Sheep grazing causes shift in sex ratio and cohort structure of Brandt's vole: Implication of their adaptation to food shortage
Guoliang LI
State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
College of Life Science, University of Chinese Academy of Sciences, Beijing, China
Search for more papers by this authorXianglei HOU
State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
College of Life Science, University of Chinese Academy of Sciences, Beijing, China
Search for more papers by this authorXinrong WAN
State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
Search for more papers by this authorCorresponding Author
Zhibin ZHANG
State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
Correspondence: Zhibin Zhang, State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China. Email: [email protected]Search for more papers by this authorGuoliang LI
State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
College of Life Science, University of Chinese Academy of Sciences, Beijing, China
Search for more papers by this authorXianglei HOU
State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
College of Life Science, University of Chinese Academy of Sciences, Beijing, China
Search for more papers by this authorXinrong WAN
State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
Search for more papers by this authorCorresponding Author
Zhibin ZHANG
State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
Correspondence: Zhibin Zhang, State Key Laboratory of Integrated Pest Management, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China. Email: [email protected]Search for more papers by this authorAbstract
Livestock grazing has been demonstrated to affect the population abundance of small rodents in grasslands, but the causative mechanism of grazing on demographic parameters, particularly the age structure and sex ratio, is rarely investigated. In this study, we examined the effects of sheep grazing on the cohort structure and sex ratio of Brandt's vole (Lasiopodomys brandtii) in Inner Mongolia of China by using large manipulative experimental enclosures during 2010–2013. Our results indicated that sheep grazing significantly decreased the proportion of the spring-born cohort, but increased the proportion of the summer-born cohort. Grazing increased the proportion of males in both spring and summer cohorts. In addition, we found a negative relation between population density and the proportion of the overwinter cohort. Our results suggest that a shift in the cohort structure and the sex ratio may be an important strategy for small rodents to adapt to changes in food resources resulting from livestock grazing.
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Cite this article as:
Li G, Hou X, Wan X, Zhang Z (2016). Sheep grazing causes shift in sex ratio and cohort structure of Brandt's vole: Implication of their adaptation to food shortage. Integrative Zoology 11, 76–84.
