Repertório vocal e variações no canto de aves em diferentes áreas florestais no cerrado sensu lato

Abstract

The sound communication is the exchange of information between a issuing and a receiver individuals and is through audible signals. Its structure and organization are determined by evolution and adaptive pressures imposed on each species. During the learning process many factors can cause variations in their repertoires. These factors can be natural or anthropic, as in the case of high noise levels in areas near of the cities that impose challenges for sound communication of birds. Many species of birds have the ability to adjust their sound signals to high levels of noise by increasing the frequency of the signals and making shorter sounds and with less notes. The aims of this work were characterize the vocal repertoire of bird species, check for differences in acoustic parameters of vocalizations of these species between near and far forest areas from urban areas, check for differences in noise level between the forest areas, and determine which species of birds have potential to be used in biomonitoring. Recordings were made between july/2013 and november/2014 in four forest areas of Triangulo Mineiro, MG, two (Glória and São José) near of urban areas (loud noise) and two (Água Fria and Galheiro) far (low noise). The parameters analyzed were dominant frequency, song duration and number of notes for each of the 6,220 vocalizations of the ten species studied. A. galeata had the highest repertoire and T. sulphurescens the lowest. C. gujanensis and H. longirostris were the only species that had more than one type of song. A. galeata, B. culicivorus, C. leucotis, C. gujanensis, H. longirostris, L. amaurocephalus, P. albosquamatus, T. sulphurescens and V. passerinus had higher dominant frequency in areas near of urban areas. A. galeata, B. culicivorus, H. longirostris and M. flaveola presented in these areas songs with shorter duration and H. longirostris and M. flaveola had fewer notes. Near forest areas from urban areas have higher noise level than far forest areas. All species can be used in monitoring, as presented variations in at least one parameter analyzed and all parameters analyzed were sensitive to high levels of noise. Antilophia galeata e H. longirostris are the most suitable for use in biomonitoring of forest Cerrado areas, it showed considerable variations in the acoustic parameters and are found in areas of different sizes, degree of disturbance and noise levels.