Modeling habitat potential for elk expansion in Michigan, USA

ABSTRACT Elk (Cervus elaphus) range expansion and reintroduction is a topic of national interest in wildlife management. Eastern states are facilitating the recolonization of elk to historic ranges. Success of these herds depends on habitat evaluations, site-specific considerations of human tolerance to elk and interactions between elk and existing wildlife. Interest in elk restoration has increased for multiple stakeholders in Michigan (USA), where prospering elk suggest there is potential for range expansion. Habitat quality at the landscape scale for elk in Michigan depends primarily on available forage, suitable cover, habitat diversity, and road densities so we quantified these factors in the Upper Peninsula and northern Lower Peninsula of Michigan using a habitat suitability index model framework. We focused our analysis on target areas of interest and compared habitat suitability values occurring at those locations to values occurring within the current elk range (Pigeon River County State Forest area, or Pigeon River). We used elk habitat utilization information associated with the Pigeon River to validate and adjust our habitat suitability model. We also included a model that assigned less weight to the road density parameter, to account for uncertainty regarding the influence of roads on elk. Results from our habitat models suggested that patches of moderately suitable habitat exist outside the Pigeon River range in Michigan. Target areas differed in quality and quantity of habitat when compared to existing elk range, but habitat suitability values overlapped considerably among locations. Large patches of moderately suitable habitat also occurred outside of target areas. Results suggest that Michigan has potential to support an expanded elk range; however, additional site-specific considerations (land ownership, winter snowpack, deer-elk interaction, wolf density) likely need to be accounted for at potential restoration and expansion sites.