Abstract: Objective To provide a scientific statistical method for accurate determination of the seasonal density of plague host animals. Methods The data of Spermophilus dauricus were collected using Excel 2013 software from a natural plague focus monitoring site in Kangbao pasture in Hebei province, China from April to October in 2015-2019. The seasonal density of S. dauricus was analyzed by the concentration method. Results From 2015 to 2019, a total of 240 S. dauricus individuals were captured in an area of 490 hm², and the mean annual density in Kangbao pasture was 0.49 inds/hm². The highest density was 0.66 inds/hm² in summer, followed by 0.37 inds/hm² in Autumn and 0.18 inds/hm² in winter. The highest density was recorded in April 2016 (2.53 inds/hm²), followed by 1.94 inds/hm² in April 2015 and 1.07 inds/hm² in July 2018. Analysis with the concentration method showed M=0.330 5, suggesting that the density of S.dauricus varied across seasons. Conclusion The concentration method can accurately determine the seasonal density of S. dauricus as a plague host, and the highest density is found in summer, followed by autumn.

Key words: Concentration, Spermophilus dauricus, Hebei, Plague

摘要： 目的 为准确判定鼠疫宿主动物密度季节性提供科学的统计方法。方法 采用Excel 2013软件对河北省鼠疫自然疫源地康保牧场鼠疫监测点2015－2019年每年4－10月达乌尔黄鼠监测数据进行统计；运用集中度法对达乌尔黄鼠密度季节性进行分析。结果 2015－2019年在河北省康保牧场达乌尔黄鼠鼠疫疫源地共调查面积490 hm²，捕鼠240只，均为达乌尔黄鼠，年平均密度为0.49只/hm²；密度最高的季节在夏季，为0.66只/hm²，其次为秋季和冬季，分别为0.37和0.18只/hm²；密度最高月份为2016年4月，达2.53只/hm²，其次为2015年4月和2018年7月，分别为1.94和1.07只/hm²；集中度（M）法研究确定M=0.330 5，即说明达乌尔黄鼠密度变化具有一定的季节性。结论 集中度法可以比较准确地分析鼠疫宿主动物达乌尔黄鼠密度季节性，其密度最高的季节在夏季，其次是秋季。

关键词: 集中度, 达乌尔黄鼠, 河北, 鼠疫