Inhabiting moderate to fast-flowing rocky rivers, the Boulder Darter earns its common name by the habitat it prefers. The Boulder Darter is listed as federally endangered and is currently known only from the Elk River and a few larger tributaries to the Elk River in Tennessee and Alabama. Boulder Darters were previously known from Shoal Creek in Alabama (once a tributary to the lower Elk River before impoundment by Wilson Reservoir) but were last seen there in the late 1800s. Over the past century improvements in water conditions and regulations imposed by the CWA improved Shoal Creek significantly, making it a wonderful river and a perfect place to use as a NEP for the Boulder Darter. Since 2005 CFI has been stocking Boulder Darters into Shoal Creek, releasing over 5000 individuals over 7 years.
In 2009, CFI had the first evidence that the Boulder Darters were recruiting in Shoal Creek. In 2011 CFI was very excited that Boulder Darters were dispersing downstream. Boulder Darters were found as far as 3 miles down from their original stocking sites! Monitoring efforts extended into Alabama for the 2012 field season and CFI found the first Alabama Boulder Darter!