Data from: The distribution and numbers of cheetah (Acinonyx jubatus) in southern Africa

Assessing the numbers and distribution of threatened species is a central challenge in conservation, often made difficult because the species of concern are rare and elusive. For some predators, this may be compounded by their being sparsely distributed over large areas. Such is the case with the cheetah Acinonyx jubatus. The IUCN Red List process solicits comments, is democratic, transparent, widely-used, and has recently assessed the species. Here, we present additional methods to that process and provide quantitative approaches that may afford greater detail and a benchmark against which to compare future assessments. The cheetah poses challenges, but also affords unique opportunities. It is photogenic, allowing the compilation of thousands of crowd-sourced data. It is also persecuted for killing livestock, enabling estimation of local population densities from the numbers persecuted. Documented instances of persecution in areas with known human and livestock density mean that these data can provide an estimate of where the species may or may not occur in areas without observational data. Compilations of extensive telemetry data coupled with nearly 20,000 additional observations from 39 sources show that free-ranging cheetahs were present across approximately 789,700 km2 of Namibia, Botswana, South Africa, and Zimbabwe (56%, 22%, 12% and 10% respectively) from 2010 to 2016, with an estimated adult population of 3,577 animals. We identified a further 742,800 km2 of potential cheetah habitat within the study region with low human and livestock densities, where another ∼3,250 cheetahs may occur. Unlike many previous estimates, we make the data available and provide explicit information on exactly where cheetahs occur, or are unlikely to occur. We stress the value of gathering data from public sources though these data were mostly from well-visited protected areas. There is a contiguous, transboundary population of cheetah in southern Africa, known to be the largest in the world. We suggest that this population is more threatened than believed due to the concentration of about 55% of free-ranging individuals in two ecoregions. This area overlaps with commercial farmland with high persecution risk; adult cheetahs were removed at the rate of 0.3 individuals per 100 km2 per year. Our population estimate for confirmed cheetah presence areas is 11% lower than the IUCN’s current assessment for the same region, lending additional support to the recent call for the up-listing of this species from vulnerable to endangered status.评估受威胁物种的数量与分布是保护生物学领域的核心挑战之一，而受关注物种往往兼具稀有性与隐匿性，常令此类评估工作举步维艰。对于部分食肉动物而言，其大范围稀疏分布的特性更会加剧评估难度，猎豹（Acinonyx jubatus）正是典型代表。国际自然保护联盟红色名录（IUCN Red List）流程具备征求意见、民主透明、应用广泛的特点，且近期已完成该物种的评估工作。本文在此既有流程基础上提出补充方法，并提供量化研究路径，可为后续评估提供更精细的参考基准与对比依据。猎豹虽为评估工作带来诸多挑战，却也提供了独特的研究契机：其外形上镜，可通过众包渠道收集数千条观测记录；同时因捕食家畜而遭人类迫害，据此可通过迫害事件的数量估算当地种群密度。在已知人类与家畜密度的区域中，已记录的迫害事件数据，可用于推断无直接观测数据区域内猎豹的适宜分布范围。研究团队整合了大量遥测数据与来自39个来源的近20000条额外观测记录，结果显示：2010至2016年间，自由栖息的猎豹分布于纳米比亚、博茨瓦纳、南非与津巴布韦境内约789700平方千米的区域（占比分别为56%、22%、12%与10%），估算成年种群数量为3577只。此外，研究团队在研究区域内识别出742800平方千米的潜在猎豹栖息地，这些区域人类与家畜密度较低，或可承载约3250只猎豹。与诸多既往估算不同，本文公开了全部研究数据，并明确给出猎豹确切分布或大概率无分布的区域信息。尽管本次采集的数据多来自游客密集的保护区，我们仍强调从公共来源收集数据的重要价值。南部非洲存在一处连续的跨境猎豹种群，是目前已知全球规模最大的猎豹种群。研究发现，约55%的自由栖息个体集中于两个生态区，这表明该种群的受威胁程度高于此前认知。该区域与迫害风险较高的商业农田重叠，成年猎豹的人为移除率约为每100平方千米每年0.3只。本次针对确认有猎豹分布区域的种群估算结果，比国际自然保护联盟（IUCN）针对同一区域的当前评估低11%，进一步支持了近期将该物种从易危升级为濒危的呼吁。