Male courtship pheromones suppress female tendency to feed but not to flee in a plethodontid salamander

Abstract

Female sexual receptivity is a behaviour at the crux of mechanistic and evolutionary perspectives of reproductive behaviour. To gain insight into the general processes by which a male persuades a female to mate with him, we tested whether the courtship pheromones of the red-legged salamander, Plethodon shermani , dampened female defensive or ingestive behaviours. Females did not sprint significantly shorter distances to evade startling stimuli when experimentally treated with pheromone solution compared to a control. However, females did consume 25% fewer fly larvae when treated with pheromone compared to a control. The female's maintenance of normal defences suggests a behavioural state that is unresponsive or resistant to pheromone stimulation, but the change in feeding activity indicates that suppression of female hunger is beneficial to male mating success. Together, these results indicate that male courtship pheromones may augment female receptivity by modulating the expression of other competing or inhibitory motivated behaviours.