Meeting Abstract

82.4  Monday, Jan. 6 11:15  Modeled predator accuracy predicts capture success in three centrarchids KANE, E.A.*; HIGHAM, T.E.; University of California, Riverside; University of California, Riverside ekane001@ucr.edu

Prey capture is critical for survival and reproduction, and for suction feeding fishes, success likely depends on the ability to correctly position and time the strike (accuracy). Despite this, we currently lack the ability to quantify accuracy when predator and prey are unconstrained in attack or escape behaviors. We applied a predictive model of suction hydrodynamics to calculate predator accuracy during semi-natural capture behaviors using 3D kinematics of three centrarchid fishes (Micropterus salmoides, Lepomis cyanellus, Lepomis macrochirus) capturing evasive and non-evasive prey. Capture success was >90% for non-evasive prey, but evasive prey responded to predators using a fast start, resulting in success ranging from 64% (L. cyanellus) to 96% (M. salmoides). The greatest ram speeds and gape sizes were observed in M. salmoides capturing evasive prey, resulting in the largest ingested volume of water (IVW). Only M. salmoides and L. macrochirus modulated IVW shape across prey types. The greatest and worst accuracies were observed for L. macrochirus capturing non-evasive and evasive prey, respectively, the only species where differences across prey types were observed. We conclude that capture success is increased when predators accurately control the position and timing of their strike and elicit fewer prey escape responses. In addition, predator accuracy is a useful metric of capture performance. Differences in accuracy reflect differences in ecological specialization that affect predator approach strategy and suction performance, and highlight the ability of each predator to capture certain prey types. This application of the IVW model elucidates differences in semi-natural capture strategies that can be used to generate hypotheses of prey capture evolution.