Song Dialect of Oriental Magpie-robin (Copsychus saularis) in Northern Thailand

Abstract

Different song types were recorded from 60 males of Oriental Magpie-robin, Copsychus saularis Linnaeus, 1758. The survey was carried out in the provinces of Phayao and Chiang Mai, northern Thailand from April 2000 to March 2001. Spectrogram study revealed that all song types shared some common features: The song frequency ranged from 2 to 6 kHz; each completed song composed of 2 or more strophes (2-112) repetitively used; the core elements occurred within the first second of each strophe. Core element is a compartment that shared among all individuals of this species. These three characters are here recognized and considered as species recognition for the Oriental Magpie-robin. Variation of song syntaxes at the marking elements, the last element of core element groups, were found among male populations recorded from different study areas and is regarded as song dialect. Different pattern of the specific elements were presented at the terminal part of each strophe and can be considered individual variation within populations. Geographical division and learning behaviors are likely to cause differences among specific elements, leading to significant trend of song dialect of this species.