79-7 Sat Jan 2 Effect of temperature and group size on the collective response of fish to a threat Kuruvilla, M*; Berdahl, A; Dell, A; Knouft, J; University of Washington; University of Washington; National Great Rivers Research and Education Center; Saint Louis University mariakur@uw.edu
Ectothermic animals, such as fish, are more vulnerable to fluctuations in water temperature than endothermic predators such as bears or humans. This asymmetry in the effect of environmental conditions on behavior can influence predator prey interactions. In order to investigate whether fish are able to compensate for their harsh environment by using social information, we recorded the swimming and response to loom stimulus of golden shiners (Notemigonus crysoleucas) of different group sizes. Group sizes varied from 1 to 32 fish and the water temperature varied from 9°C to 29°C. Using computer vision and tracking software, idtracker.ai, we analyzed the trajectories of every individual. We see that the speed and acceleration of the fish to respond to the stimulus increase with increase in temperature and decrease with increase in group size. Latency to respond to the stimulus decreases with increase in temperature as well as group size. Distance to the center of the tank decreases with increase in temperature. Average nearest neighbor distance also decreased with increase in group size which suggests that the fish were schooling more tightly in bigger group sizes.