eurasian nuthacth (sitta europaea) habitat suitability modelling at northern alborz, iran

the aim of this study was to develop a methodology to identify suitable habitat of the eurasian nuthatch (sitta europea) at kheyrood forest, northern alborz, iran. this study was carried out during spring to summer 2008. with attention to the area and topographic condition of kheyrood forest, patom, namkhane, gorazbon, cheler and baharbon were selected as data collecting series. the present study focused on vegetation structure and floristics, as well as topographic factors (slope, elevation, and direction). in sampling stager at observation point in the line transect path, habitat parameters and presence and absence of nuthatches were recorded. in each plot all individuals that were observed or being heard, were designated as presence point and other cases were named as an absence point. based upon this monitoring, 78 plots were collected as the presence and 20 plots were counted as absence point during spring season. binary logistic regression was performed to develop the distribution model of the eurasian nuthatch according to habitat variables. finally as a result, the significant parameters in this model were height, diameter, stand and type of trees. according to the results, suitable habitat for s. europaea was considered as all the forest areas where old-growth trees with large bounds are abundant. in fact habitat quality is related to the abundance of old trees. also, the presence of carpinus betulus and fagus orientalis was identified as an important factor for habitat selection.