三江源国家级自然保护区内云塔村雪豹种群动态

种群监测可为物种研究和保护提供关键信息和依据。雪豹(Panthera uncia)作为亚洲高山生态系统的顶级捕食者和旗舰种, 一直是研究和保护的重点, 但其难以到达的栖息地、隐秘的行踪和广阔的家域使其监测工作开展难度较大, 雪豹种群动态研究较为匮乏。本研究在2013年10月至2019年1月期间, 使用当地社区维护的红外相机, 监测三江源国家级自然保护区通天河沿保护分区内青海省玉树州哈秀乡云塔村雪豹种群的密度和动态, 共识别出35只雪豹个体。基于数据质量较好的2015、2016、2017年连续3年的红外相机数据各年截取3个月数据, 使用空间标记-重捕模型估算种群数量和密度, 发现当地雪豹种群和成年个体密度基本维持稳定, 种群增长率为1.02, 但监测期间雪豹个体更替明显, 平均个体更替率为0.44, 并且围绕两片雪豹核心利用区域发生了领域取代。推测雪豹种群具有较多个体更替和领域取代是因为种群处在雪豹潜在扩散通道上, 或调查范围未覆盖完整种群。本研究是国内首次对雪豹进行较为长期的种群动态监测和分析, 研究结果体现了动态监测的重要性, 也显示出以当地社区为主体监测哺乳动物种群的可能性。     

祁连山国家公园青海片区雪豹栖息地适宜性评价

雪豹是全球生物多样性保护的旗舰物种,精准评估雪豹栖息地质量可为其种群保护提供科学参考。本文选取地形、气候、植被类型和人为干扰等环境因子,采用景观连接度和MaxEnt模型两种方法,对祁连山国家公园青海片区雪豹栖息地质量进行评价。结果表明：高适宜栖息地主要分布在研究区的西部和中部,适宜面积占青海片区总面积的71.8%～77.5%,两种方法预测的适宜栖息地重叠区为8 979.1 km2,占青海片区总面积的56.7%;39.8%～43.3%的适宜栖息地分布在一般控制区,56.7%～60.2%的适宜栖息地分布在核心保护区;疏勒河源区适宜栖息地面积最多,石羊河源区适宜栖息地面积最少,黑河源区适宜栖息地面积占比最高,约为77.1%～91.8%。适宜栖息地面积整体呈现自东向西递增的趋势。一般控制区分布有较大面积的雪豹栖息地,人类活动将是一般控制区雪豹栖息地的潜在威胁。本研究对优化雪豹就地保护措施提供科学借鉴与参考。     

天山中部雪豹栖息地适宜性研究初报

栖息地丧失和破碎化是许多濒危物种面临的主要威胁,对于分布在高原山地的濒危物种雪豹亦是如此。为了更好地了解天山雪豹的分布情况和栖息地质量,2018年11月至2019年6月,我们在天山中部借助红外相机开展野外调查,调查面积2 425 km²,共获得78个雪豹的出现位点。利用8个物种分布模型对雪豹在此地的生境选择建模,综合结果表明,崎岖度和海拔是影响雪豹分布的主要因素,其中崎岖度大于70和海拔1 700~2 900 m是雪豹出现频率最高的地区。集成模型空间预测显示大部分适宜栖息地集中于乌苏市以东至板房沟分局管辖地区。本研究通过野外调查和模型分析获得了天山中部雪豹的分布区域及环境因子对其的影响,为天山雪豹保护及跨境合作提供科学的数据支撑。     

Nondetection sampling bias in marked presence‐only data

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