Ice, Snow, and Swamp: Managing Deer in Michigan’s Changing Climate

TitleIce, Snow, and Swamp: Managing Deer in Michigan’s Changing Climate
Publication TypeJournal Article
Year of Publication2015
AuthorsHoving, Christopher L.
JournalMichigan Journal of Sustainability
Date Published04/2015

White-tailed deer (Odocoileus virginianus) in Michigan’s Upper Peninsula exist on the edge of their climate tolerance for cold temperatures and deep snow, especially in the lake effect snow zones of the north half of the peninsula. Each year, deer migrate to conifer swamps to escape the deep snow. Many of these swamps are managed by the Michigan Department of Natural Resources (DNR) as critical deer wintering complexes (DWC), and there has been an effort to acquire and protect additional acres of DWC as deer habitat. Conifer swamps are also managed for many other values, including timber products, which are difficult or impossible to access during mild winters. Recent warming trends have resulted in a 71% decrease in ice cover on Lake Superior, and a concomitant increase in lake effect snow. As the severity of winters in terms of duration of snow depth has increased, DWC habitat has become more critical to deer over-winter survival. However, regional climate models project a shift from lake effect snow to lake effect rain as temperatures continue to rise. Thus, while DWCs have high wildlife habitat value now, their value to deer is expected to decrease by the end of the 21st century. The economic value of timber products is also expected to decrease as access for harvest becomes more challenging. The projected changes in the ecological and economic values of conifer swamps will complicate long-term conservation of these regionally important resources. Conservation tools other than land acquisition could provide managers the flexibility to meet dynamically shifting values across Michigan’s northern forests.