Proximity to Established Populations Explains Moose (Alces alces) Occupancy in Northern Wisconsin

Wildlife conservation and management depends on understanding patterns and changes in the populations and distributions. Moose (Alces alces) sub-populations are alternately declining and increasing in abundance across their circumpolar distribution. Within regional populations a similar variable pattern sometimes exists, such as in the upper Midwest region of the United States where sub-populations are declining in Minnesota but steady or increasing in Michigan. Although abundant before European settlement, little is known about the current state of moose in Wisconsin. We examined citizen science observations of moose collected by the Wisconsin Department of Natural Resources over 25 years to determine the drivers and trends of moose distribution in Wisconsin. Because opportunistically collected citizen-science data may be unreliable for abundance estimates, we used an occupancy framework to understand how variables affect county-level detection and occupancy of moose. We found that detection was driven by area of Intermix Wildland Urban Interface and road density, and occupancy was driven primarily by proximity to Minnesota and Michigan, and appears to have been stable over the previous 25 years. This study offers insight for understanding moose populations on the southern fringe of their circumpolar distribution, and a foundation for understanding the moose population in Wisconsin.