The effects of duet coordination on territory defence in an Australian arid zone passerine

Duetting, a cooperative vocal behaviour performed by mated pairs, is a distinctive behaviour among many species in specifically primates and birds. Duetting behaviour is most seen in tropical birds and is often studied in a territorial context. However, we still know little about what elements of duets make them a stronger territorial signal. One hypothesis is that the level of duet coordination can indicate the degree of threat posed to a rival pair. Only a few studies have investigated this, and mixed results have been found. To further address the implications of duetting precision in a territorial context, we determined to what extend the duetting behaviour in the chirruping wedgebill (Psophodes cristatus), a bird that is found in the arid regions of the Australian outback, predicts - and is affected by - the level of duet coordination. We tested this with playback experiments where we broadcast coordinated and uncoordinated duets at mated pairs, predicting that pairs would exhibit stronger responses to coordinated duets than to uncoordinated ones and sing more coordinately after the simulated intrusion than before. Our results provide further insights into the role of fine vocal coordination and contributes to the broader understanding of cooperative vocal behaviours in the context of territory defence

Zebra finch song and distance call amplitude measurements: A transmission experiment and observational transects in the natural environment

Birdsong is typically seen as a long-range signal functioning in mate attraction and territory defense. Among birds, the zebra finch is the prime model organism in bioacoustics, yet almost exclusively studied in the lab. In the wild, however, zebra finch song differs strikingly from songbirds commonly studied in the wild as zebra finch males sing most after mating and in the absence of territoriality. Using data from the wild, we here provide an ecological context for a wealth of laboratory studies. By integrating calibrated sound recordings, sound transmission experiments and social ecology of zebra finches in the wild with insights from hearing physiology we show that wild zebra finch song is a very short-range signal with an audible range of about nine meters and that even the louder distance calls do not carry much farther (up to about fourteen meters). These integrated findings provide an ecological context for the interpretation of laboratory studies of this species and indicate that the vocal communication distance of the main laboratory species for avian acoustics contrasts strikingly with songbirds that use their song as a long-range advertisement signal

Zebra finch song is a very short-range signal in the wild : evidence from an integrated approach

Birdsong is typically seen as a long-range signal functioning in mate attraction and territory defense. Among birds, the zebra finch is the prime model organism in bioacoustics, yet almost exclusively studied in the lab. In the wild, however, zebra finch song differs strikingly from songbirds commonly studied in the wild as zebra finch males sing most after mating and in the absence of territoriality. Using data from the wild, we here provide an ecological context for a wealth of laboratory studies. By integrating calibrated sound recordings, sound transmission experiments and social ecology of zebra finches in the wild with insights from hearing physiology we show that wild zebra finch song is a very short-range signal with an audible range of about nine meters and that even the louder distance calls do not carry much farther (up to about fourteen meters). These integrated findings provide an ecological context for the interpretation of laboratory studies of this species and indicate that the vocal communication distance of the main laboratory species for avian acoustics contrasts strikingly with songbirds that use their song as a long-range advertisement signal

Data for: Zebra finch song ecology: monitoring of breeding, observational transects, focal and year-round acoustic recordings, and a large-scale simultaneous playback experiment

Male songbirds sing to establish territories and to attract mates. However, increasing reports of singing in non-reproductive contexts and by females show that song use is more diverse than previously considered. Therefore, alternative functions of song, such as social cohesion and synchronisation of breeding, by and large were overlooked even in such well-studied species as the zebra finch (Taeniopygia guttata). In these social songbirds only the males sing and pairs breed synchronously in loose colonies following aseasonal rain events in their arid habitat. As males are not territorial, and pairs form long-term monogamous bonds early in life, conventional theory predicts that zebra finches should not sing much at all; yet they do and their song is the focus of hundreds of lab-based studies. We hypothesise that zebra finch song functions to maintain social cohesion and to synchronise breeding. Here we test this idea using data from five years of field studies, including observational transects, focal and year-round audio recordings, and a large-scale playback experiment. We show that zebra finches frequently sing while in groups, that breeding status influences song output at the nest and at aggregations, that they sing year-round, and that they predominantly sing when with their partner, suggesting that song remains important after pair formation. Our playback reveals that song actively features in social aggregations as it attracts conspecifics. Together, these results demonstrate that birdsong has important functions beyond territoriality and mate choice, illustrating its importance in coordination and cohesion of social units within larger societies

The social role of song in wild zebra finches

Male songbirds sing to establish territories and to attract mates.1,2 However, increasing reports of singing in non-reproductive contexts3 and by females4,5 show that song use is more diverse than previously considered. Therefore, alternative functions of song, such as social cohesion3 and synchronization of breeding, by and large, were overlooked even in such well-studied species such as the zebra finch (Taeniopygia guttata). In these social songbirds, only the males sing, and pairs breed synchronously in loose colonies,6,7 following aseasonal rain events in their arid habitat.8,9 As males are not territorial, and pairs form long-term monogamous bonds early in life, conventional theory predicts that zebra finches should not sing much at all; however, they do and their song is the focus of hundreds of lab-based studies.10,11,12,13,14,15,16,17,18,19,20,21,22 We hypothesize that zebra finch song functions to maintain social cohesion and to synchronize breeding. Here, we test this idea using data from 5 years of field studies, including observational transects, focal and year-round audio recordings, and a large-scale playback experiment. We show that zebra finches frequently sing while in groups, that breeding status influences song output at the nest and at aggregations, that they sing year round, and that they predominantly sing when with their partner, suggesting that the song remains important after pair formation. Our playback reveals that song actively features in social aggregations as it attracts conspecifics. Together, these results demonstrate that birdsong has important functions beyond territoriality and mate choice, illustrating its importance in coordination and cohesion of social units within larger societies

Hanging out in the outback: the use of social hotspots by wild zebra finches

The social and spatial organisation of avian societies is often complex and dynamic with individuals socialising with others in a local population. Although social interactions can readily be described in colonial breeders through the location of nests, social interactions regularly take place in other contexts that are often not considered. Social behaviour in the colonially breeding zebra finch, Taeniopygia guttata, has been the focus of much work in the laboratory, but very little is known about their social organisation in free‐living populations, especially outside the breeding context. Here we characterise semi‐permanent gathering locations, or ‘social hotspots' in the zebra finch in the wild. We determined the use of such social hotspots and the resulting group dynamics by quantifying movements to and from these locations through direct observation and by quantifying the vocal activity at these locations using acoustic recorders. We show that, throughout the day, zebra finches regularly visit these hotspots, and the hotspots are occupied for a substantial proportion of the day. Individuals typically arrived and left in pairs, or small groups, indicating that these social hotspots do not function just for flock formation. Instead, the high levels of vocal activity at these hotspots indicate that they may potentially function as local hubs for socialisation and information exchange, whilst also perhaps providing safety‐in‐numbers benefits to individuals during periods of resting. These findings characterise an important component of the natural social life of one of the most widely studied birds in captivity. The characterisation of these social hotspots highlights the use of landmarks by birds to facilitate social contacts, cohesion, and behaviour, in a social bird. Similar hangouts and social hotspots may be a feature of social behaviour in other multi‐level aggregative species in which the fission and fusion of groups is an important component of daily life

A Bayesian approach to luminescent down-conversion

International audienc

A Bayesian approach to luminescent down-conversion

International audienc