Transcript for Scientists study humpback whales for clues on climate change impact
this evening to an ABC news exclusive. Our journey to the bottom of the Earth tonight, where scientists are convinced that humpback whales can tell us a lot about climate change and its widespread effects. ABC's James Longman is in Antarctica as scientists take a major step tonight. Reporter: A journey to the ends of the Earth. Speeding across the frozen wilderness of Antarctica, we're tracking groups of humpback whales. American scientists here using specially designed drones leading the search. We have sleeping whales up here. Can we get the tag pole ready? Reporter: We approach these awesome giants and get a view from above, gathering vital information that helps us better understand the impact of climate change. So, this is the whole point of this mission, to get as close as possible to these whales and tag them with these gps systems that can tell us so much more about their behavior. Across the antarctic peninsula, 87% of the glaciers here are receding, creating more hope water, which has actually helped grow the humpback population. But warming waters are threatening a small crustacean called krill, the main food supply for humpbacks and the bedrock of Antarctica's entire food chain. They represent the health of an ocean ecosystem. To be able to have enough food to support a whale, let alone a population of whales, all of these things have to combine together to promote life and promote food being there. Reporter: After days of attempts to tag a whale, the scientists zero in. This camera attached to the tracking device is successfully planted on the humpback. Brilliant! This work is also uncovering other dangers. Researchers finding plastics, heavy metals, even flame retardants in their systems. The science being pioneered here is some of the most important for the survival of our planet. This place is stunning, but more than that, it can tell us so much about the risks we all face. All right, James Longman, our thanks to you. And James will have much more on those contaminates they discovered inside the whales, plastics, those heavy metals James mentioned, that's later tonight on "Nightline," the journey to the edge, right here.
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