Snail Darter - Introduction

Introduction

The snail darter (Percina tanasi) is a rare species found in East Tennessee freshwater. It is a part of the perch family (family Percidae) of the order Perciformes. Discovered in 1973, the snail darter was listed under the U.S. Endangered Species Act of 1973 by 1975 and was involved in a legal controversy leading to a Supreme Court ruling to approve the completion of Tellico Dam, which posed a risk of extinction for the snail darter by blocking its migratory route. In 1978, the U.S. Fish and Wildlife Service, Tennessee Valley Authority (TVA), and Tennessee Wildlife Resource Agency launched a recovery plan to preserve the snail darter by transferring the species to other river systems. Its native range was originally in the lower parts of the Little Tennessee River, the Sequatchie River, and in Chickamauga Creek but was later eliminated from the Little Tennessee River by the completion of Tellico Dam. The species was then transplanted into the Hiwassee River in southeastern Tennessee. The species inhabits large creeks or deeper portions of rivers and reservoirs with gravel and sand shoals substrate. The snail darter spawns between February to mid-April with the female producing 600 eggs which drift downstream. Juveniles occupy slack water habitats and migrate upstream to the breeding ground. The lifespan of the snail darter ranges between 2 to 4 years. The snail darter adult length ranges between 55 to 90 mm (2.2 to 3.1 inches). The species’ diet consists mostly of snails and insects (caddisflies, midges, and blackflies). Snail darters have camouflage dorsal patterns and burrow in the substrate to conserve energy and hide from predators. They are largely preyed upon by banded sculpin (Cottuss carolinae). The word Tanasi derives from capital of the Cherokee Nation located on the Little Tennessee River where the species was discovered. The species was relisted as threatened in 1984 after being successfully transplanted into other river systems.