Satellites eye Great Lakes invasive plant

Scientists say satellites are helping map the spread of an invasive plant that rapidly grows into dense stands seen as a threat to Great Lakes coastal wetlands. Researchers from Michigan Technological University, the U.S. Geological Survey, Boston College and the U.S. Fish and Wildlife Service used satellite data to map the U.S. coastline of all five Great Lakes to identify the extent of the invasive Phragmites australis, or common reed, located within 6.2 miles of the water's edge. The result is "a highly accurate data set that will allow national, regional and local managers to visualize the extent of Phragmites invasion in the Great Lakes and strategically plan efforts to manage existing populations and minimize new colonization," MTU researcher Laura Bourgeau-Chavez said. Phragmites is a threat because it can out-compete native wetland plants for resources, quickly dominating wetlands, the researchers said. It displaces native vegetation and reduces the quality of the habitat, they said, altering nutrients in the soil and water and decreasing the diversity of animals and plants that normally live there. The study showed Lakes Huron and Erie had the highest level of invasive Phragmites, with a smaller amount in Lake Michigan and a few stands in Lake Ontario and almost none in Lake Superior, the researchers said.