Eutrophication is the process whereby a waterbody gradually becomes enriched with organic and mineral material, resulting in increased plant growth. The combined effect of these cultural stresses are that water bodies become overly rich in nutrients, causing algae to grow rapidly and the oxygen supply to be depleted. Lake Erie was the most eutrophic of the Great Lakes in the 1960s, and many areas were described as oxygen starved, and choked with blue-green algae (Francis et al. 1985). However, substantial declines in the phosphorus content of laundry detergents and increased capacity of sewage treatment plants to remove phosphorus from waste water have resulted in substantial declines in the phosphorus inputs to Lake Erie since the 1970s. This, and the introduction of zebra mussels to the Great Lakes in the 1980s has resulted in a considerable improvement in Lake Erie's water quality as seen throughout Long Point Bay. While the Outer Bay is mesotrophic, the Inner Long Point Bay is considered to be eutrophic (Leach 1981). However, it is this enriched nature of the Inner Bay that enables it to support dense stands of emergent macrophytes, thereby providing habitat for waterfowl and fish. Also, marsh vegetation slows the eutrophication process by absorbing or inactivating nutrients. Therefore, there is little threat that the Inner Bay will become over-enriched at the present level of Lake Erie water quality and nutrient inputs from Big Creek.
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