Sexual harassment in live-bearing fishes (Poeciliidae): comparing courting and noncourting species

Sexual harassment by males has been reported from several live-bearing fishes (Poeciliidae) and has been shown to inflict costs on females. For example, poeciliid females have reduced feeding opportunities when accompanied by a male because females dedicate attention to avoiding male copulation attempts. Poeciliid species differ considerably in male mating behavior, such as the presence or absence of courtship. Courting males display in front of the females, but males attempting to sneak-copulate approach females from behind, that is, in the blind portion of heir visual field, and force copulations, which can be viewed as a male persistence trait. We predicted that poeciliid females need to be more vigilant in the presence of noncourting males, and costs of harassment by noncourting males might be stronger. In a comparative approach we examined the costs of male sexual harassment for females as reduced feeding time in 9 species of live-bearing fishes, including courting (Poecilia latipinna, Poecilia reticulata, Xiphophorus cortezi, Xiphophorus variatus) and noncourting species (Poecilia mexicana [surface- and cave-dwelling form], Poecilia orri, Gambusia affinis, Gambusia geiseri, Heterandria formosa). In all species examined except for the cave form of P. mexicana, focal females spent significantly less time feeding in the presence of a male than when together with another female. The time females spent feeding was found to significantly decline with increasing male mating activity (sum of all sexual behaviors), but there was no support for the idea that females would spend more time feeding in the presence of courting males compared with noncourting ones.