Saving the sturgeon: re-Introduction of lake sturgeon to the Tennessee River, Tennessee, USA

Summary

Lake sturgeon (Acipenser fulvescens), once native to the Mobile Basin including the Tennessee River, disappeared from Tennessee by the 1960s and cannot naturally recolonize the river today because dam impoundments block access from stable Mississippi and Missouri River populations. Following Clean Water Act-driven improvements and a 1988-1993 Reservoir Release Improvement program by the Tennessee Valley Authority that boosted downstream oxygen levels and aquatic life below Douglas Dam, a multi-agency recovery team formed in 1998 to restore a self-sustaining population to the upper Tennessee River Basin. In 2000, 41 radio-tagged two-year-old sturgeon were released into the French Broad River across three seasons of stockings, and after they thrived, the team scaled up egg collection from Wisconsin's Wolf and Wisconsin Rivers, using five females and five males per family group to maximize genetic diversity, with eggs hatched and reared at Warm Springs National Fish Hatchery and three partner facilities. The first major release, 1,441 fingerlings, entered the river below Douglas Dam on 19 July 2000; from 2000 to 2007 a total of 53,255 lake sturgeon were stocked, 85 percent as yearlings, with all fish screened for pathogens and marked by scute removal. Monitoring combines gill netting, electrofishing, telemetry, and collaboration with commercial and recreational fishermen, alongside a school education program begun in 2006. The project rated itself Partially Successful, since lake sturgeon do not mature until 12 to 25 years old and the oldest released fish, at 10 years, have not yet reached spawning age to demonstrate natural reproduction.