| Home range size estimation,habitat suitability assessment and population viability analysis play important and fundamental roles in the management of wild animals and conservation policy planning.Chinese goral(Naemorhedus griseus)is an unique species in Northeast Asia,due to the aggregation of human activities,habitat fragmentation and habitat loss,Chinese goral is evaluated as a vulnerable species by the IUCN Red List and the China Mammal Red List,and is listed in the Appendix I by CITES.The habitat of Chinese goral in Saihanwula National Nature Reserve,located in the Inner Mongolia of northern China,is surrounded by villages and isolated from other habitats,and faces the risk of population extinction.In this paper,the females' home range sizes and altitude use of habitat of the Chinese goral(n=5)with data from GPS collars were analyzed from February 2015 to September 2018;meanwhile with gorals' spatial distribution data form line transect survey and infrared cameras,we assessed the habitat suitability and the main factors influencing habitat selection of the Chinese goral,Based on monitoring information and references,the updated Vortex package was used to make a simulation analysis on population viability of this closed group.The main results are listed as following.1)The annual home range of the Chinese gorals was 0.205±0.138 km2(Minimum Convex Polygon,MCP95%),0.038±0.022 km2(MCP50%),0.256±0.166 km2(Kernel Density Estimation,KDE95%),0.053±0.034 km2(KDE50%),0.099±0.05 km2(a-Local Convex Hull,a-LoCoH95%),0.022±0.012 km2(a-LoCoH50%).There were significant differences among home range sizes(both at 95%and 50%contours)between individuals(95%contour:MCP:F=341.2,df=3,P<0.001;KDE:F=150.3,P<0.001;a-LoCoH:F=159,P<0.001.50%contour:MCP:F=68.82,df=3,P<0.001;KDE:F=154.1,P<0.001;a-LoCoH:F=122,P<0.001).The seasonal home range was not significant at 95%contour(MCP95%:F=0.072,df=3,P=0.975;KDE95%:F=0.026,P=0.994;a-LoCoH 95%:F=0.101,P=0.959).However,we found significant differences among different methods(MCP,KDE and a-LoCoH)at 95%seasonal home range size(F=32.41,df=2,P<0.001),the home range estimates from the a-LoCoH method were substantially smaller than those of MCP and KDE.The monthly home range was not significant(F=0.451,df=11,P=0.93),but it was smallest in February due to shortage of food resources and low air temperature.The size of female's home range dramatically decreased in May,June and July due to giving birth.2)The results showed home range size derived with terrain information was not significantly larger than that derived without topographic information(Z=-0.843,P=0.399),but the results of home range estimates with terrain information was more effective for animals living in complex terrain.There were spatial overlaps between individuals' home range,and the overlap index was as high as 100%.3)There were significant seasonal differences in habitat altitudes variation of four Chinese gorals(X2=26.776,df=3,P<0.01),with higher altitude habitats used in spring and lower altitude habitats used in winter.And the monthly habitat altitude was lowest in January which may indicate an adaptation to low air temperature.4)In this study,the Generalized Linear Model(GLM),Generalized Add model(GAM)and Classification And Regression Trees(CART)were evaluated by the area under the ROC curve(AUC),Kappa,and true skill statistics(TSS).This process showed that the three models produce accurate predictions.Suitable habitat was mainly distributed in a core zone of Zheng-gou,which was consistent with the results of field observation.The suitable habitat area of 161.15 km2,accounting for 15.12%of the total assessment area by GLM;the predicted area of GAM was 119.77 km2,accounting for 11.23%of the study area;and the predicted area of CART was 134.20 km2,accounting for 12.59%of the study area.The results also showed that the normalized difference vegetation index,the distance to residential sties,terrain ruggedness index and the distance to road were the main factors influencing habitat selection of the Chinese goral.This study suggested that improving the suitable habitat quality and control the entries of people into the reserve to reduce human interference.5)The results indicated that there would be an increase in the population of the Chinese goral in the next 100 years,but the probability of survival would gradually decrease according to the predictions of the Vortex package.In addition,the sex ratio at birth,mortality of infant females and the mortality of adult females will seemingly play crucial roles in determining population persistence according to the sensitivity tests.Based on the study results,provision of feedings and nutrient salt during harsh winter are a decisive way to improve individual survival and breeding conditions in maintaining the present population. |
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