Flora and Fauna Associated with Prairie Dog Colonies and Adjacent Ungrazed Mixed-grass Prairie in Western South Dakota

Abstract

Vegetation, small rodents, and birds were sampled during the growing seasons of 2 years on prairie dog (Cynomys ludovicianus) colonies and adjacent mixed-grass prairie in western South Dakota. Prairie dog grazing decreased mulch cover, maximum height of vegetation, plant species richness, and tended to decrease live plant canopy cover compared to that on ungrazed mixed-grass prairie. Buffalograss (Buchloe dactyloides) was the dominant plant on prairie dog towns and western wheatgrass (Agropyron smithii) and blue grama (Bouteloua gracilis) were most common on mixed-grass prairie sites. Prairie dog towns supported greater densities of small rodents but significantly fewer species compared to undisturbed mixed-grass sites. Deer mice (Peromyscus maniculatus) and northern grasshopper mice (Onychomys leucogaster) were more abundant on prairie dog towns than on undisturbed mixed-grass sites. Density and species richness of birds were significantly greater on prairie dog towns. Horned larks (Eremophila alpestris) were most common on prairie dog towns, whereas western meadowlarks (Sturnella neglecta) were most common on mixed-grass prairie.