Function of the Song and Song Repertoire in the European Starling (Sturnus Vulgaris) : an Aviary Experiment

Abstract

We confronted individually-caged male European starlings, Sturnus vulgaris, with conspecifics of both sexes in order to study singing behaviour during intrasexual and intersexual encounters. Males spent more time at the nestbox, sang more songs and more song types during female presentations than during control periods (observation periods with no conspecifics). Males also sang more songs in the nestbox and flew more to the nestbox with green nest material. During male presentations, only the time spent at the nestbox and the carrying of nest material increased significantly. Males spent more time at the nestbox, sang more songs and more song types in response to a female stimulus than to a male stimulus. Males also sang more songs in the nestbox and flew more to the nestbox with nest material during female than during male presentations. These results suggest that the song and song repertoire of male starlings serve primarily an intersexual rather than an intrasexual function. However, in contrast to a previous study, our results suggest that singing also serves as an intrasexual signal to deter rivals at close encounter. We also tested the hypothesis that the 'whistles' and the 'warbling song' have separate intrasexual and intersexual functions, as has been suggested in the literature. We found no evidence for a specialized intrasexual function of the whistles nor for a specialized intersexual function of the warbling song. From this study it also appears that variations in the size of the aviary can modify the behavioural responses of starling males. New information with regard to the use of green nest material by male starlings is given.

Social Modulation of Sequence and Syllable Variability in Adult Birdsong

“…Songs produced in the presence of a female have been found to be significantly longer than those produced in isolation (Eens 1993;Kao and Brainard 2006;Sossinka and Böhner 1980). However, we did not find a significant difference in song length (exclusive of introductory notes) between UD and FD songs in the Bengalese finch (paired t-test: t 18 ϭ 0.86, P ϭ 0.3996).…”

“…Context-dependent modulations of song unrelated to variability have also been noted in other songbirds (Cooper and Goller 2006;Eens 1993;Kao and Brainard 2006;Sossinka and Böhner 1980). Therefore, we examined changes to three other song features-the number of introductory notes, song length, and song tempo.…”

Green nesting material has a function in mate attraction in the European starling

“…Instead it has been suggested that starlings use green material for mate attraction or pair bonding Fauth et al 1991;Gwinner 1997;Komdeur et al 2002). Until now, there has been no experimental support from the field for the courtship or the male quality hypotheses Fauth et al 1991;Eens et al 1993;Pinxten et al 1995;Gwinner 1997;Komdeur et al 2002).…”

Lesions to the medial preoptic nucleus differentially affect singing and nest box-directed behaviors within and outside of the breeding season in European starlings (Sturnus vulgaris).

“…Females preferentially approach nest boxes broadcasting conspecific song compared to no song and are more likely to enter nest boxes broadcasting complex song compared to simple song (Mountjoy & Lemon, 1991). After pairing, males reduce song production, generally restricting periods of singing to immediately prior to copulation (Eens, Pinxten, & Verheyen, 1990;Eens, Pinxten, & Verheyen, 1993;Eens, Pinxten, & Verheyen, 1994) or to periods when the mate is absent (Cuthill & Hindmarsh, 1985). Additionally, males with nest boxes in spring have been found to respond to intruding males by flying to the nest site and singing, but not gathering nest material or wing waving (Eens et al, 1990;Eens et al, 1993).…”

“…After pairing, males reduce song production, generally restricting periods of singing to immediately prior to copulation (Eens, Pinxten, & Verheyen, 1990;Eens, Pinxten, & Verheyen, 1993;Eens, Pinxten, & Verheyen, 1994) or to periods when the mate is absent (Cuthill & Hindmarsh, 1985). Additionally, males with nest boxes in spring have been found to respond to intruding males by flying to the nest site and singing, but not gathering nest material or wing waving (Eens et al, 1990;Eens et al, 1993). Fighting between two males in a nest hole may be accompanied by singing (Eens, 1997), and males tend to avoid nest boxes broadcasting complex male starling song (Mountjoy & Lemon, 1991).…”