Abstract

A multi-institutional study was undertaken to understand and resolve problems of infertility and high embryonic and hatchling morbidity and mortality in a population of green sea turtles (Chelonia mydas) held in a mariculture setting (Cayman Turtle Farm). Unusual epithelial and oral lesions were documented in thousands of hatchlings over several years. Dietary micronutrients, such as carotenoids, have been linked with fertility and embryonic and neonatal survival and health in various taxa^1-4, and preliminary evidence suggests that they were deficient in the diet of this population. Eggs laid by females at Cayman Turtle Farm contained an average carotenoid concentration 5-fold lower than that found in the eggs of wild conspecifics, which is likely to reflect dietary differences. Certain carotenoids are the sole metabolic precursors for vitamin A biosynthesis⁴, so carotenoid deficiency may have significant implications for health and reproduction. Indeed, while extensive analysis of eggs, bloodwork, and tissues revealed a myriad of infectious and non-infectious problems, lesions consistent with hypovitaminosis A were a common underlying factor. Serum and liver samples from both captive individuals and wild "control" animals were analyzed for vitamin A and lutein levels. This information will advance our understanding of the nutritional needs of farmed green sea turtles and may be used to improve turtle conservation and captive care worldwide.

Acknowledgements

The authors wish to thank students Nathan Robinson and Melanie Wright for their hard work in helping to collect samples, Janice Blumenthal for organizing sample transportation, and every staff member at the Cayman Turtle Farm that has contributed their time and dedication for the survival of this species. We would also like to recognize the University of Florida for donating control samples for this study.

References

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