Reproductive Characteristics of the Turquoise Darter (Etheostoma inscriptum) in the Upper Piedmont of South Carolina

Sex ratio, fecundity, gonosomatic indices (GSI), and time of spawning were examined for the Turquoise Darter (Etheostoma inscriptum) from January through June 2009. Approximately 30 specimens per sample were captured and examined in roughly three-week intervals. Additional sex ratio data were collected on 314 specimens from 3 to 13 March 2009. Sex ratio favored females 1.8∶1. Male weight and length were both found to be significantly greater than those of females. Peak GSI for males was the 2 April sample (1.1%), declining considerably by 19 June (0.4%). Peak GSI for females occurred 23 April (12.83%) followed by a decline through May, and continued to decline through June, when spawning appeared to end. Fecundity analysis showed a continuum of ova maturation during the spawning period with annual fecundity estimates ranging from 122 to 235 ova/yr. GSI and fecundity analysis together support that spawning in E. inscriptum initiates near mid April and continues until June in a series of multiple spawns. These previously unknown life history aspects of E. inscriptum are a valuable asset in management applications for the species.