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Florianópolis, Brazil

Magalhaes M.S.,Federal University of Amazonas | Barsante Santos A.J.,Fundacao Pro TAMAR | da Silva N.B.,Federal University of Rio Grande do Norte | de Moura C.E.B.,Federal University of Rio Grande do Norte
Zoologia | Year: 2012

This study characterized the morphology of the digestive tube of five species of sea turtles. We used specimens found dead along the coast of the state Rio Grande do Norte, as well as specimens accidentally killed as a result of pelagic longline fishing. Nineteen animals of the following species were analyzed: Chelonia mydas (Linnaeus, 1758) (n = 9), Lepidochelys olivacea (Eschscholtz, 1829) (n = 6), Caretta caretta (Linnaeus, 1758) (n = 2), Eretmochelys imbricate (Linnaeus, 1766) (n = 1) and Dermochelys coriacea (Vandelli, 1761) (n = 1). After opening the plastron, we removed the digestive organs and described the external and internal morphology of each organ. The esophagus of all species had pointed papillae on the mucosa. The stomach varied in shape among species. Differences were found in the mucosa of the small intestine. It was reticular in the duodenum, and longitudinal rectilinear in the jejunum/ileum. In all species an alternation of saccular and narrow regions was observed in the large intestine. The exception was D. coriacea, in which the mucosa of the entire large intestine had irregularly distributed folds. The pattern of the esophagus was the same in all species. The morphology of the stomach differed among species, and these differences reflect their diets. In addition, the distribution pattern of the folds on the mucosa of the small intestine varied between regions of the intestine and among species. © 2011 Sociedade Brasileira de Zoologia. Source

Proietti M.C.,Grande Rio University | Reisser J.,University of Western Australia | Reisser J.,CSIRO | Marins L.F.,Grande Rio University | And 5 more authors.
PLoS ONE | Year: 2014

Understanding the connections between sea turtle populations is fundamental for their effective conservation. Brazil hosts important hawksbill feeding areas, but few studies have focused on how they connect with nesting populations in the Atlantic. Here, we (1) characterized mitochondrial DNA control region haplotypes of immature hawksbills feeding along the coast of Brazil (five areas ranging from equatorial to temperate latitudes, 157 skin samples), (2) analyzed genetic structure among Atlantic hawksbill feeding populations, and (3) inferred natal origins of hawksbills in Brazilian waters using genetic, oceanographic, and population size information. We report ten haplotypes for the sampled Brazilian sites, most of which were previously observed at other Atlantic feeding grounds and rookeries. Genetic profiles of Brazilian feeding areas were significantly different from those in other regions (Caribbean and Africa), and a significant structure was observed between Brazilian feeding grounds grouped into areas influenced by the South Equatorial/North Brazil Current and those influenced by the Brazil Current. Our genetic analysis estimates that the studied Brazilian feeding aggregations are mostly composed of animals originating from the domestic rookeries Bahia and Pipa, but some contributions from African and Caribbean rookeries were also observed. Oceanographic data corroborated the local origins, but showed higher connection with West Africa and none with the Caribbean. High correlation was observed between origins estimated through genetics/rookery size and oceanographic/rookery size data, demonstrating that ocean currents and population sizes influence haplotype distribution of Brazil's hawksbill populations. The information presented here highlights the importance of national conservation strategies and international cooperation for the recovery of endangered hawksbill turtle populations. © 2014 Proietti et al. Source

Santos R.G.,Federal University of Alagoas | Pinheiro H.T.,University of California at Santa Cruz | Pinheiro H.T.,California Academy of Sciences | Martins A.S.,Federal University of Espirito Santo | And 4 more authors.
Proceedings of the Royal Society B: Biological Sciences | Year: 2016

Group formation is a common behaviour among prey species. In egg-laying animals, despite the various factors that promote intra-clutch variation leading to asynchronous hatching and emergence from nests, synchronous hatching and emergence occurs in many taxa. This synchrony may be adaptive by reducing predation risk, but few data are available in any natural system, even for iconic examples of the anti-predator function of group formation. Here, we show for the first time that increased group size (number of hatchlings emerging together from a nest) reduces green turtle (Chelonia mydas) hatchling predation. This effect was only observed earlier in the night when predation pressure was greatest, indicated by the greatest predator abundance and a small proportion of predators preoccupied with consuming captured prey. Further analysis revealed that the effect of time of day was due to the number of hatchlings already killed in an evening; this, along with the apparent lack of other anti-predatory mechanisms for grouping, suggests that synchronous emergence from a nest appears to swamp predators, resulting in an attack abatement effect. Using a system with relatively pristine conditions for turtle hatchlings and their predators provides a more realistic environmental context within which intra-nest synchronous emergence has evolved. © 2016, Royal Society of London. All rights reserved. Source

Bellini C.,Projeto TAMAR ICMBio | Santos A.J.B.,Fundacao Pro TAMAR | Grossman A.,All Angle Imagens LTDA | Marcovaldi M.A.,Fundacao Pro TAMAR | Barata P.C.R.,Fundacao Oswaldo Cruz
Journal of the Marine Biological Association of the United Kingdom | Year: 2013

In this paper, information is presented on green turtle (Chelonia mydas) nesting on Atol das Rocas (Rocas Atoll), north-eastern Brazil. The temporal distribution of nesting events per season, annual number of nests, carapace length of nesting females, clutch size, hatching success, incubation period, internesting interval, clutch frequency, observed reproductive lifespan, and remigration period are reported. The study period included the nesting seasons from 1990 to 2008, but no regular beach monitoring was carried out in 1998 and 1999. Two sorts of methods were applied to the estimation of the annual number of nests in some seasons. Taking into account the estimated annual numbers of nests, the mean annual number of nests in the study period, excluding 1998-1999, was 335 (standard deviation = 139, range = 136-563, N = 17). An analysis of the available data indicates that the average nesting levels at the beginning of the study period (the first five seasons) and at its end (the last five seasons) were roughly the same. The mean curved carapace length of the nesting turtles decreased significantly during the study period, from 115.9 cm in 1990-1992 to 112.9 cm in 2006-2008. Atol das Rocas was established as a federal biological reserve in 1979, but regular sea turtle conservation activities actually started there in 1990. Since that year, the killing of nesting turtles has ceased, nesting activity by the turtles can proceed in an undisturbed fashion, and their clutches can incubate in a protected environment. Copyright © Marine Biological Association of the United Kingdom 2012. Source

Lima E.P.,Projeto TAMAR ICMBio | Wanderlinde J.,Fundacao Pro TAMAR | De Almeida D.T.,Fundacao Pro TAMAR | Lopez G.,Fundacao Pro TAMAR | And 2 more authors.
Chelonian Conservation and Biology | Year: 2012

Loggerhead turtle (Caretta caretta) nesting in the Southwest Atlantic has been monitored for decades, but information from northern Rio de Janeiro State (Brazil) has been lacking until now. In this study, we documented 11,086 nests laid between the 1992/1993 and 2010/2011 nesting seasons (∼1000 nests per season) and found significant variations in incubation period and hatching success among in situ and relocated nests. Because loggerhead nests in Rio de Janeiro are presumed to produce a large proportion of male hatchlings because of lower average incubation temperatures, this area is an important component of loggerhead population biology and conservation in Brazil and the southwest Atlantic region. © 2012 Chelonian Research Foundation. Source

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