References of "Guirlet, Elodie"
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See detailMaternal transfer of chlorinated contaminants in the leatherback turtles, Dermochelys coriacea, nesting in French Guiana
Guirlet, Elodie ULg; Das, Krishna ULg; Thomé, Jean-Pierre ULg et al

in Chemosphere (2010), 79(7), 720-726

We examined the maternal transfer of organochlorine contaminants (OCs), pesticides (DDTS and HCHs) 26 and polychlorinated biphenyls (PCBs), and the temporal variation of blood and eggs concentrations from ... [more ▼]

We examined the maternal transfer of organochlorine contaminants (OCs), pesticides (DDTS and HCHs) 26 and polychlorinated biphenyls (PCBs), and the temporal variation of blood and eggs concentrations from 27 38 leatherback turtles (Dermochelys coriacea) nesting in French Guiana. PCBs were found to be the dom- 28 inant OCs with respective mean concentrations of 55.14 ng g 1 lipid-mass for egg and 1.26 ng mL 1 wet- 29 mass for blood. OC concentrations were lower than concentrations measured in other marine turtles 30 which might be due to the lower trophic position (diet based on gelatinous zooplankton) and to the loca- 31 tion of their foraging and nesting grounds. All OCs detected in leatherback blood were detected in eggs, 32 suggesting a maternal transfer of OCs. This transfer was shown to depend on female blood concentration 33 for RDDTs and for the most prevalent PCB congeners, since significant relationships were found between 34 paired blood–egg concentrations. During the nesting season, OC concentrations in eggs and the percent- 35 age of lipid in eggs were found to decline in successive clutches, highlighting a process of offloading from 36 females to their eggs and a decreasing investment of lipid from females into their clutches. OCs in eggs 37 tended to be higher in females spending 3 years in the foraging grounds between two nesting seasons 38 than in those spending 2 years, suggesting an impact of time spacing two breeding seasons, called remi- 39 gration interval, and of location of the foraging grounds. [less ▲]

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See detailEffect of tidal overwash on the embryonic development of leatherback turtles in French Guiana
Guirlet, Elodie ULg; Caut, Stéphane; Girondot, Marc

in Marine Environmental Research (2010), 69

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See detailEtude des facteurs écologiques et écotoxicologiques impliqués dans la réussite d’incubation chez la tortue luth, Dermochelys coriacea, de Guyane Française
Guirlet, Elodie ULg

Doctoral thesis (2008)

Leatherback turtles, Dermochelys coriacea, have relatively low hatching success in comparison to other marine turtle species. This low hatching rate is largely a result of high embryonic mortality rather ... [more ▼]

Leatherback turtles, Dermochelys coriacea, have relatively low hatching success in comparison to other marine turtle species. This low hatching rate is largely a result of high embryonic mortality rather than infertility, but the specific causes remain unknown. Leatherbacks are vulnerable to excessive adult mortality (resulting in population decline) because they are long-lived species. However, low hatching success and corresponding low juvenile recruitment could also result in long term declines of leatherbacks. On the Yalimapo beach, in French Guiana, hatching success is lower for this species than on other nesting sites, emphasising the problem of recruitment for the population. Understanding the causes of low hatching success is therefore an important conservation step towards preventing extinction in this population. During my thesis, I investigated the role of ecological (predation and nest site location) and ecotoxicological factors (blood and egg contamination by trace elements and organochlorine compounds) on the hatching success of leatherback nests. Firstly, nest location was shown to have an important effect on predation and inundation rate that decreased hatching success. Secondly, a maternal transfer of contaminants from females to their eggs was confirmed, raising the issue of the deleterious effects of environmental contaminants on embryos development, a developmental stage very sensitive to contaminants. Dose-effect relationships between contaminants and hatching success need to be assessed to establish the risk of environmental pollution for leatherback reproduction. Moreover, the use of stable isotope analysis for females differing in the number of years between two reproductive seasons revealed that they used different feeding areas. These feeding grounds differed in their geographical location, but also in the quality of the available prey in terms of their level of contamination by environmental pollutants, highlighting the issue of adult contamination. This thesis confirmed the importance of ecological factors for hatching rate and highlighted the existence of ecotoxicological factors, which have not yet been studied for the leatherback turtle. [less ▲]

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See detailSkipping 2 or 3 years for reproduction: the environmental determinant and the evolutionary consequences
Girondot, Marc; Georges, Jean-Yves; Guirlet, Elodie ULg

Conference (2008, January)

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See detailIsotope Analysis Reveals Foraging Area Dichotomy for Atlantic Leatherback Turtles
Caut, Stéphane ULg; Guirlet, Elodie ULg; Angulo, Elena et al

in PLoS ONE (2008), 3(3), 1845

Background: The leatherback turtle (Dermochelys coriacea) has undergone a dramatic decline over the last 25 years, and this is believed to be primarily the result of mortality associated with fisheries ... [more ▼]

Background: The leatherback turtle (Dermochelys coriacea) has undergone a dramatic decline over the last 25 years, and this is believed to be primarily the result of mortality associated with fisheries bycatch followed by egg and nesting female harvest. Atlantic leatherback turtles undertake long migrations across ocean basins from subtropical and tropical nesting beaches to productive frontal areas. Migration between two nesting seasons can last 2 or 3 years, a time period termed the remigration interval (RI). Recent satellite transmitter data revealed that Atlantic leatherbacks follow two major dispersion patterns after nesting season, through the North Gulf Stream area or more eastward across the North Equatorial Current. However, information on the whole RI is lacking, precluding the accurate identification of feeding areas where conservation measures may need to be applied. Methodology/Principal Findings: Using stable isotopes as dietary tracers we determined the characteristics of feeding grounds of leatherback females nesting in French Guiana. During migration, 3-year RI females differed from 2-year RI females in their isotope values, implying differences in their choice of feeding habitats (offshore vs. more coastal) and foraging latitude (North Atlantic vs. West African coasts, respectively). Egg-yolk and blood isotope values are correlated in nesting females, indicating that egg analysis is a useful tool for assessing isotope values in these turtles, including adults when not available. Conclusions/Significance: Our results complement previous data on turtle movements during the first year following the nesting season, integrating the diet consumed during the year before nesting. We suggest that the French Guiana leatherback population segregates into two distinct isotopic groupings, and highlight the urgent need to determine the feeding habitats of the turtle in the Atlantic in order to protect this species from incidental take by commercial fisheries. Our results also emphasize the use of eggs, a less-invasive sampling material than blood, to assess isotopic data and feeding habits for adult female leatherbacks. [less ▲]

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See detailMaternal transfer of trace elements in leatherback turtles (Dermochelys coriacea) of French Guiana
Guirlet, Elodie ULg; Das, Krishna ULg; Girondot, Marc

in Aquatic Toxicology (2008), 88

In sea turtles, parental investment is limited to the nutrients and energy invested in eggs that will support embryonic development. Leatherback females have the largest clutches with the biggest eggs of ... [more ▼]

In sea turtles, parental investment is limited to the nutrients and energy invested in eggs that will support embryonic development. Leatherback females have the largest clutches with the biggest eggs of the sea turtles and the highest reproductive output in reptiles. The migration between foraging sites and nesting beaches also represents high energy expenditure. The toxicokinetic of pollutants in the tissues is thus expected to vary during those periods but there is a lack of information in reptiles. Concentrations of essential (Copper, Zinc, Selenium) and non-essentials elements (Cadmium, Lead, Mercury) were determined in blood (n = 78) and eggs (n = 76) of 46 free-ranging leatherback females collected in French Guiana. Maternal transfer to eggs and relationships between blood and eggs concentrations during the nesting seasonwere investigated. All trace elementswere detectable in both tissues. Levels of toxic metals were lower than essential elements likely due to the high pelagic nature of leatherbacks that seems to limit exposure to toxic elements. Significant relationships between blood and egg concentrations were observed for Se and Cd. Se could have an important role in embryonic development of leatherback turtles and Cd transfer could be linked to similar carrier proteins as Se. Finally, as multiple clutcheswere sampled from each female, trends in trace elements were investigated along the nesting season. No change was observed in eggs but changeswere recorded in blood concentrations of Cu. Cu level decreased while blood Pb levels increased through the nesting season. The high demand on the body during the breeding season seems to affect blood Cu concentrations. Calcium requirement for egg production with concomitant Pb mobilization could explain the increase in blood Pb concentrations along the nesting season. [less ▲]

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See detailPhenology of marine turtle nesting revealed by a statistical model of the nesting season
Girondot, Marc; Rivalan, Philippe; Wongsopawiro, Ronald et al

in BMC Ecology (2006)

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See detailInfluence of nest location and infertile eggs on hatching success of leatherback turtle nests in French Guiana
Caut, Stéphane; Guirlet, Elodie ULg; Jouquet, Pascal et al

in Canadian Journal of Zoology (2006), 84

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