Effects of vegetation, elevation and human disturbance on the distribution of large- and medium-sized wildlife: a case study in Jiuzhaigou Nature Reserve

Animals are integral components of ecosystems, and play important roles in maintaining their function. However, animals are affected by various factors in their habitats. For example, vegetation is an important component of habitat, providing refuge and food. A single mountain may provide a series of climatically different ecological zones over a short elevation change and thus provide diverse habitats for wildlife. Both vegetation and elevation affect wildlife distribution. Protected areas are attracting an increasing number of people and are vulnerable to urban development, which inevitably influences the activity and survival of wildlife. Jiuzhaigou National Nature reserve, which is located in the north of Sichuan Province, in southwest China, has a population of more than 1000 indigenous people, along with a high diversity of wildlife, and in recent years has received nearly 2 million visitors each year. To identify the effects of the environment and human activities on wildlife, and to develop biodiversity protection measures, long-term population monitoring is necessary. Data were analyzed from 8 wildlife monitoring transects in Jiuzhaigou Nature Reserve from 2003 to 2010 to investigate the effects of vegetation, elevation and human disturbance on the distribution of large- and medium-sized wildlife. Twenty-six species of large- and medium-sized wildlife were observed, consisting of 18 species of animals and 8 species of birds, 5 and 11 species of which belonged to the first and second class of protected animals in China. Large- and medium-sized wildlife were most abundant in mixed and coniferous forest (26 and 17 species); less in deciduous broadleaved forest and shrub (10 and 12 species); and least in grassland (2 species). Only 10 species were found below 2400 m; the number increased to 20 between 2400 and 2599 m; after which the number declined with increasing elevation. Human disturbance has had significant effects on large- and medium- sized wildlife distribution. Because of human activities, the original primary forests changed into secondary deciduous broadleaved forest, shrub and grassland, which led to a lower abundance of large- and medium- sized wildlife on the lower slopes (elevation of 0 - 199 m relative to the starting point of the monitoring transect) in Shuzheng, Yanan and Jianpan (4, 2 and 2 species respectively). Human disturbances, including tourism and traffic, probably led to loss of protected animals in the adjacent 50 m elevat