TOLEDO, Ohio — Scientists say there’s proof that one type of invasive Asian carp is spawning in a Great Lakes tributary.

A graduate student at the University of Toledo in Ohio discovered grass carp eggs last summer in the Sandusky River, which flows into Lake Erie.

Holly Embke’s findings have been published in the Journal of Great Lakes Research.

The U.S. Geological Survey previously reported that four young grass carp taken from the river had resulted from natural reproduction.