Life History Of The Yazoo Darter (Percidae: Etheostoma Raneyi), A Species Endemic To North-Central Mississippi
The Yazoo darter, Etheostoma raneyi, is restricted to tributaries of the Little Tallahatchie and Yocona Rivers (Yazoo River drainage) in north-central Mississippi. The species inhabits small, clear streams, many of which are spring-fed, and have a variety of substrate types including silt, clay, sand and gravel. In Morris Creek, a second-order stream in Lafayette County, Mississippi, E. raneyi was found in a diversity of microhabitats. Etheostoma raneyi is short-lived, with very few individuals living more than two years. Yazoo darters are sexually dimorphic, with males larger and more brightly colored than females. Both sexes become reproductively mature during the first year of life. The sex ratio of the Morris Creek population is female-biased. Like other members of subgenus Nunostoma, Yazoo darters use the egg-attaching spawning strategy. Batch fecundity of Yazoo darters is 52, and the average diameter of ova in this size class is 1.05 mm. Based on gonadalcondition, the spawning season lasts from March to June. Yazoo darters are the most abundant fish in Morris Creek.