Characterization of sound emissions of humpback whales, Megaptera novaeangliae (Borowski, 1781) in the Abrolhos region from 2005 to 2016

Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2021-09-27T13:49:40Z No. of bitstreams: 1 2019 - Eduardo Cabral Casado Lima.pdf: 3870911 bytes, checksum: 82a1443b37b3eb3b4fcafbf29db897a1 (MD5) Made available in DSpace on 2021-09-27T13:49:40Z (GMT). No. of bitstreams: 1 2019 - Eduardo Cabral Casado Lima.pdf: 3870911 bytes, checksum: 82a1443b37b3eb3b4fcafbf29db897a1 (MD5) Previous issue date: 2019-02-22 CAPES - Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior The objective of this study was to analyze the variation of the structure of the humpback whale song (Megaptera novaeangliae) in the Abrolhos Bank Region during the period from 2005 to 2016, describing the hierarchical level of Phrases and Themes throughout this period. Humpback whale sound recordings were conducted by the Baleia Jubarte Institute (IBJ) team from 2005 to 2016, in the Abrolhos region, Bahia, Brazil. The reading of the hierarchical level of Phrases and Themes was carried out from the Raven 1.5 software, with five parameters being evaluated: (1) Lowest Frequency (Hz); (2) Higher frequency (Hz); (3) Frequency delta (Hz); (4) Peak Frequency (Hz); (5) Delta duration (s). The mean, standard deviation (Dp), minimum value (Vmin) and maximum value (Vmax) of each parameter in each sentence were calculated. Student's t-test, applied in the Phrases that occurred in two years and analysis of variances (ANOVA) and the Tukey test applied in the Phrases that occurred in three years were carried out to verify if there were significant variations between the years of study. At the hierarchical level of Themes, the units that composed the phrases with the best visualization for analysis of the measurement of two parameters measured in Raven 1.5 software were selected: (1) Peak frequency (Hz) and (2) duration of time (s). We analyzed 6 hours, 07 minutes and 04 seconds with a 9-year scope for the study, being only the year 2010, presenting many noises in the samples, therefore not used in the analyzes. The results show a number of 16 Phrases and 13 Themes over the years of study. It is evidenced, therefore, that the song of the humpback whale is quite variable in relation to its structures, Units, Phrases and Themes, not presenting a fixed pattern in its song. Phrases and Themes that were found in this work, were also found around the world. An example is theme 5, composed of the phrase 6, which in 2006 is very similar to that found in Madagascar the same year. This fact may suggest that there is a transmission of learning in the feeding areas which may be occurring in the Antarctic food area. The monitoring over the years will allow us to evaluate the changes that occur in the reproductive seasons, helping to understand the evolution of the Themes and Phrases, reinforcing the idea that there may be similarities between them with populations from other places around the world. O estudo teve como objetivo geral analisar a varia??o da estrutura da can??o de baleia jubarte (Megaptera novaeangliae) na Regi?o do Banco de Abrolhos, durante o per?odo de 2005 a 2016, descrevendo o n?vel hier?rquico de Frases e Temas ao longo desse per?odo. Os registros das emiss?es sonoras de baleia jubarte foram realizados pela equipe do Instituto Baleia Jubarte (IBJ) de 2005 a 2016, na regi?o de Abrolhos, Bahia, Brasil. Foi realizada a leitura do n?vel hier?rquico de Frases e Temas, a partir do software Raven 1.5, avaliando-se para Frases cinco par?metros: (1) Menor Frequ?ncia (Hz); (2) Maior frequ?ncia (Hz); (3) Delta da frequ?ncia (Hz); (4) Frequ?ncia Pico (Hz); (5) Delta da dura??o (s). Foram calculados, a m?dia, o desvio padr?o (Dp), o valor m?nimo (Vmin) e o valor m?ximo (Vmax) de cada par?metro em cada Frase. Foram realizados o teste t-Student, aplicado nas Frases que ocorreram em dois anos e an?lises de vari?ncias (ANOVA) e o teste de Tukey aplicados nas Frases que ocorreram em tr?s anos para verificar se ocorreram varia??es significativas entre os anos de estudo. No n?vel hier?rquico de Temas, foram selecionadas as Unidades que compunham as Frases com melhor visualiza??o para an?lise da medi??o de dois par?metros medidos no software Raven 1.5: (1) Frequ?ncia Pico (Hz) e (2)dura??o do tempo(s). Foram analisadas 6 horas, 07 minutos e 04 segundos com abrang?ncia de 9 anos para o estudo, sendo, apenas o ano de 2010, apresentando muitos ru?dos nas amostras, portanto n?o utilizado nas an?lises. Os resultados mostram uma quantidade de 16 frases e 13 temas ao longo dos anos de estudo. ? evidenciado, portanto, que a can??o da baleia jubarte ? bastante vari?vel em rela??o ?s suas estruturas, Unidades, Frases e Temas, n?o apresentando um padr?o fixo em seu canto. Frases e Temas que foram encontrados no presente trabalho, tamb?m foram encontrados ao redor do mundo. Um exemplo ? o tema 5, composto pela frase 6, que em 2006 ? muito similar ao encontrado em Madagascar no mesmo ano. Esse fato pode sugerir que haja uma transmiss?o de aprendizagem nas ?reas de alimenta??o o que pode estar ocorrendo na ?rea de alimenta??o na Ant?rtica. O acompanhamento ao longo dos anos vai permitir avaliar as mudan?as que ocorrem nas esta??es reprodutivas, auxiliando no entendimento da evolu??o dos Temas e Frases, refor?ando a ideia de que possa existir semelhan?as entre eles com popula??es de outros lugares ao redor do mundo.