Male Courtship Pheromones Affect Female Behaviour in the Swordtail Characin (Corynopoma riisei)

Abstract

Pheromones constitute an important cue used by both males and females during courtship. Here, we investigate the effect of male pheromones on female behaviour in the swordtail characin (Corynopoma riisei), a species of fish where males have a caudal pheromone gland which has been suggested to affect female behaviour during courtship. We subjected female C. riisei to male courtship pheromones and investigated the effect on both female behaviour and brain serotonergic activity levels compared to a control group. While no difference in serotonergic activity was found, the pheromone‐treated females showed lower stress levels compared to the control group. Furthermore, pheromone‐treated females increased locomotor activity over time, while a decrease in locomotor activity was observed in the control group. These results suggest that the male courtship pheromones may serve to reduce female stress and increase female activity, possibly to aid males in gaining access to females and facilitating sperm transfer.

Differential Effects of Sex Pheromone Compounds on Adult Female Sea Lamprey (Petromyzon marinus) Locomotor Patterns

“…This is consistent with our previous studies, in which ovulated females become arrhythmic in their locomotor activity when exposed to SMW in semi-natural field conditions (Walaszczyk et al, 2013). Although these results are also congruent with previous literature in other species documenting that sex pheromones can affect locomotor activity amounts in insects (August, 1971;Rust and Bell, 1976;Hawkins, 1978;Pontes et al, 2014) as well as fish (Bjerselius et al, 1995;Amcoff et al, 2014), we have provided a rare example of how a specific, exogenous chemical cue can alter not only the amounts of activity but also the overall pattern of locomotor activity in a vertebrate species.…”

Social behaviors as welfare indicators in teleost fish

“…Considering that pheromones play a fundamental role in social communication, their importance in Characiformes has been assessed in two species. In swordtail characin Corynopoma riisei, evidence suggests that male sex pheromones from gill and anal fin glands induce behavioral changes in females, reducing stress and increasing female courtship behavior, thus facilitating reproduction ( 86 , 87 ). In A. anisitsi , since gill glands are present in males with higher gonadosomatic index, they have been suggested as indicative of sex maturity ( 88 ).…”