Lake Michigan

10,000 BCE - present

Lake Michigan is situated just south of Lake Superior and connects to Lake Huron via the Straits of Mackinac. Lake Michigan was historically oxygen rich and low in algae production, making it exceptionally habitable for many fish species. Over time, however, these populations have suffered from overharvesting and aggressive invasives such as the Sea Lamprey and Zebra mussels. The waters have completely changed; algal production spikes yearly, and many species of fish must be manually stocked for sport fishing. Once home to a diverse assortment of native flora and fauna, its shores now serve as ports for surrounding cities including Chicago, Milwaukee, and Green Bay. Industrial and residential development have degraded Lake Michigan’s shoreline health, as well as its deep-water species. Sand dune erosion and deforestation are among the most dangerous threats to Lake Michigan’s ecosystem.

BIRDS: 2 species are extinct and 5 are endangered
FISH: 5 species are extinct and 4 are endangered
MAMMALS: 2 mammal species are extinct and 4 are endangered
BIVALVES: 2 mussel species are extinct
PLANTS: 2 species are extinct

The territory of the Hudson River watershed falls within the ancestral homelands of the Anishinabewaki, Bodéwadmiakiwen, Kaskaskia, Kiikaapoi, Menominee, Myaamia, Očhéthi Šakówiŋ, Odawa, and Peoria peoples.

Territorial recognition: https://native-land.ca/

Most Pressing Issues

Invasive Species

Invasives such as the Asian carp, sea lamprey, alewife, zebra mussel, and the round goby are just a few of the species that have wreaked havoc on the Great Lakes. These invasive species decimate native populations both by lacking predators and creating low oxygen environments which trigger the production of bacteria that cause botulism. In the 1960s, Alewives made up 90% of the fish in the Great Lakes, posing a major threat to native populations.

Sand Dune Erosion

Storms around the Great Lakes are intensifying as a result of global warming. A higher frequency of flash floods is causing major erosion of the sand dunes around Lake Michigan. Sleeping Bear Dunes and Indiana Dunes National Lakeshores are home to exceptionally diverse flora and fauna and conservation is crucial to prevent extinction. The erosion has led to habitat loss of the piping plover, and the species is now considered endangered.

Development

During the nineteenth century, much of the land surrounding the Great Lakes was cleared and cultivated for industrial and residential development. Building, mines, power plants, coastal roads & recreational infrastructure has been disrupting natural environments for centuries. Deforestation and improper waste disposal has destroyed fish spawning grounds, introduced heavy metals to the ecosystem, and triggered rapid warming of the lake waters. Runoff water containing sewage and industrial waste threatened the public drinking water in Milwaukee in 1993. Additionally, Enbridge Line 5, a 645-mile oil pipeline in the Enbridge Lakehead System, now runs through the Straits of Mackinac. If struck, the pipeline has the capacity to spill across hundreds of miles of shoreline, taking years to clean up and decimating the ecosystem.

Chemical Waste

Previously relaxed environmental regulations allowed nearby industrial plants and mining operations to dump their waste into the Great Lakes without any repercussions. Resultantly, sludge at the bottom of the waterways and lakes of the basin contain myriad toxic chemicals ranging from PCBs to radioactive waste. The southern shore of Lake Michigan is lined with factories and is a primary source of the pollution.

Algal Blooms

The extent and duration of anoxia/ hypoxia [oxygen-depleted bottom waters that cause blooms] in the central basin continue to increase annually. The extensive deforestation has led to an increase in nitrogen, the leading cause of excess algal growth. Additionally, warming water temperatures, also due to deforestation as well as global warming, provides a prime environment for exponential growth. The algae depletes oxygen levels of the lake water, suffocating fish populations and breeding bacteria.

How You Can Help

Alliance for Great Lakes

The Alliance for Great Lakes works with scientists, policymakers, businesses, community groups and everyday citizens to protect and restore the lake.

Save the Dunes

Save the Dunes works to preserve, protect and restore the Indiana dunes and all natural resources in Northwest Indiana’s Lake Michigan Watershed.

Clean Wisconsin

Clean Wisconsin protects WI’s clean water and air on Lake Michigan and advocates for clean energy by being an effective voice in the state legislature.

Lake Michigan Shorelands Alliance

The Lake Michigan Shorelands Alliance is a collaboration of land trusts focused on accelerating the protection of significant resources in the Lake Michigan basin.

Northeast Wisconsin Land Trust

Northeast Wisconsin Land Trust works one-on-one with landowners to create individualized conservation agreements that leave a lasting legacy for the environment.

Sources:

Ed Makowski, “A History of Lake Michigan Wildlife,” Schlitz Audubon Nature Center, April 19, 2018, https://www.schlitzaudubon.org/2018/04/19/a-history-of-lake-michigan-wildlife/.