Social overstimulation reduces subsequent aggression inBetta splendens

Abstract

This paper examines the waning of intense aggressive behaviors in Siamese fighting fish subjected to continuous visual social stimulation. Damaging biting during subsequent fighting was dramatically reduced in fish which had been surrounded for several weeks by conspecifics, even though the overstimulated fish performed only opercular and fin displays to the fish surrounding them, not biting. The latency to opercular display was diminished, but the rate once opercular display began was not significantly different. In the 18 encounters observed, a socially overstimulated fish never dominated a control fish. This result suggests a visually mediated mechanism, which reduces biting tendency when there is prolonged, inescapable visual exposure to mildly aggression-releasing stimuli similar to those which trigger biting in live encounters. © 1994 Wiley-Liss, Inc.