This month’s cover image shows a female flatback sea turtle Natator depressus leaving a nesting beach, fitted with an accurate Fastloc‐GPS tag. In tracking studies it is often difficult to determine the sample sizes necessary to describe the spatial distribution of a population. In this issue, Shimada et al. examine existing approaches, highlight caveats and propose a new method to better assess appropriate sample sizes. Large datasets of movements of flatback turtles are analysed to illustrate this new method, which has broad applicability for the post‐hoc validation of sample sizes of tracking data across a wide range of taxa, populations and life‐history stages of animals. Code for the analysis is compiled in the open‐access R package SDLfilter

中文翻译：

---

封面图片和发行信息

本月的封面图片显示了一只雌性平背海龟Natator depressus离开巢穴海滩，上面贴有准确的Fastloc-GPS标签。在追踪研究中，通常难以确定描述种群空间分布所必需的样本数量。在这个问题上，岛田等。检查现有方法，强调警告，并提出一种新方法，以更好地评估适当的样本量。分析了平背海龟运动的大型数据集以说明这种新方法，该方法广泛适用于动物的各种分类，种群和生活史阶段的跟踪数据样本大小的事后验证。分析代码在开放访问R包SDLfilter中进行编译