A Study On The Distribution Of Snow Leopard(panthera Uncia)and The Relationships With Its Sympatric Species And Livestock Activities In The Gongga Mountain

Large carnivores play an important role in maintaining the structure and function of ecosystems.However,due to the disturbance of human activities such as retaliatory killing,hunting and land use,population and distribution of large carnivores have shrunk sharply in the past two centuries,and consequently some species even become endangered.Although many measures have been taken for conservation purpose,many large carnivores are threatened by extensive human activities.With the continuous increase of human population and associated demand for meat and animal huabandry,livestock grazing has become one of the most important and urgent issue that challenges the survival and population growth of large carnivores.The distribution shrinking of large carnivors in pastoral areas and their underlying mechanisms need more attention.Snow leopard(Panthera uncia),categorized as vulnerable on the IUCN Red List of Threatened Species and 1st grade National Key Protected Wild Animal in China,is a top predator distributed in the Qinghai-Tibet Plateau and surrounding alpine areas.Due to its mysterious activity traces and low population density,as well as the difficulty in reaching its habitats,the basic investigation and research on snow leopard in many areas are still lacked,such as the Hengduan Mountains in the eastern distribution margin of snow leopard.Systematic investigation and research on the snow leopard in the Hengduan Mountain should be conducted to understand its survival status.Snow leopards mainly live in pastoral areas,while few studies concerning the grazing impacts on their distribution and population growth.The impacts of livestock and grazing activities on the spatial distribution of snow leopard are variable between studies and the underlying mechanisms are still unknown.Based on the results of snow leopard’s distribution survey conducted from 2012 to 2015 in the Gongga Mountain National Nature Reserve,this study investigated snow leopard and its sympatric species in the 675 km2study area from 2016 to 2018 using the infrared camera trap method,aiming to figure out spatial and temporal distribution and habitat status of snow leopard in the Gongga Mountain areas,and relationships of spatial-temporal distribution between snow leopard and its sympatric predators,preys and livestock grazers.This study will fill up the data gap of snow leopard population and distribution in the Gongga Mountain areas,enrich the researches on interspecific relationships in large carnivores and reveal the mechanisms of grazing impacts on the space utilization of snow leopard.The main contents and results of this study were as follows:1.The population and distribution of snow leopard in the Gongga Mountain areasA total of 234 cameras were installed from 2016 to 2018 in the 675 km2research area during the survey,and the total operational time is 23305 days from 216 cameras.At least 5snow leopards were detected in the 375 km2areas.The diel active time of snow leopard was nocturnal(diurnal-nocturnal indexβ<0.54)with activity intensity reaching the peak at 20:00to 01:00.The distribution elevation of snow leopard ranged from 3996 m to 4969 m,and the average distribution altitude was 4674 m.The camera capture rate of snow leopard increased along with the increasing altitudinal gradient.Results of Max Ent model showed that annual precipitation,diurnal temperature range,annual maximum enhanced vegetation index(annual maximum EVI),mean annual temperature,mean annual enhanced vegetation index(mean annual EVI)and land cover were important environmental factors influencing the distribution of snow leopard,and the annual precipitation and diurnal temperature range exerted the greatest impact.The suitable habitat area of snow leopard in the Gongga Mountain areas was predicted to be 4871.25 km2,only occupying 17.73%of the total estimation area(27467.21km2).2.Sympatric mammals of snow leopard in the Gongga Mountain areasThis study identified 26 species of mammals(Ochotona spp.could not identified to species)which belong to 23 genera of 13 family in 5 order.Among all mammals,four species snow leopard,leopard(Panthera pardus),alpine musk deer(Moschus chrysogaster)and forest musk deer(Moschus berezovskii)are under the 1st class national protection in China;and twelve species are under the 2nd class national protection including asiatic black bear(Ursus thibetanus),eurasian lynx(Lynx lynx),stone marten(Martes foina),pallas’s cat(Otocolobus manul),Chinese mountain cat(Felis bieti),yellow-throated marten(Martes flavigula),red panda(Ailurus fulgens),blue sheep(Pseudois nayaur),Chinese serow(Capricornis milneedwardsii),Chinese goral(Naemorhedus griseus),rhesus monkey(Macaca mulatta)and southeast asian sambar(Cervus equinus).There were 15 species classified to Carnivora which had the highest species richness among mammals.There were 11 carnivorous species belonging to predators,and these were snow leopard,leopard,gray wolf,eurasian lynx,red fox(Vulpes vulpes),leopard cat(Prionailurus bengalensis),stone marten,pallas’s cat,Chinese mountain cat,yellow-throated marten,and altai weasel(Mustela altaica).These results indicate the sympatric species of snow leopard in the Gongga Mountain areas are abundant,especially the predatory species.Most sympatric mammals are Chinese endangered animals,which highlight their values for biodiversity conservation and ecological research.3.Relationships of temporal and spatial utilization between snow leopard and its sympatric mammalsLeopard,wolf and red fox were chosen as representative sympatric predators,and blue sheep as major prey species to reveal the relationships of temporal and spatial utilization between snow leopard and its sympatric species in the Gongga Mountain areas.The average distribution elevation of leopard,wolf,red fox were 4509 m,4676 m,4644 m,respectively;and the average distribution elevation of leopard was significantly lower than that of snow leopard(p<0.05).The capture rates of red fox and snow leopard were higher above 4500 m than low altitudes and showed an upward trend with the increasing altitudinal gradient,while leopard had a downward trend.The results indicate that the spatial untilizaion of snow leopard and leopard are divergent.There was not obvious change in the capture rate of wolf between altitudinal zones.Snow leopard,leopard and red fox were nocturnal species(β<0.54),and the nocturnal activities of these three species accounted for 62.92%,63.27%,84.97%of the diel activity time,respectively.Wolf seemed to be a diurnal species(β>0.54),and its diurnal activities accounted for 61%of the diel activity time.There was a significantly negative correlation in the diel activity rhythm between wolf and snow leopard(R~2=0.33,p=0.003).Among the four carnivores,only snow leopard and leopard had highly overlapped diel activity rhythms(△>0.8),while activity rhythms of other species overlapped moderately(0.5<△<0.8).The average distribution elevation of blue sheep was 4616 m,which was non-significantly different from snow leopard(Z=-0.32,p=0.752).The diel activity rhythms of blue sheep and snow leopard overlapped moderately(0.5<△<0.8);however,there was a great difference in the allocation of diel activity time.Contrary to snow leopard,blue sheep appeared to be diurnal(β>0.54)and its diurnal activities accounted for 84%of the diel activity time.4.The relationships of spatial utilization among snow leopard,blue sheep and yakIn order to reveal the relationshiops of spatial utilization between snow leopard and its major preys,the capture rates of blue sheep,himalayan marmot,pika,Tibetan snowcock and snow partridge and environmental factors such as annual precipitation,diurnal temperature range,annual maximum EVI,mean annual EVI were used to fit the capture rate of snow leopard.Only the capture rate of blue sheep had a significantly positive correlation with the square root value of snow leopard’s capture rate(β=0.10,p=0.004,importance value=1),indicating blue sheep is a determinant factor affecting the capture rate of snow leopard.The capture rate of yak and environment factors such as annual precipitation,annual maximum EVI,mean annual EVI,diurnal temperature range were used to fit the blue sheep’s capture rate to figure out the correlation of spatial utilization between yak and blue sheep.Only the yak’s capture rate had a significantly negative correlation with the square root value of blue sheep’s capture rate(β=-0.42,p=0.018,importance value=1).The results of structural analysis model and mediation effect model showed that the indirect impact of yak on the capture rate of snow leopard via blue sheep was significant(interpretation degree=29%,p=0.040),and the direct impact of yak on the capture rate of snow leopard was non-significant(p>0.05).Compared with the areas caputuring snow leopard,the capture rate of yak in the areas without captured snow leopard was higher(Z=-5.34,p=0.000),while the blue sheep’s capture rate was lower(Z=-3.29,p=0.001).Blue sheep mainly utilized areas in high elevations(≥4700 m)where yak was less distributed.In conclusion,there was at least one breeding population including no less than 5 snow leopards within the Gongga Mountain area.Snow leopard here were nocturnal and inhabited at the average elevation of 4669 m,and its space utilization intensity increased as the altitude increases.The suitable habitat of snow leopard was mainly affected by climate and vegetation productivity,and the suitable habitat was predicted to be ca.4871.25 km~2which mainly distributes within the Gongga Mountain Nature Reserve and its surrounding areas.The coexistence mechanisms of different predators with snow leopard are different.The diel activity rhythm of leopard and snow leopard was similar while their distribution elevation was different;while wolf and snow leopard inhabited at similar elevations but had a different diel activity rhythm trend.The activity rhythms of red fox and snow leopard were moderately overlapped and their distribution elevations were accordant.Blue sheep,as the major natural prey of snow leopard,adopted a divergent diel activity rhythm with snow leopard,while their distribution altitudes were similar.In our study,blue sheep is the key limiting factor of snow leopard’s spatial utilization.Grazing influences the spatial utilization of snow leopard and its major prey.Livestocks,i.e.yak,mainly affected the spatial utilization of snow leopard indirectly by their incursions upon the suitable habitats of blue sheep.In consideration of the high biodiversity in the Gongga Mountain areas especially the diverse carnivorous species,there is a great need to reinforce the sustainable management of alpine ecosystem.The monitoring and management of grazing activities also should be emphasized to maintain the biodiversity and functioning of alpine ecosystems.Besides,more researches on the snow leopard and its sympatric species should be conducted in future to understand the roles of top predators in the food web and ecosystem and reveal their values of conservation.