Comparison of nest holes between Syrian Woodpecker (Dendrocopos syriacus) and Middle Spotted Woodpecker (Dendrocoptes medius) around Yasouj city in Southwestern of Iran.

In this study, the nest-cavity characteristics of Middle Spotted and Syrian Woodpeckers as well as tree characteristics (i.e. tree diameter at breast height and hole measurements) chosen by each species were analyzed. Our results show that vertical entrance diameter, chamber vertical depth, chamber horizontal depth, area of entrance and cavity volume were significantly different between Syrian Woodpecker and Middle Spotted Woodpecker (P < 0.05). The average tree diameter at breast height and nest height between the two species were not significantly different (P > 0.05). For both species, the tree diameter at breast height and nest height were not significantly correlated. The directions of nests entrances were different in two species, not showing a preferentially selected direction. These two species chose different habitats with different tree coverings, which can reduce the competition between the two species over selecting a tree for hole excavation.