摘要
2004年9月25日至10月15日,在内蒙古锡林郭勒盟阿巴嘎旗白音图嘎苏木研究了布氏田鼠(Lasiopodomys brandtii)秋季家群数量与来自艾虎(Mustela eversmanni)的捕食风险。布氏田鼠家群数量调查采用标志重捕法和最小已知存活数估计法(即MNA法)确定,而艾虎对布氏田鼠捕食风险的衡量指标采用在研究期间布氏田鼠洞群区新出现的艾虎粪便和挖掘痕迹。研究区面积4 hm2,涉及91个布氏田鼠家群,658只布氏田鼠,其中,17个布氏田鼠家群有新出现的艾虎粪便,5个家群被艾虎掘开。运用非参数的Mann-Whitney U检验进行数据分析,从艾虎遗留的粪便痕迹来看,未出现艾虎粪便的布氏田鼠家群总秩和为1 096,出现艾虎粪便的田鼠洞群秩和为3 090,统计量U=315,校正Z=﹣3.241,校正P=0.001 2;另外,从艾虎掘开的田鼠家群来分析,没有被艾虎挖掘的布氏田鼠家群秩和为3 757,而被艾虎掘开的田鼠家群秩和为429,统计量U=16,校正Z值为﹣3.514,P=0.000 4。两组差异达到极显著水平,表明艾虎对秋季高数量的布氏田鼠家群具有显著的优先访问和攻击偏好,也意味着高数量的布氏田鼠秋季家群具有更高的被艾虎捕食的风险。
In this project wen studied the influence of social group sizes on the predation risk of Brandt′s voles（Lasiopodomys brandtii） in the Xilinguole typical steppe,Inner Mongolia,Abagaqi Centre from September 25 to October 15,2004.We also tested the effects of the predation from steppe polecat（Mustela eversmanni） on the group size of the Brandt′s vole in the same study area.We used the capture-recapture methods to estimate the group sizes of Brandt′s voles（MNA）.Meanwhile,we recorded both the feces and holes excavated by steppe polecats within the habitat of each Brandt′s vole colony as the indicators of its predation pressure.We used the U statistic of nonparametric Mann-Whitney test to detect differences in social group sizes between the colonies with and without the signs of the polecat activities.Totally,91 colonies of Brandt′s voles and 658 Brandt′s voles were observed in the study site with 4 hm2 in size.Of them,we found 17 fresh steppe polecat feces in Brandt＇s vole colonies and.five excavated vole colonies（Table 1）.The results show that the rank sum of the colonies without feces of the polecat was 1 096,while those with the polecat feces was 3 090（U = 315,Adjusted Z Value =﹣3.241,Adjusted P = 0.001 2）; the rank sum of the colonies holes destroyed by the polecat was 429,whereas,the rank sum of the colonies were not dug by the polecat was 3 757（U = 16,Adjusted Z Value =﹣3.514,Adjusted P = 0.000 4）.The results of Mann-Whitney test suggest a significant difference in predator preference between the two groups of colonies（Table 2）.This difference indicates that the steppe polecat significantly prefers to hunt in the Brandt＇s vole colonies with high group sizes.They spend longer time in the colonies with more burrow entrances.This finding indicates that the colonies with larger social group sizes result in a higher predator risk.
出处
《动物学杂志》
CAS
CSCD
北大核心
2016年第2期176-182,共7页
Chinese Journal of Zoology
基金
公益性行业(农业)科研专项经费项目(No.201203041)
关键词
布氏田鼠
越冬家群数量
捕食风险
艾虎
Lasiopodomys brandtii
Over-winter group size
Predator risk
Mustela eversmanni
