Sun Compass Orientation of Immature Bluegill

Publisher Website
Google Scholar
Abstract
Immature bluegills, L. macrochirus (389), were collected from Par Pond, a 1120 ha impoundment on the US Department of Energy''s Savannah River Plant near Aiken, South Carolina [USA] and tested individually by observing their directional movement from the center of a circular testing facility. Bluegills captured 10-20 m from shore in areas lacking extensive submerged vegetation swam in a direction which would have taken them to shore at the area of their capture; those taken from areas having submerged vegetation offshore swam in the direction opposite from shore. The directional responses of fish that were phase-shifted by 6 h demonstrated that they were using time-compensated sun orientation. Fish exposed to a predator oriented in the direction of shore in their training facility, but if no predators had been present during training, moved in the direction of deep water. Immature bluegills use their sun compass mechanism in oriented movements and the observed behavior is probably related to avoidance of their predators.

This publication has 3 references indexed in Scilit: