Conservation assessment of the Yazoo Darter (etheostoma raneyi)
We summarized all known historical and contemporary data on the geographic distribution of Etheostoma raneyi (Yazoo Darter), a range-restricted endemic in the Little Tallahatchie and Yocona rivers (upper Yazoo River basin), MS. We identified federal and state land ownership in relation to the darter’s distribution and provided quantitative estimates of abundance of the species. We also quantified sex ratio and mean size of males and females, summarized abiotic and physical characteristics of streams supporting the species, and characterized the fish assemblage most often associated with the Yazoo Darter. Yazoo Darters are generally limited to headwater streams, have a female-skewed sex ratio, and have larger males than females. Individuals in the Yocona River drainage are larger than in the Little Tallahatchie River drainage. Abundance was highly variable among streams within the two major drainages, but was similar within and between drainages. Yazoo Darter habitat in the Little Tallahatchie River drainage has some protection because many streams supporting this species are on land managed by federal or state agencies. Streams with Yazoo Darters are far less common in the Yocona River drainage, have almost no protection, and face growing pressure from urban expansion. For these reasons, management action is urgently needed for Yocona River populations.