Meeting Abstract
P3.54 Thursday, Jan. 6 Quantifying Maneuverabilty in Bluegill Sunfish GERRY, S.P.*; LIAO, J.; IVES, C.; ELLERBY, D.J.; Wellesley College; Wellesley College; Wellesley College; Wellesley College sgerry@wellesley.edu
Bluegill sunfish (Lepomis macrochirus) from a littoral habitat exhibit morphological features indicative of maneuverability as compared to their pelagic counterparts. Littoral bluegill have a deeper, broader body shape; and fins located further from the center of mass. The goal of this study was to investigate if this morphological variation translated to a difference in maneuverability performance. We hypothesized that littoral ecomorphs would be more effective at maneuvering as shown by a faster course transit and higher accelerations and decelerations while traversing an obstacle course. A total of 19 bluegill (10 littoral, 9 pelagic; 7 trials per fish) were recorded using high-speed video while swimming through an obstacle course containing a series of vertical barriers mimicking a stand of littoral macrophytes. The snout and center of mass (COM) of the fish were tracked frame-by-frame using ImageJ. Comparing data from all trials, littoral bluegill completed the course faster than pelagic bluegill (1.28s v. 2.44s, P < 0.05), followed a shorter path through the course (0.28m v. 0.29m, P < 0.05) and maintained a higher COM velocity (3.72m s-1 v. 3.00 m s-1, P < 0.05). Confining the analyses to the maximal performances of each fish, differences were detected only for angular deceleration which was greater for littoral ecomorphs (-131,000 degrees ms2 v. -67,500 degrees ms2, P < 0.05). Over the course of multiple trials littoral bluegill were more effective overall at completing the maneuvering task, yet maximal performances were similar in both ecomorphs. This suggests that either the ecomorphs are similar in maximal maneuverability performance, or that performances approached the maxima possible while performing this specific task, but this task may not have elicited the maximum possible performances for the individuals concerned.
