Up close with whales

The BBC has an article by James Nestor, author of Deep, about free-diving with whales:

Whales are extremely shy animals, making it hard to study them in their natural habitat. But a group of marine scientists has managed to record their behavior up-close by free-diving with humpbacks and sperm whales:

I'm floating in the Indian Ocean, six miles off the north-east coast of Sri Lanka. A sperm whale and her calf are facing me, a hundred and fifty feet away. I can see them swimming towards me, hissing, blowing steam and clicking loudly like a pneumatic drill. "Don't swim, don't move. They're watching us," whispers my guide, Hanli Prinsloo. She grabs my hand and pulls me beneath the surface where we watch a hazy black mass materialize. Details gradually emerge: a fin, a gaping mouth, a patch of white. An eye, sunk low on a knotted head, peers in our direction.
The mother is the size of a school bus; together, they look like submerged islands.
I never wanted to swim with sperm whales. I'm not an adrenaline junkie with a death wish and yet, against my better judgement, and my mother's protestations, I found myself floating in the open sea with a group of marine mammal scientists from Dare Win (Database Regional Whales and Dolphins), an independent non-profit research program started by Fabrice Schnoller, a former lumber store owner from Reunion, a French island territory in the Indian Ocean.
The gurgle of scuba equipment, submarines, and robots that are normally used to study marine life tend to spook whales. To avoid scaring them, the Dare Win team have abandoned much of this technology and use free-diving techniques instead, using only a mask, flippers, and a single breath of air to dive dozens of feet deep into the ocean.
With just one breath, it's possible for experienced free-divers to stay underwater for more than four minutes. Sperm whales (bottom photo) and humpback whales (top photo) are often attracted to the free-divers who look like no other marine mammal and, sometimes, with a little luck, welcome the divers into their pods for hours at a time.
Other people have dived with sperm whales, but usually only for a few minutes, and often for recreation. Dare Win is the first group to free-dive with them with the sole intention of collecting data.
Schnoller's methods are considered reckless by many marine mammal researchers. Sperm whales can be dangerous; they are the largest toothed predators on earth. They can weigh up to a hundred thousand pounds and grow up to sixty feet in length. They have a row of eight-inch-long teeth which they use to hunt giant squid at depths of nine thousand feet.
A sperm whale could swallow a human— a few humans— within a matter of seconds, without ever pausing to chew. According to historical records, they did that often. Whaling ship logs from the eighteenth and nineteenth centuries are filled with accounts of vicious attacks on sailing boats, rowing boats, and swimmers.
Paintings from that era (middle photo) depict scenes of enormous sperm whales causing mass destruction if anyone was foolish enough to hunt them.
Herman Melville's classic novel Moby-Dick was based on a real sperm whale attack that destroyed a whaling ship in 1820. Of the twenty-one crew members aboard the Essex, just eight survived and were rescued after more than eighty days at sea.
But the Dare Win team convinced me that many of the old logs and paintings were most likely exaggerations or in some cases outright fabrications.
Sperm whales, they said, don't want to eat humans; they only attack when they are attacked, and then only rarely. The old myths have been perpetuated because so few people have studied the animals.
Nonetheless, while swimming side-by-side with them, sperm whales can accidentally smother you, decapitate you with their tails, and many researchers believe they can also vibrate your body to death with their most intense vocalizations if they choose; they are the loudest animals on the planet. These vocalizations form part of their echolocation system; they send out a click from the front of their noses, then listen for the echoes that resonate in a fatty sac beneath their mouths.
It's the most precise and powerful form of biosonar ever discovered. They can detect a ten-inch-long squid from a thousand feet away and a human from more than a mile away. The clicks are so powerful they can penetrate flesh and allow whales to see not only where objects are, but what they look like from the inside out. In essence, sperm whales have X-ray vision.
Getting "scanned" in this way is not only incredibly loud, it can also be incredibly painful. One Dare Win researcher told me how he was diving with sperm whales a year ago ,and attempted to push a calf away from his camera. The calf's nose was vibrating so violently from the clicks that it paralysed the researcher's hand for four hours.
A different type of vocalization, using what are known as coda clicks, is also used to communicate with other sperm whales, and can be heard hundreds of miles away.
Dare Win researchers have recorded dozens of hours of these noises which they and a team of researchers from the University of Paris are now studying. They believe the coda clicks form a sophisticated language. Sperm whales have the largest brain ever identified, about five times larger than the human brain.

Rico says he's been free-diving in the Pacific (years ago), but never with whales...