Defining the active space of cane toad (Rhinella marina) advertisement calls: males respond from further than females

Many animals produce advertisement vocalisations to attract mates. A vocalisation's active space is the area within which a receiver responds to it, while its maximum extent occurs when a receiver stops responding. We mapped behavioural responses of male and female cane toads (Rhinella marina) to advertisement calls, by conducting experimental playbacks to: (i) examine attenuation of a cane toad call, (ii) define the active space of these vocalisations, by measuring phonotaxis at different distances from the call, and (iii) quantify the active space of calls for both sexes, separately. The call was fully attenuated 120-130 m from its source. Both sexes displayed positive phonotaxis 20-70 m from calls. Males also displayed positive phonotaxis 70-120 m from calls, whereas females' movement preferences were random >70 m from a call. Differences between male and female responses were likely driven by differences in their use of information provided by calls.