Variation in Fast Start Performance of Bluegill Ecomorphs


Meeting Abstract

P3.136  Friday, Jan. 6  Variation in Fast Start Performance of Bluegill Ecomorphs GERRY, S.P.*; ROBBINS, A.; ELLERBY, D.J.; Fairfield University; Wellesley College; Wellesley College sgerry@fairfield.edu

Bluegill sunfish (Lepomis macrochirus) from Lake Waban, MA exhibit variation in their morphology and swimming performance based on habitat. Pelagic ecomorphs have a relatively streamlined, fusiform body shape that correlates with greater steady-state swimming speed and energy economy. In contrast, littoral bluegill have deeper bodies with fins located farther from their center of mass to enhance maneuverability among the vegetation. Deeper body shapes have been associated with increased fast start performance in order to escape predators and capture prey. We hypothesized that the littoral ecomorphs would exhibit greater fast start performance compared to pelagic fish. A total of 27 bluegill (16 littoral, 11 pelagic) were caught by hook-and-line and their fast start performance analyzed from high-speed video recordings. Body shape appears to be a poor predictor of fast-start performance in these ecomorphs. Contrary to our expectations, pelagic bluegill have a higher peak velocity (ANOVA, p = 0.002), peak acceleration (ANOVA, p = 0.008) and angular velocity (ANOVA, p = 0.001) compared to littoral bluegill. Pelagic ecomorphs living among larger predators and foraging on mobile prey in the open water may be exposed to selection pressures that favor increased fast start performance. Future studies of fast-start performance in juvenile bluegill may provide a greater understanding of how these fish diverge in form and function to become either a pelagic or littoral ecomorph.

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