Study On Habitat Selection And Cave Characteristics Of Himalayan Marmot In Zoige

Habitat selection is the process of animals choose a suitable habitat for survive and reproduce,it reflects the response of animals to different environments.It has great significance for wildlife management and prevention to understand its mechanism.Himalayan marmot(Marmota himalayana)is a cavernicolous large rodent,which have a family group.Zoige County is one of the most concentrated distribution areas of China's wetlands,study of habitat selection of marmot can provide a deeper insight into strategies and mechanisms for adapting to the environment of mammals inhabiting the wetland ecosystem.Dens play an important role in the survival of cavernicolous animals.We can explore whether there are differences of physical characteristics between different types of dens and causes,and understand the ecological functions and effects of dens in their survival process through quantitative analysis of their den characteristics.We studied three seasons of habitat selection and den characteristics of Himalayan marmot at Duoma village,Banyou township,Zoige county with random sample method and direct measurement method combined with infrared camera technology from May to October 2017 and April to October 2018.The research of habitat selection showed that:(1)Himalayan marmot will prefer habitats that have larger mounds,smaller mound density and lower soil moisture content;(2)Marmot tend to choose habitats with lower vegetation height and richer vegetation types in spring and summer;(3)Marmot tend to choose habitats with slightly higher vegetation heights and richer vegetation types in autumn.The research of den characteristics showed that:(1)The average outer diameter of the den entrance is 59.3± 21.9(16-100)cm,and its mean width is 45.8± 20.5(18-100)cm;(2)The average inner diameter of the den entrance is 24.4± 4.0(16-39)cm,and the average width is 19.7± 3.5(15-39)cm;(3)The average length is 127.3 ±43.3(60-240)cm from the ground to the deepest point of the first tunnel;the average angle of the tunnel is 45.7±9.5(20-72)°;(4)The average entrance orientation is 195.8± 96.2(3-356)°.There are no significant differences in physical parameters of different dens type except for the inner vertical diameter between sleeping dens and temporary dens that breeding pairs utilized.The habitat selection of the Himalayan marmot is mainly based on safety,rich food supply and good living conditions.This paper explores the habitat selection of cavernicolous animals in the wetland ecosystem and provides a theoretical basis for the adaptation mechanism between animals and environment.Himalayan marmot prefer to utilize the dens that have smaller inner diameter,longer tunnel and moderate angle of den entrance.Such den structure used by the Himalayan marmot is beneficial to help to avoid natural enemies,resist bad weather conditions,facilitate water drainage and maintain the stability of microclimate.This study provides significant basic information for further understand the ecological characteristics of marmot.