How a simple and stereotyped acoustic signal transmits individual information: the song of the White-browed Warbler Basileuterus leucoblepharus

Abstract

The White-browed Warbler Basileuterus leucoblepharus, a common bird of the BrazilianAtlantic forest, emits only one distinct song type in the context of territorial defense. Individual or neighbor-stranger recognition may be more difficult when birds share similar songs. In fact, the analysis of songs of different individuals reveals slight differences in the temporal and the frequency domains. Effectively, a careful examination of the signals of different individuals (21) by 5 complementary methods of analysis reveals first, that one or two gaps in frequency occur between two successive notes at different moments of the song, and second, that their temporal and frequency positions are stereotyped for each individual. Playback experiments confirm these findings. By propagation experiments, we show that this individual information can be only transmitted at short range (< 100 m) in the forest. In regard to the size and the repartition of territories, this communication process appears efficient and adaptive.

Differences in Frequency of Shared Song Types Enables Neighbour‐Stranger Discrimination in a Songbird Species with Small Song Repertoire

“…Similar to the outcome of the cited study of white‐throated sparrows (Brooks & Falls ), Aubin et al. () showed experimentally that the strength of the response to the modified neighbour song of the white‐browed warbler ( Basileuterus lecoblepharus ) increases with only relatively small shifts in time or frequency of a very simple song (compare also Mathevon et al. ).…”

Large vocal repertoires do not constrain the dear enemy effect: a playback experiment and comparative study of songbirds

“…We excluded studies that used altered song types of neighbours to imitate strangers (e.g. Aubin, Mathevon, Da Silva, Vielliard, & Sebe, 2004;Osiejuk, 2014) because these experiments do not directly test neighbourestranger discrimination but rather what elements of a song are used for individual discrimination. We chose to focus on songbirds because they have received extensive study, because song repertoires are common (MacDougallShackleton, 1997), and because there have been numerous experiments on neighbourestranger discrimination in these animals (Stoddard, 1996).…”

Efficiency of playback for assessing the occurrence of five bird species in Brazilian Atlantic Forest fragments

“…According to Schieck (1997) vocalizations with frequencies higher than 2 kHz may suffer strong attenuation in the forest. Aubin et al (2002Aubin et al ( , 2004 stated that the song of B. leucoblepharus is particularly high-pitched and susceptible to a strong attenuation when propagating through dense vegetation. In those cases, playback will be effi cient to identify only close birds, since the playback can only reach nearby individuals.…”