Ohio fish, mussel among 21 species now extinct, removed from endangered list

It was added to the endangered list in 1975 and its last confirmed sighting was in 1957. They were kept on the endangered list until now so that if they were found again they would get automatic protection.

A total of 18 of these fish were found, the first in November 1943, and all of them in a small section of the Big Darby Creek, a tributary of the Scioto River, according to the university.

Not much was known about this fish, but the U.S. Fish & Wildlife Service said it would be a bottom feeder that used its barbels to find aquatic invertebrates. Scientists also believed they spawned upstream in the summer and move downstream in the fall.

A second delisted species was the tubercled-blossom pearly mussel. Once abundant throughout all the major rivers of the eastern U.S. and southern Ontario it was particularly numerous in the Ohio River Valley, according to the U.S. Fish & Wildlife Service.

It was listed in 1976 and its last confirmed sighting was in 1969.

Deforestation and intensive agriculture contributed to its decline, as well as the building of dams and reservoirs and pollution from agricultural and industrial runoff.