PADRÃO DE VARIAÇÃO SAZONAL E MULTINÍVEL NO CANTO DE ANÚNCIO DE SCINAX FUSCOMARGINATUS (LUTZ, 1925), BRASIL CENTRAL

Abstract

In the first chapter of this dissertation, we (I include coauthors) used the Automated Digital Record (ADR) method to record the vocalization activity of S. fuscomarginatus males between November 2013 and October 2014 in the southwest of the Goiás state, Central Brazil. We analyzed a total of 43.2 h, and obtained the air temperature and rainfall in meteorologic station. Registers by ADR showed that calling episodes of Scinax fuscomarginatus males occur along the night, with the peak of vocalization between 18:00 and 00:00 h. ADR detected vocalization activity in August 2014, however the local rainy season typically occurs from October to March. Thus, we argue that ADR is a potential method for implementing conservation initiatives in related species and useful for providing information on the natural history of anuran species. In addition, our results indicate temperature as one of the factors related to vocalization activity. In the second chapter, we recorded the advertisement call from 2008 to 2016 in twelve municipalities in the state of Goiás, Brazil. We analyzed 655 advertisement call of 131 males of S. fuscomarginatus. The advertisement call exhibited the structure with a note composed by multiple pulses, in which the acoustic properties analyzed are predominantly stereotyped at the individual level. Nevertheless, the analyzed acoustic properties are potentially involved in the discrimination process between males (CVa / CVw> 1), mainly minimum frequency, maximum frequency and singing duration. In this case, we do not contradict the idea that individual discrimination is mediated by a subset of acoustic properties, since the dominant frequency and the pulse rate (not measured in the present study) were relevant in other descriptions of Scinax fuscomarginatus’ advertisement call. Such results indicate that a subset of acoustic properties is involved in discrimination, when we compared with previous studies. Finally, the patterns of advertisement call variation at the population level involve temporal and spectral properties, suggesting that species with many stereotyped acoustic properties tend to provide relevant evidence on acoustic variation at different organization levels.