Press Release Apr 30, 2019

Annual Study Finds Moose Population Still on the Rise at Isle Royale National Park

Longest predator-prey study demonstrates that wolf introduction is best move for a balanced ecosystem at Isle Royale National Park.

Houghton, MI - Today, lead researchers from Michigan Technological University released their annual winter ecological study, finding that the moose population at Isle Royale National Park has increased to more than 2,000, representing a nearly 20 percent increase over the last eight years. Researchers attribute this growth to the dwindling number of wolves, the island’s only large predator.

This annual ecological winter study, the longest running predator-prey study in the world, has well-documented the decline of the Isle Royale wolves and the rise of the park’s moose population. The National Park Service (NPS) adopted a plan last summer that calls for the introduction of 20-30 wolves over a three-year period in order to address the imbalance between predator and prey. NPS began to implement the plan in the fall of 2018. To date, the park service has successfully introduced two wolves from Minnesota and 11 from Ontario. With the two that already occupied the island, Isle Royale National Park now has 15 wolves.

Statement by Christine Goepfert, Associate Director for National Parks Conservation Association:

“This study confirms that the moose population is continuing to rise and further devastate native plants and trees. The wolves that have been transported to Isle Royale from Minnesota and Ontario will help restore balance between predator and prey and improve the overall ecological health of the park.

“The park service plans to bring more wolves to Isle Royale over the next few years to ensure the island has a thriving and sustainable balance of native plant and wildlife.

“This high-profile partnership between the National Park Service and researchers from Michigan Technological University demonstrates the importance of science-based decision making in managing wildlife and landscapes in our national parks.”


About National Parks Conservation Association: For 100 years, the nonpartisan National Parks Conservation Association has been the leading voice in safeguarding our national parks. NPCA and its more than 1.3 million members and supporters work together to protect and preserve our nation’s most iconic and inspirational places for future generations. For more information, visit

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