Data from: Study "Black-necked crane Bhutan (UWICE-MPIAB)"

Movement is a key means by which animals cope with variable environments. As they move, animals construct individual niches composed of the environmental conditions they experience. Niche axes may vary over time and covary with one another as animals make tradeoffs between competing needs. Seasonal migration is expected to produce substantial niche variation as animals move to keep pace with major life history phases and fluctuations in environmental conditions. Here, we apply a time-ordered principal component analysis to examine dynamic niche variance and covariance across the annual cycle for four species of migratory crane: common crane (Grus grus, n = 20), demoiselle crane (Anthropoides virgo, n = 66), black-necked crane (Grus nigricollis, n = 9), and white-naped crane (Grus vipio, n = 9). We consider four key niche components known to be important to aspects of crane natural history: enhanced vegetation index (resources availability), temperature (thermoregulation), crop proportion (preferred foraging habitat), and proximity to water (predator avoidance). All species showed a primary seasonal niche “rhythm” that dominated variance in niche components across the annual cycle. Secondary rhythms were linked to major species-specific life history phases (migration, breeding, and nonbreeding) as well as seasonal environmental patterns. Furthermore, we found that cranes’ experiences of the environment emerge from time-dynamic tradeoffs among niche components. We suggest that our approach to estimating the environmental niche as a multidimensional and time-dynamical system of tradeoffs improves mechanistic understanding of organism–environment interactions.

运动是动物应对多变环境的核心生存策略。动物在移动过程中，会构建由自身经历的环境条件所构成的个体生态位（niche）。当动物在相互竞争的需求间进行权衡时，生态位轴会随时间发生变化并彼此协变。季节性迁徙被认为会引发显著的生态位变异，因为动物会通过移动来适配主要生活史阶段与环境条件的波动。本研究采用时间排序主成分分析（time-ordered principal component analysis），对4种迁徙鹤类的全年周期内动态生态位方差与协方差展开探究：灰鹤（*Grus grus*，n=20）、蓑羽鹤（*Anthropoides virgo*，n=66）、黑颈鹤（*Grus nigricollis*，n=9）以及白枕鹤（*Grus vipio*，n=9）。本研究选取与鹤类自然历史特征紧密相关的4项核心生态位组分：增强型植被指数（enhanced vegetation index，EVI，代表资源可获得性）、温度（关联体温调节）、作物占比（代表偏好觅食生境）以及距水源的距离（关联反捕食行为）。所有鹤类均呈现出主导全年周期内生态位组分方差的核心季节性生态位"节律"。次级节律则与物种特有的主要生活史阶段（迁徙、繁殖与非繁殖期）以及季节性环境模式密切相关。此外，本研究发现鹤类所感知到的环境，源自生态位组分间随时间动态变化的权衡关系。本研究表明，将环境生态位作为权衡关系的多维时间动态系统进行估算的研究方法，可提升我们对生物与环境交互作用的机制性认知。

搜集汇总

背景与挑战

背景概述

该数据集聚焦于黑颈鹤等四种鹤类的迁徙研究，通过时间有序主成分分析方法，分析了它们在年度周期内生态位成分（如植被指数、温度、作物比例和水源距离）的动态变化和协方差，揭示了动物如何通过移动适应环境变化和权衡竞争需求。研究旨在改进对生物与环境相互作用的机制理解。