Study of relationship between threshold and habitat patches of brown bears (Ursus arctos Linnaeus, 1758) in Sephid-Koh protected area by using land scape approach

Protection of habitat connectivity is a major goal of the protection project, especially for large predators. Habitat patches are desirable zones with different distribution in landscape. These patches with various dimensions and sizes include high-performance segments for presence and establishment. Therefore, investigation of the identification process and changes in the patches for different species of wildlife will provide a correct and accurate picture of their distribution status. This study was conducted to investigate the distribution of habitat patches of brown bear on the landscape scale of Sefidkoh area in Lorestan province. In this regard, habitat suitability was first calculated by maximum entropy method using 10 replicates. After validation of the model using the AUC, different thresholds of logistic output were applied to continuous habitat suitability map. NP, PD, ED, LPI, LSI, SHDI and CONTAG metrics were used to evaluate the continuity. The trend of changes in different metrics showed that by decreasing and increasing the threshold value applied to the continuous map, the suitability of the values related to landscape metrics would be affected. High threshold values represent the key habitat and low threshold values give an optimistic view of the distribution of patches. The results showed that the identification of the appropriate threshold for hot spots analysis is prior to analysis of landscape metrics since this threshold depending on the purpose of the study, the number of presence points, model types, and species conditions will be of different utility.