Male mating strategies under predation risk: do females call the shots?

Many authors have reported that, under elevated risk of predation, male guppies (Poecilia reticulata) alter their behavior from courtship to forced copulation (gonopodial thrusts not preceded by sigmoid displays). This shift is presumed to benefit the brightly colored male, whose intense courting activity might otherwise increase his risk of detection and attack by predators. However, there is some evidence that females engaged in reproductive activity with males may be even more vulnerable to predators than the males themselves, which suggests an alternative hypothesis: females in high-risk situations are less receptive to male courtship, and this leads males to change their behavior. We tested this hypothesis by providing either males and females separately or both sexes concurrently, with information about elevated predation risk from a cichlid (Crenicichla sp.). We found that when only females were provided with information about increased risk, males performed fewer courtship displays and fewer thrusts. They did not perform more forced copulations in any treatment group. Nonetheless, our results suggest that the female's perception of predation risk can be at least as important as the male's in changing male mating behavior.