Courtesy of the Wisconsin Department of Natural Resources

WISCONSIN – DNR Conservation Biologist Jim Woodford recently found an arresting and rare image of two endangered American martens while reviewing trail camera images collected this winter in Chequamegon-Nicolet National Forest.

Woodford and colleagues placed 120 trail camera stations out in the winter since 2018-19. The platforms are rigged with baits to entice the animal to expose its unique fur patterns to the trail camera.

Researchers analyze the images to identify individual animals and develop population estimates, and learn American marten behaviors that help refine the recovery plan for this species.

Three years into the project, the trail cameras are efficiently adding important insights about martens and documenting gains from past marten reintroductions, research and monitoring with partners Chequamegon-Nicolet National Forest, Apostle Islands National Lakeshore, UW-Madison and the Great Lakes Indian Fish and Wildlife Commission.

The trail camera project reveals a stable and sustainable Nicolet population, with a very high annual survival rate of 81%, and notes that martens are shifting their active hours from nighttime to daytime to avoid fishers, a larger competitor and predator.

Trail camera and genetic research in the Apostle Islands show martens thriving and some animals dispersing to boost mainland Wisconsin populations; genetic testing confirms them as recent migrants from Michigan’s Upper Peninsula.