红耳巢鼠种群特征初步研究

Preliminary study on the population characteristics of Micromys erythrotis

红耳巢鼠是啮齿类中体型最小的鼠类之一,我国对其种群特征研究很少。收集贵州省余庆县、凯里市夹捕和围栏陷阱捕获的91只红耳巢鼠样本,统计分析其相关种群特征。结果显示,红耳巢鼠平均体重为8.22 g,平均胴体重为6.00 g,平均体长为66.45 mm,平均尾长为73.97 mm,平均后足长为14.39 mm,平均耳长为10.58 mm,雌、雄鼠上述形态特征指标差异不显著。平均肥满度为(2.89±0.84)g/cm^(3),两性之间肥满度差异不显著;春季和秋季肥满度明显高于夏季和冬季,夏季与秋季间有显著差异;肥满度随着年龄的增长而增加,老年组与幼年组和亚成年组有显著差异。种群数量雌雄性比为0.69,雌鼠总体怀孕率为32.43%,平均胎仔数为4.33只,雄鼠睾丸下降率为44.44%,繁殖指数为0.57,春季、夏季是该鼠的繁殖高峰期。种群年龄组成看,亚成年组、成年组个体数量在种群中占绝对优势,合计种群占比为81.32%;不同季节种群年龄组成明显不同。

Micromys erythrotis is one of the sm allest rodent species,and there are few studies on its population characteristics in China.We collected 91 individuals of M.erythrotis in Yuqing and Kaili of Guizhou province over the years and analyzed their population characteristics.The results showed that the average body weight was 8.22 g,the average carcass weight was 6.00 g,the average body length was 66.45 mm,the average tail length was 73.97 mm,the average hind foot length was 14.39 mm,and the average ear length was 10.58 mm.There was no significant diference in the above morphological characteristics between males and females.The average fatness was(2.89±0.84)g/cm^(3),and there was no significant difference between the two sexes.The fatness in spring and autumn was significantly higher than that in summer and winter,and there were significant differences between summer and autumn.Fatness increased with age,and there was a significant difference between the elderly group,the juvenile group,and the sub-adult group.The ratio of female to male was 0.69,the mean pregnancy rate of females was 32.43%,the average litter size was 4.33,the male testicle decline rate was 44.44%,and the reproductive index was 0.57.The species had a breeding peak in spring and summer.The age composition of the population in the whole year presented a typical pyramid-shaped normal distribution,among which the number of individuals in the sub-adult group and the adult group was absolutely dominant in the population,accounting for 81.32% of the total population.The age composition of the population was different in different seasons.