Habitat Suitability Modeling for Brown Bear (Ursus arctos syriacus) in Naposhteh-Chai Watershed

Brown bear (Ursus Arctos) is classified as a Least Concern (LC) species of the International Union for Conservation of Nature (IUCN), but its population and distribution have decreased during last decades. This study was carried out to assess the habitat suitability for Brown bear and the effective factors affecting its distribution in Naposhteh-Chai watershed.

Maximum Entropy (MaxEnt) approach available in MaxEnt software was used for the habitat suitability modeling of this species from autumn 2015 to autumn 2016. Information layers determined as affecting variables on this species include the slope, aspect, elevation, land use, water resources, human development variables (villages and roads) and climate.

Results showed that 24.4 percent of Naposhteh-Chai watershed were suitable for Brown bear. Based on habitat suitability map, Brown bear preferred elevation range of 1000 to 2100 meters and slope of 10 to 60 percent. Furthermore, existing of densed forests, farmlands, water sources, villages and also aspect and climate, are important factors in the presence of this species.

Results of model evaluation using the area under the curve (ROC= 0.970) showed that prediction of this model are much more accurate than random conditions. Brown bear suitable integrated habitats, are located in Makidi, Oskolu, Naposhteh and Bala Sang areas. Prevention of tourism development in the suitable habitats of Brown bear, and, determination of corridors and movement routs of the species outside of the Naposhteh-Chai watershed in future studies were suggested in the route of this research.