Radiocarbon dating yields clues to endangered turtles and ocean ecosystems

New York Times : Above-ground nuclear tests from the 1950s through the 1970s greatly increased the amount of carbon-14 in the atmosphere. Although it’s not harmful to wildlife, it does accumulate in their tissues. In a recent paper , Kyle Van Houtan of Duke University and colleagues describe how they used radiocarbon dating to study an endangered species of sea turtle, the hawksbill. Using shell samples collected from museums and government archives, the researchers compared the amount of carbon-14 in the turtle shells with the amount of carbon-14 in a reference specimen, in this case, coral. From those data and from computer modeling of growth rates from studies of wild and captive turtles, the researchers were able to make several determinations, among them the turtles’ average life spans, their feeding habits, and how those habits are changing. In the process, they are also learning much more about key changes in the ecology of the world’s oceans.