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犬尾田鼠在斑块生境中更喜好内部区域

WOLFF Jerry O,BOND Monica L   

  1. Department of Biological Sciences,St. Cloud State University,St. Cloud,MN. 56301,USA
  • 出版日期:2008-03-13 发布日期:2008-07-07

Gray-tailed voles prefer interior to edge habitats

WOLFF Jerry O, BOND Monica L   

  • Online:2008-03-13 Published:2008-07-07

摘要: 我们在斑块化的景观中实验测定了犬尾田鼠(Microtus canicaudus)的生境喜好,验证下列假说:在一斑
块生境中,与边缘区域相比,雌性田鼠喜好内部区域。在低密度和高密度时成年雌性的巢区在生境内部区域分别占100% 和76% 。高密度时在边缘区域雌性的捕获率较低,这种差异在低密度时更突出。在高密度时通过选择性去除生境内部和边缘区域的一些雌体,边缘区域13 只雌体中8 只(占62% )的巢区发生从边缘到内部区域的转移,内部区域20 只雌体中只有3 只(占15% )的巢区向边缘区域转移。动物的繁殖率、生存和体重在两个区域之间没有差异。但是,边缘区域个体的巢区比内部区域的要小。这些结果支持一些关于其他啮齿动物的研究观察结果(如鼠平类和田鼠类),但与草原田鼠不同。因此在一斑块生境中,与边缘区域相比,长尾田鼠更喜好内部区域,边缘区域与内部区域的比率可潜在影响动物的生境选择,也可能会影响斑块化生境中的种群统计学特征。

关键词: 边缘效应, 犬尾田鼠, 生境斑块, 巢区, 景观生态学

Abstract: We examined habitat preference of the gray-tailed vole (Microtus canicaudus), in an experimental fragmented landscape to test the hypothesis that female voles prefer interior to edge habitats. One hundred percent and 76% of adult female home ranges were located in interior habitat at low and high densities,respectively. The proportion of captures of females in edge habitat was lower at both low and high densities,but this difference was most pronounced at low densities. After selective removal of some females from interior and edge habitats at high densities, 8 (62% ) of 13 females shifted their home ranges from edge to interior habitats compared to only 3 (15% ) of 20 females moving from interior to edge habitats. Reproductive rates,survival,and body mass were comparable for females in edge and interior habitats. However, home range sizes were smaller for females in edge than interior habitats. These results support descriptive studies on some other small rodents e.g, Clethrionomys sp. and some Microtus sp., but differ from those of meadow voles, M. pennsylvanicus. We conclude that gray-tailed voles prefer interior to edge habitats and that the ratio of edge to interior habitats can potentially affect habitat selection and perhaps overall demography in fragmented landscapes.

Key words: Edge effects, Gray-tailed voles (Microtus canicaudus), Habitat patches, Home range, Landscape ecology