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.

Methods
This dataset contains data from three studies which together give an integrated perspective on wild zebra finch communication distance. The data was collected in UNSW Fowlers Gap Arid Zone Research Station in New South Wales, Australia, home to a well-studied population of wild zebra finches.

The three parts are:

a) Calibrated recordings of wild zebra finch songs and distance calls, conducted in 2018. This dataset contains root mean square measurements of the loudest 125 ms of zebra finch song motifs and (male and female) distance calls.

b) A transmission experiment of zebra finch song and distance calls in the natural environment, conducted in 2018. This dataset contains root mean square measurements of the loudest 125 ms of transmitted zebra finch song and distance calls (broadcasted at average natural amplitude as determined in part a), which were bandpass filtered based on bird hearing and compared with zebra finch hearing curves. The vocalisations were re-recorded at 1, 2, 4, 8, 16, 32, 64, 128 and 256 m in several different transects that represent a range of zebra finch habitats in our study site (from quite barren to relatively shrubby). We also included the Matlab script (on linked Zenodo) that we used to analyse our recordings which can be relatively easily adapted to analyse one's own transmission experiment in the same way.

c) Observational transects during which zebra finch group size and song presence was scored, conducted in 2018 and 2019. This dataset contains annotated gps points, which we used to give ecological context to the previous two parts (a and b).

For further details on how the data was collected, we refer to the (open access) related article.