Transcript for Tracking the Elusive, Super Intelligent Sperm Whale
We're about to take you on an underwater adventure with some of nature's biggest beasts. Sperm whales. Turns out they're sending all kinds of signals and some of them might just be aimed at us. Can we crack their code? ABC's Matt Gutman takes the plunge into whale world. Reporter: From the blue abyss, the sperm whale, Earth's largest predator, cruising by. Making those clicks. Listen. Packed with information but what kind? And free drivers beside them on a quest to crack that alien code. We've been looking for intelligent life in the universe for the past 50 years, spending hundreds of millions of dollars. Yet there is intelligent life here. It's in the sea. Reporter: With only fins, snorkels and cameras these underwater aquanauts have spent the past six years gathering these close encounters and never before seen images. The researchers they've their 17-pound brains, the largest in the animal kingdom, pack intelligence. But mostly over the centuries the whales were thought of as a commodity. Their teeth used for ivory, blubber for oil, wax, and soap. Even their tendons used for guitar strings. Hunted for centuries, the whales nearly went extinct. Shockingly, some fought back. Herman Melville's "Moby dick" enshrined in literary history and later on the silver screen. And this year, the Chris Helms worth flick "Heart the sea." A movie based on the true story of a ship rammed by a sperm whale. It sank and few of its crew survived. And it's still happening. These fishermen aboard this Chilean fishing vessel, at first amused, then alarmed as a sperm whale rams their boat. But Fred and fabric believe not only are these animals gentle giants but they have an advanced language they are using, get this, to try to communicate with us. Do you think you'll be able to communicate back? Cracking the code of a sperm whale would be a dream. Reporter: We flew from Miami to Antigua to the caribbean island of Guadalupe to join them. Driving through lush mountain rain forests to this tiny harbor. Our initiation into the challenges of whale research starting early. This is the way you earn your breakfast. Reporter: Rowing through rain in a little sail boat operated by a curmudgeonly captain, think of him as captain ahab. Fabri fabrice's station, that speaker. On the other end a hydrophone and underwater microphone, receiving and listening for whale clicks. The noise when we connect. I like this. It's this kind of thing. You just compress information. Reporter: Those clicks of information so precise, some marine biologists believe they must contain complex messages about food, danger, or even about their friends and families. Hearing them enables fabric to count and decipher whether the whales are forging thousands of feet below for food or congregating in pods to check the surface. They like to be in deep water where there's a shelf? Yes, they like canyons. That's where they hunt. Reporter: It takes a few hours to pick up the trail. Most researchers who study whales do this. But almost none do this. Swim with the wild up to 50-ton subjects. Mostly because so little is known about their behavior. There's a reason no one's doing what they're doing. It takes extreme patience. It's really hard. Reporter: James nester is the author of the book "Deep" which in part chronicles the obsession of these two makeshift whale researchers. Fred and fabric have spent thousands of hours at sea but only had about 40 encounters with sperm whales. What's the protocol? Once we get in the water we should wait for them to come at us and make them curious. They have to initiate the encounter. Reporter: And then dive below. Why free dive with them? Free diving is a big advantage because we don't make noise. A scuba diver makes bubbles and that's a lot of news under water. Reporter: A merman if there ever was one. He may have captured a whale calf born minutes earlier. Its tail or fluke is unfolded, umbilical cord still attached. He and fabric have filmed humpback whales out of mature rishs. Killer whales in Norway. Watch this predator slice through a school of herring. On our first day we strike out. The next morning we wait, back out again. One of the problems with finding whales has been this weather, pummeling us the past couple of days. Very, very windy which makes it hard to spot the whales. Reporter: The tropical rains leave quickly and it's back to the speaker and that tantalizing click, click, click of the whales. That's 1:00 just in front of us. Reporter: Finally, we're close. This is the moment we've been waiting for. They've been very elusive. Now's our chance. Right there. Reporter: We suit up and jump in as one shoots a puff of spray into the air and then dives below. Did you see that? Okay. Go very slow. Reporter: The water filled with clicks. They're scanning us from below, maybe 100 feet, maybe 3,000. But make no mistake, the aliens are here. But how deep? We just can't see them. This is more like a game of chess than a rodeo. What we've been trying to do is go in the water, get them accustomed to us, hop back out, follow them some more. The idea is for them to come to us, not us to chase them. Reporter: Turns out on this day, the world's largest predator is shy. We go down again but can't follow. The whales will be back as they have for 15 million years and for as long as they can keep going, so will Fred and fabric. For "Nightline," I'm Matt gunman on the shores of Guadalupe.
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