Badger (Taxidea taxus) Mounds Affect Soil Hydrological Properties in a Degraded Shrub-Steppe

Abstract

Overgrazing, weed invasion and wildfire have resulted in the conversion of large areas of shrub steppe to exotic annual grassland in the western United States. This has been accompanied by reduced habitat for native plants and animals, and altered water and nutrient flows. In these landscapes, badgers increase landscape heterogeneity by creating a mosaic of foraging pits and mounds over extensive areas while preying on fossorial animals. The effects of badger-produced mounds on infiltration and surface physical properties were examined in a mixed sagebrush (Artemisia) – winterfat (Krascheninnikovia) site in west-central Idaho. Recently constructed mounds were physically degraded (i.e., more compacted, poorly aggregated, few macropores, erodible by wind) and vascular plant and cryptogamic crust cover increased as mounds aged. Infiltration through younger mounds was about half that through older mounds or inter-mounds. The results indicate that mounds function as water shedding sites, suggesting that the area around the base of the mounds will be moisture-rich, and may be important for recruitment of shrub-steppe plant species.