Investigating Martens at Apostle Islands National Lakeshore

Scientists are studying American martens to learn more about their colonization history on the Apostle Islands.

NPS photo

The American marten (Martes americana) is a mustelid that lives throughout northern North America. Apostle Islands National Lakeshore lies along the southern boundary of its range, and martens inhabit many of the park’s islands. Matt Smith in the Pauli Lab at the University of Wisconsin-Madison is working to determine the colonization history of these martens on the islands. He is also quantifying habitat conditions that influence marten diet and population viability on five of the islands. Martens are a state endangered mammal in Wisconsin, and the research being conducted at Apostle Islands could lead to a better understanding of populations on the mainland as well.

Matthew distributes non-invasive hair traps on the islands to collect hair from the martens. Using DNA extracted from hair samples, they verify the species and obtain multi-locus genotypes to identify unique individuals. The team identified seventeen martens on Stockton Island, 8 on Cat Island, and 7 on Manitou Island. Preliminary results suggest the density of martens on Cat and Manitou Islands are high, and from the literature, these densities represent martens in high quality habitat.