Reuse of Woodpecker Cavities in The Breeding and Non-Breeding Seasons in Old Burn Habitats in The Black Hills, South Dakota

Recently, greater attention has been given to the potential keystone interaction between cavity excavators and the community of animals that use cavities. However, most research has focused on avian use of cavities in the breeding season, with little attention given to other cavity using guilds or cavity use during the non-breeding season. Furthermore, most breeding season studies were in unburned forests containing a mix of conifer and deciduous trees with much less attention given to cavity rich post-burn habitats. The objective of this study was to examine cavity use during the breeding and non-breeding seasons in old-burned ponderosa pine forests in the Black Hills, South Dakota. One hundred seventy nine active cavity nests of nine cavity nesting species were monitored between 2002–2005. We examined the contents of each cavity during the breeding season and twice during each non-breeding season (fall, winter, spring) each year. Additionally, we conducted vegetative surveys to determine the microhabitat variables that might influence the occupancy of cavities in the breeding season. Binomial logistic regression with AIC model selection criteria were used to model breeding season cavity reuse for the three most common cavity excavator species, Lewis's Woodpeckers (Melanerpes lewis), Red-headed Woodpeckers (M. erythrocephalus) and Northern Flickers (Colaptes auratus). All three species reused old cavities most recently used by conspecifics for breeding; snag density (dbh > 23 cm) and cavity height consistently influenced reuse of cavities for all three species. In the non-breeding season the cavities of these same three species were all commonly used, but Northern Flicker cavities contained the greatest diversity of secondary cavity users. We speculate that Northern Flicker cavities may have been used more frequently in the non-breeding season because of their lower cavity height compared to other similar sized cavities.