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| Erber,Claudia; Simão,Sheila M.. |
| From July 2001 to June 2002, we recorded a total of 2h55min of Tucuxi Dolphin Sotalia fluviatilis vocalizations from Sepetiba Bay, Brazil (22º35'S-44º03'W). A total of 3350 whistles were analyzed quantitative and qualitatively and were divided into 124 types, by visual inspection of sonograms. The following parameters were measured: Initial Frequency, Final Frequency, Minimum Frequency, Maximum Frequency, Duration, Number of Inflections, Frequency at the Inflection Points, Frequency at 1/2, 1/4, and 3/4 of whistle duration, Presence of Frequency Modulation and Harmonics. Ascending type whistles (N=2719) were most common, representing 82% of the total. Dolphin behavior and average group size observed during recording influenced the whistle's quantitative... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sotalia fluviatilis; Cetacea; Delphinidea; Vocal repertoire; Whistles; Behavior. |
| Ano: 2004 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652004000200029 |
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| Tardin,Rodrigo H.; Pinto,Míriam P.; Alves,Maria Alice S.; Simão,Sheila M.. |
| Difficulties in quantifying behavioral events can cause loss of information about cetacean behavior, especially behaviors whose functions are still debated. The lack of knowledge is greater for South American species such as Sotalia guianensis (Van Benédén, 1864). Our objective was to contextualize the behavioral events inside behavioral states using a Permutational Multivariate Analysis of Variance (MANOVA). Three events occurred in the Feeding, Socio-Sexual and Travelling states (Porpoising, Side flop, Tail out dive), and five events occurred in the Feeding and Travelling states (Back flop, Horizontal jump, Lobtail, Spy-hop, Partial flop ahead). Three events (Belly exposure, Club, and Heading) occurred exclusively in the Socio-sexual state. Partial Back... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Aerial behavior; Behavioral analysis; Guiana dolphin; Surface behavior. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702014000100001 |
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| Lodi,Liliane; Tardin,Rodrigo H.; Hetzel,Bia; Maciel,Israel S.; Figueiredo,Luciana D.; Simão,Sheila M.. |
| Bryde's whales, Balaenoptera edeni Anderson, 1879, were observed on 17 occasions (N = 21 surveys) in the coastal waters off Rio de Janeiro in southeastern Brazil during austral summer through autumn 2014. Five whales were individually identified using photo-identification techniques. The mean interval between resightings for all individuals was 12.8 days, with a minimum of one day and a maximum of 48 days. The comparison between the catalogs of Bryde's whales off Rio de Janeiro and the Cabo Frio region revealed matches for three individuals. The resightings show movements of up to 149.6 km along the coastal waters off the state of Rio de Janeiro. Most of the observations consisted of solitary individuals (82.3% of sightings). Feeding was the predominant... |
| Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Balaenoptera edeni; Displacements; Individual identification; Surface activities. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702015000200171 |
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| Oliveira,Elaine C. da S.; Tardin,Rodrigo H.; Poletto,Fabiana R.; Simão,Sheila M.. |
| The coordinated feeding tactics used by delphinids are influenced by differences in the distribution of prey species, season, and opportunities for social learning. In the present study, we compared the coordinated feeding behavior of two populations of the Guiana dolphin, Sotalia guianensis, in southeastern Brazil, and how these feeding tactics vary seasonality and in the presence of calves. We observed eight types of coordinated feeding tactics, which differed in frequency and in the mean number of individuals engaged in them, and between both areas. Feeding tactics used to herd and capture prey were the most frequent and engaged a greater number of individuals, suggesting that these tactics are better for capturing fish that gather in larger schools.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cetaceans; Coordinated hunt; Feeding tactics; Prey; Social behavior. |
| Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702013000600001 |
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| Tardin,Rodrigo H. O.; Especie,Mariana A.; Nery,Mariana F.; D'Azeredo,Felipe T.; Simão,Sheila M.. |
| Differences in distribution, prey species, season and social learning opportunities influence the feeding tactics used by marine mammals. Here, we analyze the coordinated feeding behavior of the Guiana dolphin, Sotalia guianensis (Van Bénéden, 1864, Delphinidae) and its relation to seasonality and the presence of calves. In a total of 201 feeding bouts, we observed four types of coordinated feeding tactics, which differed in frequency and in mean number of engaged individuals. Tactics in which dolphins used their bodies to herd and capture prey were the most frequent, presenting a higher frequency and engaging a higher number of individuals, suggesting that these tactics are better for capturing fishes which form larger schools. Furthermore, the seasons... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Behavioral flexibility; Feeding repertoire; Social foraging; Social learning. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000300002 |
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| Nery,Mariana F.; Espécie,Mariana de A.; Simão,Sheila M.. |
| Estuarine dolphins, Sotalia guianensis (Van Bénéden, 1864), were identified in Sepetiba Bay (22º35'S, 44º03'W), state of Rio de Janeiro, Brazil, between February 1994 and July 2006 using the photo-identification method. A total of 72 surveys resulted in the identification and cataloguing of 217 individual dolphins. Seventy-nine (36%) were resighted at least once during the study period. The average interval between resightings was 40,6 ± 31,1 months. Large numbers of mother-and-calf pairs were recorded during the 12 years and new individuals were frequently encountered in the photographic records. These results suggest that part of the dolphin population is more consistently found in Sepetiba Bay, probably for feeding and reproduction, while other... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Estuarine dolphin; Habitat use; Photo-identification. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752008000200004 |
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