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In Carl Safina’s Voyage of the Turtle, he discusses at great length the behavior, anatomy, and physiology of sea turtles, focusing especially on the Leatherback, Dermochelys coriacea. Although he talks about many aspects of sea turtle biology, I will be focusing on the sensory biology, diving physiology, and thermoregulatory methods that Leatherbacks use as described in his book.

Safina talks in depth about the sensory biology of nesting Leatherback sea turtles, especially when it comes to light. He states that, at wavelengths less than 550nm, artificial light is not only a deterrent for nesting females, but it also confuses hatchlings during the frenzy period (47; 54). The frenzy period in hatchlings is the first 24-48 hours of a hatchling’s life that involves crawling to the ocean, getting into the ocean, and swimming constantly in order to reduce predation and find food. When they begin crawling out of the nest, hatchlings have a very strong attraction to light. They head towards the lightest area on the beach, which is usually the horizon when the sun is starting to rise. They follow the light until they enter the ocean, where they shift from using light to using their innate magnetic fields in order to navigate. However, areas that are undergoing heavy infrastructural development use a lot of bright light during the construction process, especially at night. The hatchlings mistake this light for the light that they are supposed to follow and often wind up heading away from the ocean. While in Fort Lauderdale, FL, Safina and Dr. Kirt Rusenko observed hatchlings’ behavior after emerging from the nest. Due to the many hotels, condos, homes, and stores, disorientation in hatchling sea turtles is very common. Hatchlings have been...

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...though the ambient temperature was about 14° C (179). Because Leatherbacks can occupy a wide range of environments, they are able to maintain their body temperature between 25 and 29° C, even in Artic waters (179). Their black skin and brown fat help them to generate heat, while their thick blubber helps them store heat. Their massive size, a body plan known as gigantothermy, also prevents heat loss by decreasing the amount of surface area that comes into contact with the cold (179, 181). Leatherbacks are also able to shunt blood flow to certain parts of the body to keep blood in their deeper tissues. Finally, counter-current heat exchangers in their hydrofoils keep their flippers cool while simultaneously maintaining an elevated core temperature (180).

Works Cited

Safina, C. (2006). Voyage of the Turtle: In Pursuit of the Earth's Last Dinosaur. New York: Holt