Carpet of algae on bottom of Sebago Lake near Indian Island, near the Portland Water District non-contact zone. Long-time lake residents remember this area as having a bottom of clean boulders and leaves prior to the 1990s. Photo taken August 26, 1997 by Sonny and Helen McAlpin, Underwater Photo & Video.
12. Analysis of impacts of lake-level management on aquatic and terrestrial wildlife resources of Sebago Lake.

FOSL requests the EIS analyze the impacts of the present unnatural lake regulation on wildlife. FOSL believes the present lake regulation may be harming the biological diversity of the Sebago Lake wildlife.

Because FOSL fish study requests are included in these scoping comments this wildlife study request refers to important lake fauna except fish. Mussels, crayfish, benthic macroinvertebrates (aquatic insects), amphibians, annelids, birds and mammal studies should be included. Mussel habitat has been altered with the change from a sandy bottom to a nutrient rich algaeic lake bottom. Mussel populations appear to be lower than prior to 1987.

Crayfish stranding, freezing and dessication occurs during winter drawdowns on unnatural severity. These crustaceans are an important part of the food chain. In the years since 1987 when S.D.Warren aggressively lowered the lake in the winter for bonus hydropower production profits, FOSL believes the lake's crayfish population was reduced.

Benthic macroinvertebrate populations are altered by lake regulation. The cleaner and more oligotrophic a lake is the greater the populations of certain key aquatic insects. FOSL divers at Buoy 85 south of Fryes Island have sampled the lake bottom sediment and found in one handful of bottom sediment a half dozen long thin worms. This richness of annelid fauna in the bottom sediments was never noticed before 1987 in the pristine areas of Sebago Lake.

Reduced biodiversity is harmful to the lake ecology and water quality. FOSL does not support unnatural winter drawdowns. Significant lowering of the water level after hard freezing temperatures can cause complete mortality of some species. Many benthic macroinvertebrates are extremely sensitive to freezing. Amphibians cannot relocate once winter arrives. Severe lowering of the lake has occurred after 1987. The licensee altered water level management to capitalize on increased hydroelectric profits without regard for the impacts on wildlife. Since the 1997 compromise went into effect the licensee has dictated lake level management that favors reaching the 261 msl or lower targer, 2 in 9 years, in late December. For ecological and beach accretion reasons, lowering of the lake to the 25th percentile and lower must occur before Nov. 1. The post-1987 management of Sebago Lake has caused a shift in the timing of the lake's natural highs and low water levels.

Regarding wildlife in particular the Lake Managers Handbook, a New Zealand government publication (Mark and Kirk 1987) states: "No other single factor affects wildlife use of a lake as much as fluctuations in water level. Water levels determine feeding opportunities, timing of breeding, success of breeding and the area of the habitat available to each species. A reversal of the natural water level regime has a very significant effect on wildlife."

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