We have come a long way in improving the conditions in the Great Lakes since the low point in the late 1960s. For example, the overall contaminant picture has improved dramatically since the early-1970s, with significant declines in environmental concentrations of most of the critical contaminants for which data are available. Some bird species that were thought to have been lost forever from the region, such as the Bald Eagle and Peregrine Falcon, are beginning to return and even nest. The breeding populations of other species, including Osprey and Cormorants, are increasing. Fish communities are also improving, with species such as Lake Trout showing signs of recovery in most of the Lakes, including a self-sustaining population in Lake Superior.
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Notable Great Lakes Achievements!
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However, even with these improvements there is still a long way to go. We must recognize that although large percentage reductions have been achieved for many contaminants in comparison to peak levels, an additional ten fold reduction may be needed to reach acceptable levels of risk. Some contaminants that have been banned in the Great Lakes region are still being transported into the region from long distances via the atmosphere. Equally important are the non-chemical stresses on the ecosystem such as competition from exotic (or non-native) species, habitat loss and the widespread trend towards suburban sprawl.
Much data and information have been, and continue to be collected and analyzed in order to determine “are the Great Lakes healthy?“. This process of assessing the state of the Great Lakes ecosystem is part of the science portion of the Great Lakes 2000 Program. In determining the health of the Great Lakes indicators are widely used to determine the health of a system. For example, doctors use indicators such as blood pressure and weight to gauge human health; economists use indicators such as interest rates and housing starts to assess the health of economies. One way to determine the status of the health of the Great Lakes ecosystem is to use indicators which address a spectrum of conditions, ranging from the health the living components of the system (including humans) to the stressors and the activities that cause them. Ecosystem health indicators reflect ecosystem quality or trends in quality. However, ecosystems are inherently complex, so that no one indicator (or even suites of indicators) can be completely representative of all possible conditions.
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