Snail Darter That Halted 1970s Dam Construction Found to Be Misidentified

New research reveals the fish at the center of a landmark environmental case was not a distinct species or endangered.

The snail darter, a fish that temporarily blocked Tennessee's Tellico Dam in the 1970s, has been found to be part of a non-endangered species, the stargazing darter.
Yale researchers determined the snail darter was misclassified, citing it as an example of the 'conservation species concept,' where species are identified to advance broader environmental goals.
The fish's discovery led to a Supreme Court ruling in 1978 that halted the dam's construction under the Endangered Species Act, though Congress later exempted the project, allowing its completion in 1979.
The case has since become a symbol of how environmental regulations can be used to delay or block infrastructure projects, fueling ongoing debates about regulatory reform and overreach.
The snail darter was removed from the endangered species list in 2022, decades before the recent findings confirmed it was never a unique species.