Abstract:The purpose of this study is to accurately grasp the degree of harm and reproductive performance of plateau pikas in the natural pastures of Yushu City, Qinghai Province, understand the dynamic situation of rodent damage, carry out rodent control in time, and improve grassland productivity. This method is to conduct a comprehensive field survey and dynamic monitoring of plateau pikas in Yushu City from 2020 to 2021. The sample area is 1/15 hm2, and they are captured, dissected, observed, measured and counted. The results show that the plateau pika can only reproduce once a year in the severe cold climate of the high altitude of Yushu. 1~9 litter per litter, mostly 3~6 litters, accounting for 91% of pregnant mice, with an average litter of 3.58 litters. The weight of male mice is 158g, and the body length is 147 mm; the weight of female mice is 176g, and the body length is 150 mm. Female mice account for 52.5% of the population. There is a certain correlation between reproductive ability and population sex ratio. We measured the daily food intake of 833 cases by gastrotomy to be 77.3g, which was about 50% of their body weight. An adult mouse can eat 9.5 kg of forage grass for 4 months in the forage growing season, and the amount of forage grass consumed by 52 adult pikas is equivalent to the daily food intake of one Tibetan sheep. However, the feed intake of the plateau pika mixed population was 66.0 g per day, with large food intake, high reproductive rate and strong destructive power.
