Doi: https://doi.org/10.13157/arla.71.2.2024.ra1
Authors: Irina MAROVA, Vladislav ANTIPOV and Vladimir IVANITSKII
E-mail: vladivanit@yandex.ru
Published: Volume 71.2, July 2024. Pages 229-245.
Language: English
Keywords: avian song, weather affect and wintering ground exchange
Summary:
Between 2010 and 2019, we studied the variations in the singing of the Thrush Nightingale in the city of Moscow and compared song characteristics with those in the Tula region (180-200km south of Moscow). The singing of the nightingales in Moscow changed dramatically between 2011 and 2014. Certain song types widely used in 2010 and 2011 became very rare or disappeared completely in 2014. The song types previously found in the tula region appeared in the Moscow region in significant numbers. The song types new to the Moscow region were sung in the same order as the same song types were sung in the Tula region. The acoustic parameters of elements within song types shared by Moscow and Tula nightingales shifted in the Moscow songs between 2011 and 2014, becoming more similar to those of the Tula songs recorded in 2012. We propose two hypotheses explaining these changes. The first is that new song types, syntactic models and time-frequency characteristics were introduced into the Moscow population by Tula birds, either from birds immigrating from Tula to Moscow or by the exchange of vocal models between individuals from these two populations on a common wintering ground. The second possibility is that vocal models were introduced from another source into the Moscow and Tula populations simultaneously and independently of each other. Both possibilities seem plausible since: 1) high immigration rates have been described in other populations in years with unusually warm weather in spring, which could explain both thesimultaneous “arrival” of changes to the Moscow and Tula populations or the arrival of Tula birds with a different song dialect to Moscow. 2) Moreover, as Thrush Nightingale populations share a lot of song types and syntactic models, joint wintering of individuals from these populations looks quite possible. However, comparing the performed song repertoires between the two populations in different years, the most likely possibility seems to be that the change occurred simultaneously in the two populations.
