Diversité et spécificité des chants du Bruant zizi (Emberiza cirlus)

Abstract

The diversity and specificity of the vocal repertoire of the Cirl bunting (Emberiza cirlus ) is studied, making use of 2180 song recordings of 89 individual birds from different parts of Europe. Cirl bunting songs are composed of the repetition of a single syllabe. On the average, each male repertoire is made of 2.4 song types (or syllabes). However, neighbouring conspecifics very often have different repertoires ; consequently, there is a great variety of syllabe types. Such a diversity is nevertheless limited, as syllabe types consist of a combination of smaller acoustic units, the elements, whose number is much smaller than that of the syllabes. Only five categories of elements can indeed be distinguished, and the species’ «phonology » is therefore limited. Two atypical songs were recorded in natural conditions. In the first case, the song syntax was atypical, whereas it was the shape of the elements, and the syllabe pattern, which were unusual in the second case — though the song of the latter bird was similar to that developped by a Cirl bunting reared in acoustic isolation. Acoustic imitation and social contacts between conspecifics can be considered as basic requirements f or the transmission of the specific song repertoire from one generation to the other in this species.