Meeting Abstract

23.5  Wednesday, Jan. 4  Making waves: Quantitative analysis of information transmission in schooling fish CHICOLI, A*; LUN, Y; BUTAIL, S; COOMBS, S; PALEY, D; University of Maryland, College Park; University of Maryland, College Park; University of Maryland, College Park; Bowling Green State University, Ohio; University of Maryland, College Park

Benefits of schooling behavior are often cast in terms of predator evasion. The collective response of fish to a predator is an extremely rapid, propagating wave of visual and hydro-acoustic information, also known as the ‘Trafalgar effect’. The alignment and density of the school is likely to play a role in this information transmission, although little is known of what interactions among group members lead to predator detection and group cohesion. In this study, we test the hypothesis that school cohesiveness improves the signal-to-noise ratio for intraschool transmission of threat information. Experiments were performed on Giant Danio (Devario aequipinnatus) in a no flow condition and a flow condition, to simulate a more naturalistic environment. Using a high frame rate camera recording at 400 fps and a tracking system developed by our lab, we are able to extract the position, orientation and shape parameters of each fish in the school. Using this data, we quantify the benefits of cohesive schooling in the context of signal detection theory. The results of this study will help improve our understanding of collective behavior and the mechanisms of information transmission in fish schools.