Spying on Whales: The Past, Present and Future of the World’s Largest Animals
Nick Pyenson
Whales are among the largest, most intelligent, deepest diving species to have ever lived on our planet. We have hunted them for thousands of years and scratched their icons into our mythologies. They simultaneously fill us with waves of terror, awe and affection – yet we know hardly anything about them.Whales tend to only enter our awareness when they die, struck by a ship or stranded in the surf. They evolved from land-roaming, dog-like creatures into animals that move like fish, breathe like us, can grow to 300,000 pounds, live 200 years and roam entire ocean basins. Yet despite centuries of observing whales, we know little about their evolutionary past.In this remarkable new book, the Smithsonian’s star palaeontologist Nick Pyenson takes us to the ends of the earth and to the cutting edge of whale research as he searches for the answers to some of our biggest questions about these graceful giants. His rich storytelling takes us deep inside the Smithsonian’s unparalleled fossil collection, to frigid Antarctic waters, and to the arid desert of Chile, where scientists race against time to document the largest fossil whalebone site on earth.Spying on Whales is an illuminating story of scientific discovery that brings readers closer to the most enigmatic and beloved animals of all time.
Copyright (#ulink_e9e9fdd7-ef86-5345-8f93-d27b4d07138f)
William Collins
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This eBook first published in Great Britain by William Collins in 2018
Copyright © 2018 by Smithsonian Institution
Illustrations © 2017 Alex Boersma
Cover illustrations by Alex Boersma
First published in the United States of America by Viking, an imprint of Penguin Random House LLC in 2018 as Spying on Whales: The Past, Present, and Futureof Earth’s Most Awesome Creatures
The author asserts the moral right to be identified as the author of this work.
A catalogue record for this book is available from the British Library.
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Source ISBN: 9780008244460
Ebook Edition © June 2018 ISBN: 9780008244484
Version: 2018-06-04
Dedication (#u10c389c6-365b-5c13-98a2-de3559c7340f)
Every author writes with a very specific reader in mind.
I wrote this book for you.
And for my family.
Epigraph (#ulink_3a25ab3f-d748-5cbc-bc7f-681d74e03f47)
What have we been doing all these centuries but trying to call God back to the mountain, or, failing that, raise a peep out of anything that isn’t us? What is the difference between a cathedral and a physics lab? Are not they both saying: Hello? We spy on whales and on interstellar radio objects; we starve ourselves and pray till we’re blue.
—Annie Dillard, Teaching a Stone to Talk
For the animal shall not be measured by man. In a world older and more complete than ours, they move finished and complete, gifted with the extension of the senses we have lost or never attained, living by voices we shall never hear. They are not brethren, they are not underlings: they are other nations, caught with ourselves in the net of life and time, fellow prisoners of the splendour and travail of the earth.
—Henry Beston, The Outermost House
Contents
Cover (#u8a80e695-a711-5cb1-b895-da63e702d4f8)
Title Page (#u7ccdb890-2022-512f-bdf2-9c500da663c2)
Copyright (#u7dbaf7ee-6d47-539c-94eb-55abf2ce8fbf)
Dedication
Epigraph (#udccc2b1c-0a92-5fdd-a5fb-c822b91b0aa3)
Map (#u91b888c1-ae16-5eb3-9dfd-8fca92bde202)
Prologue (#u3c580ba0-edef-520f-9d20-03aceb312efc)
PART I: PAST (#u392f58f8-42d9-580e-8bae-18a091b12a31)
1. How to Know a Whale (#u8cbff200-f789-5a00-b417-2afc0814cff0)
2. Mammals Like No Other (#u83de00cb-d9f9-5b25-ade1-a2bf7c80066e)
3. The Stories Bones Tell (#u4745a733-a050-5697-8d60-a2760b7f108c)
4. Time Travel on the Fossil Whale Highway (#u38bc3f33-8939-5f88-9f71-d2521cdb13b2)
5. The Afterlife of a Whale (#u9229b02e-8e5b-5ef2-9ce6-ba9ee9f22104)
6. Rock Picks and Lasers (#u4dd3fa4b-2b6b-5c81-b555-e91a8e17f795)
7. Cracking the Case of Cerro Ballena (#u1a093eac-8be3-523d-848d-d5786c003b07)
PART II: PRESENT (#u67317a16-0847-5fe6-8b0e-2e5d9207a50b)
8. The Age of Giants (#ue509a6e3-753f-5deb-9aaa-142b221b782c)
9. The Ocean’s Utmost Bones (#u8562c184-cab4-596a-a480-1cad867bf68e)
10. A Discovery at Hvalfjörður (#ua18c3e52-a9b2-57bb-968f-abb9031284d9)
11. Physics and Flensing Knives (#u1476002c-2ee9-51b6-bd4c-72ccd1aa38e7)
12. The Limits of Living Things (#uab4303fd-9c8c-593c-ad28-599058bc1525)
PART III: FUTURE (#u37aca9b2-ab8f-53bc-b071-30e635e0547c)
13. Arctic Time Machines (#u2c448c0a-9bc9-5a1b-8e53-bf4bb0014806)
14. Shifting Baselines (#u01e75b1b-d7a8-57df-8a25-f0cbbf5466fb)
15. All the Ways to Go Extinct (#uf73ccebd-6917-5e54-a9d2-581e2515af0e)
16. Evolution in the Anthropocene (#uac09aaa3-bfee-5ee3-a531-130dfabbf873)
17. Whalebone Junction (#ucf1736a0-23ab-5f5a-9f95-ade76c02dc6b)
Epilogue (#u349c74ed-21bc-5dc0-bcd1-581f2f052301)
A Family Tree of Whales (#uf1b5f1b8-b929-5d80-9bf6-5448a5515df5)
Notes (#udaa43af6-f379-5047-8ce3-b1e78d1a5232)
Selected Bibliography (#u4bdb62fa-28d0-5f23-8595-87427a8749a8)
Index (#u43f46f39-1fef-500a-871d-5ac51b9cc871)
Acknowledgments (#u03c94590-627c-575f-bd5a-897035fc2029)
About the Publisher (#u8f15d16b-16c5-5bbf-aa0a-9772e3dbabf6)
Map (#ulink_d02977cf-fa27-5797-8700-9366856c17e5)
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At this very moment, two spacecraft move at over thirty-four thousand miles per hour, about ten billon miles away from us, each carrying a gold-plated copper record. The spacecraft, Voyager 1 and Voyager 2, are meant as messengers: they carry information about our address in the solar system, the building blocks of our scientific knowledge, and a small sampling of images, music, and greetings from around the world. They also carry whalesong.
The long squeaks and moans on the record belong to humpback whales. In the 1970s, when the Voyager mission launched, our view of whales was rapidly changing, from game animals to cultural icons and symbols of a nascent environmental movement. Scientists had recently discovered that male humpbacks produce complex songs, composed of phrases collected under broader themes, nested like Russian dolls that repeat in a loop. Humpback whalesong has evolved even since we started listening as each new singer improvises on the loop, creating new structures and hierarchies that constantly change over years, and across ocean basins.
Whalesong, however, remains a riddle to anyone who isn’t a humpback whale. We can capture its variation, details, and complexity, but we don’t know what any of it truly means. We lack the requisite context to decipher and understand it—or, really, any part of cetacean culture. Even so, we send whalesong into interstellar space because the creatures that sing these songs are superlative beings that fill us with awe, terror, and affection. We have hunted them for thousands of years and scratched them into our mythologies and iconography. Their bones frame the archways of medieval castles. They’re so compelling that we imagine aliens might find them interesting—or perhaps understand their otherworldly, ethereal song.
In the meantime, whales here on Earth remain mysterious. They live 99 percent of their lives underwater, far away from continuous contact with people and beyond most of our observational tools. We tend to think about them only when we glimpse them from the safety of a boat, or when they wash up along our shores. They also have an evolutionary past that is surprising and incompletely known. For instance, they haven’t always been in the water. They descend from ancestors that lived on land, more than fifty million years ago. Since then, they transformed from four-limbed riverbank dwellers to oceangoing leviathans, in a chronicle we can read only from their fossil record, a puzzle of bone shards unevenly spread across the globe.
The little we have learned about whales leaves us unsatisfied because the scales of their lives and facts of their bodies are endlessly fascinating. They are the biggest animals on Earth, ever. Some can live more than twice as long as we do. Their migrations take them across entire oceans. Some whales pursue prey with a filter on the roof of their mouth, while others evolved the ability to navigate an abyss with sound. And then they speak to one another with impenetrable languages. All the while, in the short clip of our own history, we’ve moved from heedlessly hunting them to an awareness that they have culture, just as we do, and that our actions, both direct and indirect, put their fate in jeopardy.
A paleontologist is a good tour guide for what we know about whales, not just because their evolutionary history is profoundly interesting. It’s because we, as paleontologists, are used to asking questions without having all of the facts. Sometimes we’re losing facts: fossils removed from their medium lose clues of context; promising bonebeds are razed to make room for roadways; or bones lay misidentified in a museum drawer. When faced with these challenges, paleontologists turn to inference, drawing on many different lines of evidence to understand processes and causes that we cannot directly see or study—the same approach used by any detective, really. In other words, thinking like a detective is a useful approach to confront the mysteries posed by the past, present, and future of whales.
This book is not a synoptic, comprehensive account of every different species of whale—there are far too many whales to fit into anything shorter than an encyclopedia. Instead, this book presents a selective account, a kind of travelogue to chasing whales, both living and extinct. I describe my experiences from Antarctica to the deserts in Chile, to the tropical coastlines of Panama, to the waters off Iceland and Alaska, using a wide variety of devices and tools to study whales: suction-cupped tags that cling to their backs; knives to dissect skin and blubber from muscles and nerves; and hammers to scrape and whack away rock that obscures gleaming, fossilized bone.
The narratives in this book group into three general sections: past, present, and future. Broadly, I want to answer questions about where whales came from, how they live today, and what will happen to them on planet Earth in the age of humans (a new era that some scientists call the Anthropocene). But these stories don’t cleanly fit into these three temporal silos. Instead, they build on one another and reciprocate because the ways that we need to think about whales require thinking about all the evidence at hand: unraveling the many mysteries of living whales requires a background about their evolutionary past, just as much as the surprises from the fossil record can clarify the meaningful facts about their lives today and into the future.
The first part of the book tells the chronicle of how whales went from walking on land to being entirely aquatic, relying on evidence from the fossil record showing what the earliest whales looked like. These fossils show us details that we couldn’t otherwise know about the history of whales, and I explore exactly how we dig up these clues in the first place. Following fossil whale bones brought me to the Atacama Desert of Chile, where my colleagues and I puzzled over an ecological detective story with the discovery of Cerro Ballena, the world’s richest fossil whale graveyard. How did this site come about, and what does it tell us about whales in geologic time?
The second part examines how and why whales became the biggest creatures ever in the history of life. The challenges of studying organisms as large as the largest species of whales means thinking about the limits of biology, and what exactly organisms at these superlative scales need to do, on a daily basis, to sustain their enormous sizes. While trying to connect muscle to bone at a whaling station, I share another serendipitous find: the discovery of an entirely new sensory organ in whales. What does an organ, lodged right at the tip of a whale’s chin, mean for how, when, and why baleen whales evolved to become all-time giants?
Lastly, the third part explores the specter of the uncertain future that we share with whales on Anthropocene Earth. In the twentieth century alone, whaling in the open oceans killed more than three million whales, reducing many populations to shadows of their baseline abundances. Despite this decimation, no single species went extinct until the first decade of the twenty-first century. Since then, not a whistle or splash of the Yangtze river dolphin has been recorded, and responsibility for the extinction of this species can be placed squarely on our shoulders: we dammed the only river in which it lived. Other species, such as the vaquita, remain on the extinction watch list, numbering fewer than one dozen or two dozen individuals. But the news from the field isn’t entirely dire: some whale species have rebounded from the brink, even expanding to new habitats as climate and oceans change. What can we imagine about our shared future with whales, drawing on their lives today and what we know about their evolutionary past?
Ultimately, the quest to understand whales is a human enterprise. This book is a story not just about knowing whales but also about the scientists who study them. The scientists described in these stories come from a variety of different disciplines, ranging from cell biology and acoustics to stratigraphy and parachute physics. Some are historical but very much knowable through their writings, their specimen collections, and the intellectual questions that they asked. One of the great privileges of my professional life is the opportunity to work at the Smithsonian, which has afforded me not only the latitude to undertake this pursuit but also firsthand access to some of the world’s largest and most important collections of material evidence, be it specimens, scientific journals, or unpublished field notes. Every day, I think about the many generations of scientists before me who handled this same evidence, scratching away at the very same questions, while constrained by the circumstances of their times. My hope is that this book says as much about the inner lives of scientists as it does about whales.
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I sat transfixed by a sea littered with a million fragments of ice, all rising and falling in time with the slow roll of the waves. We had spent the morning looking for humpback whales in Wilhelmina Bay, threading our rubber boat between gargantuan icebergs that were tall and sharp, like overturned cathedrals. Now we stopped, cut the engine, and listened in the utter stillness for the lush, sonorous breath of an eighty-thousand-pound whale coming to the water’s surface. That sound would be our cue to close in. We had come to the end of the Earth to place a removable tag on the back of one of these massive, oceangoing mammals, but we took nothing for granted in Antarctica. As we sat waiting on the small open boat, I came to feel more and more vulnerable, a speck floating in a sea of shattered ice. “Don’t fall in,” my longtime collaborator and friend Ari Friedlaender deadpanned.
I struggled to remember how long we had been away from the Ortelius,our much larger oceanic vessel with its ice-hardened steel hull. In every direction, we were enclosed by a landscape of nunataks, jagged spires of rock that pierced the creamy tops of surrounding glaciers. Where the glaciers met the sea, they ended in sheer, icy cliffs towering over the bay. Without a human structure for scale, these landforms seemed both near and far at the same time. This otherworldly scene of ice, water, rock, and light warped my sight lines, bending my sense of distance and the passage of time.
If you hold your fist with your left thumb out, your thumb is the western Antarctic Peninsula; your fist, the Antarctic continent’s outline. The Gerlache Strait is part of a long stretch of inner passageway along the outer side of Antarctica’s left thumb, and Wilhelmina Bay cuts a rough cul-de-sac off the Gerlache. The Gerlache is a hot spot for whales, seals, penguins, and other seabirds, and Wilhelmina Bay is the bull’s-eye. All come here to hunt for krill, small crustaceans that form the centerpiece of Antarctic ocean food webs. Consider your hand again: individual krill are about the length of your thumb, but whales pursue them because they explode into great aggregations, or swarms, during the Antarctic summer. With the right mixture of sunlight and nutrient-rich water, dense clouds of krill form a sort of superorganism that can stretch for miles and concentrate in hundreds of individuals per cubic foot. By some measures, there is more biomass of krill than of any other animal on the planet. Calorie-rich swarms of them lurked somewhere, not far, just under our boat.
Where there are krill in sufficient quantities, there will be whales, but the fundamental problem with studying whales is that we almost never see them, except when they come to the surface to breathe or when we dive, in our own limited fashion, in search of them. Whales are inherently enigmatic creatures because the parameters of their lives defy many of our tools to measure them: they travel over spans of whole oceans, dive to depths where light does not reach, and live for human lifetimes—and even longer.
In Wilhelmina Bay our goal was to attach a sleek plastic tag to the back of a whale to record audio, video, depth, changes in the whale’s speed, and even pitch, yaw, and roll. Our tags would provide crucial context for how humpbacks interact with their environment by relaying, in a time-stamped way, how they feed on krill. Ari and his colleagues have tagged and tracked whales along the Antarctic Peninsula for nearly two decades, charting their movements against the backdrop of changes in krill-patch density, water temperature, daylight, and other variables. As climate change warms the poles faster than the rest of the planet, every year counts.
I sat on the gunnel of the boat while Ari scanned from the bow. We were several days into a multiweek expedition with high hopes to tag as many humpbacks as possible—ideally, a pod feeding together—but thus far we had been skunked. Ari stood rigid like a figurehead, holding a twenty-foot-long carbon-fiber pole in folded arms. The pole flexed in synchrony with the swell, the teardrop-shaped tag bobbing at one end. I watched clouds shift slowly overhead, mirroring the dappled quicksilver of the water, and wondered whether any other place on Earth could feel as alien as Antarctica. Then a loud gurgle interrupted my daydreaming, followed by a trumpeting blast of water vapor bursting from flaring, paired nostrils. A whale’s blow.
We knew to expect more plumes of water immediately thereafter. A pod of whales synchronize when they surface to breathe—sometimes nearly simultaneously or split seconds apart. They usually breathe a few times in a row, in quick succession, before resubmerging—unless they’re asleep or truly exhausted, whales tend to act like surfacing is a nuisance and they’d rather be deep underwater. Their tight coordination in breathing likely has a lot to do with maximizing time spent below the surface engaged in the cooperative tasks of finding food and avoiding predators. Some species travel or hunt in pods that are tightly knit family genealogies, while others, such as the humpbacks before us, form short-lived associations, seemingly a matter of happenstance.
“Oh, that’s right,” Ari called out. The vapor from the blow lingered in the cold air. Ari pointed to a small patch of water a dozen yards from the boat, perfectly calm against the waves at the surface. This patch, called a flukeprint, betrayed the whale’s movement, unseen deep below our tiny boat. The single flukeprint bloomed into several, each the size of our boat, rising up from the depths, whirling and spreading into the smooth geometry of a lily pad. We were right. “He’s got buddies,” Ari said. Without the aid of an echo sounder—which would also tip off the whales about our location—we used the ephemeral patterns on the surface to read their path.
We started up the engine, throttling ahead slightly to a spot beyond the last flukeprint. Within seconds, right on cue, a pair of enormous nostrils bubbled at the surface, releasing a thundering tone and then a spray that carried past us as we kept up with the whale. A dorsal fin surfaced, and a second and third blow exploded nearby. “Pull up behind this last one. We have about three more breaths until they go down,” Ari shouted.
We trailed the laggard of the group, maneuvering the boat into position. Ari lowered himself across the bow and held the pole against his torso, extending the tip with the tag just ahead of the dorsal fin as we motored close to the behemoths moving yards away. Then, in a decisive motion, Ari launched the tip of the pole toward the whale’s back, where the tag’s suction cups hit the skin with a satisfying thwack. The whale rolled beneath the surface as we pulled back to pause and wait for it to return. We spotted its sleek, shiny back as it arose again, marked with a neon tag, and we cheered. The whale took one last breath before it raised its monstrously wide tail flukes out of the water and slipped down into emerald darkness with the others. Ari radioed back to the Ortelius. “Taaaaag on,” he said with a hint of swagger as he grinned at me.
Tag on
The whole rodeo of tagging is a bit like sticking a smartphone on the back of a whale, complete with the logistics of getting close enough to a forty-ton mammal in the first place. Just as your smartphone can record movies, track where you go, and automatically rotate images, the same technology—miniaturized and cheap, combining video, GPS, and accelerometers all in one device—has fueled a revolution in understanding how animals move throughout their world. Scientists call this new way of recording organismal movement biologging, and it has captured the interest of ecologists, behavioral biologists, and anatomists, all interested in knowing the details of how animals move through space and over time. Biologging has been especially important for revealing the daily, monthly, and even annual meanderings of animals that are extremely difficult to study. Stick a tag on a penguin, a sea turtle, or a whale, and there’s a chance to know how it swims, what it eats, and everything else it does whenever you’re not around to watch it—which is most of the time, for animals at sea.
The logistics of studying whales places them in a realm truly apart from every other large mammal on land or at sea. To know anything about them in the wild takes time on a boat, sticking a tag on their back, sliding a camera underwater, or spying overhead with a drone—if you’re lucky enough to come upon them in the first place. Biologging is helping us overcome this challenge by giving us a remote view into their lives, an extension of our senses more intimate and sometimes more detailed than any telephoto lens. In the case of humpbacks, tag data have revealed how these gulp-feeding whales lunge at large schools of krill and other prey, oftentimes in coordinated attacks. It’s a form of pack hunting, which might seem strange for a species celebrated as gentle giants. But baleen whales are serious predators, not like grazing cows but more like wolves or lions, pursuing their quarry with strategy and efficacy. Don’t be fooled by their lack of teeth, or just because krill don’t bleat in terror.
Hours later the Ortelius prowled silently through Wilhelmina Bay, with a pair of massive spotlights leading the way in search of icebergs in our path. Outside on the bow, I watched heavy snowflakes drift through the cones of light as Ari unfolded the metal radio antenna that would lead us back to our tag. The tags we were using had to be re-collected to yield their data; we would have to find and physically pluck them out of the water, provided that they’d already been knocked off the whales’ backs. By design, they can last minutes, hours, or even days from the force of suction alone, before being scraped, being bumped, or falling off. Its buoyant neon housing would keep the whole device floating on the surface until we triangulated its position.
Over the course of his career, Ari has probably tagged more species of whales than anyone, in all circumstances and in every ocean. Beyond friendship, mutual colleagues, shared ambitions, and wry humor, we were working together in Antarctica to build a bridge between our disciplines—paleontology for me, ecology for him—because questions about how whales evolved to become masters of ocean ecosystems over fifty-odd million years need to be grounded in the facts of what whales do today. Bridging gaps between disciplines sometimes necessitates spending time side by side. All the better if it’s in the field.
The metal prongs that Ari assembled looked like an elaborate set of rabbit ears from an old television set. He plugged the antenna into a small receiver with a speaker, and after a few moments, we heard a series of intermittent beeps. “That gap between the beeps tells us that the whale is sleeping, rising up to the surface to breathe, and then sinking back down.” Ari smiled. “Just dozing, belly full of krill. Not a bad way to spend a Saturday night.” We would need to come back later and listen again for our tag until it floated freely, beeping uninterrupted.
Most large baleen whale species alive today belong to the rorqual family, which feed on krill and other small prey by lunging underwater. They comprise the more familiar members of the cetacean bestiary, including humpbacks, blue whales, fin whales, and minke whales. Rorquals are also the most massive species of vertebrates ever to have evolved on the planet—far heavier than the largest dinosaurs. Even the smallest rorquals, minke whales, can weigh ten tons as adults, about twice as much as an adult bull African elephant. Rorquals are easy to distinguish from any other baleen whale, such as a gray whale or a bowhead whale: look for the long, corrugated throat pouch that runs from their chin to their belly button. (And yes, whales have belly buttons, just like you and me.) The features that make rorquals so obviously different from other baleen whales also play a critical role in how they feed.
Across whole ocean basins, individual whales find their food using probability, heading for feeding grounds burned into memory from a lifetime of migration. Rorquals travel routes that span hemispheres over the seasons; an individual whale might migrate from the tropics in the winter in search of mates and to bear young, then to the poles during the summer to forage under constant sunlight. Baleen whales still retain olfactory lobes, unlike their toothed cousins, such as killer whales and dolphins, which have lost them. Baleen whales might smell some aspect of their prey at the water’s surface, and it is possible that this mechanism could refine their search once on the scene. Originally their sense of smell evolved for transmission through air, not water; we know little beyond the basics about this sense in whales. Somehow, whales manage to be in the right place at the right time to feed. And what’s clear from biologging is that once in the right place, baleen whales spot the prey patches from below, probably approaching them by sight. Lacking the echolocation of their toothed relatives, vision is likely the dominant sense for baleen whales at short range.
With prey in range, a rorqual accelerates, fluking at top speed, and begins the amazing process of a lunge. Surging from below, it opens its mouth only seconds before it arrives at a patch of krill or school of fish, which may be as big as or bigger than the entire whale. When it lowers its jaws, the rorqual exposes its mouth immediately to a rush of water that pushes its tongue backward, through the floor of its mouth, into its throat pouch. In mere seconds, the accordion-like grooves of its throat pop out like a parachute. After engulfing the prey-laden water, the whale slows, almost to a halt, pouch distended and looking bloated, nothing like its airfoil-shaped profile from moments prior. Over the next minute, it slowly expels water out of its mouth through a sieve of baleen, until its throat pouch returns to its original form, the prey swallowed. For their part, krill and fish deploy collective defensive behavior by dispersing to try to escape the oncoming maw of death. In the end, a successful whale takes a bite out of a much bigger, more diffuse and dynamic superorganism.
Lunge feeding has been described as one of the largest biomechanical events on the planet, and it’s not hard to imagine why when you consider that an adult blue whale engulfs a volume of water the size of a large living room in a matter of seconds. Tags on humpbacks in other parts of Antarctica show how they sometimes feed close to the seafloor in pairs, swimming alongside each other as they scrape the bottom with their protruding chins in mirrored unison. Tags have also shown us that rorquals are right- or left-handed, just like us, favoring either a dextral or sinistral direction when they roll their bodies to feed.
The more scientists tag whales, the more it’s apparent that there’s still much that we don’t know. It turns out that blue whales have a behavior where they spin 360 degrees underwater in a pirouette before they lunge, probably to line up their mouths precisely with a patch of krill. Other lightweight tags, launched with barbs that cling more deeply beneath the skin on the dorsal fin, have tracked the movement of Antarctic minke whales migrating over eight thousand miles of open ocean, from the Antarctic Peninsula to subtropical waters. These tags upload data directly to satellites whenever the whale surfaces, over the course of weeks to months, before eventually falling out. These tags are also especially useful for species that are rarely seen, such as beaked whales. Satellite-linked dive tags deployed on Cuvier’s beaked whales revealed, in a precise way, the astonishing extremes of their foraging dives for squid and fish—over 137.5 minutes of breath holding, 2,992 meters deep—data that set new dive records for a mammal. If the idea of holding your breath for over two hours doesn’t alarm you, imagine doing it while chasing your dinner to a depth of nearly two miles.
Tag data combined with tissue samples taken from biopsy darts tell us that these humpback whales feeding in the western Antarctic Peninsula are merely seasonal visitors for the austral summer. By early fall, they depart the icy bays, cross the great Circum-Antarctic Current that rings the seventh continent, and undertake various paths over thousands of miles to arrive at temperate latitudes. At Wilhelmina Bay the overwhelming majority of humpbacks return to the low latitudes of the Pacific coasts of Costa Rica and Panama to mate and give birth before returning to the Southern Ocean for the next austral summer to feed.
We eventually retrieved the tag, along with its data, and continued to Cuverville Island, on the other side of Wilhelmina Bay. As the Ortelius maneuvered out of the Gerlache and toward the island, I watched from the ship’s stern as we passed icebergs more massive than any I had yet seen. Their fragmented sides, a hundred feet high, were etched in luminous, milky blues and grays. They held light from sea to sky, glowing in unearthly ways, as if they could not have been formed on this planet. And of course they were mostly sheathed underwater, which was a bit of an ominous thought; the Ortelius kept a careful distance. But the incomprehensibility of something as overwhelming as an iceberg is belied by its transience: even the largest ones, platforms the size of cityscapes, will eventually shed their layers of ice, annealed over hundreds of thousands of years, and become part of the sea.
Scattered around the peninsula are several islands like the one we approached, islands that served as barely inhabitable platforms for whaling operations in the early and midtwentieth century. Today the only remnants of human civilization are occasional concrete pylons with bronze plaques identifying the area as an open-air heritage site, and leftover whale bones. After we hauled our rubber boat up on the rocks, I walked toward the spoil piles of green-stained and weathered whale bones, strewn like spare lumber at a construction site.
Reading whale bones is what I do, although sometimes I feel like the bones find me. I’ve spent so much time searching for them, cataloging them, and puzzling over them that my brain immediately recognizes even the slightest curve or weft of bone. Whale bones tend to be relatively large, so finding them is often largely a matter of making sure that you’re in the right neighborhood—it shouldn’t have been much of a surprise, especially on the grounds of an abandoned whaling station. On the island I mentally inventoried the first assemblage I encountered, as I dodged foot-tall gentoo penguins scrambling at my feet: ribs, parts of shoulder blades, arm bones, and fragments of crania. They clearly belonged to rorqual whales, about the size of humpbacks, or possibly even fin whales. Some of the more intact vertebrae were artfully balanced upright on the shoreline, probably posed by Antarctic tourists, passing through the peninsula by the thousands in the austral summer and looking for a perfect photograph.
If these bones belonged to humpback whales, it would not be surprising, given the abundance of this species out around Antarctica today. It’s likely that some of the whales that we tagged were descendants of these individuals, belonging to the same genetic lineage. But history tells us that if you turned back the clock a century, humpbacks probably wouldn’t have been the only ones here: blue and fin whales would have numbered in the hundreds, if not thousands; minke whales, beaked whales, and even Southern right whales would also have been part of the community. Ari has seen only one right whale out of the thousands of whales that he’s observed over fifteen years in the area. Southern right whales have barely recovered from two hundred years of whaling, and we know little about where they go besides their winter breeding grounds along protected coastlines of Australia, New Zealand, Patagonia, and South Africa.
It’s not just right whales that vanished. There’s no memory or record of just how many of any kind of whale there was in the Southern Ocean, in terms of their abundance, before twentieth-century whaling killed over two million in the Southern Hemisphere alone. However, as whale populations in this part of the world slowly recover from this devastation, we’re beginning to see what that past world might have looked like. On an expedition in 2009, Ari and his colleagues documented an extraordinary aggregation of over three hundred humpbacks in Wilhelmina Bay, the largest density of baleen whales ever recorded. “There is no external limit on these whales because there is just so much krill. They literally cannot eat enough before they need to leave,” Ari reflected. “That incredible resource base means that it’s just a matter of recovery time for whales—and I think what we saw in the bay that year was a glimpse of what their world was once like, before whaling.” On the whole, humpbacks have recovered to only about 70 percent of their prewhaling numbers in the Southern Ocean, although along the peninsula their population size has nearly returned to the best estimates of prewhaling levels at the start of the twentieth century.
I paused on a guano-free ledge to record a few observations about the bones’ weathering and their measurements in my field notes. To the southwest, the sky churned in a dark gray, portending wind and snow, and I felt a chill creep into my damp toes and fingertips. I pulled off my gloves and reached for a disposable hand warmer in my jacket pocket. Lodged in a mess of receipts and lozenge wrappers was a note my son had left me on the kitchen counter back home:
Im gona mis you
wen you go to
anaredica.
The night before I left my home in Maryland we traced the expedition route on a plastic globe. When he wanted to know how far away eight thousand miles was in inches, I didn’t tell him the answer that I wanted to, which was “Too far.” I reassured him that the passage was safe and that we would stay warm. “I’ll think about you when we drink hot cocoa,” I offered, dressing up my own concerns with a good smile.
As we pulled away from Cuverville Island to return to the Ortelius, the swirling clouds began to send down flurries, covering us in thick, wet snow. The boat bumped hard against the waves, and we saw humpbacks surfacing far off in the distance, the wind pushing their blows quickly behind them. The sight of those living, breathing, feeding whales in the same view as the island with beach-cast bones made me feel as though I could see the present and past simultaneously, each telling us facts that the other vantage could not. The bones on Cuverville Island and Ari’s tagging work in the Gerlache were each a unique window into the story of humpback whales in the Antarctic, though these views were terribly incomplete: the past represented by mere bones crumbling on remote shores, what we know today limited to a few hours’ or days’ worth of data collected by a hitchhiking recorder on whales’ backs.
Scientists tend to operate within intellectual silos because of the years of training and study that it takes to know about any single part of the world. But the best questions in science arise at the edges. Ari and I both want to know how, when, and why baleen whales evolved to become giants of the ocean—Ari wants to know more about their ecological dominance today, and I want to know what happened to them across geologic time. The answer to the basic question about the origin of whale gigantism requires pulling data and insights from multiple scientific disciplines, which is another way of saying that we need the perspectives of different kinds of science—and scientists—to untangle the monstrous challenges of the nearly inaccessible lives of whales. That’s why a paleontologist like me was on a boat tagging whales at the end of the Earth: I needed a front-row seat to know exactly what we can hope to know from a tag. But answering the questions that most captivate me about whales requires more than just a single tag. It means wrapping my arms around museum specimens, handling microscope slides, paging through century-old scientific literature, and wading knee-deep in carcasses.
The wind sapped the last warmth from my already-wet gloves and whipped through openings around my hood as I held tight to the ropes on the gunnels. The first scientists to visit this place, over a hundred years ago, didn’t have the luxury of disposable hand warmers. They suffered more brutally than we can really imagine, with less certainty of safe return. In these narrow margins they must have wrestled with the tension that overcomes scientists in the field: the desire to apprehend something almost unknowable against the tolls of living a world away from civilization. I patted my son’s note, folded safely inside my jacket pocket. Hot cocoa sounded just right.
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