Abstract

Male Pimephales notatus produce sounds during aggression associated with the breeding season. Females were not found to produce sounds during this study. Males produced sounds while in the nest cavity, chasing other fish, and during escalated aggressive displays. We identified four sound types characterized by differences in pulse duration and interval, which may be part of a continuum of sound parameters. The sound types were produced singly, in series, or as complex sounds composed of various combinations of three of the sound types. Complex sounds were made under all behavioral contexts and by all males studied. The mechanism of sound production in this species is unknown.