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Registros recuperados: 26 | |
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Jordão,Juliana Costa; Bondioli,Ana Cristina Vigliar; Guebert,Flavia Maria; Thoisy,Benoit de; Toledo,Lurdes Foresti de Almeida. |
Sea turtles are marine reptiles that undertake long migrations through their life, with limited information regarding juvenile stages. Feeding grounds (FGs), where they spend most of their lives, are composed by individuals from different natal origins, known as mixed stock populations. The aim of this study was to assess genetic composition, natal origins and demographic history of juvenile green turtles (Chelonia mydas) at the Paranaguá Estuarine Complex (PEC), Brazil, considered a Natural World Heritage site. Tissue samples of stranded animals were collected (n = 60), and 700 bp mitochondrial DNA sequences were generated and compared to shorter sequences from previously published studies. Global exact tests of differentiation revealed significant... |
Tipo: Info:eu-repo/semantics/report |
Palavras-chave: Chelonia mydas; MtDNA; Feeding grounds; Mixed stock analysis; Connectivity. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-47572015000300346 |
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Poli,Camila; Mesquita,Daniel Oliveira; Saska,Cinthia; Mascarenhas,Rita. |
ABSTRACT Currently, plastics are recognized as a major pollutant of the marine environment, representing a serious threat to ocean wildlife. Here, we examined the occurrence and effects of plastic ingestion by sea turtles found stranded along the coast of Paraíba State, Brazil from August 2009 to July 2010. Ninety-eight digestive tracts were examined, with plastic found in 20 (20.4%). Sixty five percent (n = 13) of turtles with plastic in the digestive tract were green turtles (Chelonia mydas), 25% (n = 5) were hawksbills (Eretmochelys imbricata), and 10% (n = 2) were olive ridley (Lepidochelys olivacea). More plastic was found in the intestine (85%) than in other parts of the gastrointestinal tract. We observed complete blockage of the gastrointestinal... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Marine debris ingestion; Gastrointestinal blockage; Chelonia mydas; Eretmochelys imbricata; Lepidochelys olivacea. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212015000300265 |
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Roos, David; Pelletier, Dominique; Ciccione, Stéphane; Taquet, Marc; Hughes, George. |
Monitoring the abundance of green turtles (Chelonia mydas) is necessary to assess population trends and risks of collapse. This note presents a study aimed at comparing three techniques for the direct estimation of green turtle numbers in their foraging habitats (seagrass beds and reef flats). The experiment was carried out at Mayotte Island, Western Indian Ocean. The techniques involved were surveys by snorkel, and aerial surveys using a microlight aircraft and a paramotor. Each technique had shortcomings and advantages. While each technique provided estimations of turtle numbers only surveys by snorkel permitted identification of species and sex, whenever visibility and turtle behaviour permitted. Along the shorelines, and over foraging areas, the... |
Tipo: Text |
Palavras-chave: Foraging habitats; Snorkelling survey; Aerial survey; Abundance estimation; Chelonia mydas; Green turtle. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-432.pdf |
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Jensen, Michael P.; Dalleau, Mayeul; Gaspar, Philippe; Lalire, Maxime; Jean, Claire; Ciccione, Stéphane; Mortimer, Jeanne A.; Quillard, Mireille; Taquet, Coralie; Wamukota, Andrew; Leroux, Géraud; Bourjea, Jerome. |
Understanding how ocean currents impact the distribution and connectivity of marine species, provides vital information for the effective conservation management of migratory marine animals. Here, we used a combination of molecular genetics and ocean drift simulations to investigate the spatial ecology of juvenile green turtle (Chelonia mydas) developmental habitats, and assess the role of ocean currents in driving the dispersal of green turtle hatchlings. We analyzed mitochondrial (mt)DNA sequenced from 358 juvenile green turtles, and from eight developmental areas located throughout the Southwest Indian Ocean (SWIO). A mixed stock analysis (MSA) was applied to estimate the level of connectivity between developmental sites and published genetic data from... |
Tipo: Text |
Palavras-chave: Chelonia mydas; Green turtle; Juvenile; MtDNA; Drifting simulation; Connectivity; Mixed stock analysis; Southwest Indian Ocean. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00612/72443/71398.pdf |
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Bourjea, Jerome; Mortimer, Jeanne A.; Garnier, Julie; Okemwa, Gladys; Godley, Brendan J.; Hughes, George; Dalleau, Mayeul; Jean, Claire; Ciccione, Stephane; Muths, Delphine. |
To refine our understanding of the spatial structure of the green turtle (Chelonia mydas) populations in the South West Indian Ocean (SWIO), we analysed patterns of mitochondrial DNA (396 base pairs control region fragment) variation among 171 samples collected at five distinct locations (Kenya, Northern Mozambique, and three locations in the Republic of Seychelles: the Granitic, Amirantes, and Farquhar groups) and compared them to genetic data (n = 288), previously collected from 10 southern locations in the SWIO. We also analysed post-nesting satellite tracks (n = 4) from green turtles nesting in the Amirantes group. Pairwise comparisons of haplotype frequencies showed significant genetic differentiation amongst rookeries and suggest that the SWIO hosts... |
Tipo: Text |
Palavras-chave: Indian Ocean; MtDNA; Satellite tracking; Phylogeography; Management unit; Chelonia mydas. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00266/37732/36062.pdf |
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Taquet, Coralie; Taquet, Marc; Dempster, T; Soria, M; Ciccione, S; Roos, David; Dagorn, L. |
We studied the foraging rhythms of green sea turtles Chelonia mydas on the seagrass beds of N'Gouja Bay, Mayotte Island (Comoros Archipelago) with acoustic transmitters and moored listening stations. We monitored 8 tagged turtles (4 probable males, 3 probable females and 1 immature), from 70 to 109 cm curved carapace length (CCL), for durations ranging from 5 to 92 d. The turtles exhibited a regular diel pattern: they foraged mainly during the day (on average 87% of seagrass detections were between 06:00 and 18:00 h) and rested on the inner reef slope during the night. Night time feeding activities were observed on the seagrass bed when the night light was high. The presence of turtles on the seagrass bed at night was significantly correlated with a night... |
Tipo: Text |
Palavras-chave: Foraging rhythm; Listening station; Acoustic transmitter; Green sea turtle; Mayotte; Southwestern Indian Ocean; Chelonia mydas. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-3616.pdf |
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Rimblot, F; Fretey, J; Lescure, J; Pieau, C. |
Sexual differentiation of the marine leatherback turtle is sensitive to temperature. Incubation of eggs below 29 degree C results in 100% males, whereas incubationa bove 30 degree C results in 100% potential females at hatching. Therefore, the threshold temperature lies between 29 and 30 degree C as has been found for other marine turtles (Caretta caretta, Chelonia mydas ). Among hatchlings from natural nests in French Guiana, 10% were males, 20% were potential females and 70% had an intermediate phenotype. The sand temperature at 60 cm of depth, near one nest, was recorded and was found to vary between 29 and 30 degree C during the presumed thermosensitive period. These results will be useful to marine turtle hatcheries which seek to manipulate sex ratios... |
Tipo: Text |
Palavras-chave: Dermochelys coriacea; Chelonia mydas; Reptilia; Hatcheries; Natural populations; Incubation; Turtle culture; Eggs; Temperature effects; Sexual dimorphism. |
Ano: 1983 |
URL: http://archimer.ifremer.fr/doc/1983/acte-1241.pdf |
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Chambault, Philippine; De Thoisy, Benoît; Huguin, Maïlis; Martin, Jordan; Bonola, Marc; Etienne, Denis; Gresser, Julie; Hiélard, Gaëlle; Mailles, Julien; Védie, Fabien; Barnerias, Cyrille; Sutter, Emmanuel; Guillemot, Blandine; Dumont‐dayot, Émilie; Régis, Sidney; Lecerf, Nicolas; Lefebvre, Fabien; Frouin, Cédric; Aubert, Nathalie; Guimera, Christelle; Bordes, Robinson; Thieulle, Laurent; Duru, Matthieu; Bouaziz, Myriam; Pinson, Adrien; Flora, Frédéric; Queneherve, Patrick; Woignier, Thierry; Allenou, Jean-pierre; Cimiterra, Nicolas; Benhalilou, Abdelwahab; Murgale, Céline; Maillet, Thomas; Rangon, Luc; Chanteux, Noémie; Chanteur, Bénédicte; Béranger, Christelle; Le Maho, Yvon; Petit, Odile; Chevallier, Damien. |
Although it is commonly assumed that female sea turtles always return to the beach they hatched, the pathways they use during the years preceding their first reproduction and their natal origins are most often unknown, as it is the case for juvenile green turtles found in Martinique waters in the Caribbean. Given the oceanic circulation of the Guiana current flowing toward Martinique and the presence of important nesting sites for this species in Suriname and French Guiana, we may assume that a large proportion of the juvenile green turtles found in Martinique are originating from the Suriname–French Guiana beaches. To confirm this hypothesis, we performed mixed stock analysis (MSA) on 40 green turtles sampled in Martinique Island and satellite tracked 31... |
Tipo: Text |
Palavras-chave: Chelonia mydas; Developmental habitats; Immature green turtle; Migration routes; Mixed stock analysis. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00589/70079/68059.pdf |
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Chambault, Philippine; Dalleau, Mayeul; Nicet, Jean-benoit; Mouquet, Pascal; Ballorain, Katia; Jean, Claire; Ciccione, Stéphane; Bourjea, Jerome. |
Background A strong behavioural plasticity is commonly evidenced in the movements of marine megafauna species, and it might be related to an adaptation to local conditions of the habitat. One way to investigate such behavioural plasticity is to satellite track a large number of individuals from contrasting foraging grounds, but despite recent advances in satellite telemetry techniques, such studies are still very limited in sea turtles. Methods From 2010 to 2018, 49 juvenile green turtles were satellite tracked from five contrasting feeding grounds located in the South-West Indian Ocean in order to (1) assess the diel patterns in their movements, (2) investigate the inter-individual and inter-site variability, and (3) explore the drivers of their daily... |
Tipo: Text |
Palavras-chave: Chelonia mydas; Home range; Satellite tracking; Diel pattern; Tidal cycle. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00601/71269/69659.pdf |
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Pelletier, Dominique; Roos, David; Ciccione, Stéphane. |
The ability of captive-reared turtles to survive in the wild is not precisely known, nor are movements of immature turtles in the open ocean. To provide information on these issues, a satellite tracking experiment was conducted in the western Indian Ocean to monitor oceanic movements of immature green turtles. Two wild turtles and four captive-reared individuals were tracked. The latter had been displaced after birth from nesting sites to a distant rearing site. Wild turtles survived after release, but did not move far away from release site. We hypothesize that this resident behaviour may be explained by stage-specific habitat requirements. Captive-reared turtles survived after release and migrated over thousands of kilometres. Among these, the oldest... |
Tipo: Text |
Palavras-chave: Indian Ocean; Captive reared; Migration pattern; Satellite telemetry; Chelonia mydas; Marine turtle. |
Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/publication-573.pdf |
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Le Gall, Jean-yves; Bosc, Pierre; Taquet, Marc. |
A research programm on the marine green turtle Chelonia mydas nesting on the two major reproduction sites for the species in the Indian Ocean, conducled over last 15 years, included intensive tagging programm. Processing of these lagging data provides estimations of adult female populations {or each site and season from two independent methods. First classical method is the ratio of total number of nests produced over a define time on the mean individual number of nests by female during the same time (November, December, January). The computed mean individual number ranges from 3 to 3.5 obtained over 2 to 3 months. The second method is the multiple capture-recapture method (JOLLY, 1965; SEBER, 1965; MANLY, 1984). Il is an original tentative of applying... |
Tipo: Text |
Palavras-chave: Tortue verte; Chelonia mydas; Reproduckion; Ponte; Population; Femelles; Marquage; Recapture; Océan Indien.; Marine green turtle; Chelonia mydas; Capture; Recapture; Indian Ocean; Nesting; Populations; Tagging; Reproduction. |
Ano: 1986 |
URL: http://archimer.ifremer.fr/doc/00113/22406/20103.pdf |
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Bourjea, Jerome; Lapegue, Sylvie; Gagnevin, L; Broderick, D; Mortimer, J.a.; Ciccione, S; Roos, David; Taquet, Coralie; Grizel, Henri. |
Patterns of mitochondrial DNA (mtDNA) variation were used to analyse the population genetic structure of southwestern Indian Ocean green turtle (Chelonia mydas) populations. Analysis of sequence variation over 396 bp of the mtDNA control region revealed seven haplotypes among 288 individuals from 10 nesting sites in the Southwest Indian Ocean. This is the first time that Atlantic Ocean haplotypes have been recorded among any Indo-Pacific nesting populations. Previous studies indicated that the Cape of Good Hope was a major biogeographical barrier between the Atlantic and Indian Oceans because evidence for gene flow in the last 1.5 million years has yet to emerge. This study, by sampling localities adjacent to this barrier, demonstrates that recent gene... |
Tipo: Text |
Palavras-chave: Phylogeography; Mozambique Channel; Mitochondrial DNA; Indian Ocean; Control region; Chelonia mydas. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2185.pdf |
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Lescure, Jean; Cateau, Sidonie; Senegas, Jean Baptiste; Oliver, Guy; De Massary, Jean Christophe; Poisson, Francois; Cesarini, Catherine; Sacchi, Jacques. |
The presence of the Green Turtle, Chelonia mydas (Linnaeus, 1758) is very rare in Mediterranean French waters. There is no record before 1987. Thirteen records were reported from 1987 to 2014, eight during the five last years (five in 2014). This increase is mainly due to the recent development of survey network. Green Turtles are seen from June to September. |
Tipo: Text |
Palavras-chave: Chelonia mydas; Tortues marines; Méditerranée française; Espèce rare.; Chelonia mydas; Sea Turtles; French Mediterranean Sea; Rare species.. |
Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00312/42326/41656.pdf |
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Schouten, A.D.; Weijerman, M.; Tienen, L.H.G. van; Hoekert, W.E.J.. |
SCHOUTEN, A.D., WEIJERMAN, M., VAN TIENEN, L.H.G. & W.E.J. HOEKERT, 1997. Relocations of Sea Turtle nests of Lepidochelys olivacea, Dermochelys coriace and Chelonia mydas in the Galibi Nature Reserve, Suriname. Studies Nat. Hist. Caribbean Region 73, Amsterdam, 1997: 63-69. Relocation of nests of the marine turtles Lepidochelys olivacea (ESCHSCHOLTZ 1829), Dermochelys coriace (LINNAEUS 1758) and CHELONIA MYDAS (LINNAEUS 1758) in the Galibi Nature Reserve is performed to protect them from a number of hazards. The hatching percentage per nest is not significantly decreased by relocation, but the number of nests from which hatchlings emerge is greatly enhanced. In this situation relocation can be an effective conservation measure. |
Tipo: Article / Letter to the editor |
Palavras-chave: Dermochelys coriace; Marine turtles; Lepidochelys olivacea; Chelonia mydas; Emerging success; Hatching success; Suriname.; Nest relocations. |
Ano: 1997 |
URL: http://www.repository.naturalis.nl/record/503186 |
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Registros recuperados: 26 | |
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