Multivariate statistical analysis of songs of the male Common Blackbird (Turdus merula): an example from western Victoria, Australia

Abstract

Variation in the song of the male Common Blackbird was investigated within and between two locations in 10 western Victoria. Each of 400 phrases (100 phrases per male) was characterised by 61 measurements relating to 13 aspects of each phrase. Principle component and stepwise discriminant analyses were undertaken on these measurements. Classification of blackbird song for location and individuality was based on timing within the phrase of the loudest elements. Evidence was found for within-phrase variability, with the greatest variation in the middle of the phrase. Within-and between-site comparison found that blackbird song exhibited both individual and site-specific characteristics consistent with earlier suggestions of phrase sharing within local populations. The study demonstrated that an objective statistical approach to song analysis was able to discriminant between individual birds from different locations.