Decline of Gray Wolves in Isle Royale National Park

Isle Royale National Park and Gray Wolves

• In 2009, approximately 24 gray wolves lived on Isle Royale, a remote island in Lake Superior.
• By February 2014, the population had dwindled to 9, the second lowest recorded total.
• The primary reason for the decline is likely inbreeding, resulting in skeletal deformities and weakened reproductive capacity.
• Only three pups were born in 2013, highlighting the issue with reproduction.

Genetic Diversity and Ice Bridge

• The ice bridge connecting mainland Ontario, Canada, and Isle Royale no longer forms predictably due to rising temperatures.
• This lack of connectivity is preventing new wolves from crossing and introducing new genes to the population.
• In 2014, an ice bridge formed during an unusually cold winter, allowing one wolf to leave the island and be shot by a hunter on the mainland.

Conservation Dilemma

• Scientists are debating whether to intervene and save Isle Royale's wolves or let nature take its course.
• The U.S. National Park Service has decided not to take immediate action to bring wolves to the island, citing the need for further research and consideration.
• Isle Royale National Park Superintendent Phyllis Green emphasized the need to find a balance between law, science, and long-term stewardship of the island.

Scientific Perspective

• Rolf Peterson, a wildlife ecologist, believes that releasing a few wolves from the mainland onto Isle Royale (genetic rescue) could help revitalize the population.
• Peterson argues that human intervention is necessary, as the natural environment has been disrupted by human activities.
• The research study on Isle Royale has shown that introducing new wolves can lead to a healthier ecosystem, with a rejuvenated population hunting more moose and maintaining a balance in the ecosystem.

Historical Context

• Wolves first arrived on Isle Royale in the 1940s, after crossing the ice bridge from Ontario.
• Moose had made the same trek a few decades earlier.
• The research study on the relationship between predator and prey began in 1959.

Learn about the dwindling population of gray wolves in Isle Royale National Park in Michigan, as documented by scientists from the Wolves & Moose of Isle Royale Project. Explore the challenges faced by the gray wolf population on this remote island in Lake Superior.