We examined woodpecker excavation and use of artificial polystyrene snags in four forest types in eastern Texas for five years. Twenty-three of 47 artificial snags were used by Downy Woodpeckers (Picoides pubescens) for cavity excavation and subsequent nocturnal roosting; they did not use the artificial snags for nesting. Although six ather species of woodpeckers were present in the area, only Downy Woodpeckers excavated cavities in the artificial cavity substrate. Entrances to cavities in artificial snags became enlarged within several months of excavation. Other wildlife species using abandoned cavities in artificial snags were Carolina Chickadees (Parus carolinensis), Prothonotary Warblers (Protonoraria citrea), southern flying squirrels (Glaucomys volans), and red wasps (Polistes sp.). In one instance, Carolina Chickadees excavated their own cavity and nested within a polystyrene snag. Until an artificial cavity substrate acceptable for both woodpecker excavation and nesting can be found, the utility of artificial snags as a means to augment woodpecker nesting substrate remains inadequate.
Conner, Richard N.; Saenz, Daniel. 1996. Woodpecker Excavation and Use of Cavities in Polystyrene Snags. Wilson Bull., 108(3), 1996, pp. 449-456