The ‘Push-Up’ as a Calling Posture in Nectophrynoides tornieri (Anura: Bufonidae) in the Amani Nature Reserve, Tanzania

Abstract

Abstract Males of Tornier's Forest Toad, Nectophrynoides tornieri, were observed to perform a peculiar display posture, the ‘push-up’: the males raised themselves from a substrate (always a plant structure) by first stretching their fore legs into a ‘sit-up’ and then their hind legs to assume the position. We examined possible functions for the push-up position in manipulative behavioral experiments. In a majority of the tested males, the introduction of a conspecific male only evoked the less conspicuous sit-up display, whereas a playback of male vocalization more often triggered the full push-up position, usually followed by a vocal response. We found no association between the sit-up and the push-up display and the presence of a female N. tornieri near a male's calling perch. Our findings support the hypothesis that the push-up posture is a display in response to other calling males; whilst being the usual calling posture, it might also be important in visual communication. We describe in detail the ch...