Susie Island is the largest of 13 small, rocky islands jutting out of Lake Superior amid the high cliffs and hills of the Pigeon River outlet. In geological terms, the islands are both young and old. The bedrock is slightly metamorphosed sedimentary rock, deposited in a sea over one billion years ago. These rocks were later intruded by molten magma to form resistant dikes. Glaciers of the Great Ice Age scoured the rocks many times over the last two million years, but the Susie Islands only emerged about 5,000 years ago.
In this isolation, a pioneering community of plants continues to thrive. Species that disappeared from the rest of Minnesota after the glaciers receded northward still survive here. Today, many of these plants are more typically found in Arctic and sub-Arctic regions.
Lake Superior, just off Minnesota's north shore near Grand Portage
No Public Access
Because native plant communities that are easily damaged, special permission from The Nature Conservancy is required to land on Susie Island. A good view of the island can be found along Highway 61 between Rose Mountain and the U.S./Canadian customs station.
Why the Conservancy Selected This Site
The archipelago that includes Susie island is identified in The Conservancy’s Great Lakes ecoregional plan and included in the Pigeon River conservation site.
Several factors sustain Susie Island's unique plant community. Located one-half mile from shore, the island experiences more extreme weather than the mainland, resulting in cooler, wetter conditions. Forest fires, a common occurrence on the mainland, have rarely taken hold on Susie Island. In addition, the island's sheer cliffs, rocky promontories and poor soils prove too inhospitable for many plants. This "cloud forest" environment supports a rich variety of mosses and lichens, and a blanket bog of sphagnum mosses one to three feet thick has spread over much of the island.
What the Conservancy Has Done/Is Doing
The Nature Conservancy purchased the South portion of Susie Island in 1971. The remaining section was purchased in the late 1980's. The preserve is named for Francis Lee Jaques, the Minnesota wildlife artist and conservationist. The other 12 islands are owned by the Grand Portage Band of the Ojibway Tribe. The Band and the Conservancy are working cooperatively to protect this archipelago's unique plant life. Collaborative management planning for the Pigeon River Landscape, including the Susie Islands, is underway with several partners including the Ontario Ministry of Natural Resources, the Grand Portage Band of Ojibway, and the National Park Service. Other Conservancy ownership in the area includes the Pigeon River Cliffs Preserve.