The effect of Ecological variables on bird's communities in Hyrcanian forests (Case study: Gorgan Township)

The ecology characteristics of species and habitat variables is one of the main pillars of species protection and forest.Tropical forests are deterioration rapidaly through deforestion and habitat fragmentation, which are major causes of biodiversity loss. Birds and environmental variables, including litter depth, the number of trees with dbh (0-20, 20-50, 50-100 and 100-300 cm), canopy cover trees, humidity, the number of snags, the number of logs litter cover, rocks cover, temperature, vegetation cover were studied using distance sampling method within 25 and 5 m radius of each of 74 sampling points during two seasons (autum and spring) in Hyrcanian forests.The Interactive variables significant was calculated by Minitab 15.0 software.The Results showed that habitat variables include, the number of trees with dbh (20-50, 50-100 and 100-300 cm), canopy cover trees were the most important variables affecting the presence of birds especially, Red-breasted Flycatcher, Great Tit, Blue Tit and Nuthatch in the study area. The results of this study indicated the importance of forest and patches for conserving and enhancing of avian.