种群生存力分析（Population viability analysis，PVA）是保护生物学的基础理论。PVA在下降种群保护方面还未形成成熟和系统的理论和方法，导致其在鱼类保护中的应用明显少于哺乳类、鸟类、爬行类。长江上游特有鱼类受到建坝、捕捞等人类活动的严重不利影响。但是，目前还没有特有鱼类的保护生物学研究。本研究拟以洄游型特有鱼类长薄鳅和定居型特有鱼类厚颌鲂为对象，通过对物种种群生态学、生物学、早期生活史特征的调查，收集数据建立种群生存力分析模型，模型关联环境条件对种群的影响，分析特有鱼类种群灭绝风险、最小可存活种群，评估影响种群生存的关键环境因子。同时，比较不同生态类群在一定环境条件的种群动态，探讨各生态类群面对环境压力的种群变化特征，提出特有鱼类种群保护措施，建立鱼类种群生存力分析的技术体系，促进种群生存力分析应用和理论的发展。

Population viability analysis (PVA) is the basic theory of conservation biology. There are no the comprehensive theory and method for the declining population, such as fish, leading to the PVA studies of fish so less than those of mammals, birds, reptiles. At present, the endemic fish of the upper Yangtze River are severely influenced by the human activities, such as damming and overfishing. However, we have few studies on the conservation biology of the endemici fish. In this study, we aim to construct the Individual-base models, which are connected with the environmental factors, of two endemic fish, Leptobotia elongate and Megalobrama pellegrini, based on their biology, population ecology, and early life history, in order to quantify the extinction risk of the populations and minimum viable populations and assess the key environmental factors impacting the population persistence. Moreover, through comparing the population dynamics of the different ecological groups, we characterized the change of the population size of each ecological group under the environmental pressure. As a result, the conservation tactics will be suggested. And we would like to establish the technical system of population viability analysis of fish for developing application and theory of PVA.