct by the mid-20th century due to hunting and environmental change. This study examines the diet and ecological role of Korean Z. japonicus using stable carbon and nitrogen isotope analysis of bone collagen from archaeological and historical contexts.

Methods

Skeletal remains of the extinct Korean sea lion (Z. japonicus) were excavated from Gajae-gull, Ulleungdo, in 2021. A rib bone was analyzed for radiocarbon dating using AMS and calibrated with the Marine20 curve, applying a ΔR correction. Stable isotope analysis of extracted bone collagen (δ¹³C, δ¹⁵N) was performed via EA-IRMS. Isotopic niches of Z. japonicus and modern marine mammals were compared using SIBER in R, with ANOVA and post hoc tests.

Results

Radiocarbon dating of a rib from Gajae-gull, Ulleungdo, indicated burial between 1548 and 1952 cal ad, representing the most recent evidence of Z. japonicus in Korea. Stable isotope analysis revealed dietary shifts from high δ¹⁵N values in the Chulmun periods, indicating consumption of large fish and cephalopods, to lower δ¹⁵N and higher δ¹³C values in the Mumun and historic periods, indicating reliance on coastal mid-trophic prey. Comparisons with modern marine mammals showed clear isotopic niche partitioning.

Conclusions

These findings underscore the dietary flexibility of Korean Z. japonicus and its shifting ecological role in response to changing prey availability and environmental conditions. Future research incorporating additional samples and diverse isotopic markers will enhance paleoecological reconstructions of this extinct species and its historical marine ecosystems.

Abstract Image

查看原文本刊更多论文

基于骨胶原稳定同位素分析的韩国已灭绝朝鲜海狮的生态学认识。

理由：日本海狮（Zalophus japonicus）曾经在日本、韩国和俄罗斯大量存在，但由于狩猎和环境变化，到20世纪中期已经灭绝。本研究通过对考古和历史资料中骨胶原的稳定碳、氮同位素分析，探讨了朝鲜刺参（Z. japonicus）的饮食和生态作用。方法：于2021年在郁陵岛gajae鸥出土了已灭绝的韩国海狮（Z. japonicus）骨骼化石。利用AMS对一根肋骨进行放射性碳定年分析，并用Marine20曲线进行校准，并应用ΔR校正。提取的骨胶原通过EA-IRMS进行稳定同位素（δ13C, δ15N）分析。采用SIBER方法，结合方差分析和事后检验，对日本海参和现代海洋哺乳动物的同位素生态位进行了比较。结果：对郁陵岛Gajae-gull的一根肋骨进行放射性碳定年，表明其埋葬时间在公元1548年至1952年之间，这是在韩国发现的最新证据。稳定同位素分析显示，从丘门时期的高δ15N值，表明大型鱼类和头足类动物的消费，到穆门和历史时期的低δ15N和高δ13C值，表明对沿海中等营养猎物的依赖。与现代海洋哺乳动物的比较显示出明显的同位素生态位划分。结论：这些发现强调了日本刺参的饮食灵活性及其对猎物可得性和环境条件变化的生态作用。未来的研究将结合更多的样本和不同的同位素标记物，加强对这一灭绝物种及其历史海洋生态系统的古生态重建。

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来源期刊

Rapid Communications in Mass Spectrometry 化学-分析化学

CiteScore

4.10

自引率

5.00%

发文量

219

审稿时长

2.6 months

期刊介绍： Rapid Communications in Mass Spectrometry is a journal whose aim is the rapid publication of original research results and ideas on all aspects of the science of gas-phase ions; it covers all the associated scientific disciplines. There is no formal limit on paper length ("rapid" is not synonymous with "brief"), but papers should be of a length that is commensurate with the importance and complexity of the results being reported. Contributions may be theoretical or practical in nature; they may deal with methods, techniques and applications, or with the interpretation of results; they may cover any area in science that depends directly on measurements made upon gaseous ions or that is associated with such measurements.