Sunday, August 14, 2005

Studying the Lakes

By Deb Price and Brad Heath / The Detroit News

Comment on this story Send this story to a friend Get Home Delivery

The range of threats facing the Great Lakes is so broad and complex that scientists still don't fully understand them all. A number of studies promise to offer additional details. Among those being planned or already going on:

Deep-water fish

Five projects are looking into the impact on the ecosystem of the decline of deep-water trout in the Great Lakes. They also are examining whether to re-establish large populations of the fish, and the best way to do so. The research is funded by the Great Lakes Fishery Commission. Researchers also will look at how to restore populations of the trout's prey -- bloaters, lake herring and sculpins -- whose populations also have dwindled. Trout now live almost exclusively in Lake Superior, where depths can reach beyond 1,000 feet. Initial findings are scheduled for release next year.

Lake Erie's dead zone

Researchers will spend two years tracking the effects of the lake's perennial "dead zone," a massive area of low oxygen levels that appears in the center of the lake each summer. The study, which includes dozens of researchers from the United States and Canada, aims to create better models of how the dead zone works and to figure out how it alters food webs and fish habitats in the lake. Lake Erie is the shallowest and most industrialized of the Great Lakes, so it feels the most acute effects from many environmental threats. It's hoped that what scientists learn in the lake can be applied to problems in the other lakes. The study is being conducted by the National Oceanic and Atmospheric Administration's Great Lakes Environmental Research Laboratory in Ann Arbor.

Food web disruption

Twenty projects are examining how invasive species are altering the Lakes' food chain, squeezing out the plants and animals native fish normally eat. Cercopagis and bythotrephes, small invertebrates about the size of a pebble, are carnivorous zooplankton that came into the Great Lakes in the last decade through ballast water discharged from oceangoing ships. These voracious eaters are feasting on native zooplankton that normally serve as the baby food for freshly hatched fish such as walleye, yellow perch and alewife. The research is sponsored by the Great Lakes Fishery Commission, the Great Lakes Fishery Trust and the sea grant agencies of the Great Lakes states. U.S. and Canadian researchers are expected to begin releasing findings at the end of this year.

Drugs in sewage

Oakland University researchers are looking at how prescription drugs, especially estrogen-rich birth control pills, affect the sexual development of male tadpoles. Because prescription drugs don't break down in water, they aren't broken down in the sewage treatment process. Oakland University researcher Linda Schweitzer is working with the Detroit sewage plant to see whether bombarding sewage with ozone might break down estrogen and other harmful elements in prescription medications that now are released into the Great Lakes waterways after the final stage of sewage treatment.

St. Clair spills

The U.S. Government Accountability Office, Congress' investigative arm, is looking at the frequency of chemical and petroleum spills on the U.S. and Canadian sides of the river since 1994 and the timeliness of notification procedures. The report, due in November, follows public outcry in Michigan over continued spills by Canadian companies. Environmentalists say the companies are responsible for hundreds of spills over the past two decades.

To learn more

A variety of Web sites offer detailed information about the issues facing the Great Lakes. Among them:

• Great Lakes Information Network, www.great-lakes.net: Offers background and current news on a wide range of threats to the lakes.

• State of the Lakes Ecosystem Conference, www.epa.gov/glnpo/solec: Includes the State of the Great Lakes reports, the most thorough and recent checkup on the Lakes' health, published by the U.S. Environmental Protection Agency and Environment Canada.

• EPA Great Lakes National Program Office, www.epa.gov/glnpo: Has information about federal policies and programs impacting the Lakes. (More information is available from Environment Canada, www.on.ec.gc.ca/greatlakes/)

• Great Lakes Environmental Research Laboratory, www.glerl.noaa.gov: Has links to current studies and data on the Great Lakes.