关键词: 黑线姬鼠, 绝对密度, 越冬, 年龄组成

Abstract: From Nov.1984 to Mar.1985 the authors studied the approximate density of Apodemus agrarius and its overwintering age group by excavating its nests in about 100 hectares of hillock and bow-lying land in Huainan,Anhui Province. The excavating covered 88.8 hectares of cropland and 7.2 hectares of bank of carth alongside the cropland. 76 specimens were collected, of which 70 were caught of the side area and only 6 were caught inside the cropland. The average density of Apodemus agrarius per hectare was 0.86. The average number for the inside of the cropland was 0.07 and the average number for the alongside area was 9.72. The search also covered 2.2 hectares of ridge area with the result of 42 specimens caught. The average density for this area was 19.09. The author searched 17 haystacks near the cropland which occupied 0.102 hectare with the result of 32 Apodemus agrarius caught. The average density for haystack per hectare was 313.7. For the low-lying land a total number of 308 Apodemus agrarius were caught with the average density of 3.62 per hectare. 7.04 hectare of ditch area were searched with the result of 180 specimens caught. The average density number was 25.57 per hectare and 23 haystacks near the ditch area were searched. They occupied 0.138 hectare and 96 specimens were caught. The average density was 695.7 per hectare. The study were made from Nov. Till the next Mar. Total 523 specimens were caugh from 162 nests. It was found the overwintering age group of Apodemus agrarius was mainly made up by sub-adult and adult Ⅰ individuals. These two constituted 62.91 percent of overwintering population.