Populations of African savannah elephants (Loxodonta africana) have been declining due to poaching, human–elephant conflict, and habitat loss. Understanding the causes of these declines could aid in stabilizing elephant populations. We used data from the Great Elephant Census, a 19‐country aerial survey of savannah elephants conducted in 2014 and 2015, to examine effects of a suite of variables on elephant mortality. Independent variables included spatially explicit measures of natural processes and human presence as well as country‐level socioeconomic measures. Our dependent variable was the carcass ratio, the ratio of dead elephants to live plus dead elephants, which is an index of recent elephant mortality. Carcass ratios are inversely proportional to population growth rates of elephants over the 4 yr prior to a survey. At the scale of survey strata (n = 275, median area = 1,222 km²), we found strong negative associations for carcass ratios with vegetation greenness at the time of the survey, overseas development aid to the country, and distance to the nearest international border. At the scale of ecosystems (n = 42, median area = 12,085 km²), carcass ratios increased with drought frequency and decreased with human density and overseas development aid to the country. Both stratum‐ and ecosystem‐scale models explained well under one‐half of the variance in carcass ratios. The differences in results between scales suggest that the drivers of mortality may be scale‐specific and that the corresponding solutions may vary by scale as well.

中文翻译：

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了解非洲大草原大象的死亡率驱动因素。

非洲大草原象（非洲象非洲象）的种群）由于偷猎，人与大象之间的冲突以及栖息地的丧失而一直在下降。了解这些下降的原因可以帮助稳定大象种群。我们使用了2014年和2015年对大草原象进行的19个国家/地区的航空普查大大象普查的数据，研究了一系列变量对大象死亡率的影响。自变量包括自然过程和人类存在的空间明确度量以及国家一级的社会经济度量。我们的因变量是the体比率，即死象与活象的比率加上死象，这是最近大象死亡率的指标。进行调查之前的4年中，体比率与大象的人口增长率成反比。在调查阶层的规模（ñ = 275，中位面积= 1,222 km ²），我们发现car体比率与调查时的植被绿色度，对本国的海外开发援助以及与最近国际边界的距离之间存在强烈的负相关关系。在生态系统规模上（n  = 42，中位面积= 12,085 km ²），car体比率随干旱频率增加而随人的密度和对国家的海外发展援助而下降。str体比例变异的二分之一以下，说明了地层尺度和生态系统尺度模型。量表之间结果的差异表明，死亡率的驱动因素可能是特定于量表的，相应的解决方案也可能因量表而异。