The ecological research of Gansu Zoker (Myospalax callous) was carried out in Xiji County,Ningxia Autonomous Region from
Apr. 1991 to Jun. 1993. During the field survey, 441 of samples were captured (163 of male and 278 of female)with sex ratio of 0. 59(♂♂:♀♀). Based on the body weight excluding viscera (BWEV) and morphilogical characteristics of skull as well as
reproduction,the age distribution was divided into five groups:Group 1 juvenile with BWEV bellow 100g for mele (mean 80. 49±2.75g),and bellow 80g for female (mean 66. 04±2. 66g).Group 2 subadult with BWEV from 101 to 150g (mean 123. 17 ±2. 56g)for male; 81 ￣ 120g (mean 105. 34±1. 14g) for female.Group 3 adult Ⅰ in which male has the BWEV of 151￣ 220 (average 190. 3 1 2. 309), and female 121～160g (mean 142. 07± 0. 969).Group 4 adult Ⅱ male 221-290(mean 248. 66±2. 459) lfemale 161～200g(mean 176. 04±1.20g).Group 5 senior-male BWEV over 290g (maen 312. 54±5. 18g), female over 200g (213. 00±3.85g). The Gausu Zoker population age has the seasonal change which adult Ⅰ group
dominated in the beginning of reproduction in April,group of 3 and 4 dominated in reproduction period in May and June,however, the group 1 increased signifitly in the end of reproduction in July, the ratio of group 2 raised from Aug. to sept., and group 3 dominated in late Fall (Oct.). The relations between age and body weight,length of body as well as reproduction were also discussed.