Working to keep the West special

Great Lakes National Parks in Peril

Human-caused climate disruption is already damaging national parks in the Great Lakes region, according to a 2011 report by the Rocky Mountain Climate Organization (RMCO) and Natural Resources Defense Council (NRDC).

The report focuses on the five largest Parks on the Great Lakes, which attract a combined four million visitors annually: Indiana Dunes National Lakeshore (NL) in Indiana; Sleeping Bear Dunes NL, Pictured Rocks NL, and Isle Royale National Park (NP) in Michigan; and Apostle Islands NL in Wisconsin.

The report documents the following major impacts:

  • Higher temperatures. Summers in Indiana Dunes could become as hot by late in this century (2070- 2099) as summers in Gainesville, Florida, have been in recent history (1971-2000). Summers in Sleeping Bear Dunes could become as hot as those in Lexington, Kentucky, recently have been.

  • Less winter ice. Higher air and water temperatures already are reducing winter ice cover on the Great Lakes, a trend expected to accelerate. Lake Michigan may have some winters with no ice cover in as soon as 10 years, and Lake Superior may typically be ice-free in about three decades.

  • Erosion of shorelines and dunes. With less ice and more open waters, the lakes will have more waves in winter than before, especially during strong storms, increasing erosion threats to park shorelines, dunes, and strructures. The park staff at Sleeping Bear Dunes has expressed concern that the park’s signature perched dunes, atop towering bluffs above the shorelines, could be vulnerable to accelerated loss from increased erosion, resulting from a loss of winter ice and snow cover that keeps the dunes’s sand from blowing away and from more waves undercutting the bluffs on which the dunes perch.

  • Loss of wildlife. In Isle Royale, the moose population has declined to half the long-term average. Temperatures higher than moose can tolerate are suspected to be responsible—as in nearby northwest Minnesota, where the moose population has crashed in the past two decades from 4,000 to fewer than 100 animals, coinciding with higher temperatures. Also, warmer winters in Isle Royale enable many more ticks to overwinter so that a single moose can be infested by 80,000 ticks, causing such a large loss of blood that the moose are more vulnerable to the park’s wolves, which also have declined in number. Other park mammals at risk as the climate changes include lynx and martens.

  • Loss of birds. Birds at risk of being eliminated from the parks include common loons and ruffed grouse, iconic birds of the Great Lakes and the North Woods. Already, botulism outbreaks linked to high water temperatures and low lake levels now kill hundreds to thousands of birds a year in Sleeping Bear Dunes NL. So many dead birds cover the park’s beaches that the National Park Service patrols from June through November to clean up the bird carcasses.

As Stephen Saunders, president of RMCO and the report's primary author, said, "Already, threads are being pulled from the tapestries of these parks, and the tapestries are beginning to lose their luster. How much damage is done to these national parks depends on whether we continue pumping heat-trapping pollution into the atmosphere or get smart and serious about cutting those emissions."

Larry MacDonald, mayor of Bayfield, Wisconsin, just outside of Apostle Islands, said, "The City of Bayfield, as the gateway community to the Apostle Islands National Lakeshore, faces the financial reality that climate change will bring tremendous economic challenges to our national lakeshore-based local tourism economy."

Downloads and links:

  • The full report is here (4 MB in size).
  • A higher-resolution, larger (9 MB in size) version is here.
  • A news release on the report is here.

Pictured Rocks National Lakeshore photograph © North Photography