Jepson-Innes Karen, Bock Carl E
Department of Environmental, Population, and Organismic Biology, University of Colorado, Box 334, 80309, Boulder, CO, USA.
Oecologia. 1989 Mar;78(3):430-431. doi: 10.1007/BF00379121.
Grasshopper densities were compared between grazed and ungrazed semidesert grassland sites in southeastern Arizona. Bouteloua-dominated perennial grass cover was about 1.5 times greater on the livestock exclosure. Grasshoppers were 3.7 times more abundant on the protected area in the summers of 1983 and 1984, when dominant species were grass-feeding members of the subfamily Gomphocerinae. In fall 1984, grasshoppers were 3.8 times more common on the grazed site, when dominants were mainly herb-feeders in the subfamily Melanoplinae. These results indicate important seasonal and taxonomic differences in the responses of grasshoppers to the activities of vertebrate grazers.
在亚利桑那州东南部，对放牧和未放牧的半荒漠草原地点的蚱蜢密度进行了比较。以布氏草为主的多年生草本植物覆盖度在牲畜围栏内大约是围栏外的1.5倍。在1983年和1984年夏季，当优势物种为瘤角蝗亚科以草为食的成员时，保护区内的蚱蜢数量是围栏外的3.7倍。1984年秋季，当优势物种主要是黑蝗亚科的食草动物时，放牧地点的蚱蜢数量是保护区的3.8倍。这些结果表明，蚱蜢对脊椎动物放牧活动的反应存在重要的季节和分类学差异。
