Leviathan. Philip Hoare

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 be frequently seen urging and assisting to escape from danger with the most unceasing care and fondness.’ If one were attacked, ‘her faithfull companions will remain around her to the last moment, or until they are wounded themselves’. This was known as ‘heaving-to’ by whalers, who capitalized on their prey’s fatal tendency to foregather when endangered, and destroyed entire schools ‘by dextrous management’. ‘They did not swim away or dive,’ wrote an observer of a twentieth-century hunt. ‘The gunner, therefore, took the whales very easily, starting with the largest one.’ As Beale adds, poignantly, ‘The attachment appears to be reciprocal on the part of the young whales, which have been seen about the ship for hours after their parents have been killed.’

      To humanize the whale oversteps boundaries; but when entire families follow a stricken relative to strand on a beach, or when a wounded female, mortally gashed by a ship’s propeller, is borne up by the shoulders of her fellow whales, it is difficult to resist the pang of emotion. They are truly gentle giants: as elephants are supposed to bolt at the sight of a mouse, so sperm whales can be faced down by a pod of militant dolphin. The appearance of a seal, or even the click of a camera, may send them scurrying. It is almost as though, as Dr Whitehead remarks, the whale sees its own habitat as a dangerous, even frightening place.

      Yet these are carnivorous animals, voracious in their appetites. They eat mostly cephalopods, but also take tuna and barracuda; entire thirty-foot sharks have been found in their bellies. And they consume in enormous proportions, taking from three to seven hundred squid a day: worldwide, sperm whales eat one hundred million metric tons of fish a year–as much as the annual catch of the entire human marine fishery.

      Diving deeper than any other mammal, we simply do not know how sperm whales behave in the ocean’s depths. We know what they eat, because we find it in their stomachs; but we don’t know how it gets there. Sound is certainly important to their sustenance. Although they lack a voice box–as Thomas Beale noted, ‘The sperm whale is one of the most noiseless of marine animals…it is well known among the most experienced whalers, that they never produce any nasal or vocal sounds whatever, except a trifling hissing at the time of the expiation of the spout’–the whale possesses the largest sound system of any animal, using one-third of its body to create the loud clicks that it constantly emits when hunting. The whale’s oversized nose is in fact a huge and highly efficient squid-finder.

      As bats send out sonar to find flying insects, so sperm whales send out similar, if rather louder, pulses to locate their prey. Their characteristic clicks are produced by the expansion and contraction of ‘blisters’ on their nasal sacs. It is a remarkably complicated sequence, as Dr Whitehead explains. Two nasal passages run from the external blowhole, the left and the right. The left runs directly to the lungs, but the right passes through a distal air sac via a kind of valve known as the museau du singe, or ‘monkey’s muzzle’.

      Sound is initially generated by air being forced through this valve–not unlike the clicks you can make by hitting the roof of your mouth with your tongue–then passes through the animal’s upper spermaceti organ or ‘case’ before bouncing off another, frontal air sac set at the back of the skull–a bony sound mirror, in effect. This is then redirected and broadcast through a series of acoustic lenses in the ‘junk’, the lower oil-containing organ in the whale’s head. Thus the strange mechanism of the sperm whale’s nose acts as a living amplifier. Some sound also bounces back and forth along the case, producing a second pulse. As this inter-pulse interval is equal to the length of the case, the actual sound created by the whale–the pulses between its clicks–may be a measurement of its physical size; one may tell the length of the animal from the inter-pulse interval, just as the bigger the whale and its head, the more powerful its clicks. Breeding males may size each other up from their clicks, and can tell each other’s sex by the same sound; they are as much a tribal definer as the click speech of the Xhosa of South Africa.

      The clicks, which can be heard for many miles, are important for navigation and communication. They extend the whale’s sensory map far beyond its own body, and their speed and variation change from group to group, as an English dialect changes from Yorkshire to Hampshire. This allows individual whales to identify and communicate with members of their family, evenas they use the earth’s magnetic fields to map out their subaquatic terrain, the peaks and valleys of the oceanic abyss in which they are effortlessly at home. And as they dive–often in an informal group–they use their clicks to locate and scan, with extraordinary precision, the distance, presence and nature of their prey. It is thought that a whale can ‘see’ into its prey, diagnosing it–even to the extent that it can tell if it is pregnant. The returning clicks are ‘heard’ through the dense, hard jaw bone–the same bone from which Ahab’s false leg is carved–and which acts as a listening device in its own right, conducting sound through bioacoustical oils directly to its eardrums. The whale’s external ear is largely useless; the animal hears through its body itself.

      The deeper it dives, the more effective the whale’s senses are, away from the chatter and interference of the world above. A sperm whale can create a two-hundred-decibel boom able to travel one hundred miles along the ‘sofar’ channel, a layer of deep water that readily conducts noise. It seems strange that such a physically enormous creature should rely on something so intangible; but bull sperm whales, by virtue of their larger heads, generate sounds so powerful that they may stun or even kill their prey. These directional acoustic bursts, focused through their foreheads and likened to gunshots, are the equivalent, as one writer notes, of the whale killing its quarry by shouting very loudly at it.

      In their own researches, Soviet scientists, whose nation’s enthusiastic