Field Note # 7: State Of The Great Lakes 2009 Highlights Report

Field Note #7 June 23, 2009
by Aurora Harris



Today I read about all the yucky stuff that's being dumped into our Great Lakes like used technology and old prescription drugs. The used technology includes televisions, phones, cell phones and old computers. After conducting a bit of research today on the Great Lakes, I found a 2009 report on http://binational.net/solec/sogl2009_e.html.
The report is a joint effort of the United States' Environmental Protection Agency and Environment Canada. When you click on the link, you will be able to download the latest and past reports about the status of the ecosystem, invasive species, effects on human health, contaminants and more.

At the link below, on pages 6-7, there is a report that 99% of freshwater mussels have been wiped out.
http://binational.net/solec/sogl2009/sogl_2009_h_en.pdf.

An excerpt from the 2009 report on Biotic Communities states:

Overall, the status of biotic communities varies from one lake to another, with Lake Superior generally having a more positive status than the other lakes. Indicators that measure lower food web components generally show more negative status and trends, and most of these can be related back to the impacts of invasive zebra and quagga mussels. Some indicators that focus on higher food web components are more positive and highlight the successes that can be achieved as a result of long-term restoration and protection efforts.

Benthic Organisms: Bottom-dwelling, or benthic, aquatic organisms are important to, and indicative of, aquatic ecosystem health. The diversity of benthic organisms in Lake Superior, Lake Huron, and Lake Michigan is typical of nutrient-poor, oxygenrich conditions. In contrast, the community of benthic organisms in Lake Erie is more typical of an aquatic ecosystem with low oxygen, nutrient-rich conditions.

Diporeia is an aquatic invertebrate that is an important food source for preyfish, and its populations have declined drastically in all lakes except Lake Superior. The decline
began after the arrival of zebra and quagga mussels, but their continuing downward trend is far more complex. The continuing decline will have serious consequences for the
food web, and impacts are being observed in populations of preyfish such as whitefish, bloater and sculpin.

In the lower Great Lakes, over 99 percent of the native freshwater mussel population has been wiped out by the establishment of invasive zebra and quagga mussels. There are a few isolated nearshore communities of native mussels that are still reproducing, with coastal wetlands
acting as refugia for native mussels. Recent research onnative mussels in the St. Lawrence River shows that aftera period of time following an invasion, the numbers ofnative mussels in open waters may stabilize and natural reproduction may resume.