Experimental data supporting the interactive effects of mating receptivity and courtship pheromones on the scent preferences of female red-legged salamanders

The behavioral and endocrine responses elicited by pheromones are highly
dependent on the sex and physiology of the receiving individual. In the
red-legged salamander (Plethodon shermani), male courtship pheromones
influence female mating behavior and regulate the timing of courtship.
Pheromones also modulate female feeding behavior and scent preference in
this species, but little is known about how the physiological state of
females may influence their olfactory preferences. The aim of this study
was to use laboratory trials to investigate whether differences in female
receptivity influence the effect pheromones have on female scent
preference. Our first experiment showed that pheromone treatment
significantly increased the time females spent on male-scented substrate
compared to both female scent and water. In a second experiment, female P.
shermani with differing levels of mating receptivity were treated with
either saline or pheromone and assayed for the relative time spent on each
of three scents (male scent, food scent, and water). When females were
treated with saline, their preference for male scent was positively
correlated with mating receptivity. Application of pheromone also
increased preference for male scent, but this effect was greater in
females with lower receptivity. Pheromone treatment also decreased
preference for food scent and was significantly pronounced in females with
higher receptivity. These results suggest that courtship pheromones in P.
shermani may have dual roles in regulating female preferences based on
baseline mating receptivity, further suggesting a complex interplay
between male courtship pheromones and female preference dynamics.