Pebsworth Paula A, Morgan Hanna R, Huffman Michael A
Primate Research Institute, Kyoto University, Inuyama, Aichi, Japan.
Primates. 2012 Oct;53(4):345-55. doi: 10.1007/s10329-012-0307-5. Epub 2012 Apr 5.
Global Positioning System (GPS) collars have revolutionized the field of spatial ecology, but to date, few primate studies have used them. We fitted a free-ranging, semi-habituated, juvenile male chacma baboon (Papio hamadryas ursinus) with an automatic self-releasing GPS collar and tracked his movements for 359 days. The collar captured 4254 fixes out of 5719 programmed opportunities, a 74.4 % acquisition rate, suggesting that the collar effectively tracked this baboon in a variety of habitat types. Of the data points captured, 73.7 % were three-dimensional fixes, and of these fixes, 66.9 % were highly accurate, having a dilution of precision of less than four. We calculated home range using three protocols with three estimation methods: minimum convex polygon, fixed kernel-density estimation (KDE), and fixed r local convex hull. Using all data points and the 95 % contour, these methods created home range estimations ranging from 10.8 to 23.1 km(2) for this baboon troop. Our results indicate that the KDE output using all data locations most accurately represented our data set, as it created a continuous home range boundary that excluded unused areas and outlying, potentially exploratory data points while including all seven sleeping sites and a movement corridor. However, home range estimations generated from KDE varied from 15.4 to 18.8 km(2) depending on the smoothing parameter used. Our results demonstrated that the ad hoc smoothing parameter selection technique was a better method for our data set than either the least squares cross-validation or biased cross-validation techniques. Our results demonstrate the need for primatologists to develop a standardized reporting method which documents the tool, screening protocol, and smoothing parameter used in the creation of home range estimations in order to make comparisons that are meaningful.
全球定位系统（GPS）项圈彻底改变了空间生态学领域，但迄今为止，很少有灵长类动物研究使用过它们。我们给一只自由放养、半驯化的幼年雄性东非狒狒（Papio hamadryas ursinus）佩戴了一个自动自释放的GPS项圈，并跟踪它的活动长达359天。在5719次设定的机会中，项圈成功获取了4254个定位点，获取率为74.4%，这表明该GPS项圈能在各种栖息地类型中有效地追踪这只狒狒。在捕获的数据点中，73.7%是三维定位点，其中66.9%的定位精度很高，精度稀释因子小于4。我们使用三种协议和三种估计方法计算了家域：最小凸多边形法、固定核密度估计（KDE）法和固定r局部凸包法。使用所有数据点和95%的等值线，这些方法得出该狒狒群体的家域估计范围为10.8至23.1平方公里。我们的结果表明，使用所有数据位置的KDE输出最准确地代表了我们的数据集，因为它创建了一个连续的家域边界，排除了未使用的区域和外围的、可能用于探索的数据点，同时包括了所有七个睡眠地点和一条移动走廊。然而，根据所使用的平滑参数，由KDE生成的家域估计范围在15.4至18.8平方公里之间。我们的结果表明，对于我们的数据集，临时平滑参数选择技术比最小二乘交叉验证或有偏交叉验证技术更好。我们的结果表明，灵长类动物学家需要开发一种标准化的报告方法，记录创建家域估计时使用的工具、筛选协议和平滑参数，以便进行有意义的比较。
