The world's grassland ecosystems are shaped in part by a key functional group of social, burrowing, herbivorous mammals. Through herbivory and ecosystem engineering they create distinctive and important habitats for many other species, thereby increasing biodiversity and habitat heterogeneity across the landscape. They also help maintain grassland presence and serve as important prey for many predators. However, these burrowing mammals are facing myriad threats, which have caused marked decreases in populations of the best‐studied species, as well as cascading declines in dependent species and in grassland habitat. To prevent or mitigate such losses, we recommend that grasslands be managed to promote the compatibility of burrowing mammals with human activities. Here, we highlight the important and often overlooked ecological roles of these burrowing mammals, the threats they face, and future management efforts needed to enhance their populations and grassland ecosystems.

A mathematical analysis of the changes in plant relative growth rates necessary to increase aboveground production following grazing was conducted. The equation derived gives an isoline where production of a grazed and ungrazed plant will be the same. The equation has four variables (mean shoot relative growth rate, change in relative growth rate after grazing, grazing intensity, and recovery time) and may be analyzed graphically in a number of ways.Under certain conditions, small increases in shoot relative growth rate following grazing will lead to increased aboveground production. Under other conditions, very large increases in relative growth rate after grazing can occur without production being increased over that of ungrazed plants. Plants growing at nearly their maximum potential relative growth rate have little opportunity to respond positively to grazing and potentially can sustain less grazing than plants with growth rates far below maximum. Plants with high relative growth rates at the time of grazing require large increases in growth rate while slow growing plants require only small increases. High grazing intensities are least likely to increase production and high grazing frequencies require greater responses than infrequent grazing events.

Plant responses to herbivory and links to belowground nitrogen cycling were investigated at Wind Cave National Park, South Dakota. Laboratory estimates of net nitrogen mineralization were highest in soils from the more altered areas of prairie dog colonies (Cynomys ludovicianus) and lowest in the adjacent, lightly grazed, uncolonized grassland. The ratio of CO2: net nitrogen mineralized, as index of immobilization, was highest in the uncolonized grassland and lowest in the altered core areas. Soil moisture was an important modifier of in situ field estimates of net nitrogen mineralization. Root biomass, an important carbon source for decomposers in perennial grasslands, was lowest in the altered core area and highest in the adjacent uncolonised grassland. Decreased nitrogen immobilization and increased net nitrogen mineralization in the laboratory incubations likely resulted from decreased root carbon inputs in grazed areas, which limited carbon availability to decomposers. Such increases in plant—available nitrogen may partially explain the frequently reported grazing—induced increases in shoot nitrogen concentrations. These studies suggest that carbon allocation to roots is a key link determining nitrogen—cycling responses to herbivory.

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Global minimum temperatures ( T MIN ) are increasing faster than maximum temperatures, but the ecological consequences of this are largely unexplored. Long-term data sets from the shortgrass steppe were used to identify correlations between T MIN and several vegetation variables. This ecosystem is potentially sensitive to increases in T MIN . Most notably, increased spring T MIN was correlated with decreased net primary production by the dominant C 4 grass ( Bouteloua gracilis ) and with increased abundance and production by exotic and native C 3 forbs. Reductions in B. gracilis may make this system more vulnerable to invasion by exotic species and less tolerant of drought and grazing.