Study On The Activity Pattern And Home-range Of Plateau Zokor During The Warm-season In Eastern Qilian Mountain

The plateau zokor(Myospalax baileyi)is the dominant subterranean rodents on the Qinghai-Tibet Plateau,it plays an important role on the energy flow and material circulation in the alpine grassland ecosystems.Howevr,the zokors also cause grassland productivity decline and soil erosion because of excavating tunnel,foraging plant rhizome and producing mounds.Therefore,the plateau zokor is also regarded as one of the main pest rodents in alpine meadow.It is important to clarify the activity pattern,dynamic changes of home-range and its influencing factors of the plateau zokor under natural situation for studying survival strategies,such as feeding and breeding,as well as scientific control.The paper selected Mayintan of Zhuaxixiulong township in Tianzhu Tibetan Autonomous County in Gansu Province to explore the use of radio-tracking technology in the plateau zokor firstly.The second aim was to study the activity pattern of the plateau zokor and its influencing factors.The third aim was to study the dynamic changes of home-range of the plateau zokor and its individual ability to make mounds.The forth was to study the behavior of the plateau zokor on the ground and its influencing factors.The purpose of this paper was to provide the references for studying the basic ecology of plateau zokor.The results showed:1.The live trap was the precondition of radio tracking for the zokor,the average captured rate of our live trap was 44.12%,the anesthesia time and dosage was closely related with the plateau zokor's bodyweight.When the weight of plateau zokor below 150 g,the dosage of aether was 0.75~1.2 ml/per zokor,the anesthesia time was 30~45 s/per zokor.When the weight was among 150~270 g,the aether was 1.3~1.6 ml/per zokor with anesthesia time was 30~55 s/per zokor.When the bodyweight was among 271~350 g,the aether was 1.6~2.0 ml/per zokor with the anesthesia time was 45~60 s/per zokor.The transmitter should be collared across the neck and under the front leg,and should be recaptured after 30 days to replace the transmitter for long-term studying.2.The plateau zokor displayed pronounced bimodal patterns of activity over the course of 24-hour period.The first peak time of activity intensity was around 6:00 AM from June to September,the second peak time was 20:00~22:00 PM from June to September.During October,the first and sencond peak time was at 8:00 AM in the morning and 18:00 PM in the evening respectively.The discrepancy index of daily activity(?)indicated that the activity time of the plateau zokor was evenly distributed during 24 hours in June.The diurnal and noctumal index(?)indicated that the plateau zokor mainly acted in day from June to October.The peak-type index(?)indicated that the level of bimodal patterns in October during 24 hours was highest,followed by September,July,August and June.The daily-activity time index(AT)indicated that the activity time of the plateau zokor was 7 hours per day in September and was over 10 hours per day in other months.The correlation analysis showed that the activity intensity at 6:00 AM in September was significantly positive correlated with the soil temperature at the depth of 5 cm underground(P<0.05).In other months,there was not significant correlation between activity intensity and soil temperature(P>0.05).3.The home-range of male zokor was larger than the female one in June and October,but it was lower from July to September in 2016.The overlap of home-range was happeded only in June and July in warm-season.In June,the overlap area(FKE: 17.68 m2)and individuals(n=5)were higher than that in July(8.01 m2;n=3).The male individual ability of the plateau zokor to make mounds was higher than female in June,September and October,but less than female in August;The total number of mounds the plateau zokors made were June> September = October> July> August;There was significant correlation between the home-range and the mounds(R=0.455,P<0.01).There was significant correlation between the home-range and the aboveground and underground biomass of grasses(R=-0.247,P<0.05;R=0.364,P<0.01),and it was no significant negative correlation between the aboveground and underground biomass of forbs(R=-0.207,P>0.05;R=-0.09,P>0.05).4.From 2015 to 2016,the activities on the ground of the plateau zokor were mainly appeared at the end of June to early July in 2015,the difference of daily-activity frequency between June and July was not significant(P>0.05),the activities were mainly happened from 6:00 AM to 22:00 PM,Averagely,the zokor spended about 15 minutes on the ground.But,this behavivor was not happened during 2016.Based on the analysis of the changes in foods nutrients and zokor population density over the past two years,the result showed the crude protein and polysaccharide content in underground and overground of plants had no significant difference in June-July and July-August(P>0.05),but the crude protein of underground in plant reached to significant level in June-August during two years(P>0.05).The biomass of underground plants in 2016 was lower than that in 2015 during June to September,but the zokor population density during May to June in 2015 was two times than that in 2016.Based on the above results,it was found that the zokor population density caused the activity on the ground of the plateau zokor.