Hepfer, Paige, Ecology Program, Susquehanna University, Susquehanna University, 514 University Ave., Selinsgrove, PA 17870, hepfer@susqu.edu; Ashcraft, Sara A, Freshwater Research Institute, Susquehanna University, 514 University Ave., Selinsgrove, PA 17870, ashcraft@susqu.edu.
Freshwater sculpin are a small-bodied, benthic species found in cool- to cold- water rocky streams. They can be a useful environmental indicator due to their partial tolerance to turbidity and siltation and intolerance to warmer temperatures, chemical pollution, and acidification. Mottled Sculpin Cottus bairdii (Girard, 1850) and Slimy Sculpin Cottus cognatus (Richardson, 1836) are two species overlapping in distribution within West Branch Susquehanna River watersheds. The suggested identification protocol for these species is to examine distribution maps, use a dichotomous key to make an initial identification, then review additional characteristics to confirm. This can be a time-consuming process in the field and can make accurate identification challenging. In addition, due to its size, it can be difficult to determine morphological differences in a field setting, along with among-species variation and between-species overlap in characteristics. We developed a protocol and collected vouchers in the field to determine how accurate our sculpin identifications are for the Loyalsock Creek, Pine Creek, and Kettle Creek watersheds along with smaller West Branch Susquehanna River tributaries. Our field identification was compared to a more thorough laboratory examination of vouchered specimens which included additional traits. We fine-tuned traits based on year 1 data and completed a second season using our new protocol. Year 2 protocol was helpful in accurately identifying specimens by analyzing the field and lab traits that we will finalize for year 3 field season identification. Our next steps are completing caliper measurements to target variation in morphology and investigating species distribution for these drainages with our finalized protocol targeting established gaps.
Freshwater, Sculpin, Sampling Methods, Species Distribution