Mate-seeking behavior in the calanoid copepod Eodiaptomus japonicus

Abstract

Abstract We present here the first report of the mate-seeking behaviors of the calanoid copepod Eodiaptomus japonicus. Analyses of three-dimensional (3D) recordings revealed that males exhibit both homo- and heterosexual pursuit patterns, with no obvious increase in swimming speed during seeking. Males appear to use hydromechanical signals to seek female locations and detect them from up to 6 mm away, mainly from below. Males always exhibit several small hops to adjust their position to an optimal for catching a mate. In homosexual encounters, the two individuals separate within 1 s, whereas the average copulation duration in heterosexual mating events persists for ∼2.9 min. Females display a shaking-off male behavior in all heterosexual pursuit events, indicating the existence of mate choice. This mate choice may result in enhanced offspring quality and decrease the pairing time thereby reducing predation risk.