Death’s come knocking a last time for the splendid ivory-billed woodpecker and almost two dozen other birds, fish and other species: The U.S. government is declaring them extinct.
It’s a rare move for wildlife officials to give up hope on a plant or animal, but government scientists say they've exhausted efforts to find 23 species, including the aforementioned woodpecker, Bachman's warbler and eight kinds of freshwater mussels.
One species was found in Indiana – the tubercled-blossom pearly mussel, which was last seen in 1969, according to the U.S. Fish & Wildlife Service. The mussel was found in large rivers, shallow sand and gravel shoals with rapid currents; it was particularly numerous in the Ohio River Valley.
Scientists say climate change threatens to make extinctions more common as it adds to the pressures facing imperiled species.
The factors behind this latest and largest batch of extinctions vary — urbanization, water pollution, logging. In each case, humans were the ultimate cause.