Long-term persistence of song performance rules in nightingales (Luscinia megarhynchos): a longitudinal field study on repertoire size and composition

Abstract

AbstractCommon nightingales (Luscinia megarhynchos) are among those bird species that possess an extremely large repertoire and perform it in a versatile singing style. Thereby, repertoire size, composition, and performance differs considerably among individuals. In this longitudinal field study, we investigated the long-term stability of these differences in the song characteristics of free-ranging nightingales. We determined the repertoire characteristics for nine adult male individuals in two successive years (three of these individuals were investigated over the course of three years) and compared these to similar measurements obtained from comparisons of song samples of different birds. Comparisons revealed remarkable differences among males, but we did not find systematic differences in the song performance of birds in successive years. Instead, song characteristics were remarkably stable within successive years. The long-term persistence of individual song characteristics suggests that they are not related to dynamically changing individual attributes, but may reflect long-term storage of information during song acquisition as juveniles. In addition, we found that the repertoire performance of adult nightingales allows fine-tuned vocal interactions among several neighbouring males.