Re-introduction of the Citico darter, Little Tennessee River drainage, Tennessee, USA

Summary

The Citico darter (Etheostoma sitikuense), a Critically Imperiled and federally endangered fish confined to a roughly 3.5-km stretch of Tennessee's Citico Creek, is the fourth of the coordinated species targeted since 1986 by Conservation Fisheries, Inc. for reintroduction to Abrams Creek, where it had been extirpated by a 1957 chemical fish-removal project. Beginning captive work in 1992 with first stockings in 1993, the program has released Citico darters reared from wild-collected Citico Creek egg nests, using winter-conditioning of broodstock under controlled temperature and photoperiod to induce reproduction, though captive breeding remained only intermittently successful and non-essential to overall program goals. The reintroduced Abrams Creek population now reproduces and disperses at densities rivaling the Citico Creek source and has sustained itself without further stocking since 2002. Since 2003, over 3,500 darters have been stocked into the Tellico River under nonessential-experimental-population status, with wild reproduction observed nearly continuously since 2004 and multiple wild-spawned age classes routinely detected, though continued reintroductions are expected to be needed for several more years to match Abrams Creek's success. All fish undergo pre-transfer disease screening, and a genetics study tracks gene flow among the Citico, Abrams and Tellico populations of the darter and its three co-managed species to inform a future fish-passage strategy. The project rates itself Successful, citing established, self-sustaining, reproducing populations at both reintroduction sites.