Habitat Use of the Tuxedo Darter (Etheostoma lemniscatum) at Macrohabitat and Microhabitat Spatial Sclaes

Underwater observation was used to quantify patterns of habitat use for the tuxedo darter (Etheostoma lemniscatum) throughout its range in the Big South Fork of the Cumberland River. Macrohabitat and microhabitat variables were recorded at 12 sites from July through early October in summer of 2008 and 2009. Probability of tuxedo darter presence at a site increased with available cobble substrate and shallow pool habitat. Preferred summer microhabitat included depths between 20 and 80 cm, velocities less than 0.1 m/s, and cover rocks with surface areas between 200 and 1400 cm(2). Although other variables may affect presence, tuxedo darter distribution was limited by the availability of suitable habitat. Due to environmental variation in annual flow regimes, our models describe habitat use during drought and during above average flows. Models from this study identify critical tuxedo darter habitats, which can aid recovery efforts by identifying potential monitoring and reintroduction sites.