Presenter: Kyla Schmitt – Economics, Environmental Studies
Faculty Mentor(s): Alexis Barton, Reyn Yoshioka
Session: (In-Person) Poster Presentation
In Portland, Oregon, signal crayfish (Pacifastacus leniusculus) earn the title of “keystone species” by consuming otherwise-inaccessible detritus, which can then be passed up the food chain to various other species, and carving up riverbeds, an act which greatly influences aquatic habitat quality. This study questioned whether habitat factors impact signal crayfish health and behavior in the Tryon Creek Watershed. Overall, crayfish were disproportionately likely to be observed in locations with high human impact levels; silt/sand or boulder and cobble substrates; culverts, runs, and pools; and water 10-39 cm deep. Juvenile crayfish were disproportionately likely to be observed in locations with low human impact levels, silt/sand or cobble and gravel substrates, and water 0-19 cm deep. Unhealthy crayfish—specimens that were deceased, immobile, struggling, or consisted of severed appendages— were disproportionately likely to be observed in locations with culverts or riffles and water 0-19 cm deep. The study found no evidence for an established population of invasive crayfish in Tryon Creek, although further monitoring (particularly in the Tryon Cove area) is necessary to confirm this finding. The study’s analysis also suggested that human-caused ecosystem disruptions can seriously decrease the health and wellness of signal crayfish populations if not managed mindfully and holistically, pointing to a need for better waterway designs that benefit fish and crustaceans alike.