Into the blue
The blue whale is at once the largest animal in the world and one of the most mysterious. It is the longest, heaviest and loudest living creature, and yet it can be remarkably inconspicuous. Only a tiny percentage of people will ever have the good fortune of seeing or hearing one in the wild. Humanity’s attitude toward blue whales is also full of contradictions. Ancient cultures, so far as they knew about the mightiest of sea creatures, mythologized them. Modern humans, by contrast, chased them to the bottom of the globe, blasted them with exploding harpoons and rendered hundreds of thousands of them into soap and margarine. Today, the blue whale’s place in our world has come full circle—once again held in awe, yet still little understood.
Perhaps the misunderstandings should not be a surprise. After all, the blue whale’s dimensions are so gargantuan that humans have a hard time comprehending them. If someone told you that the sun’s core temperature approaches 15 million degrees Celsius—which is true—would that figure have any real meaning? If another description increased the number by a few million degrees, would it seem any more implausible? The same issue seems to come up when describing blue whales: the animal’s physical characteristics are exaggerated, often to the point of absurdity, yet we don’t immediately notice. Many books and articles, for example, state that blue whales can be over 110 feet—a few stretch this to 115 feet—which almost certainly isn’t true. The 2007 edition of Guinness World Records tells us that a blue whale’s heartbeat can be heard up to 19 miles away, which is nonsense—no one has ever heard a blue whale’s heartbeat, let alone from that distance. Others claim that blue whale calls are as loud as jet planes, heavy-metal concerts, even undersea earthquakes, and that blue whales routinely communicate across thousands of miles of ocean. Their diet, according to the venerable National Geographic, is up to 8 tons of krill per day. Think about that for a second: 16,000 pounds of food in 24 hours. All fantastic tales, to be sure, and all inaccurate, unproven, or at the very least highly misleading. It is as though the truth about blue whales wasn’t astounding enough.
The truth is astounding, and it doesn’t need to be stretched. Blue whales are indeed the largest animals ever to inhabit the earth. Once in a while, someone asserts that the mightiest dinosaurs were larger, but until there is a reliable method of determining a dinosaur’s weight from a fossilized skeleton, this is pure speculation. Granted, a few dinosaurs may have been longer from tip to tail—although the longest scientifically measured blue whale was 98 feet, while the longest complete Diplodocus skeleton is less than 90 feet—but no prehistoric species has ever rivalled the blue whale’s mass, which likely exceeded 200 tons in the burliest individuals. The vast majority of blues never reach these dimensions, of course—most today average about 70 feet and weigh perhaps 70 tons, while those in the Antarctic are typically about 80 feet and 100 tons. By comparison, only the heaviest African elephants weigh more than 6 tons. Roger Payne, the pioneering American scientist who has lived among whales for more than 40 years, vividly recalls the first blue he ever encountered: "Although by then I had probably seen as many whales as anyone alive, this creature made me feel I had never seen a whale at all."1
One might think that an animal so large would be thoroughly understood by scientists. But of all the popular misconceptions about the blue whale, this may be the most glaring. We live in a world where scientific discoveries are often so remarkable, and so far removed from our everyday experiences, that they give the instead, they have a series of flexible, bristled plates called baleen, which they use to strain prey from the sea. The size and shape of these baleen plates varies radically—from less than 8inches to more than 10 feet—as each species has adapted to its preferred type of prey, whether fish, copepods or tiny shrimplike crustaceans called krill. While some baleen whales feed on a combination of these, blues are the pickiest of eaters and prey almost exclusively on krill.
The two groups differ in other ways: odontocetes have a single blowhole, while mysticetes have two. Male toothed whales also tend to be bigger than females—in the case of sperm whales and orcas, the difference is extreme. In baleen whales, however, females are larger. Odontocetes also use a sophisticated form of sonar to locate their prey, sending out high-frequency clicks and whistles and listening for their echoes, much as bats do when foraging in the dark for insects. Baleen whales also have a complex repertoire of sounds, as we will explore in detail, but they do not use them for echolocating prey.
The baleen whale suborder is diverse, but with a few exceptions, it is made up of giants. Right whales and bowheads, the first to be targeted by European whalers more than a thousand years ago, reach 50to 60feet. The little-known pygmy right whale, found only in the southern hemisphere, is about a third as long. Grey whales get as large as 40 to 45 feet. All other baleen whales are lumped together in the family Balaenopteridae and are known as rorquals. Their most obvious identifying feature is the series of grooves that extend some two-thirds of the way along the ventral surface, or underside, of their body. These pleats allow the animal to expand its mouth into a cavernous pouch—somewhat like a pelican or a bullfrog—thereby taking in vast quantities of water and prey. This evolutionary adaptation, as it turns out, was key to these animals becoming the largest inhabitants of the ocean.
The origin of the word rorqual is unclear. The Norwegian ro/r means groove, tube or channel, while hval means whale. Many popular sources, reasonably enough, say the word means something along the lines of "grooved whale," a reference to the throat pleats.
Most dictionaries disagree, however, and some trace the first syllable to an older Norse word for "red." While it seems odd to describe rorquals this way—each species is some combination of black, grey, blue or white—there may be an explanation. The ventral pouch is light coloured, and when extended it can take on a pinkish appearance as it gets flushed with blood. Whatever the etymology, the rorquals include at least seven species. The oddball is the humpback whale (Megaptera novaeangliae)—its gigantic white-bottom pectoral fins, rounded body and the bumpy tubercles decorating its head are unique. The remaining rorquals are all classified in the same genus, Balaenoptera, and are similar in appearance, differing mainly in coloration and size. If a non-specialist were to look at silhouettes of all six with no indication of the scale, the species would be almost impossible to identify. In addition to the distinctive throat pleats, they have smooth and streamlined bodies and a small dorsal fin located close to the tail stock.
The smallest and most abundant rorqual is the minke, usually divided into two species: Balaenoptera acutorostrata in the northern hemisphere and B. bonaerensis in the Antarctic. Minkes are typically 23 feet in length and were once considered far too small to be worth hunting, though today hundreds are killed annually by Japanese and Norwegian whalers. The Bryde’s whale (B. edeni), a tropical species reaching 49 feet, is the least understood rorqual, as it has never been hunted in great numbers. The slightly larger sei whale (B. borealis) is found in all oceans, usually at mid-latitudes, though it too was hunted in the Antarctic. The second-largest rorqual—and the second-largest animal on earth—is the fin whale (B. physalus), or finback, which is commonly 62 to 65 feet, though the largest females may exceed 85 feet. Finally, there is the grandest of them all—the blue whale (B. musculus ), which averages 69 to 72 feet outside the Antarctic. In the Southern Ocean, whalers took individuals that exceeded 98 feet and may have weighed as much as 200 tons.
The rorqual species are so closely related that they occasionally interbreed. Researchers in the North Atlantic have seen individuals that resemble both blue and fin whales on many occasions, and of southern Chile. They reliably visit waters off southern and western Australia, Indonesia and Madagascar; in the north-central Indian Ocean they occur off eastern Sri Lanka and the Maldives. Finally, about 2,000 blue whales still roam the Southern Ocean, all that is left of a population that once numbered about 240,000.
Researchers today visit many of these feeding sites annually to conduct surveys and compile catalogues of individual blue whales. The first continuous blue whale study, however, was not launched until 1979, when the American biologist Richard Sears started his work in the Gulf of St. Lawrence, and later expanded his study area to other parts of the Atlantic. The thriving population of blue whales off California appeared rather suddenly in the mid-1980s, and those in southern Australia and Indonesia were poorly known to science until the late 1990s. The rediscovery of the feeding ground in southern Chile—it had formerly been known to whalers—was announced with some fanfare in 2003. As for the blues off Madagascar and Sri Lanka, they remain largely unstudied.
Blue whale research is conducted almost entirely in summer, and not simply because the weather is more amenable—there is also the nagging problem that no one is sure where the animals go in the fall and winter. Like the sun slipping below the horizon, these massive creations simply vanish from our view until they are ready to reappear. No blue whale breeding ground has been found anywhere in the world’s oceans. For decades, biologists assumed that blues follow the same pattern as humpback and grey whales, who migrate from high-latitude feeding grounds in summer to tropical or subtropical waters to mate and calve. It now seems likely, however, that there are no specific areas where large numbers of blue whale females gather to give birth. Instead, they seem to disperse at the end of the feeding season, using a number of different areas to mate and calve, most of them hundreds of miles from shore.
Exactly where the enormous population of Antarctic blues went in the winter was one of the great mysteries pondered by whalers. Females with fetuses near full term, as well as mothers with newborn calves, were sometimes observed in winter near shore stations in southwestern Africa, but almost no blues have been seen in this region for decades. The most vivid account is from Saldanha Bay, South Africa, in 1912, and involved a 95-foot mother:
It had just given birth and was lying tired and still at the surface, when the whale-ship arrived and shot a harpoon into its back without it making any efforts to escape.
The calf was taken ashore. It was 7.03 metres long. The umbilical cord was still hanging on it, and the flukes were curled together. The most anterior baleen plates were just about to break through, while those at the back were already ca. 10 cm long. The ventral side was completely white in the grooved region, but behind had larger light-grey spots.2
Another blue whale birth—this one with a happier ending— occurred in 1946 when a very pregnant female became trapped in Trincomalee harbour, in eastern Sri Lanka. According to one report, a Royal Navy captain "approached the animal, attached a rope to her flukes, and proceeded to shift her into deep water."3 The whale immediately returned to the harbour, however, where she gave birth the following day. The heroic captain is said to have towed the mother again to open water, where it was later seen swimming freely, although the fate of the calf is not mentioned.
If anyone witnessed the actual calving in Trincomalee harbour, there is no description of it. The closest anyone has come to beholding such an event was likely the gruesome spectacle that occurred on whaling ships when a pregnant female was killed and winched onto the deck, where the fetus sometimes slipped spontaneously from its mother’s body. At some whaling stations, fetuses were routinely removed and measured, and in the late 1920s scientists were able to piece together a rough mating schedule for southern hemisphere blue whales: fetuses expelled in September averaged just over a foot in length, while those measured in December had grown to almost 7 feet. By April, fetal blue whales averaged 16 feet, still well shy of the typical birth length of about 23. The biologists extrapolated that the females visiting the Antarctic in the austral summer conceived between late June and late August, and that gestation was between 10 and 12 months. They also reasoned that if mothers nursed for seven months and then returned to their feeding grounds to recuperate before mating again, it was impossible for females to have more than one offspring every two years. Exactly when female blues reach sexual maturity is not known, though recent research suggests it happens at about age 10. And since multiple births in whales are extremely uncommon, each female produces no more than two, or perhaps three, calves in her first decade and a half. This exceptionally low reproductive rate—and humanity’s ignorance of it—would have terrible consequences for the blue whale.
Just as no scientist has ever observed a birth, none has ever been a voyeur during a blue whale coupling. Yet despite our almost complete ignorance of the species’ sex life—or perhaps because of it— accounts of the blue whale’s phallic grandeur abound. According to some, their penises are 16 feet long, and they can expel 400 gallons of semen in a single ejaculation. These claims, disappointingly, are nothing but urban legends. An adult blue whale’s penis is typically between 7 and 8 feet and the combined weight of the testicles— which were systematically measured during the whaling era—range from about 65 to 165 pounds. As in all whale and dolphin species, the male sexual organ is housed internally—swimming with a 7-foot penis exposed would be like driving a boat with the anchor hanging over the side—and is extruded through a genital slit when needed. Whale penises are tougher and more fibrous than those of other mammals, and it is believed that they use the elasticity of this tissue, rather than blood flow, to achieve an erection, but this process is not well understood. The world awaits a graduate student with the courage to study it.
The sexual organs and mammary glands of female blue whales are not conspicuous either. In fact, the vulva is not radically different in appearance from the genital slit in males, making it almost impossible for researchers to tell the boys from the girls during observations in the field. One sure way to identify a blue whale as female, however, is to spot one with a calf in tow—an adult seen close to a calf for any prolonged period is almost certainly its mother. Other adults, including the father, do not play a significant role during the seven months that the calf is nursing. Not that she needs the help—a lactating blue whale is a tremendous energy machine. Because whales must surface to breathe, they have evolved two adaptations that enable them to speed up the nursing process and minimize the time that mother and calf spend underwater. The first is breast milk with 35 to 50 percent fat—about ten times richer than cow’s milk—which is designed to accelerate the calf’s growth. In addition, like the pressurized hoses that quickly fill the fuel tanks of race cars at pit stops, the mother’s muscular action actively discharges the milk into the calf’s mouth during suckling. A fuel-injected calf can gain 40,000 pounds before being weaned, which works out to about 8 pounds an hour.
Other anatomical features of the blue whale are more mysterious. Blues are known to emit the most powerful vocalizations of any animals on earth, though many of their calls are at frequencies below the threshold of human hearing. How the animals generate such energetic sounds is completely unknown—no sound-producing organ or resonating membrane has been identified. Until someone figures out how to capture and study a live blue whale, this seems destined to remain unknowable.
Scientists do not even know how long blue whales live. Yet again, one needs to appreciate the challenge of answering this question. If an animal can never be kept in captivity, then scientists must somehow learn the year of birth and death of individuals in the wild, as they do with banded birds, or they must discover some body part than can indicate age, like the rings in a tree trunk. So far the oldest blue whale confirmed from direct observation is 38—it was first photographed in 1970 and sighted again in 2008. But scientists have been photo-identifying individual blue whales only since the 1980s, and older animals will undoubtedly turn up as long-term studies continue.
As for clues in the whales’ anatomy, there are several, though each has its own set of uncertainties. The oldest method for aging blue whales involves examining the ovaries of sexually mature females for knobs of tissue called corpora albicantia, which are laid down each time the animal ovulates. If this happens about once every two and a half years—traditionally considered the maximum rate at which blue whales can bear calves—and if females begin ovulating at age 10, then six corpora would indicate an age of about 25, while eight would translate to 30 years. The classic study of blue whale ovaries in the 1930s found a small number with more than 30 corpora, which would make the whales older than 85, and a Japanese scientist in the 1970s reported an individual with 40 corpora, suggesting the whale was 110 years old. But this method has at least two shortcomings. First, if biologists are wrong about the rate of ovulation, or the age at which females become sexually mature, their age estimates could be way off. If females ovulate every year and a half, for example, then 30 corpora works out to age 55, not 85. The other unknown is whether blue whales eventually stop ovulating. If so, they might live for decades afterward, as any menopausal woman will be quick to point out, and this method would be unable to determine their maximum lifespan. It is quite possible, however, that they keep breeding until they drop—biologists have examined pregnant fin whales that were known to be older than 40.
Scientists tried a second method of estimating age in the 1950s, when they discovered that rorquals have a wax plug in the outer ear made up of alternating layers of light and dark. These ear plugs have been just as problematic, however. To begin with, it was not at first clear whether the whales added a light layer one year, followed by a dark one the next, or if their annual growth consisted of both layers together. By the 1980s it became clear that the latter was the case for fin whales, at least, meaning that early age estimates may have been off by a factor of two. (Whether this is also true for blues is unknown, though the two species are similar enough that it is likely.) There is also lingering uncertainty about whether the ear plug method is reliable for very young or very old individuals. That said, biologists have found blue whale ear plugs with at least 46 (presumably annual) layers, and one female with 33 layers was pregnant when she was examined.
Taken together, all this evidence means blue whales can certainly live to 37, can almost surely exceed 50, and may well be among the longest-lived animals in the ocean. If a maximum lifespan of 90 to 100 years is ever proven, it would not surprise many scientists. Some truly remarkable evidence for the longevity of baleen whales comes from a third technique for establishing age, which involves measuring the presence of a certain amino acid in the lens of the eye. (Again, this method has never been used on blues.) Scientists in the late 1990s examined the eyeballs of 48 bowhead whales and found four that were well over 100 years old—the oldest was reportedly 211. If this sounds hard to believe—and the 211-year-old result may well be inaccurate—corroborating evidence keeps showing up in whales killed by aboriginal hunters. At least seven bowheads hunted since 1981 have been cut open to reveal fragments of old harpoon tips, some believed to date back to the 19th century—in May 2007, a bowhead killed off Alaska contained fragments of an exploding harpoon that was patented in 1879. Other researchers have discovered that the narwhal, a small Arctic species, can live to 115 years old, though a comparable study on minke whales found a maximum age of 32. All of which means it is difficult to make generalizations. It would not be a stretch to suggest, however, that the entire era of hunting blue whales in the Antarctic—from 1904 until 1966— spanned a single generation. If an individual did manage to stay alive for these 60-some years, the feat would have been more remarkable than surviving a firing squad.
Which leads us to perhaps the most high-profile blue whale mystery of all: how many are left alive? Before getting to that question, it helps to know that the Antarctic population alone was between 200,000 and 300,000 just a century ago. During the first seven decades of the 20th century, whalers killed more than 330,000 blue Lamalera is one of the few surviving outposts of traditional whaling today, but the hunters target only sperm whales. Blues are the only large baleen whales seen near the island, and they are left unharmed. "There was a legend that the blue whale once saved our ancestors from drowning in the sea," a village leader told the Jakarta Post in 2007. "So we don’t kill blue whales."5
Not until the late 17th century was the blue whale formally identified in Europe. British and Dutch whaling was in full swing during the 1600s, but blue whales were not among the catch, so naturalists had to wait for specimens to be delivered to their shores by the forces of nature. Toward the end of the century, the first recorded blue whale was served up in this fashion to Sir Robert Sibbald. In the 1680s, Sibbald was a founder of the Royal College of Physicians of Edinburgh, the Geographer Royal to King Charles II and the first professor of medicine at the university in Scotland’s capital. Sibbald also published several writings on the flora and fauna of his native country, including a 1694 work entitled Phalainologia Nova: or, observations on certain of the rarer whales recently stranded on the coast of Scotland, which contains the first published description of a blue whale:
In the month of September of the year 1692, on the south shore of the Firth of Forth, near the ancient fortress of Abercon, was cast up a male whale 78 feet long . . . It was believed that its girth exceeded 35 feet . . . In the upper jaw the whole palate was seen to be covered with black hairs, or rather bristles, which hung above the tongue, with which, at the sides, equally separated, appeared black, horny plates . . . No blowhole was present in this beast, but toward the forehead there were to be seen two large apertures approaching a pyramid in shape . . . The lateral fin was 10 feet long, 2½ feet broad where widest . . . The penis, which hung from the body not far from the navel, was 5 feet long, where thicker it was 4 feet in girth, and it gradually diminished to a very narrow extremity . . .
The tail, from that part in which it was divided into two flukes to the upper extremity, was 10 feet long; the distance between the two extremities of this (the flukes) was 18½ feet. 6
Carolus Linnaeus relied on this account by Sibbald when he created his famous system of classifying animals and plants, making it the basis for one of the four whale species he named in the 1758 edition of his Systema Naturae. For more than a century afterwards, however, the animal that would later be called the blue whale remained obscure. While European naturalists wrote a succession of books and papers on the great whales, the vast majority had never actually seen one, and their descriptions often simply repeated— one might say plagiarized—the work of those before them. There were few opportunities for even the most conscientious natural historians to examine specimens, and even well into the 19th century illustrations of whales were hilariously inaccurate, complete with fountains of water spouting from the blowholes. In Henry William Dewhurst’s The Natural History of the Order Cetacea, published in 1834, the drawing of the "broad-nosed whale"—an old name for the blue—wears a Hitlerian moustache. It is hard to know what inspired this artistic fancy—rorquals, especially young ones, do have a small number of short hairs on both the lower and upper jaw, but nothing so conspicuous. Perhaps the illustrator was influenced by the scientific term mysticete, which is from the Latin for "moustached whale"—though the reference is to the bristly baleen, not facial hair.
If Dewhurst had no first-hand knowledge of live rorquals, he did provide a detailed description of what may have been the first publicly exhibited blue whale skeleton. On November 4, 1827, he explained, some fishermen discovered an enormous dead rorqual in the North Sea and, with the combined efforts of three ships, managed to tow it to the harbour of Ostend, in what is now northern Belgium. "The appearance of a whale of such enormous dimensions created a great sensation," Dewhurst wrote, "inasmuch as those whale, albeit a dead one. Some impresarios, not content simply to mount the bones, even exhibited intact whales. In December 1880, a Massachusetts businessman named George Newton launched a tour of the midwestern United States featuring "The Prince of Whales," a 60-foot blue whale carcass. Newton was apparently able to keep the whale at least partially frozen as the Prince made its way by railroad to Chicago, Milwaukee, St. Louis, Cincinnati, Louisville, Columbus, Cleveland, Philadelphia and Buffalo. More than 100,000 people reportedly paid to see the whale—"at 25¢ for adults, 15¢ for children, orphans free"8—but when it arrived in Michigan in May 1881 the carcass was decaying too fast. Despite the valiant efforts of several Detroit butchers and an overmatched taxidermist, the Prince’s reign was over. By the time P.T. Barnum arrived in America the following spring with a smaller though less smelly animal attraction named Jumbo the Elephant, the spectacle had been long forgotten.
In the late 1960s, the American Museum of Natural History in New York attempted to build a full-sized, realistic model so people could get some idea of what a blue whale would look like in life. The few museums with blue whales at that time tended to mount them in decidedly unnatural poses—the Smithsonian’s original model, "with its flippers outstretched like stubby wings, did look a bit like a sausage coasting along in a low flight pattern."9 A team of New York craftsmen worked for more than two years on the model, forced to guess at some anatomical features that were not well understood. The 94-foot whale, weighing some 21,000 pounds, was finally unveiled on February 26, 1969, to the amazement of 35,000 visitors, breaking the museum’s attendance record. Ingeniously suspended without wires—it is attached to the roof trusses at a single, inconspicuous point—it appears to hover in mid-air, its form arching gracefully as if the animal is about to dive. (The model is even more impressive today, having undergone a makeover in 2003 to make its shape and colouring more accurate.) No doubt many of the New Yorkers who walked beneath the model that winter day According to the Oxford English Dictionary, this is the first known usage of the term blue whale. However, from the context it is not clear whether Melville’s blue whale is even meant to describe something real. Indeed, the whole chapter is written with irony and takes humorous digs at the scientific authors of the day. Melville’s knowledge of rorquals would have been second- or third-hand, but even if he was aware of a species much larger than the one featured in his novel, he may have chosen to ignore it, as the scholar Lauriat Lane Jr. explained:
Wittingly or unwittingly—the charge stands not proven— Melville had to slight the blue whale . . . Melville himself had sailed in the sperm whale fishery. To maim Captain Ahab, Melville’s moral drama demanded a very large, toothed cetacean. Ecologically, erotically, and psychoanalytically the hunt had to be for the sperm whale. Thus, epically and allegorically, the hunt for the sperm whale had to be for the largest of all whales. And Melville, wrongly, made it so.12
The OED’s second citation for "blue whale" is from the 1888 edition of the Encyclopaedia Britannica, and is unequivocally the same animal for which we use the term today. But this came 37 years after Moby-Dick, and it is during those intervening years that the name was really coined. It originated in Norway (as blåhval) shortly after the harpoon cannon was perfected by Svend Fo/yn, the father of modern whaling. Fo/yn immediately turned his new invention on the species that had previously eluded human hunters, and in 1874 a Norwegian scientist examined some of these specimens for the first time:
The whole ground color of the whale, seen at a distance, has a very distinctly bluish cast, and that in a more conspicuous manner than in any other whale with which I am acquainted. The name ‘Blue whale,’ bestowed on this species by Foyn, seems to me very suitable, and I will therefore propose that it be adopted for the species as the Norwegian common name.13
In only thirty years or so, Fo/yn and his harpoon cannon would succeed in blasting his newly named whale to near extinction in the seas off northern Norway. By the beginning of the new century, however, expeditions to the Antarctic returned with news that the Southern Ocean held more blue whales than anyone could have imagined. Melville’s "seldom seen" sulphur-bottom was about to become the target of an all-out assault.
Excerpted from Wild Blue by Dan Bortolotti.
Copyright © 2008 by Dan Bortolotti.
Published in October 2008 by St. Martin’s Press
All rights reserved. This work is protected under copyright laws and reproduction is strictly prohibited. Permission to reproduce the material in any manner or medium must be secured from the Publisher.