灰胸薮鹛的栖息地选择与主要致危因素研究

As known, a basic understanding of their habitat selection and the main threatening factors is necessary for conservation of rare and endangered endemic birds. The Emei Shan Liocichla (Liocichla omeiensis) is a rare and endangered babbler endemic to the Mountains of Southwest China. In order to study their habitat selection in multiple scales, a combination of RS and GIS techniques will be used in a thorough survey of the breeding and wintering habitats of this bird. Through this work, we hope to understand the major characteristics of their habitats, to investigate their different spatial utilization of habitats, as well as to find out the key ecological factors that could influence their habitat selection. After collecting enough eco-biological information, we will focus on analyzing some major factors that may threaten the survivorship of Emei Shan Liocichla, such as habitat specialized characteristics, fecundity, interspecific competition and genetic diversity. Based on this study, we hope to explore the main threatening factors of Emei Shan Liocichla.

对于特有珍稀濒危鸟类的保护而言，了解目标物种对特定栖息地的要求和阐明其主要致危因素至关重要。灰胸薮鹛（Liocichla omeiensis）是我国西南山地的一种特有珍稀濒危画眉科鸟类。本项目拟对灰胸薮鹛繁殖期和越冬期的栖息地开展调查，结合RS和GIS技术，对其栖息地选择进行多尺度研究。希望了解灰胸薮鹛栖息地的主要特征，以及灰胸薮鹛对不同空间尺度栖息地的利用性，并找出影响灰胸薮鹛栖息地选择的关键生态因子。在充分收集灰胸薮鹛生态生物学资料的基础上，从栖息地特化、繁殖力、种间竞争及遗传多样性等4个方面展开深入研究，以期探讨该物种的主要致危因素。

本项目以我国西南山地特有珍稀画眉科鸟类灰胸薮鹛（Liocichla omeiensis）为研究对象，对灰胸薮鹛的栖息地选择与主要致危因素开展了系统研究。结果表明：灰胸薮鹛是一种典型的林缘鸟类，偏好灌竹丛和灌草丛生境；灰胸薮鹛与四川方竹（Chimonobambusa szechuanensis）高度伴生，该发现对于揭示物种特有化成因具有重要启示意义；灰胸薮鹛与红嘴相思鸟（Leiothrix lutea）分别采取K-选择与r-选择的生活史对策；灰胸薮鹛与红嘴相思鸟在营巢植被上可能存在激烈竞争，但在巢位高和海拔两个资源轴上发生了显著分离；灰胸薮鹛的繁殖成功率低于同域分布的几种优势画眉科鸟类（红嘴相思鸟、红翅噪鹛Garrulax formosus和棕噪鹛Garrulax poecilorhynchus），但未达到显著差异；灰胸薮鹛的遗传多样性处于中等水平，没有经历过近期的种群瓶颈；大相岭种群和小凉山种群近期的基因流高度不对称；灰胸薮鹛分布区内日益增加的人类经济活动，可能会导致其栖息地（尤其越冬地）加速破碎化甚至部分丧失；估算灰胸薮鹛种群总数量可能不超过2.5万只，近年来每年非法盗猎的灰胸薮鹛数量估计约1000-1500只。经综合分析，认为栖息地丧失与非法捕猎可能是当前灰胸薮鹛种群的主要受胁因素。本研究成果对灰胸薮鹛的种群保护与管理具有重要指导意义。