TRAVERSE CITY, MI (AP)-- Scientists say an invasive European snail that carries parasites fatal to some aquatic birds is spreading across the Great Lakes region.
Researchers with 10 universities and the U.S. Environmental Protection Agency have detected faucet snails in many new locations over a three-year period.
The snails harbor intestinal flukes that kill ducks and water birds known as coots. When birds eat the snails, the parasites attack the birds' internal organs.
The faucet snail is about a half-inch in height at full size. It ranges in color from brown to black and has a distinctive whorl of concentric circles resembling tree rings on its shell opening cover.
It spreads easily and is hard to kill.
Carl Ruetz of Grand Valley State University's Annis Water Resources Institute said Monday the discovery was made as scientists monitored the condition of Great Lakes wetlands.
The research team also has helped locate and combat invasive aquatic plants. It plans to report soon on the spread of exotic fish species.
"This is another example of how our natural systems are constantly at risk, and why it is so important to remain vigilant, as is being done through this basin-wide monitoring effort," said Alan Steinman, director of the institute.