Differences in the Songs of Birds from Island and Mainland Populations

Abstract

Based on recordings, the time-frequency characteristics and repertoire size of the advertising song were studied comparatively in several leaf warblers (Phylloscopus) and reed warblers (Acrocephalus) from mainland and island populations. No significant variations in repertoire size were found between mainland and island populations, but clear differences were revealed in the frequency and time parameters of the song between the Sakhalin and continental populations. In all of the species studied, the differences are displayed in a similar way. In the Sakhalin population, the frequency range is wider than in the mainland. Possible reasons for this expansion are discussed: (1) the impoverishment of the species composition of ornithocomplexes, (2) the effect of high air humidity, and (3) the effect of specific characteristics of the vegetation cover.