Leviathan. Philip Hoare

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СКАЧАТЬ of Durban in South Africa in 1969 was found with the remains of two Scymodon sharks in its belly. Since such fish are bottom dwellers feeding at three thousand metres, this was proof of the whales’ extraordinary diving abilities. Much of what we know about sperm whales was discovered by those whose primary interest was to kill them. Whales died that men might describe them.

      Nor are they easily replenished. The sperm whale has the lowest reproductive rate of any mammal–females produce single calves only once every four to six years. It is also the most sexually dimorphic cetacean: males may be twice the size of females. The sexes live apart for most of their lives, the males growing larger and all the more attractive to their potential, if fleeting, partners. This also has the benefit of maintaining the supremacy of their species: the vast distances they travel ensure that the global population of sperm whales is surprisingly genetically similar.

      Moving south to breed, males fight for the females’ favours. The distorted jaws–some even tied in knots; Moby Dick’s own mandible is described as sickle-shaped as it scythes off Ahab’s leg–that Beale saw are evidence of these ferocious but short-lived battles, as are teeth marks on the animals’ heads, backs and bellies. Although they have no territory to defend like rutting stags, whales will take bites out of each other’s blubber, ramming one another with pugnacious foreheads which in males become almost obscenely extended.

      Successful suitors mate belly to belly, with females underneath–more hominum, in Ishmael’s discreet words. Gestation lasts fifteen months; calves are nursed for at least two years, sometimes communally, and thirteen-year-olds have been known still to suckle. ‘The milk is very sweet and rich,’ says Ishmael; ‘it has been tasted by man; it might do well with strawberries.’ Lacking lips, calves take the milk into the side of their mouths as it is squirted from their mothers’ teats, a technique first identified by the surgeon Sir William Wilde, father of Oscar.

      Sperm whales have the most complex social structure of any animal other than man. Like other toothed whales, they travel together, separated by sexual maturity into reproductive and bachelor groups. Females and immature whales swim together in groups of twenty to thirty, dispersed over a wide area; they prefer warmer waters, possibly because fewer killer whales–their only natural predators–are found at such latitudes. Communal care confirms these extended bonds: when a mother dives for food, she will leave her calf–which cannot yet follow her–in the care of other females or juvenile males in a cetacean crèche. Large males have been seen gently carrying calves in their mouths, although the fact that they simultaneously exhibit extended penises probably means that this has more to do with mating than nursing.

      In their teens and twenties, young males join bachelor groups, as though entering a rite of passage. They attain maturity at nineteen (females become sexually mature as early as seven years old), but do not mate until their twenties. They travel further in search of prey; adult males roam more than forty degrees latitude north or south, forming loose concentrations spread over two hundred miles or more. Eventually these groups reduce in size until, in middle age, the males become solitary, roving as far as sub-polar seas to find new feeding grounds before returning to warmer waters to mate.

      In the interests of order, the whalers subdivided their subjects, applying human terms of trade and organization to marine mammals:

      Pods, or gams: up to twenty whales

      Schools, or shoals: twenty to fifty whales Herds, or bodies: fifty whales, or more

      Single bulls were schoolmasters, groups of females were harems, and young males, bachelor schools of ‘forty-barrel bulls’. Ishmael gives us a memorable description of a nursery into which the Pequod sails. He looks down through limpid waters, to where

      another and still stranger world met our eyes as we gazed over the side. For, suspended in those watery vaults, floated the forms of the nursing mothers of the whales…and as human infants while suckling will calmly and fixedly gaze away from the breast…even so did the young of these whales seem looking up towards us, but not at us, as if we were but a bit of Gulf-weed in their new-born sight.

      None of this, however, prevents the crew from laying into the innocent scene. It is one of the cruellest aspects of its historical fate that this most hunted of whales is built for a long life, a longevity indicated by the slow beating of its huge heart at ten times a minute; a shrew, whose heart beats one thousand times in a minute, lives for just a year. It is as if the animal’s life history had been slowed down by virtue of the millions of years its species has existed. At forty-five, a sperm whale is middle-aged, and has achieved its optimum size; like a human, it enters old age in its seventies. Females live into their eighties and perhaps to one hundred years or more, although none is known to have given birth after their forties. Rather, these matriarchs assist other females ‘in ways we do not yet understand’, as Hal Whitehead, one of the great modern experts on sperm whales, says. He calls these older females ‘sages’, raising images of elderly, grey-haired grandmothers, teaching their sons and daughters how to raise their children and passing on memories of good feeding grounds.

      Given their slow breeding and the centuries of hunting they have endured, it is a testament to their evolutionary success that the Physeter should remain so ubiquitous throughout the world’s oceans; among mammals, only killer whales and humans achieve such a cosmopolitan reach. Although they adhere to deep water, sperm whales have been seen off Long Island, almost within the city limits of New York, while others swim not far from the coast of Cornwall or Norway. These are generally lone bulls, but other whales may travel in schools of hundreds or even more, numbers ‘beyond all reasonable conception’ to Frederick Bennett. Whalers would suddenly come across huge herds of these enormous animals, like buffalo on the plain. Dr Whitehead too compares them to elephants, roaming the ocean’s savannah, with similar social structures and mutual dependencies–even the same highly modified and very useful noses.

      And as they roam the oceans, whales observe neither night nor day. Like all whales, they are voluntary breathers, and must keep half their brains awake while they sleep, during which–if dogs are anything to go by–they certainly dream. Sometimes they hang perpendicularly like bats, blowholes to the surface, dozing in a drowsy cluster after feeding. Sperm whales exhibit social skills that go far beyond the herding instinct. They enjoy the contact of their bodies, spending hours slowly rolling around one another just below the surface. ‘They seem to love to touch each other,’ says Jonathan Gordon of this underwater ballet. ‘It is not unusual to see animals gently clasping jaws.’

      Such cohesion extends to self-defence. Forever on the move, whales will swim in ranks, like soldiers on parade’, seeking safety in numbers, diving in clusters to feed, synchronizing their soundings as security against predators. Even such fiercely armed animals are vulnerable to attack from orca–more especially so in the three-dimensional hunting ground of the ocean where there is no place to hide, and where a victim can be approached from any angle. Here their only refuge is each other.

      Threatened sperm whales will stop feeding, swim to the surface, and gather to each other in a cluster. Assembled nose to nose around their calves, they form a tactical circle known as a ‘marguerite’, bodies radiating outwards like the petals of a flower. Thus they present their powerful flukes to any interlopers, protecting their young in a cetacean laager. In an alternate version, they touch flukes, heads out and jaws at the ready. Besieged whales will maintain these positions silently, unmoving. If a whale is separated from the circle, one or two of its companions will leave its safety to escort the animal back to the formation, risking their own lives as the killers take great chunks out of the sperm whales’ flesh, foraging like packs of wolves. These are, writes one naturalist, ‘“heroic” acts by almost any definition’.

      Ironically, while such techniques are successful in repelling orca, they also made the animals more susceptible to slaughter by man. ‘The females are very remarkable for attachment to their young,’ Beale observes, ‘which they may СКАЧАТЬ