Thermal Stress Leads to Behavioral Shifts in two Species of Slippersnail, Crepidula fornicata and Crepidula plana

Anthropogenic climate change, while not only increasing overall ocean temperatures, has also increased the variability in temperature that intertidal organisms experience. These organisms are put under increasing stress every year and need to adapt to these changes. In order to better understand this response of intertidal organisms, we studied the response to thermal stress of two species in the slipper snail genus, Crepidula. Using C. fornicata and C. plana collected from Beverly, MA, we labeled and analyzed the movement and feeding patterns of the Crepidula in three separate tanks: cold, control, and hot. All tanks started at 18°C and the control tank remained constant throughout the experiment, while the cold and hot system temperatures were changed daily, reaching 6°C and 26°C, respectively. We found that both species had a significant increase in feeding rate in the hot system, yet rates in the control and cold systems had no difference. In terms of movement, we also found that C. fornicata were significantly more likely to move out of their petri dish than C. plana. Temperature also affected movement, with cold treatment individuals moving significantly less than the other treatments. The increasing number of very cold days could affect the ability of Crepidula to consume the food they need to survive, and could limit their ability to move to a more favorable area. Understanding how Crepidula respond to variable temperatures is important in predicting how marine life, in general, will respond to rising ocean temperatures and how organisms will have to adapt in order to survive.