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What Makes Hawaii’s Green Sea Turtles Unique?


Hawaii is home to the largest hard-shelled sea turtles in the world. It is also the only place in the world where males haul out alongside females when they lay their eggs, and no one knows why.


- [Narrator] Female sea turtles of all species come ashore in order to lay their eggs.

But this is the only place in the world where males haul out alongside females.

No one knows why.

The males don't guard the eggs and the turtles don't mate here.

This exceptional behavior is a complete mystery.

Oceanic nomads.

Green sea turtles swim endlessly until they reach maturity, somewhere between 20 and 50 years.

Scientists don't know how long these prodigious seafarers live, but they suspect it's more than a century.

Cruising through clouds of plankton for decades allows algae and barnacles to grow on the platforms of their brown shells.

This provides great benefits for the barnacles, but as they accumulate, ferrying such a load can slow turtles down.

The barnacles attach themselves with organic cement.

They're permanent passengers unless knocked off in the tussle of turtle sex.

But there is a way to limit their growth with a little help from some friends.

These brown and yellow tangs can digest tough marine algae that grows along with the barnacles.

This helps the turtles by keeping their shells smooth, making it more difficult for new barnacle larvae to attach.


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