Poaching on private land may potentially significantly deplete the rhino population yet is poorly studied. We focus on temporal patterns in poaching events, whether there is any evidence of targeting of specific categories of rhino (in relation to species, sex and age) and whether these patterns in poaching show any trends over time. Using rhino owner and (mainstream and social) media reports, we complied a database of private land poaching events between 2003 and 2017. Patterns in poaching activity were broadly consistent over time. Poaching is most likely at night, under the full moon, and close to the property perimeter. Whilst there was no consistent temporal pattern in poaching, there was evidence of increased poaching during the weekend (Friday–Sunday) compared to weekdays (Monday–Thursday) in 2017. Prioritising rhino protection efforts at these times may therefore be the most efficient use of limited resources. Because there is no evidence that poachers selectively target rhinos, efforts undertaken by private owners to protect specific individuals or groups may be ineffective. Our research also highlighted key data that were currently not clearly recorded, including collateral calf deaths and lost pregnancies, which may have a significant impact on the scale of the rhino poaching problem.

中文翻译：

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南非私人土地上的犀牛偷猎活动模式

在私人土地上偷猎可能会严重消耗犀牛数量，但研究却很少。我们关注盗猎事件中的时间模式，是否有针对特定种类犀牛（与物种，性别和年龄有关）的证据，以及这些盗猎模式是否随时间推移呈现出任何趋势。利用犀牛所有者和（主流和社交）媒体报道，我们汇编了2003年至2017年间私人土地偷猎事件的数据库。随着时间的推移，偷猎活动的模式基本保持一致。盗猎最有可能在晚上，满月之下和靠近酒店周边的地方进行。尽管偷猎没有统一的时间规律，但有证据表明，与2017年的工作日（周一至周四）相比，周末（周五至周日）的偷猎活动有所增加。因此，在这些时候优先保护犀牛的工作可能是对有限资源的最有效利用。因为没有证据表明偷猎者有选择地针对犀牛，所以私人所有者为保护特定个人或群体而做出的努力可能是无效的。我们的研究还着重指出了目前尚未清楚记录的关键数据，包括小腿附带的死亡和怀孕损失，这可能对犀牛偷猎问题的规模产生重大影响。