How long do sharks live? Recent studies using carbon radioisotopes suggest we've been underestimating the ages of sharks, especially older ones. An article by National Geographic quotes our ichthyologist emeritus, Dr. Gregor Cailliet on the challenges of aging sharks using calcified growth bands:
Gregor Cailliet, professor emeritus at California's Moss Landing Marine Laboratories who has been aging sharks since the 1970s, says the banding method leads to the good, bad, and the ugly.
“The good are the ones where the growth zones and validated ages are identical. The bad is when they don’t mean anything. The ugly are the ones in which there are discrepancies.”