Durrell Institute of Con servation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, UK.
Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Kota Kinabalu, Sabah, Malaysia.
Am J Primatol. 2019 Aug;81(8):e23030. doi: 10.1002/ajp.23030. Epub 2019 Jul 21.
The conversion of forest to agriculture continues to contribute to the loss and fragmentation of remaining orang-utan habitat. There are still few published estimates of orang-utan densities in these heavily modified agricultural areas to inform range-wide population assessments and conservation strategies. In addition, little is known about what landscape features promote orang-utan habitat use. Using indirect nest count methods, we implemented surveys and estimated population densities of the Northeast Bornean orang-utan (Pongo pygmaeus morio) across the continuous logged forest and forest remnants in a recently salvage-logged area and oil palm plantations in Sabah, Malaysian Borneo. We then assessed the influence of landscape features and forest structural metrics obtained from LiDAR data on estimates of orang-utan density. Recent salvage logging appeared to have a little short-term effect on orang-utan density (2.35 ind/km ), which remained similar to recovering logged forest nearby (2.32 ind/km ). Orang-utans were also present in remnant forest patches in oil palm plantations, but at significantly lower numbers (0.82 ind/km ) than nearby logged forest and salvage-logged areas. Densities were strongly influenced by variation in canopy height but were not associated with other potential covariates. Our findings suggest that orang-utans currently exist, at least in the short-term, within human-modified landscapes, providing that remnant forest patches remain. We urge greater recognition of the role that these degraded habitats can have in supporting orang-utan populations, and that future range-wide analyses and conservation strategies better incorporate data from human-modified landscapes.
森林转为农业用地仍在继续导致剩余猩猩栖息地的丧失和碎片化。在这些经过大规模改造的农业区，仍很少有关于猩猩密度的发表估计值，这些数据无法为全范围的种群评估和保护策略提供信息。此外，人们对促进猩猩栖息地利用的景观特征知之甚少。我们使用间接巢计数方法，在沙巴的马来西亚婆罗洲，对最近经过采伐补救的地区和油棕种植园的连续采伐森林和森林残余物中的东北婆罗洲猩猩（Pongo pygmaeus morio）进行了调查并估算了种群密度。然后，我们评估了来自 LiDAR 数据的景观特征和森林结构指标对猩猩密度估计的影响。最近的采伐补救似乎对猩猩密度（2.35 只/km²）产生了短期的影响，与附近正在恢复的采伐森林（2.32 只/km²）相似。在油棕种植园中，猩猩也存在于森林残余斑块中，但数量明显较少（0.82 只/km²），远低于附近的采伐森林和采伐补救区。密度受冠层高度的变化强烈影响，但与其他潜在的协变量无关。我们的研究结果表明，至少在短期内，猩猩目前存在于人类改造的景观中，只要剩余的森林斑块仍然存在。我们敦促更多地认识到这些退化栖息地在支持猩猩种群方面可以发挥的作用，并且未来的全范围分析和保护策略更好地纳入来自人类改造景观的数据。
