Birds associated with black-tailed prairie dog colonies in southern shortgrass prairie

We conducted a census of avifaunal richness and abundance on black-tailed prairie dog (Cynomys ludovicianus) colonies and uncolonized shortgrass prairie in the Oklahoma panhandle in July 1995 and April-June 1996. Five black-tailed prairie dog colonies were paired with five uncolonized prairie sites having similar topography and soil structure. Data were collected by walking permanent line transects and making point counts with a 125-m radius at fixed points placed 250 m apart. Avifaunal abundance and species richness were determined for each site. Avifaunal abundance was significantly higher on sites with prairie dog-colonies than at uncolonized sites during the vegetation growing season. However, we found few significant differences in avian abundance between prairie dog colonies and uncolonized prairie during tile drought months of 1996. We suggest these differences are because of drought-induced vegetation dormancy. Drought created homogeneous habitat instead of distinct habitat patches on prairie dog colonies characteristic of normal precipitation years in other regions of the Great Plains.