Transcript for Show explores the world beneath the ocean's surface

Finally tonight, the stunning new images from beneath the sea. The sharks, the dolphins, even the tusk fish. Here's ABC's James Longman. Reporter: Using advanced technology, producers of America's "Planet Earth: Blue plan et 2" were able to explore the world underneath the ocean's surface like never before. The ocean is such a giant part of our planet. Reporter: What was your favorite part? It was the day that we filmed this volcano. It's like I went to another planet that day. Reporter: Filming on every continent, cameras attached to suction caps placed on these whales, following their every move. Oh, my -- Reporter: Hungry sharks reminding the crew that this is their territory. Oh, he's pushing us. Go! Reporter: They were bumping at the sub? Yes. They got very territorial. But once they realized, no, that's a big yellow electronic thing, then they carried on just getting on with it. Reporter: Producers followed these tusk fish for six weeks, discovering new behaviors, using coral to crack open a golf-sized clam shell with his tiny mouth. It also highlights the effects of global warming an pollution. In Sarasota bay, dolphin's calves are dying. Clearly, something else is going on. Reporter: An estimated 8 million tons of plastic are dumps into the ocean each year. And the American scientist from the university of Georgia hopes this will make people think. There's a native American phrase, we don't inherit the Earth from our ancestors, we borrow it from our grandchildren. Everybody can do little things, and those little things add up and collectively, they make a huge difference. Our thanks to James Longman. And you can see it all at bbc America on demand. I'm David Muir. I hope to see you tomorrow. Anchor: That snow hours away

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