Ontogenetic diet shifts of green sea turtles ( Chelonia mydas ) in a mid-ocean developmental habitat

摘要: Green sea turtles (Chelonia mydas) arrive on the geographically isolated Bermuda platform as small juveniles and remain until they are approaching sexual maturity, at which point individuals depart for distant feeding nesting sites. It has been reported that younger green generally tend to carnivory or omnivory seagrasses become a significant food source grow. Evidence indicates grazing by in is negatively impacting seagrass beds, thus understanding their diets important both conserving food. Stable isotope methods were used investigate ontogenetic diet shifts of determine reliance larger turtles. Skin samples from 157 individual known turtle foods, plants animals, collected determination consumer δ13C δ15N values. A Bayesian stable mixing model analysis indicated wide range among turtles’ diets, with greatest differences occurring between large turtles; consumed almost exclusively. We also examined changes 12 captured two successive years; these recapture data confirmed suggested relationship size composition. Very limited evidence was found any variation would indicate shift away declining major source.