Remember the snail darter (or, more likely, hearing about it)? In 1975, the Endangered Species Act temporarily halted construction of the Tellico Dam on the Little Tennessee River because it would endanger the habitat of the snail darter, a three-inch fish (shown above).
The snail darter will be taken off the list, reports Dino Grandoni in the Washington Post. Fish and Wildlife Service officials have announced that “the fish is no longer at risk of extinction after being transplanted to other rivers and discovered in locations beyond the dam’s reach,” says the Post.
The Endangered Species list has hundreds of species that are protected. Few have ever come off the list. “During its half-century on the books, the Endangered Species Act is credited with saving the bald eagle, American alligator, humpback whale and now the snail darter,” says the Post.
Some facts about the controversy and the recovery of the snail darter:
- The dam was built anyway, because Congress intervened, overriding the Endangered Species Act in this case.
Image by Lisa Chamberlain, licensed under Creative Commons. - The snail darter may not have been endangered after all. The Fish and Wildlife’s proposal to remove the snail darter says:
“Initially thought to require shallow, unimpounded portions of river to survive (Starnes 1977, pp. 21–23), snail darters were later found in the impounded but flowing upper sections of mainstem Tennessee River reservoirs (Hickman and Fitz 1978, p. 80). Snail darters were found in shoals at a depth of 1 to 3 feet (ft) (0.3 to 1 meters (m)) (Starnes 1977, pp. 21–33; Ashton and Layzer 2010, entire). Snail darters have also been found on gravel and cobble patches in up to 25 ft (7.6 m) of water with regular captures at 10 to 15 ft (3 to 5 m) deep (Ripley 1976, entire; Hickman and Fitz 1978, pp. 80–83; Matthews 2017, pers. comm.; Matthews 2019, pers. comm.). In addition to large river habitats, snail darters also occupy the lower reaches of larger creeks. . . . “
The Fish and Wildlife Service also moved the snail darter to other rivers to create additional populations.
- The Tennessee Valley Authority (which operates the dam) has changed treatment of its tailwaters, creating better habitat for species that thrive in shallow water, such as the snail darter. From the proposal:
“[B]eginning in 1981, TVA began studies to improve conditions in the tailwaters of their dams. The cold, oxygen-deficient water released from the bottom of many of the dams created conditions that eliminated many fish and mussel species from these areas. Through the RRIP, TVA began implementing strategies to increase minimum flow, dissolved oxygen, and, in some cases, temperature, in the tailwaters of their dams beginning in 1991 (Bednarek and Hart 2005, p. 997).
Image of snail darter is from the Fish and Wildlife Service and is in the public domain.