Although once abundant, the yellowcheek darter population has undergone a rapid decline, decreasing by 75 to 90 percent since the 1960s (3) (6). The principle agent behind this decline was the creation of Greers Ferry Lake in 1962, which resulted in the inundation of downstream tributaries, creating deep pools with increased sedimentation and lower oxygen levels in the water. As an inhabitant of shallow, fast-moving streams the yellowcheek darter was displaced from much of its former range, moving upstream to less suitable areas of habitat. The species’ migratory behaviour was also disrupted, while the loss of downstream refugia made the species more vulnerable to droughts, resulting in the loss of many populations (7). Other threats, such as the channelization of streams for agriculture and human consumption, have isolated some populations, and a loss of genetic diversity has been observed due to inbreeding (3) (8).