新疆卡拉麦里山有蹄类野生动物自然保护区夏季蒙古野驴适宜生境与种群数量评估

蒙古野驴(Equus hemionus hemionus)是亚洲内陆荒漠、半荒漠和荒漠草原区域的代表性物种。开展其种群数量调查和适宜生境研究可以为该物种的保护管理提供科学决策依据。本研究于2018和2019年夏季,采用样线法对新疆卡拉麦里山有蹄类自然保护区蒙古野驴的地理分布现状和种群数量进行了调查,采用Distance 7.0软件估算了蒙古野驴的种群密度和数量,并通过MaxEnt模型分析筛选环境变量,确定保护区蒙古野驴的适宜生境及其主要影响因子。结果表明: 调查中发现蒙古野驴718群、共4782头,有效分布位点363个。夏季蒙古野驴适宜生境主要位于保护区的中东部,面积为6737.5 km²,占整个保护区的45.4%,估算保护区夏季蒙古野驴的种群密度为(0.5±0.1)头·km^-2,保护区内蒙古野驴种群数量为(3246±575)头。MaxEnt模型的预测准确性较高,AUC的平均值为0.890。影响蒙古野驴分布的主要环境因子依次为: 距水源点距离、植被类型、距人类活动区距离、距G216国道的距离、海拔和最干季的降水量。最后,从水源点保护、核心区调整、野生动物通道监测和交通建设4个方面,对蒙古野驴种群的保护管理提出了建议。

Suitable summer habitat of the khulan in the Mt. Kalamaili Ungulate Nature Reserve and estimation of its population

The khulan (Equus hemionus hemionus) is a representative species in desert, semi-desert and desert steppe in Asia. The estimation of suitable habitat and population density of khulan can provide scientific decision-making basis for the conservation management. We investigated the distribution and population density of khulan in the Mt. Kalamaili Ungulate Nature Reserve in Xinjiang during May-August in 2018 and 2019, using the line transect method. The khulan population density, number and the encounter rate were estimated by the Distance 7.0 software, and through the MaxEnt model analysis and combining environmental variables, we assessed the most suitable habitats and main influencing factors. In total, we recorded 4782 individuals from 718 groups and 363 effective occurrences. Our results showed that the suitable summer habitat covered an area of 6737.5 km², accounting for 45.4% of the total reserve area and located mainly in the central and eas-tern parts of the reserve. We estimated that the density of the summer khulan population was (0.5±0.1) individuals·km^-2 and the total khulan population were (3246±575) individuals in the Mt. Kalamaili Ungulate Nature Reserve. The prediction accuracy of MaxEnt model was relatively high, with an average AUC of 0.890. The results of the Jackknife test showed that the distance to water sources, vegetation type, distance to human interference, distance to national highway G216, altitude, and precipitation of driest areas were the most important factors affecting the habitat suitability for khulan. For improving the protection of the khulan population in this reserve, we suggested strengthen the protection of water sources, adjust the core areas, monitor wildlife passages, and enhance traffic construction.