Scientists say they've confirmed the discovery of grass carp eggs in a tributary of Lake Erie.
Grass carp are among four species of Asian carp that pose a threat to the Great Lakes. The most feared are silver and bighead carp, which eat plankton and could destabilize food chains. But grass carp are also a problem because they eat huge amounts of valuable plants.
The Great Lakes Fishery Commission says state, federal and university scientists analyzed eggs collected from the Sandusky River in Ohio earlier this summer.
They've now concluded they were grass carp eggs.