Ghimirey Yadav, Acharya Raju, Mintz Jeffrey
Department of Wildlife Ecology and Conservation University of Florida Gainesville Florida USA.
Friends of Nature Kathmandu Nepal.
Ecol Evol. 2024 Nov 18;14(11):e70572. doi: 10.1002/ece3.70572. eCollection 2024 Nov.
Species richness is an important metric used for undertaking conservation management decisions. However, species richness estimates are influenced by species detection probabilities, with potential to entirely overlook species during surveys. Occupancy models which account for imperfect detection provide unbiased estimates, ensuring accurate estimates of richness. We carried out a camera trap survey in the mountains of north-central Nepal during 2017 and documented a total of 21 mammal species. Here, we used multi-species occupancy models within a Bayesian hierarchical framework to reassess our initial species richness estimate and to understand the influence of environmental covariates on occupancy and species richness of mammals in the area. Our model estimated the mean species richness was ~26 species (95% CRI: 21-36 species), suggesting we might have missed ~5 species during the survey. The mean probability of occupancy and detection of mammal species were estimated to be and 0.02 (95% CRI:0.01-0.03) respectively. Mammalian species richness of the area had an anticipated positive relationship with tree canopy cover though its positive relationship with anthropogenic disturbance was surprising . Mammalian species richness had a quadratic relationship with elevation as is expected. This research contributes to baseline information of the mammal community ecology in north-central Nepal and supports the need for future multi-season surveys to understand the influence of temporal factors on mammalian community and species richness in the area.
物种丰富度是用于做出保护管理决策的一项重要指标。然而,物种丰富度估计会受到物种检测概率的影响,在调查过程中有可能完全忽略某些物种。考虑到不完全检测情况的占有率模型能够提供无偏估计,确保对丰富度的准确估计。2017年我们在尼泊尔中北部山区开展了一次相机陷阱调查,共记录了21种哺乳动物。在此,我们在贝叶斯层次框架内使用多物种占有率模型,重新评估我们最初的物种丰富度估计,并了解环境协变量对该地区哺乳动物占有率和物种丰富度的影响。我们的模型估计平均物种丰富度约为26种(95%可信区间:21 - 36种),这表明我们在调查过程中可能遗漏了约5种物种。哺乳动物物种的平均占有率和检测概率估计分别为 和0.02(95%可信区间:0.01 - 0.03)。该地区哺乳动物的物种丰富度与树冠覆盖度呈预期的正相关关系,不过其与人为干扰的正相关关系令人惊讶。哺乳动物物种丰富度与海拔呈预期的二次关系。这项研究为尼泊尔中北部哺乳动物群落生态学提供了基线信息,并支持未来开展多季节调查以了解时间因素对该地区哺乳动物群落和物种丰富度影响的必要性。