When you visit one of the Great Lakes, whether it’s a sandy beach or a rocky coastline, it’s hard to imagine how something so large could be affected so deeply by species. invasive alien, pollution or climate change. This special environmental report examines each of these threats.
It starts with the changes at the bottom of the food chain (at 1:00 am in the audio above.). With the invasion of zebra and quagga mussels, agricultural pollution and climate change, diatoms, microscopic phytoplankton, are disappearing. Without plankton, some organisms like diporeia are wiped out (at 3:25). Ultimately, that means there is less food for the fish.
The Great Lakes at Risk explores how many invasive species such as quagga mussels – the culprits primarily responsible for damaging the bottom of the food chain – have entered the Great Lakes and what remains to be done to stop their spread.
The documentary also examines efforts to keep invasive carp out of the Great Lakes (6:50), although those efforts might not be able to stop them.
The greatest source of pollution in the Great Lakes is phosphorus runoff from farmland. The nutrient nourishes the cyanobacteria. This is a harmful algal bloom that can harbor a toxin that can make humans and animals sick. This year, blooms were smaller in western Lake Erie, but scientists say that doesn’t mean the problem will go away (1:00 p.m.).
Other pollution issues include plastics that destroy beaches, harm wildlife, and enter Great Lakes drinking water and even beer (2:30 pm) Industrial and agricultural chemicals, combined with pharmaceuticals mix in a vast chemical soup that can combine to make more toxic compounds (17:54)
Perhaps the biggest pollution concern in Michigan is pollution that didn’t even happen. Environmentalists, Native American communities and a number of Great Lakes businesses want Enbridge Energy’s Line 5 closed (9:24 p.m.).
The effects of climate change are altering nature in several ways and you can see it most clearly in the lakes and streams that empty into the Great Lakes. Citizen scientists and fishermen note these changes in the behavior of aquatic insects and the absence of certain fish (31:30). Heavier rainstorms cause more flooding in some areas. Some cities are struggling to change the way they deal with urban runoff in an effort to reduce the flooding problem and the answer isn’t always bigger concrete pipes (36:25)
The biggest changes are probably yet to come. The Great Lakes themselves are warming in unpredictable and volatile ways. Lake Erie is the shallowest of the five lakes and is more sensitive to warming. Lake Superior is the largest and deepest of the lakes and it is warming as well, as are many of the largest lakes in the world. These changes include dramatic changes in the ice cover on the lakes with some years more than usual and some years much less (41:50).
Even with these changes, the Great Lakes region is faring better than other parts of the United States well for some people. Can we expect a migration of climate change in this region? (45:55)
Great Lakes at Risk: Invasive Species, Pollution and Climate Change is produced by the Environment Report. This is part of the efforts of the Great Lakes News Collaborative, which includes Bridge Michigan; Circle of blue; Great Lakes Now on Detroit Public Television; and Michigan Radio. You can access all reports here. These media work together to bring news and information to the public on the impact of climate change, pollution and aging infrastructure on the Great Lakes and drinking water. This independent journalism is supported by the Charles Stewart Mott Foundation.