Data underlying the paper "Demographic structure of African elephant population is a reflection of past drought duration and intensity"

The free-ranging elephants in Amboseli have been monitored continuously since 1972, and records of over 3000 individually known elephants are maintained in the Amboseli Elephant Research Project’s (AERP) database (Moss 2001). Births and mortalities of elephants between 1972 and 1975 are known with a precision of 3-6 months, and from 1976 with a precision of 2 weeks to 3 months (Lee et al. 2013). We used data collected until 2012. We categorized elephants in age classes as young calves (0-12 months), older calves (13-24 months), immatures (2-8 years), young adults (9-24 years), prime reproductive adults (25-49) and old adults (50+).

自1972年起，安博塞利（Amboseli）的自由放养象群便得到持续监测，安博塞利大象研究项目（Amboseli Elephant Research Project, AERP）的数据库中留存了超过3000头经个体识别的大象的完整记录（Moss 2001）。1972年至1975年间，大象的出生与死亡事件记录精度可达3至6个月；1976年起，该类记录的精度提升至2周至3个月（Lee et al. 2013）。本研究使用了截至2012年收集的全部相关数据。我们将大象按年龄划分为以下类别：幼龄幼崽（0至12月龄）、大龄幼崽（13至24月龄）、未成熟个体（2至8岁）、青年成年个体（9至24岁）、繁殖盛期成年个体（25至49岁）以及老年成年个体（50岁及以上）。