Current Status and Distribution of the Strawberry Darter in the Tributaries and Mainstem of the Strawberry River Drainage

The Strawberry Darter Etheostoma fragi is endemic to the Strawberry River drainage and was recently elevated to the species level. A status survey was initiated during summer 2015. Thirty-two sites were sampled within the Strawberry River drainage, 16 on the main stem and 16 on tributaries. Sites were surveyed 4 times each throughout the summer using a kick-seine. A total of 106 E. fragi were encountered. E. fragi were sampled at 13 of 32 sites, including 8 tributary sites and 5 main stem sites. Data was analyzed using the software Presence, which calculates occupancy rate and probability of detection. A drainage-wide occupancy rate was estimated to be (mean± standard error) 0.40±0.09 and a probability of detection was estimated to be 0.51±0.08. Site type (main stem or tributary) was used in the second model, an occupancy rate of 0.33±0.13 and a probability of detection of 0.42±0.13 were estimated for main stem sites. In tributary sites an occupancy of 0.47±0.14  and a probability of detection of 0.50±0.11 were estimated. Compared to an occupancy rate based on historical data (0.73 ± 0.11), the current occupancy of sites might be a little lower. Occupancy rate appears higher in tributaries than the main stem.