Summarising biometrics from the SAFRING database for southern African birds

Biometrics form a key characteristic of a species. Here, we provide a summary of biometrics held by the South African Bird Ringing Scheme (SAFRING), which was initiated in 1948, including measures of mass and lengths of the tarsus, head, culmen, tail and wing. We include all species in southern Africa for which there was sufficient data. Accordingly, we present biometric data for 674 of the 904 southern African bird species. We also investigated whether there were sex-specific differences for each species, and provide summaries for species where values significantly differed between the sexes. We found 376 species with significant sex-specific differences for at least one measure (e.g. mass). Although SAFRING holds data entries for many ringed individuals, a sizeable proportion of the entries was not useable as biometric data. Therefore, in this article, we aim to: 1) present a complete, standardised reference of summarised biometric data for the birds of southern Africa; 2) provide ringers with benchmark values that could guide data-capturing; 3) identify data-deficient species; and 4) highlight the importance of collecting and capturing biometric data carefully and consistently.

生物测量数据（biometrics）是物种的核心特征之一。本文整理了南非鸟类环志计划（South African Bird Ringing Scheme, SAFRING）所留存的生物测量数据汇总，该计划于1948年启动，涵盖体重、跗跖长、头长、嘴峰长、尾长以及翼长等多项测量指标。本次研究纳入了南部非洲所有具备充足有效数据的鸟类物种，最终收录了904种南部非洲鸟类中的674种的生物测量数据。此外，本研究针对各物种是否存在性别特异性差异开展了分析，并为两性间测量值存在显著差异的物种提供了汇总结果。研究显示，共有376种鸟类至少在一项测量指标（如体重）上存在显著的性别差异。尽管南非鸟类环志计划收录了大量环志个体的记录条目，但其中相当一部分无法作为有效生物测量数据使用。鉴于此，本文旨在达成以下目标：1） 提供一套完整、标准化的南部非洲鸟类生物测量数据汇总参考资料；2） 为环志人员提供可指导数据采集的基准参考值；3） 识别出数据不足的物种；4） 强调严谨且持续地采集并记录生物测量数据的重要性。