MFishBT: A global database of biogeochemical tags in migratory fish

Humans have long been fascinated by the mysteries surrounding fish migrations, and addressing these puzzling migrations requires large datasets. Biogeochemical tags, including bulk elements and isotopic ratios, are the most accessible biomarkers for powerfully tracking fish migrations. However, standardized datasets on biogeochemical tags for migratory fish research are rarely available, which limits our understanding of the evolutionary origins, driving mechanisms, distribution, migration timing and routes of migratory fishes, as well as to develop conservation strategies and inform management actions. Here, we present MFishBT, a living, open and global database of Migratory Fish’sBiogeochemical Tags. Currently (November 2022), it contains biogeochemical records from 903 studies. Among them, 60% of the studies used element-to-calcium (E/Ca) ratios, 27% used isotopic ratios, and 13% used both tags. The database covers 10,665 field sampling sites (inland 49% vs. marine 51%) around the global major fishing areas and 346 migratory fishes belonging to 31 orders/suborders and 99 families. Seventy-five trace elements and 10 isotopes were detected across various biomineral archives of fish (e.g., otolith, scale, eye lenses and vertebra). E/Ca ratios were examined more frequently than isotopic ratios (64% vs. 36%), led by Sr/Ca, Mg/Ca, Ba/Ca and 87Sr/86Sr, δ13C, δ18O, respectively. The MFishBT comprises 5,494 geo-referenced records with biogeochemical element data detected in the edges of archived tissues. This is the most comprehensive open global database on biogeochemical tags in migratory fish to date, which can serve a variety of needs in scientific research, conservation and management of migratory fish. We encourage researchers to add more datasets to this database in the future. This database is released for non-commercial use only. There are no copyright restrictions, and please cite this paper when using these data, or a subset of these data, for publication.

长久以来，人类始终对鱼类洄游的未解之谜抱有浓厚兴趣，而破解这类复杂的洄游现象亟需大规模数据集支撑。
生物地球化学标记（biogeochemical tags）——包括常量元素与同位素比值——是目前最便于获取的生物标志物，可有效追踪鱼类洄游路径。
然而，目前针对洄游鱼类研究的生物地球化学标记标准化数据集仍极为匮乏，这制约了我们对洄游鱼类演化起源、驱动机制、分布范围、洄游时序与路径的认知，同时也阻碍了洄游鱼类保护策略的制定与管理措施的优化。
为此，我们构建了MFishBT——一个动态开放的全球洄游鱼类生物地球化学标记数据库。
截至2022年11月，该数据库已收录来自903项研究的生物地球化学记录。其中60%的研究采用了元素钙比（element-to-calcium, E/Ca）比值，27%采用了同位素比值，剩余13%同时使用了两类标记。
该数据库覆盖全球主要渔区的10665个野外采样点（内陆采样点占49%，海洋采样点占51%），涵盖隶属于31个目/亚目、99个科的346种洄游鱼类。
研究团队在鱼类的多种生物矿化组织存档中检测到75种微量元素与10种同位素，包括耳石（otolith）、鳞片（scale）、晶状体与脊椎骨（vertebra）等。
相较于同位素比值，元素钙比的检测频次更高（64% vs 36%），其中最常用的分别为锶钙比（Sr/Ca）、镁钙比（Mg/Ca）、钡钙比（Ba/Ca）以及87锶/86锶（87Sr/86Sr）、δ13C、δ18O。
MFishBT包含5494条带有地理坐标的记录，其生物地球化学元素数据均采自存档组织的边缘区域。
截至目前，这是全球范围内最为全面的开放型洄游鱼类生物地球化学标记数据库，可满足洄游鱼类科研、保护与管理领域的多样化需求。
我们呼吁广大科研人员在未来为该数据库补充更多相关数据集。
本数据库仅开放非商业性使用，无版权限制。若将该数据库数据或其子集用于学术发表，请引用本论文。