Duangchantrasiri Somphot, Jornburom Pornkamol, Jinamoy Sitthichai, Pattanavibool Anak, Hines James E, Arnold Todd W, Fieberg John, Smith James L D
Wildlife Research Division Department of National Parks, Plant, and Wildlife Conservation Bangkok Thailand.
University of Minnesota Saint Paul Minnesota.
Ecol Evol. 2019 Feb 18;9(5):2449-2458. doi: 10.1002/ece3.4845. eCollection 2019 Mar.
Despite conservation efforts, large mammals such as tigers () and their main prey, gaur (), banteng (), and sambar (), are highly threatened and declining across their entire range. The only large viable source population of tigers in mainland Southeast Asia occurs in Thailand's Western Forest Complex (WEFCOM), an approximately 19,000 km landscape of 17 contiguous protected areas.We used an occupancy modeling framework, which accounts for imperfect detection, to identify the factors that affect tiger distribution at the approximate scale of a female tiger's home range, 64 km, and site use at a scale of 1-km. At the larger scale, we estimated the proportion of sites at WEFCOM that were occupied by tigers; at the finer scale, we identified the key variables that influence site-use and developed a predictive distribution map. At both scales, we examined key anthropogenic and ecological factors that help explain tiger distribution and habitat use, including probabilities of gaur, banteng, and sambar occurrence from a companion study.Occupancy estimated at the 64-km scale was primarily influenced by the combined presence of all three large prey species, and 37% or 5,858 km of the landscape was predicted to be occupied by tigers. In contrast, site use estimated at the scale of 1 km was most strongly influenced by the presence of sambar.By modeling occupancy while accounting for imperfect probability of detection, we established reliable benchmark data on the distribution of tigers in WEFCOM. This study also identified factors that limit tiger distributions; which managers can then target to expand tiger distribution and guide recovery elsewhere in Southeast Asia.
尽管采取了保护措施，但老虎等大型哺乳动物及其主要猎物白肢野牛、爪哇野牛和水鹿在其整个分布范围内仍受到高度威胁且数量在减少。东南亚大陆唯一现存的大型老虎种群位于泰国西部森林复合体（WEFCOM），这是一个由17个相邻保护区组成的约19000平方公里的区域。我们使用了一个考虑到不完全检测情况的占用模型框架，来确定在雌性老虎家域近似尺度（64公里）以及1公里尺度上影响老虎分布的因素。在较大尺度上，我们估计了WEFCOM中被老虎占据的地点比例；在较精细尺度上，我们确定了影响地点使用的关键变量，并绘制了预测分布图。在这两个尺度上，我们都研究了有助于解释老虎分布和栖息地使用情况的关键人为因素和生态因素，包括来自一项配套研究的白肢野牛、爪哇野牛和水鹿出现的概率。在64公里尺度上估计的占用情况主要受所有三种大型猎物物种共同存在的影响，预计该区域有37%或5858平方公里的区域被老虎占据。相比之下，在1公里尺度上估计的地点使用情况受水鹿存在的影响最大。通过在考虑不完全检测概率的情况下对占用情况进行建模，我们建立了关于WEFCOM中老虎分布的可靠基准数据。这项研究还确定了限制老虎分布的因素，管理人员可据此确定目标以扩大老虎分布范围，并为东南亚其他地区的老虎恢复工作提供指导。
