The Denning Habitat Of Asiatic Black Bear(Ursus Thibetanus) During Winter In The Wangqing Region,Jilin Prov.China

In the northeast of China,the snow-covered period lasts up to six months.The environment is harsh and food is lacking.The hibernation of Asiatic black bears(Ursus thibetanus)is a breeding season.A series of physiological activities in the hibernation period are carried out in bear den.Whether the black bear can find a suitable bear den and enter the hibernation period is a prerequisite for its safe hibernation and reproduction.Therefore,the study attempts to explore the habitat selection of winter bears in the northeast region and the suitable habitat evaluation and prediction of bears.Through the study,it provides a scientific basis for the protection and restoration of the bear den of habitat in winter in the northeast area and environmental friendly forest management.The study conducted denning survey of Asiatic black bears in the Wangqing area of Jilin Province during the three successive winters from November of 2015 to April of 2017.We set a total of 54 transect lines that length of the all transect lines were 432km,and the total survey area was 17,280hm2 In the transect line survey,a total of 24 bear dens were found,10 of which were old ones(4 had collapsed and 6 were abandoned for many years),and the remaining bear den were selected for the current year.The results of the denning habitat study showed that 1)24 bear den are all tree den,bear used only one species of tree that is Populus cathayana.The average diameter at breast height(dbh)was 126.64±25.37cm.2)Aspects of den entrance is within the range of the solar azimuth,which can also indicate that the aspects of den entrance is related to sunlight.The minimum angular separation between the aspects of den entrance and the wind direction is a right angle,indicating that the aspects of den entrance selects the leeward.And the aspects of den entrance face the slope,forming a certain angle with the gully,indicating that the leeward is selected for denning.The choice of the aspects of den entrance is related to the sunlight and wind direction.3)The width of the entrance is 39.87±5.083.The distance from the entrance to the ground is 13.29±3.049m.4)The bedding of nest is the rot inside of denning timber.The bedding of nest of black bear require only a single material.It shows that the black bear denning option has little relevance to the bedding.The evaluation results of the denning habitat with MAXENT show that 1)Habitat suitability decreasing with increasing distance to Sparse(<15%)vegetation,Open(15-40%)needle-leaved deciduous or evergreen forest(>5m),Mosaic grassland(50-70%)forest or shrub-land(20-50%),Closed(>40%)broadleaved deciduous forest(>5m),Mosaic forest or shrub-land(50-70%)grassland(20-50%),river.2)Habitat suitability decreasing with rising to elevation.Habitat suitability decreasing with increasing slope.Habitat suitability increasing with increasing distance to road.3)There is no difference in the aspect of the bear den.4)The suitability area of bear den of Wangqing National Nature Reserve is 7740 hm2,accounting for 11.5%of the entire study area.