The role of arrival time to the breeding grounds in the song development of juvenile pied flycatchers

Abstract

Male birdsongs function as territory defence and/or mate attraction. Females may use different song characteristics in choosing a male, such as a song's complexity. Such is the case for the open-ended learning pied flycatcher (Ficedula hypoleuca), in which males are able to learn new syllables and increase their song complexity even as adults. There are many male characteristics that tend to correlate with song complexity, including arrival time (early vs. late), age of the male (juvenile vs. adult), and the plumage colour (darker-higher quality vs. duller-lower quality), but it has yet to be assessed what effect arrival time has on the song development of juvenile pied flycatchers. This study modelled how arrival time and male quality (plumage colour used as a proxy) affects song complexity, measured by repertoire size, strophe versatility, and song versatility of pied flycatchers when they were 1-year old and 2-years old. The average strophe duration, a strophe versatility parameter, was also included. Age of the pied flycatcher best explained the development of repertoire size and strophe versatility, whereas the development of song versatility was best explained by age, male quality, and arrival time. Arrival time best explained the development of strophe duration. Although it is supported that age affects song development the most, there is a trend that earlier arriving males that are of higher quality have a more complex song than late arriving, lower quality males.IV