Objective To guide the prediction and control of farmland rodents through revealing the population dynamics of Tscherskia triton. Methods The investigations were carried out from January to December by night trap method during 1994 to 2014 and 500 clamp traps were used in 5 monitoring sites every early month. Some indexes of the captured samples, including body weight, body length, tail length, auricular height and hind-foot length were measured. The samples were dissected to investigate the reproduction situation. The effects of population age structure and reproductive capacity of T. triton, the change of grain acreage and artificial control on population dynamics were analyzed based on the body weight of T. triton. Results Population decreased dramatically when population age structure of T. triton was not complete. The number of adult reproductive females and the population of T. triton were positively related from May to September. Thus, the number of adult reproductive females could be used as the prediction for population dynamics during this period. Population could decrease by changing grain acreage and implementing the rodent pest control continually, which could affect reproductive capacity and population age structure of T. triton. Conclusion Changing grain acreage and artificial control could affect reproductive capacity and population age structure of T. triton. Population of T. triton decreased dramatically and could not recover quickly when population age structure was destroyed and reproductive capacity decreased to a certain level. In addition, the number of adult reproductive females during the main breeding season(from May to September)could be used as the important prediction for population dynamics of T. triton in Shunyi district.

【Abstract】 Objective To indentified the population age of Tscherskia triton scientifically and easily, and to grasp its population age structure so as so increase the prediction level of rodent infestation. Methods The investigations were carried out from early March to early October every year by night trap method during 1994-2006 and 400 clamps were used every time. Some indexes of the captured samples, including body weight, body length, tail length, auricular height and hindfoot length, were measured. The samples were dissected to investigate the reproduction situation. The age of T.triton was identified by mathematical statistics method based on the body weight and its reproductive characteristics. Results A total of 2176 samples captured were divided into five age groups according to the body weight and reproductive characters. They were the young group (Ⅰ, female: less than 35 g. male: less than 33 g), sub?adult group (Ⅱ, female: 35.1-75 g. male: 33.1-79 g), adult groupⅠ(Ⅲ, female: 75.1-121 g. male: 79.1-123 g), adult group Ⅱ(Ⅳ, female: 121.1-185 g. male: 123.1-187 g) and older group (Ⅴ, female: more than 185 g. male: more than 187 g).  Conclusion The  results  showed  that  it  was  very convenient to take body weight as the division standard of T.triton. There was a significant difference among five age groups. The weight increased with the increase of population age. The reproductive capacity was significantly different among different age group, which rose with the increase of age. Sub?adult group and adult groupⅠtook absolute advantage in the population structure.