COLUMBIA, Tenn. (AP) -- Biologists have reintroduced an endangered mussel to Tennessee's Duck River.
According to the U.S. Fish and Wildlife Service, the last time the winged mapleleaf mussel was seen in the Duck was more than 20 years ago.
The mussel historically had a range from Minnesota to Arkansas. Today, there are only five known populations.
Last week, federal and state biologists placed 103 juvenile mussels back in the Duck River.
The 2-year-old mussels were propagated at Missouri State University.
The Duck River was selected as a reintroduction site, in part, because it already has a diverse mussel population.
And Tennessee already has long-term monitoring sites on the Duck that will track the winged mapleleaf mussels' progress. Biologists laser engraved numbers on the mussels to help identify them for study.