White sharks live longer than expected

White sharks can be more than 70 years old and so much older than previously thought. This report , after they had determined the age of eight already dead animals with a new procedure.

Researchers from National Oceanic and Atmospheric Administration (NOAA) and the Woods Hole Oceanographic Institution (WHOI) compared radiocarbon values from the shark vertebrae with reference chronologies documenting the marine uptake of carbon 14 produced by the atmospheric bomb testing.

Samples were dated and the result was the first radiocarbon age estimates for adult white sharks.

Estimated bomb radiocarbon dating age of the oldest female white shark sampled was 40, and for the oldest male 73. Ages for the three other males were 9, 14, and 44, while the other females sampled had estimated ages of 6, 21, and 32.

Previous studies of white sharks from the Pacific and Indian Oceans suggested that none of the examined specimens were older than 23 years.

Researchers suggest that either white sharks are living significantly longer and growing slower in the Northwest Atlantic than either the Pacific or Indian Oceans, or longevity has been underestimated in previous studies.

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