Landscape-Scale Attributes of Elk Centers of Activity in the Central Black Hills of South Dakota

We researched the environmental attributes (n = 28) associated with elk (n = 50) summer range (1 May–30 Sep) in the central Black Hills of South Dakota, USA, during 1998–2001. We defined high-use areas or centers of activity as landscapes underlying large concentrations of elk locations resulting from the shared fidelity of independently moving animals to specific regions on summer range. We divided the study area into 3-km grid cells to represent the distance elk travel in a 24-hour period. We computed mean elevation and slope, proportion and configuration of overstory canopy cover, proportion and configuration of dominant vegetation type, estimated biomass, road density, traffic rate, and amount of habitat not dissected by improved surface roads for each cell. We used a combination of multiple stepwise regression and likelihood ratio tests to develop spatially adjusted models with total number of elk locations per cell as the dependent variable. Environmental attributes varied in their significance based on their availability to different elk subpopulations. Collectively, the number of elk locations was positively associated (model r2 = 0.50, P < 0.001) with elevation, proportion of non–road-dissected habitat, shape complexity of meadows, proportion of forest stands with ≤40% overstory canopy cover, and proportion of aspen (Populus tremuloides). Elk were responsive to a landscape structure emphasizing forage potential, and their selection was based on the composition and pattern of both biotic and abiotic variables. Defining the characteristics of high-use areas allows management to manipulate landscapes so as to contain more of the habitats preferred by elk.