Ashcraft, Sara, Freshwater Research Institute, Susquehanna University, 514 University Ave, Selinsgrove, PA, 17870, ashcraft@susqu.edu; Hepfer, Paige, Ecology Program, Susquehanna University, 514 University Ave, Selinsgrove, PA, 17870, hepfer@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. Sculpin are small-bodied fish, making it 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 field identifications are for the Loyalsock Creek, Pine Creek, and Kettle Creek watersheds. Field identification was compared to a more thorough laboratory examination of vouchered specimens which included additional traits. We are determining which traits overall are the most helpful to accurately identify specimens, how much variation occurs within each species for each drainage, and are developing a field identification protocol based on this information. We also plan to develop a more detailed species distribution map for these drainages.
Freshwater Fish, Lotic, Sampling Methods, Species Distributions