Element repertoire: change and development with age in Whitethroat Sylvia communis song

Journal of Ornithology 04/2010; 151(2):469-476. DOI: 10.1007/s10336-009-0481-4

ABSTRACT Song repertoires are often important determining factors in sexual selection. In several species, older males have larger
repertoires than 1-year-old males. The development of large song repertoires by an individual is, however, poorly understood.
We studied song element repertoire changes in five individual male Whitethroats Sylvia communis sampled as 1- and 2-year olds. These males increased the size of their element repertoire between their first and second
year, but song length and number of different elements per song did not change. On average, 44.3% of the song elements in
the first-year repertoire were also found in the second-year repertoire. Elements shared between years were found earlier
in the songs and tended to occur in sequences. Sequences of shared elements also seemed to be conserved between years. The
study suggests that the song element repertoire of the second year is partly based on the first-year repertoire, which may
explain why large song repertoires are mainly expressed by males at least 2 years of age. It would appear, therefore, that
song element repertoire size could be a reliable signal of male age.

KeywordsAge-Delayed maturation-Song development-Song repertoire-
Sylvia communis

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