Nature & Environment

Study Decodes Mystery of 'Lost Years' of Newly Hatched Baby Sea Turtles

Benita Matilda
First Posted: Mar 05, 2014 06:57 AM EST

Satellite transmitters on the shells of young loggerhead sea turtles help scientists track the mysterious journey of newly hatched baby sea turtles.

The study suggests that the young sea turtles head to the sea to avoid being attacked by predators. On moving away from the continental shelf, the sea turtles remain on the surface where they receive ample sunlight.  They seek refuge in seaweed found on the water surface.

The life of the sea turtle is both fascinating as well as mysterious. The moment a young turtle hatches, it makes its way into the waters and disappears for years before returning to the shores as a large juvenile. This time period is often referred to as 'lost years' as scientists were earlier clueless on how the young ones battled for life in the oceanic environment.

But the new finding provides clues about the early behavior and movement of the newly hatched sea turtles.

This remarkable discovery was made by scientists from the University of Central Florida, University of Miami Rosenstiel School of Marine and Atmospheric Science, University of Wisconsin and Florida Atlantic University.

"Before this study, most of the scientific information about the early life history of sea turtles was inferred through genetics studies, opportunistic sightings offshore, or laboratory-based studies. With real observations of turtles in their natural environment, we are able to examine and reevaluate existing hypotheses about the turtles' early life history. This knowledge may help managers provide better protection for these threatened and endangered species,"said UCF biologist Kate Mansfield, who led the team.

The lost years of the juvenile sea turtles were followed  using tiny solar powered satellite transmitters that were mounted on the shells of the young loggerhead sea turtles. The researchers tracked 17 loggerhead turtles for 27-220 days.

The researchers noticed that the young turtles did not constantly stay in the currents linked with the North Atlantic subtropical gyre, they hopped in and out of the currents.

According to the zoologist Warren Porter at the University of Wisconsin-Madison, the juveniles opt for habitats that supply them with their needs and also offer the growing turtles a metabolic boost.

The small sea creatures were seen taking shelter in seaweed called sargassum that moves along with ocean currents.

 "So there is food for the turtles there, and there is concealment, too," Porter says. "Once these little loggerheads get through the initial swimming frenzy, the first few hours of their life, they find a place and just sit there. They're very hard to see in the sargassum, as long as they're not moving."

The researchers believe that the small cold blooded sea creatures obtain thermal benefit by staying at the surface of the sea. The transmitters revealed the temperature near the turtle's shell was 4-6 degree Celsius warmer than the sea surface temperature.

"This is the first data to document the thermal benefits of surface living for oceanic juvenile sea turtles," says Alan Bolten of the Archie Carr Center for Sea Turtle Research at the University of Florida in Gainesville.

This finding offers clues about the food and water requirements of the sea animal as well as the habitat it survives in. Using this data, conservationists can offer better protection for the threatened and endangered species.

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