Abstract:

Aims: As one of the richest areas of mammal diversity in China, the Hengduan Mountain region is a major source and endemic zone for natural epidemics. However, few studies have investigated the effects of habitat variation and human intervention on the community structure of small mammals via persistent monitoring in this region. Therefore, the aim of this study is to assess the disparities in habitat selection and determine the influence of human disturbance on small mammals’ community structure by monitoring these communities within four characteristic habitats in Diannan Town, Jianchuan County. This will provide information for subsequent local plague control and biodiversity conservation efforts.

Methods: Surveys were conducted in Diannan Town by deploying rat cages randomly in the four predominant habitats (vegetable garden, cropland, shrub and neighborhood region) from January 2005 to December 2017. The time, location, species, and other characteristics of the captured animals were recorded. The Shannon-Wiener diversity index, Pielou evenness index and Simpson dominance index of the four habitats were calculated, and the chi-square test was used to analyze the differences in the number of small mammals captured in four different habitats in Diannan Town.

Results: The species accumulation curves of the four habitats increased at a diminishing rate over time, and the ratio of actual number of species to estimated number of species was greater than 80%, indicating sufficient sampling. This survey captured a total of 16,060 small mammals. The dominant species in Diannan Town are Eothenomys miletus and Apodemus chevrieri, and the number of small mammals captured in each habitat varied highly. The vegetable garden exhibited the highest Shannon-Wiener diversity index (1.26), and the neighborhood region had the lowest (1.08). The vegetable garden and cropland had the highest community similarity index (0.94).

Conclusion: This study finds that species composition, diversity index, and evenness index of small mammals vary among different habitat types in Diannan Town. Regions with high levels of human disturbance and low plant resources have low diversity indices while habitats with good resource conditions and moderate human disturbance have higher diversity indices. Further, habitats with fewer food resources and less human disturbance, such as the shrub habitat, have slightly lower diversity indices. Therefore, rodent borne disease control and prevention, such as that for the plague in Diannan Town, should be focused in cropland and vegetable garden regions.

Key words: small mammals, species diversity, human disturbance, habitat type, community