瑞士西部农田周围生态保留带中小型兽类种群结构特征及数量动态的初步研究

为了评价生态保留带对小型兽类种群的影响，2003年7月至2004年6月在瑞士西部Salavaux，chevmux和Montbrelloz 3个地区采用标志重捕方法对小型兽类种群进行了研究。在3个生态保留带中，共发现6种1206只小型兽类，其中普通田鼠、小林姬鼠、中麝晌捕获数量多。普通田鼠为优势种。普通田鼠的种群数量在生态保留带间有差异，但具有相同的季节性波动趋势，一般种群数量随着植被覆盖度和食物丰富度的增加，春季末开始出现增加，仲夏达到最高水平。种群中雌雄个体年龄结构之间有明显的差异，成体和亚成体的数量比幼体多，雄性亚成体的数量比雌性多，雌性成体数量比雄性多（X^2=44．09，df=10，P〈0．001，N=203）。普通田鼠种群中雌雄个体体重之间有明显的差异，雄性的体重比雌性大（t一检验：t=5．011，df=162，P〈0．05，N=213）。种群性比之间有明显的月间变化，雌性的捕获次数比雄性大。普通田鼠只在短距离范围内活动，在生态保留带中的巢区为350～400m^2，雌雄个体的巢区大小之间没有显著性差异。

The Population Structure and Dynamics of Small Mammals in Set Aside Areas in Western Switzerland

In this paper in order to assess the effect of set aside to small mammal populations, one year field study using mark and recapture method was performed in set aside fields in Salavaux, Chevroux and Montbrelloz in western Switzerland. There are 3 species were regularly caught in the set asides: the common vole(Microtus arvalis), the white toothed shrew(Crocidura russula), and the wood mouse(Apodemus sylvaticus). The common vole was the most numerous species in the three set aside fields. Population size of common voles was different between the set aside, but fluctuations in animal numbers were similar, showing a rapid increase as cover and food abundance increased in the set asides during late spring, leading to peak in midsummer. The age structure differed between males and females, most individuals captured during this study are adults and subadults. There were more subadult males than female and more adult females than males (x 2 =44.09, df=10,P<0.001,N=203). There was a significant difference in body mass between the sexes among common voles, males were significantly heavier than females(t-test unequal variances: t=5.011, df= 162, P<0.05,N=213). The sex ratio was very different for the different months, females being more frequently captured than males and there was no similarity between the set asides. The home range size of common voles lied between 350 and 400 m 2 ; the individuals move only short distances and there were no significant differences between males and females.