脆弱天堂 01

The South Pacific is on the face of it， still a healthy ocean.

We depend on it.

Over 60% of the world's fish catch comes from the Pacific.

But like all oceans, it has little or no protection,so it may not stay healthy much longer.

So what's being done，one to preserve its natural treasures?

And what does the future hold for this fragile paradise?

For the South Pacific, this is a critical time.

It's changing in ways that, if left unchecked,could develop into a global crisis.

Some of its residents have been through crisis before.

Humpback whales were hunted so relentlessly during the last century that their numbers crashed by 90%.

But recently, they've made a comeback, surging from 5,000 to 60,000 animals.

Their blubber is no longer boiled down，for oil.

Today, these whales are greeted by boats loaded not with harpoons, but with tourists.

The waters of Tonga are one of the few places in the world where it's legal to get in and meet the giants face to face.