Home Range Use And Habitat Selection Of Sichuan Snub-nosed Monkeys(Rhinopithecus Roxellana) In Tangjiahe National Nature Reserve

Rhinopithecus roxellana is a rare and endangered species endemic to China.At present,Rhinopithecus roxellana is limited to temperate forests on mountains in Sichuan,Gansu,Shaanxi,and Hubei Province.The Minshan mountains is the main distribution area of Rhinopithecus roxellana.However,the protection and administration of the Rhinopithecus roxellana in this area is severely restricted,due to lack of systematic and in-depth research.Form July,2015 to October,2016,the seasonal home range use and habitats selection of a Rhinopithecus roxellana troop,consisting of 138 individuals were studied at Tangjiahe National Nature Reserve(NNR).The objectives of this study were as follows:(1)Exploring the seasonal home range and habitats selection change rules of Rhinopithecus roxellana;(2)Reavealing the key ecological factors affecting the home range size and habitats selection of Rhinopithecus roxellana;(3)Putting forward some protective measures and administration suggestions specifically.Firstly,the results based on grid-cell method using 200 m grid showed:(1)The annual home range of Rhinopithecus roxellana troop at Tangjiahe NNR is about 18.64 km2,and there were evident seasonal variation in home range size.The home range is minimum in summer(11.56 km2)and maximum in autumn(13.68 km2).In winter,being lack of food and low temperature,the home range size is 13.04 km2,which is smaller than that in autumn.In spring,the home range size is 12.24 km2,ranked third in the four seasons.The primary analysis considered that the difference is caused mainly by the seasonal variation of plants growth,the seasonal distribution and diversity of available food resources of Rhinopithecus roxellana.(2)In different seasons,the intensity of patch use in the home range is uneven,and showed a certain degree of preference to some patches.The differences among habitat patches quality may contribute to it.(3)The population density of the Rhinopithecus roxellana at the Tangjiahe is 7.40 individuals/ km2,which is higher than that in some other areas.It suggests that the habitat quality of Rhinopithecus roxellana at Tangjiahe NNR is relatively good.Secondly,the Vanderloeg-Scavia selective coefficient and the principal component analysis method were carried out to analyze the habitat selection of the Rhinopithecus roxellana at Tangjiahe NNR.The results were as follows:(1)There was an evident seasonal variation about the habitat selection of the Rhinopithecus roxellana,and companioned by a vertical seasonal migration(2)The habitat selection of the Rhinopithecus roxellana at Tangjiahe NNR was jointly affected by several key ecological factors.In spring,elevation,slope position,the distance to water,vegetation type,the average of tree height,shrub height,slope degree and canopy were the key factors,affecting the habitat selection.In summer,elevation,vegetation type,slope position,tree density,canopy,the average of tree height,the average diameter at breast height of tree(DBH)and slope degree were the key factors,affecting the habitat selection.In autumn,the elevation,slope position,tree density,DBH,shrub coverage,the average of tree height and slope aspect were the key factors affecting the habitat selection.In winter,slope position,elevation,the distance to water,habitat type,tree density,canopy,the average of tree height,slope aspect and shrub coverage were the key factors,affecting the habitat selection.Finally,according to the results above,measures and suggestions on administration and protection were provided:(1)Strengthen the protection of original vegetation.(2)Strengthen the protection of the main eatable plant resources.(3)Plant some native and eatable trees of Rhinopithecus roxellana in the areas of lower elevation with sparse vegetation.(4)Strengthen the mornitor of Rhinopithecus roxellana at Tangjiahe NNR.(5)Strengthen the training of staff to improving their professional quality.