Made available in DSpace on 2014-12-17T15:36:53Z (GMT). No. of bitstreams: 1 LiisaH.pdf: 524666 bytes, checksum: 8ed111d1e268e386d58d4e05b903d400 (MD5) Previous issue date: 2009-09-12 / Studies indicate that spinner dolphins use the Ba?a dos Golfinhos, in Fernando de Noronha Archipelago, for resting, reproduction, parental care and protection against shark attacks. The present study had the purpose of verifying the seasonality of spinner dolphin newborns and calves in relation to the months of the year and the pluviometric seasons (dry and rainy), as well as their interaction with the number and gender of accompanying adults and their positioning in relation to the adults (vertical, horizontal, and depth) in the above mentioned bay. The analysis were made out of photo records of dolphins collected between 2000 and 2006 (seasonality) and between 1995 and 2006 (interaction) both using ad libitum sampling method during free dives. To determine the age category, the reason between the smaller dolphin s total body length and the bigger dolphin s total body length was calculated. The dolphins were then divided into three age groups: adults, newborns and calves. Those with total body length ≥ 170cm were considered adults, newborns up to 105cm, and calves from 106cm to 128cm. In addition, the secondary characters described in literature were used to identify newborns and calves. The adults had dimensions of total lenght ≥170cm , the newborns until 105cm and calves between 106cm and 128cm. I addition, secondary characteristics described in the literature were used to indentify newborns and calves. The number of spinner dolphin newborns was greater in the month of April and higher during the rainy season. Throughout the months and pluviometric seasons (pluviometer/pluvial metric), the number of calves did not have a significant difference. Concerning to the presence of newborns and calves age groups at Ba?a dos Golfinhos, there was not a significant difference. It was possible to identify the gender of the escorting adults as (42), 95.24% being females and 4.76% males. Newborns were more frequently seen in the company of two adults, whereas calves were more often accompanied by more than two adults However, there was not a significant difference for the newborns, whereas for the calves there was a significant difference for those classified as loners and those accompanied by more than two adults. When in vertical positioning, the newborns and calves were more frequently observed in inferior position with some difference demonstrated between some of that. While in horizontal positioning both age groups were more often seen in posterior position, also with differences between them. In the depth perspective newborns and calves were positioned anterior, however with significant difference for the calves. The occurrence of a peak of newborns in the months of April may indicate the existence of a birth seasonality pattern for the beginning of the rainy season, with births scattered throughout the year. The results for the positions and escorting of newborns and calves are related to protection and suckling. These conditions reinforce the importance of the area when it comes to the care for offspring, which calls for the creation of conservation rules to the area, especially during those months with greater occurrence of newborns / Estudos indicam que golfinhos-rotadores utilizam a Ba?a dos Golfinhos de Fernando de Noronha para descanso, cuidado parental, acasalamentos e prote??o contra tubar?es. O presente estudo objetivou verificar a sazonalidade de ocorr?ncia de rec?m-nascidos e filhotes de golfinhos-rotadores durante os meses do ano e esta??es pluviom?tricas (seca e chuvosa), e a intera??o destes quanto ? quantidade e sexo de adultos acompanhantes, posicionamento dos rec?m-nascidos e filhotes em rela??o aos adultos (entre as dimen??es vertical, horizontal e profundidade) na referida enseada. As an?lises foram desenvolvidas a partir de registros fotogr?ficos dos golfinhos coletados entre 2000 e 2006 (sazonalidade) e entre 1995 e 2006 (intera??o), ambos atrav?s de amostragem ad libitum em mergulhos livres. Para a determina??o das faixas et?rias, calculou-se a raz?o entre o comprimento total do golfinho menor pelo maior mais pr?ximo a ele na mesma fotografia. Os golfinhos foram divididos em tr?s classes et?rias: adultos, rec?m-nascidos e filhotes. Indiv?duos adultos apresentavam propor??es de comprimento total ≥170cm, rec?m-nascidos at? 105cm e filhotes entre 106cm e 128cm. Em adi??o, foram utilizados caracteres secund?rios descritos na literatura para identificar rec?m-nascidos e filhotes. O maior n?mero de rec?m-nascidos foi registrado no m?s de abril e maior na esta??o chuvosa. Em rela??o ao n?mero de filhotes, n?o houve diferen?a significativa ao longo dos meses e nas esta??es pluviom?tricas. N?o houve diferen?a significatica com rela??o faixas et?rias de rec?m-nascidos e filhotes presentes na Ba?a dos Golfinhos. Entre os adultos acompanhando rec?m-nascidos e filhotes, no caso em que foi poss?vel identificar o sexo dos indiv?duos (42), 95,24% eram f?meas e 4,76% machos. Os rec?m-nascidos estavam em companhia mais freq?ente de 2 adultos, e os filhotes com mais de 2 adultos. Por?m, n?o foi registrada diferen?a para os rec?m-nascidos, ao contr?rio dos filhotes, que diferiram significativamente entre estar sozinho e os demais acompanhamentos. Com rela??o aos posisionamentos nas tr?s dimen??es analisadas, para o posicionamento vertical os rec?m-nascidos e filhotes estavam mais na posi??o inferior, demonstrando diferen?as entre algumas delas. Para a posi??o horizontal, os rec?m-nascidos e filhotes encontravam-se mais posterior, tamb?m com diferen?as entre elas. Com rela??o ? perspectiva profundidade, rec?m-nascidos e filhotes estavam posicionados na frente, por?m apresentou-se diferen?a significativa somente para os filhotes entre as demais. A presen?a do pico de ocorr?ncia de rec?m-nascidos no m?s de abril pode indicar a exist?ncia de um padr?o sazonal de nascimento no in?cio da esta??o das chuvas, por?m tamb?m com a exist?ncia de nascimentos difusos no decorrer do ano. As posi??es e acompanhamentos dos rec?m-nascidos e filhotes se relacionam ? prote??o e amamenta??o. Essas condi??es refor?am a import?ncia da ?rea para o cuidado da prole, necessitando de regras de acesso ? ?rea, principalmente durante os meses com maior ocorr?ncia de rec?m-nascidos