At the Ogasawara Marine Center, we are working on a new method of tagging turtles called “living tags,” which are said to be permanent tags. The scales of a newborn green turtle’s back (black) and belly (white) are cut out to about 4mm square and are switched and replaced. This will leave a white spot on the black back and a black spot on the white belly. The spots gradually grow larger as they grow.
These tags are not used to identify the individual turtle, but to identify the age at which it was hatched. The living tag was developed in Malaysia in 1982, and has been implemented in the Caribbean side of Mexico and Colombia, where a green turtle with white spots on its back was reported to have returned as a parent 16 years later. And now, in 2005, the Marine Center conducted a trial release of living tags on hatchlings every year from 2006 to 2010, in combination with other plastic and metal tags. So far, living-tagged turtles released from Ogasawara have been found in Mie and Kagoshima Prefectures. If these living-tagged green turtles return to Ogasawara in the future, we will know how many years it takes for green turtles in Ogasawara to become parents, and how long the headstarted turtles survive.