THE PREREQUISITES FOR STRATEGIC BEHAVIOR IN BLUEGILL SUNFISH, LEPOMIS-MACROCHIRUS

Game theory often assumes that animals employ 'strategies' in which future behaviour is based on past interactions with known individuals. The question of whether animals have the cognitive ability to employ such strategies has seldom been examined empirically. In a laboratory experiment, bluegill sunfish, Lepomis macrochirus, were allowed to forage in pairwise association with five conspecifics to address two questions. (1) Do bluegill sunfish prefer to associate with individuals with whom they have foraged more successfully? (2) Do bluegill sunfish prefer familiar associates over unfamiliar associates? Results indicated that bluegill sunfish distinguish between known associates, and base their preference for such associates on relative success in prior foraging bouts. In addition, they are aware of a group member/non-group member dichotomy and choose to associate with known over unknown conspecifics. © 1992.