The response of mixed-species bird flocks to anthropogenic disturbance and elevational variation in southwest China

Avian mixed-species flocks (MSFs) are an important example of species interactions threatened by the biodiversity crisis. They are found throughout the world in forested habitats, but are generally reduced in size or frequency by human disturbance. In southern China, a unique MSF system has been described that is led by fulvettas (Alcippe morrisonia, A. hueti and A. davidi). Our objective was to understand how this system is distributed across elevational gradients, especially moving west into the Hengduan Mountains, and how it responds to human disturbance. We sampled leadership and composition of 375 MSFs over 2 years in and surrounding 5 nature reserves in Guangxi Zhuang Autonomous Region and Yunnan Province, with transects placed in different land use types – protected forest, buffer areas, or agriculture – and ranging from 400 to 3200 m. We also sampled birds outside of MSFs. We found MSFs led by fulvettas (A. fratercula and A. davidi) in forests across the region up to 2900 m. Ele...

鸟类混合物种群（mixed-species flocks, MSFs）是生物多样性危机下受威胁的物种互作典型范例。该类群广泛分布于全球各类森林生境，但通常会因人类活动干扰而出现种群规模缩减或出现频率下降。在中国南方，已有研究报道了一种独特的混合物种群系统，其领群物种为雀鹛属（*Alcippe*）的*Alcippe morrisonia*、*A. hueti*及*A. davidi*。本研究旨在明确该系统沿海拔梯度的分布格局，尤其是其向西延伸至横断山脉的分布情况，以及该系统对人类活动干扰的响应模式。研究团队于两年时间内，在广西壮族自治区与云南省的5处自然保护区及其周边区域，对375个混合物种群的领群物种与群落组成开展了采样调查；样带设置覆盖了保护林、缓冲区与农田等不同土地利用类型，海拔跨度为400米至3200米。此外，研究团队还对未参与混合物种群的鸟类进行了采样。研究结果显示，在本区域海拔2900米以下的森林生境中，均存在由雀鹛（*A. fratercula*与*A. davidi*）领群的混合物种群。Ele……