High concentrations of mercury are damaging the loon population at Aziscohos Lake.

Renewable power from solar, biomass, geothermal, water and wind sources is a tiny but growing portion of our energy budget. Hydropower provides our most dependable, renewable energy and is considered by many to be clean. However, even “clean” energy sources can be environmentally damaging and polluting when abused.

Maine Renewable Energy and Maine Interfaith Power and Light promotes and provides “clean” electricity from Maine. Sadly, the group has been misled.

The consortium draws power from the Aziscohos Hydropower Project (a facility operated for Florida Power and Light), a facility that appears to contribute to the high blood level of mercury for loons in Aziscohos.

The level found in these birds is 20 times greater than levels recorded in loons from natural unregulated lakes with similar fauna.

Mercury is deposited from the atmosphere as elemental mercury, a comparatively benign form. Methyl mercury, a much more toxic form, is produced biologically by bacteria acting on elemental mercury in oxygen-poor lake sediments. If these sediments are not disturbed, the methyl mercury is mostly insulated from the lake ecology.

FPL’s management practices at Aziscohos Lake have caused the pool to be drawn down during the three winter months to levels 60 percent lower than in the years prior to the hydropower installation. The result of the deep winter drawdown and the leisurely refilling of the pool in late spring is that extensive bottom sediments are exposed and disturbed by wind and wave action. This releases methyl mercury, which then contaminates the aquatic food chain during the most biologically active part of the year.

In a recent study conducted by Environmental Consultant Services Inc. for the Aziscohos Lake Preservation Committee, mercury was measured and studied. As it passes up the food chain, it increases 50-fold in protozoans and dinoflagellates. Through mayflies and caddisflies to crayfish and small vertebrates, it is increased 6,000-to-18,000-fold. It is increased 30,000-to-40,000-fold in fish, and ultimately to loons at the top of the aquatic food chain, where it has been magnified by up to 400,000-fold!

This is something to worry about!

Anyone who appreciates wild Maine’s loons, mergansers, ospreys and eagles, and enjoys eating fish without being poisoned, should be concerned and motivated to act.

Mercury most definitely affects loons.

Loons are excellent parents. Typically, they bring 80 to 90 percent of their hatchlings to the flying stage (fledging), and that had been the case in Aziscohos up to 1997. Since then the percent of loons fledged on Aziscohos has plummeted.

In 2000, only 40 percent were fledged; in 2001, only 25 percent were fledged; and, last year, none were fledged.

Mercury may interfere with fledging. One view is that the chicks are more susceptible to preditation because methyl mercury makes them hyperactive. It’s been observed that chicks spend less time protected on their parents backs when the parents (and by extension the chicks) have elevated blood mercury levels.

Maine Interfaith Power and Light and Maine Renewable Energy should carefully evaluate power sources before publicizing them as “green” power. No supplier or aggregator should be awarded significant green energy price premiums for contributing to the destruction of the Maine loon population.

The Maine Council of Churches, which proclaims its interests in preserving the natural beauty of Maine’s woodlands and lakes, should join us in demanding change.

Green energy must be clean energy. The concept of alternative energy is too important to allow it to be used as a screen for environmentally damaging power producers to hide behind.

Alan W. Johnson and Donald M. Green are co-chairman of the Aziscohos Lake Preservation Committee in Portsmouth, N.H.

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