Some of North America’s best wreck dives are located throughout the Great Lakes region; unfortunately, there’s a new threat that could have an impact on the number of fish and other animals you see while visiting these dive sites. That threat is a phenomenon known as the Great Lakes Garbage Patch.
Plastic Microparticles To Blame – The Great Lakes Garbage Patch
When you envision a garbage patch, images of empty water bottles, plastic grocery sacks, and other commonly encountered flotsam might come to mind. But like the garbage patches that plague the Pacific and Atlantic oceans, as well as those located off the remote coastlines of Antarctica, the Great Lakes garbage patch is mostly made up of particles that are smaller than two-tenths of an inch in size. Many of these particles are in fact microscopic. Lorena M. Rios Mendoza, who is a University of Wisconsin-Superior scientist who focuses her research on the impact of plastic pollution across the planet, led a study of the Great Lakes. Her group of researchers found between 1,500 and 1.7 million minuscule plastic particles per square mile in areas tested.
The concentration of microparticles in the Great Lakes garbage patch was found to be approximately 24 percent higher than the concentration of particulate found in the Southern Atlantic Ocean’s garbage patch. This is alarming not because particulate matter clogs the waterways, but because it is so small that aquatic animals ingest the particles and have no way to digest them. While some particles are small enough to be excreted along with other waste, many pieces of plastic trash are large enough to cause partial blockages or even full blockages of the animals’ digestive systems. Over time, even a slight blockage within the digestive tract can lead to serious illness and death.
Plastic debris concerns scientists mainly because it resists natural decomposition. Of the particulate matter collected during the recent study, about 85% of plastic debris pieces were small enough to go unnoticed by humans. Rios-Mendoza expresses concern over this not just because of the intestinal blockages small particles can cause, but because the chemicals that leach from plastic can cause harm to fish and other organisms, including human beings. In fact, any fish consumed may contain high amounts of damaging chemicals like BPA; research is ongoing to test fish and other Great Lakes aquatic life for exposure to these chemicals.
The Great Lakes are the world’s largest group of freshwater lakes, and they account for a stunning twenty percent of the planet’s freshwater surface. The National Wildlife Federation reports that factory waste, agricultural runoff, and pollution associated with development are playing a devastating role in damaging the Great Lakes ecosystem; now, with vast quantities of plastic making their way into the water, scientists are scrambling to uncover a solution for cleaning up pollution before it’s too late.
While microscopic pellets of plastic might be nearly impossible to clean up, larger pieces of debris could potentially be removed from the water, and for divers who enjoy the Great Lakes, cleanup efforts can consist of simply picking up any pieces of garbage discovered underwater or on shore. Communities along the lakeshores value the fish and wildlife that call these magnificent lakes home, and ongoing cleanup efforts are certain to make a positive difference – especially now that the true magnitude of the problem has been brought to light.