Do female Lake Eyre dragon lizards adjust courtship rejection behaviour under higher predation risk?

Abstract

Female resistance is expected to evolve when mating costs outweigh resistance costs. One potential cost of resistance is increased predation risk; however, the ability to compensate behaviourally may reduce these costs. In the Lake Eyre dragon, Ctenophorus maculosus , non-receptive females employ several rejection strategies, including lateral threat displays and flipping over, to prevent superfluous matings. C. maculosus rely on cryptic dorsal colouration for protection from predators; however, resisting females are highly conspicuous as they develop orange ventro-lateral colouration, which is emphasised during rejection displays. Furthermore, flipping over may increase vulnerability to predators by decreasing a female's ability to detect predators and to flee. We tested whether females behaviourally compensate for potential increased vulnerability by altering their use of lateral threats and flip-overs under high and low perceived predation risk. The duration of flip-over rejections was significantly lower under high predation but there was no effect of predation risk on the frequency or duration of lateral threats. This suggests that females may compensate for reduced mobility or ability to detect predators rather than increased conspicuousness. Our study confirms that females are able to modulate resistance behaviour in relation to predation risk, potentially altering the trade-off between mating costs and costs of resistance.