Mowing versus fire on expansion of black-tailed prairie dogs reintroduced into Chihuahuan Desert grasslands.

Black-tailed prairie dogs (Cynomys ludovicianus) populations have declined more than 98% due to eradication programs, habitat loss, and introduced pathogens. Active conservation measures for this species, including reintroduction, are under way in a number of areas. Because of their effects on landscape pattern and ecosystem process, they may act as a keystone species in desert grassland communities. As part of a larger study of reciprocal effects of landscape and ecosystem factors on establishment and growth of prairie dog colonies, we investigated the effects of fire and mowing in promoting colony numerical growth and areal expansion. Three prairie-dog colonies were established in the northern Chihuahuan Desert in 1998-1999 ranging in size from 1.27 to 8 ha. Adjacent to each colony we established six 50m x 50m experimental plots randomly assigned to burn or mow treatments. All burrows in each colony were mapped before and after application of treatments. The response variable was number of new burrows appearing in each experimental plot. No significant differences were detected in the number of new burrows in burned vs. mowed plots, suggesting that either fire or mowing can be used interchangeably as management tools in the reintroduction of prairie dogs