Understanding of animal responses to dynamic resource landscapes is based largely on research on temperate species with small body sizes and fast life histories. We studied a large, tropical mammal with an extremely slow life history, the Western Bornean orangutan (Pongo pygmaeus wurmbii), across a heterogeneous natural landscape encompassing seven distinct forest types. Our goals were to characterize fluctuations in abundance, test hypotheses regarding the relationship between dispersion dynamics and resource availability, and evaluate how movement patterns are influenced by abiotic conditions. We surveyed abundance in Gunung Palung National Park, West Kalimantan, Indonesia, for 99 consecutive months and simultaneously recorded weather data and assessed fruit availability. We developed a Bayesian hierarchical distance sampling model to estimate population dispersion and assess the roles of fruit availability, rainfall, and temperature in driving movement patterns across this heterogeneous landscape. Orangutan abundance varied dramatically over space and time. Each forest type was important in sustaining more than 40% of the total orangutans on site during at least one month, as animals moved to track asynchronies in fruiting phenology. We conclude that landscape-level movements buffer orangutans against fruit scarcity, peat swamps are crucial fallback habitats, and orangutans’ use of high elevation forests is strongly dependent on abiotic conditions. Our results show that orangutans can periodically occupy putative-sink habitats and be virtually absent for extended periods from habitats that are vitally important in sustaining their population, highlighting the need for long-term studies and potential risks in interpreting occurrence or abundance measures as indicators of habitat importance.

对动物对动态资源景观的反应的理解主要基于对体型小、生活史快的温带物种的研究。我们研究了一种生活史极其缓慢的大型热带哺乳动物，即西婆罗洲猩猩（Pongo pygmaeus wurmbii)，跨越包含七种不同森林类型的异质自然景观。我们的目标是表征丰度的波动，检验关于分散动态与资源可用性之间关系的假设，并评估非生物条件如何影响运动模式。我们连续 99 个月调查了印度尼西亚西加里曼丹岛巴隆山国家公园的丰度，同时记录了天气数据并评估了水果供应情况。我们开发了一个贝叶斯分层距离抽样模型来估计人口分散并评估水果可用性、降雨量和温度在推动这一异质景观的运动模式中的作用。猩猩的数量随空间和时间的变化而显着变化。每种森林类型对于在至少一个月内维持现场猩猩总数的 40% 以上都很重要，因为动物会转移以追踪结果物候的异步性。我们得出的结论是，景观层面的运动缓冲了猩猩对水果稀缺的影响，泥炭沼泽是重要的后备栖息地，猩猩对高海拔森林的利用强烈依赖于非生物条件。我们的结果表明，猩猩可以周期性地占据假定的水槽栖息地，并且实际上长时间不存在对维持其种群至关重要的栖息地，这突出了长期研究的必要性和将发生或丰度措施解释为指标的潜在风险栖息地的重要性。我们得出的结论是，景观层面的运动缓冲了猩猩对水果稀缺的影响，泥炭沼泽是重要的后备栖息地，猩猩对高海拔森林的利用强烈依赖于非生物条件。我们的研究结果表明，猩猩可以周期性地占据假定的水槽栖息地，并且实际上长时间不存在对维持其种群至关重要的栖息地，这突出了长期研究的必要性和将发生或丰度措施解释为指标的潜在风险栖息地的重要性。我们得出的结论是，景观层面的运动缓冲了猩猩对水果稀缺的影响，泥炭沼泽是重要的后备栖息地，猩猩对高海拔森林的利用强烈依赖于非生物条件。我们的研究结果表明，猩猩可以周期性地占据假定的水槽栖息地，并且实际上长时间不存在对维持其种群至关重要的栖息地，这突出了长期研究的必要性和将发生或丰度措施解释为指标的潜在风险栖息地的重要性。