Seasonal Reproductive Cycle of the Kemp's Ridley Sea Turtle (Lepidochelys kempi)

Ultrasonographic and radiographic determination of egg development of jurarás (Kinosternon scorpioides) in captivity

“…In this experiment, the visualization of oviduct eggs just 180 days after ultrasonographic evaluation suggests the presence of vitellogenic follicles at different phases of development, as was observed in morphophysiological studies of Galápagos turtles by Robeck et al (1990), Rostal et al (1998), Schumacher & Toal (2001) and Wilkinson et al (2005).…”

“…In the same way, Robeck et al (1990), Robeck et al (1998), Rostal et al (1998) and Redrobe & Scudamore (2000) showed through hormone measurement serum calcium levels increase from the late nesting season to the mating season, which then declined in the nesting season. However, this increase was not statistically significant.…”

“…In Galápagos tortoise Casares et al (1997) and Rostal et al (1998) demonstrated vitellogenic follicles with the size ranging from 28 to 42mm of diameter. In the determination of estrogen seric values for sea turtles, these authors performed 247 ultrasonographic examinations, without distinction of vitellogenic follicles.…”

Size-related differences in feeding habitat use of adult female loggerhead turtles Caretta caretta around Japan determined by stable isotope analyses and satellite telemetry

“…In this study, loggerhead eggs were sampled to determine the stable isotope ratios of nesting turtles (Godley et al 1998). Based on several indices, Rostal et al (1998) concluded that vitellogenesis in Kemp's ridley Lepidochelys kempi begins 4 to 6 mo prior to the mating period and is completed prior to mating. Although it is not known when vitellogenesis begins and ends in loggerhead turtles, there is a possibility that the timing is similar to that in Kemp's ridley.…”

Efeitos de Fatores Ambientais na Reprodução de Tartarugas

“…O período de desova de Chrysemys picta marginata varia ao longo dos anos sendo mais fortemente correlacionado à temperatura média do ano anterior que à temperatura média dos meses anteriores (Christens & Bider, 1987). Os ciclos reprodutivos de Lepidochelys kempi são adaptados às condições ambientais, sendo que a maturação dos ovários e dos testículos ocorre no outono e inverno e o acasalamento e a desova ocorrem no verão quando as condições de incubação são mais adequadas (Rostal et al, 1998). Mortimer & Carr (1987) e Mortimer (1990) notaram que a estação de desova de Chelonia mydas coincide com o período de maior pluviosidade e temperatura, o que poderia constituir uma característica adaptativa, uma vez que as tartarugas têm dificuldades de abrir o ninho na areia muito seca e o substrato úmido facilita a escavação.…”