Butterfly species have proven to be useful indicators of environmental change in many ecosystems. Their tight association with plant communities and their sensitivity to microclimates can provide insight regarding changes in landscape or vegetative composition. Here we report on a study within two regions of the Greater Yellowstone Ecosystem where butterflies have been surveyed in montane meadows along a hydrological gradient since 1997. We have studied this system to better understand butterfly community ecology within one of the most pristine meadow systems in the lower 48 of the United States. This research examined the temporal and spatial patterns of montane meadow butterfly communities in relation to meadow moisture availability and quantity of floral and larval host plant resources. This information is a valuable tool for conservation of montane meadows, and could be useful in monitoring meadow changes due to climatic, anthropogenic, or other natural changes in the landscape.