Kim Westerskov

Humpback

Almost driven to extinction for their meat, oil, bone and baleen, humpback whales are making a comeback, not only in the seas, but in human consciousness. With their haunting songs and evidence of culture—even language—they are now embraced as mysterious long-neglected kin, perhaps a seat of wisdom deeper and more enduring than our own; icons of oceans too long abused.

Written by       Photographed by Kim Westerskov

It rose out of the sea, 45 tonnes of military-grey missile in vertical ascent. Once airborne, it stopped, hung motionless for a second, then crashed back into the ocean.

The image was familiar. It can be seen in picture books and art shops and on children’s bedroom walls all over the world. What wasn’t recognisable was the sound of a kid squealing on a ferris wheel that was coming from my mouth. I had just seen my first breaching whale.

“Was the tail completely out of the water?” the experts interrogated me afterwards, in the house where the mem­bers of the South Pacific Humpback Whale Project re­search team were staying. “Are you sure?” A hint of envy in their tone underscored the unfairness of beginner’s luck. On my first outing to look for humpback whales in the northern Vava’u group of the Tongan islands I had witnessed not only a breach, but a full breach, something dedicated whale watchers can spend hundred of hours hoping for, but never see.

To describe the sheer exhilaration of watching an ani­mal that weighs as much as two fully laden concrete trucks shoot out of the water until its head is 20 metres above the surface is impossible, every phrase a tired one when com­pared to this explosion of energy. Then again, everything about whales is big. Statistics for blue whales, even larger than the 16-metre humpback, are almost beyond compre­hension. The tongue of an adult blue whale weighs as much as an elephant. The heart weighs two tonnes, and each beat shifts more than 200 litres of blood. A child could climb through the aorta where it leaves the heart, and even average arteries are the size of domestic stormwater pipes. Infant blue whales put on more than a hundred kilograms per day, consuming a daily ration of 450 litres of very rich milk to do so.

Impressive as these facts are—rattled off in a paragraph as if they had been casually plucked from a cornucopia of whale statistics—they mask a vast ignorance of the ways of whales. We may scoff at uninformed early whalers who named right whales simply because they floated when killed, and were therefore the “right” whale to harpoon, yet the sum of human knowledge of cetaceans—whales and their relatives the dolphins—is hardly a credit to 200 years of scientific investigation.

Whales may have the largest brains in the animal king­dom, but our understanding of what those brains are used for is abysmally small.

Humpbacks are baleen whales belonging to the group Mysticeti—whales which feed by straining small fish and crustaceans from seawater through hundreds of springy plates in their mouths made from keratin, the stuff of hair and fingernails. Blue, fin, sei and right whales are others which belong to this group, all of which have paired blow­holes like nostrils. Sperm whales, dolphins and orca differ in that they have teeth and a single blowhole; they are placed in a separate group, the Odontoceti.

The South Pacific Humpback Whale Project was set up two years ago by a group of scientists who wanted to find an answer to a fundamental question of whale ecol­ogy: what has happened to the humpback whale popula­tion that used to migrate close to our coastline on its way to and from Antarctica—the whales decimated by pelagic whaling ships and shore stations for half this century?

Two centuries ago, humpback whales were the most widely distributed of all the great whales, and were found throughout all the world’s oceans. Today only remnants remain. Nevertheless, they still undertake their enormous annual migrations from summer feeding grounds in polar waters to winter breeding grounds in the tropics.

The humpback’s scientific name (Megaptera novaeangliae or “big-winged New Englander”) refers not only to the enormous pectoral flipper (the largest append­age in the animal kingdom, up to 28 per cent of the body length), but remembers the American whalers who were the first to exploit the species commercially. Their com­mon name came about because these whales arch their backs sharply when they dive, but it is an unfortunate name for a graceful animal.

Sadly, it is a grace few New Zealanders will ever see. Sightings in our waters are rare, despite the fact that the animals were given full protection from whaling in the 1960s.

“The local population is not recovering,” says Mike Donoghue, marine mammals officer with the Department of Conservation. “This is in marked contrast to the situa­tion in Australia, where the number of humpbacks appears to be increasing rapidly, by an estimated eight per cent per annum, on both the east and west coasts.”

Donoghue has been active in the conservation of whales since 1978, when he helped write the Greenpeace submis­sion for the Frost Enquiry into Whales and Whaling in Australia. In 1979, he helped to expose an illegal whaling operation by the Japanese in Chile.

Together with molecular ecologist Scott Baker and bioacousticians David Helweg and Peter Jenkins, he is working to conserve and protect humpback populations in the South Pacific.

North American Scott Baker first saw dolphins in the Gulf of Mexico, where his family holidayed when he was a child, and has been fascinated with them ever since. In the mid-1970s, he studied bottlenose dolphins. Later, while in Hawaii, he turned his attention to the humpback whale. “I realised that little as we knew about dolphins, we knew even less about whales,” he says. Baker is a world leader in the use of molecular genetic techniques for the analysis of whale populations.

Molecular genetic analysis of DNA is such a powerful tool that from a gram or two of meat you can determine the sex of the specimen, the species of whale, and perhaps the part of the world the whale inhabited, even after it has been marinated, shrink-wrapped and put on the super­market shelf. Baker’s analysis of whale meat on the Japanese market a couple of years ago turned up some protected species freely on sale, and caused considerable embarrassment for the Japanese government.

At the time, the establishment of the Southern Whale Sanctuary was in the balance, and Donoghue believes Baker’s findings helped persuade some countries to vote in favour of the sanctuary.

“What we are doing,” explains Baker, “is bringing the power of these sophisticated new biomedical research techniques to aid in the study and conservation of wild animals.”

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It is September, before the full torpid heat of summer has set in. Accompanied by a team of volun­teers from all over the world, Baker, Donoghue and Helweg have been spending long days at sea in a small inflatable boat obtaining tissue samples for Baker to analyse, and ascertaining the state of the whales in the waters surrounding Vava’u.

There has been surprisingly little research on whales in the South Pacific, and much of what has been done has come from whalers and commercial interests. There is no absolute certainty about humpback migration routes, al­though the whales are remarkably regular in their patterns of movement, staying close to the coast and passing the same spot at virtually the same time each year at a stately three to five knots. (Related whales such as the blue, fin and minke swim two or three times faster.)

No one has much of an idea about the true size of the South Pacific humpback population. Prior to the onset of commercial whaling in the early 1900s, it is estimated that more than 100,000 humpbacks spouted in the waters of the Southern Hemisphere. When the International Whal­ing Commission banned the taking of humpback whales in 1963, only 3000 were thought to remain—an estimate which turned out to be based on misleading data. In 1994, news was released that the Soviet Union had ignored the moratorium and had been poaching humpbacks with aban­don. Russian scientists revealed that 48,000 humpbacks were killed in this mammoth illegal slaughter. Little won­der some populations have been slow to recover.

The researchers’ boat, the Kohola (Hawaiian for whale), can only comfortably take four people, so much of my time is spent on the deck of one-time advertising executive turned whale-watch operator Allan Bowe’s larger, more powerful vessel.

We are on our third day out when we come across five whales indulging in what looks like energetic play just outside the entrance to the lagoon of the island of Hunga. They half-breach and slap their tails repeatedly against the water with a thrashing sound. Bowe believes them to be a group of young males competing to escort a female.

The whales stay in the vicinity of our boat for about an hour, constantly surfacing, their humped backs giving them a serpentine appearance as they appear and reappear in what is known as a round-out, fluking their tails up high before each dive. One whale is distinguished by circular white marks on its side: the teeth marks of a cookie-cutter shark which has taken a small chunk out of the whale, leaving behind its serrated calling card.

Several times two whales come close to the boat and surface, and on one occasion they dive under the hull on one side and come up on the other. Their play becomes more boisterous. They fluke up one last time, and when they next blow they have headed well out to sea. The only evidence that they have ever been there is a series of flat patches in the water, like the footprints of a giant. Bowe radios the Kohola to give them the direction the whales are travelling.

“You wouldn’t have recognised them by the time we caught up with them,” Donoghue says, when we are back on shore. “Things had got more serious. They were tail-thrashing, pectoral-slapping, and generally bloodying each other.”

Normally the Tongan whales are seen in groups of three: mother, calf and male escort. The fact that there was no calf in the Hunga lagoon pod we observed sug­gested that members of this group were competing for the position of primary escort to a female.

The winter months are the mating season for hump­backs. They come each year from their feeding grounds near Antarctica to the tropical waters around Vava’u to mate and give birth (pregnancies last 11 months), although those with new calves often do not mate until the follow­ing year.

Mating itself is thought to be rapid. The only eyewit­ness account (unconfirmed) has them belly to belly, the front halves of their bodies vertical and out of the water.

During their sojourn in the tropics, the humpbacks apparently fast. “They don’t feed for months—though whether it’s six months or only three months, we don’t know,” Baker observes. “Their minds seem to be entirely on reproduction.”

The whale’s blubber—a thick fatty layer beneath the skin, once prized by whalers for its high oil content, and traditionally thought of as the whale’s insulation—prob­ably serves as a food reserve to sustain the whale during its long migrations and its stay in warm latitudes, and has little to do with keeping the whale warm.

In reality, keeping warm—even in cold Antarctic wa­ter—is not a problem for whales, on account of their size. All mammals generate heat in their body mass and lose it through their skin. Big mammals have less surface area relative to their volume than do small mammals, and so lose heat at a slower rate. For example, a mouse’s surface­to-volume ratio is 175 times greater than a whale’s, mean­ing that it is much harder for a mouse to stay warm than it is for a whale. Staying cool in the tropics is likely to be more of a problem for humpbacks than keeping warm in the Antarctic.

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Why do humpbacks migrate? Like many facets of whale biology, the answer to the question is uncertain. It was once thought that baby whales wouldn’t survive the cold of polar wa­ters, but in fact they are amply insulated. Probably the calm of tropical seas is more significant than their warmth to a calf learning to breathe.

Writes Roger Payne, one of the world’s foremost whale experts, in Among Whales; “I have witnessed humpback whales trying to breathe in thirty-foot seas created by sixty knots of wind (just barely a winter storm) when there was no definite line of demarcation between air and water but a continuum of spray as the surface of the sea was whipped into a frenzy. The way the whales avoided accidentally inhaling this half-air, half-water interface was by waiting until the steepest face of a major wave had formed and then grabbing a breath while launching themselves out through it horizontally and then crashing back into the trough of the wave. They then expelled their breath and grabbed the next inhalation so forcefully that the sounds of their breaths were clearly audible above the shrieking of the wind. It remains in my mind the most spectacular thing that I have ever witnessed in all my time at sea . . . I suspect that a calf [there were none on this occasion] might well have been in deep trouble had it mistimed its emergences as it tried to breathe.”

Despite their size (a newborn humpback weighs 2.5 tonnes and is four metres long), newborn whales are ba­bies, and have to learn to breathe, swim and suck milk from their mother.

Unlike almost all other mammals, whales are born tail first, and because they have no air in their lungs, tend to sink. The mother catches her newborn infant on a flipper or her snout, and nudges it gently towards the surface where it takes its first breath within seconds of birth. After about 30 minutes it can swim adequately. Other female whales (midwives?) swim with the mother during the hour­long labour and may assist the calf after it is born. For whales there is no nest or den, and the baby needs con­stant attention.

The mother’s nipples rest in streamlined grooves on either side of the genital slit towards the tail. In front of the nipples is a pair of mammary glands, each in hump­backs being close to two metres long and half a metre wide. Feeding takes place close to the sea surface, and the baby catches the nipple from behind. Powerful muscles around the mammary gland squirt the milk into the baby’s mouth. Whalers have noted that the milk would shoot a couple of metres from a whale on the deck of a boat.

Compared with cow’s milk, whale milk is an extraordi­narily rich food. The fat content is ten times higher (35 per cent), and the protein level double that in the bovine product, though milk sugar is very low. This cream is converted to body mass at a very efficient pace. The 40 kg of milk the infant humpback ingests each day produces an increase in weight that equates to more than a kilogram per hour.

Young begin to wean when they reach the krill-rich waters of the Antarctic.

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The kohola hurtles across tile water. At its prow, researcher Mark Brabyn gazes intently ahead of him, hands gripping a crossbow. Images of captain Ahab, the harpoon, the bloodstained water spring to mind. The chase is on, and as we follow in our larger boat I am suddenly gripped by just how deeply this dark imagery is embedded in my subconscious. Although I know that Brabyn is only firing a dart so small that the humpback will probably not even feel it, I wonder whether the whales also could have some kind of collective memory of the hunt.

Ahead of the Kohola by some 30 metres, the animal blows and surfaces. Brabyn fires, misses, and the dart skims off the water. The whale submerges. Again the boat races across the water. Another blow. He fires. A hit. The tiny dart rebounds from the whale and lies in the water awaiting retrieval.

Whale biopsies are a touchy issue. Even though the dart is only a couple of centimetres long, sterilised and coated with an antibiotic, Baker and Donoghue are sensi­tive to anything that can cause the animal discomfort of any kind, and so the reaction of each darted whale is recorded.

“I can honestly say from our experiences here that the whales very rarely have any agitated reaction,” says Donoghue. “After all, we are taking a tiny sliver of skin and blubber about the size of my thumbnail from an animal that weighs 45 tonnes.”

Such samples from a dozen or so whales can give insights into the make-up of a whole population. As well as determining each whale’s sex and its genetic relation­ship to others in the group, scientists can also work out relationships between whales in Tonga and those else­where in the South Pacific and the Southern Sanctuary.

As if to clinch the argument, Donoghue points out that the tiny biopsies provide as much information for conser­vation and management of whales as the Japanese obtain from their controversial “research whaling,” where the whale is killed.

As well as providing a skin sample, biopsies sometimes include a small amount of blubber, enabling an assessment of levels of ocean pollution, since most of the dangerous contaminants accumulate in fatty tissue such as blubber.

“In my mind, the biggest danger for humpbacks, as we go into the next century, is going to be industrial chemi­cals in the sea, most of which come from the Northern Hemisphere. These chemicals build up in whales’ bodies and can ultimately affect their fertility rate and their im­mune systems,” Donoghue warns.

Whale skin is extraordinarily fragile and fast growing. Cell division in whale skin can be up to 290 times faster than in human skin. Rapid sloughing off is the corollary to this fast growth, and may play a role in the whale’s peren­nial battle to out-manoeuvre its small enemy, the barnacle. Coronula barnacles grow only on whales, and, as with ships, can severely reduce the whale’s mobility. In one instance, four hundred kilograms of barnacles were har­vested from the head of a single humpback.

Some biologists have suggested that the barnacles might not fare too well in the tropics, so migration could repre­sent an annual clean-up. Others wonder whether barna­cles serve as weapons for male humpbacks: studs and knuckledusters with which to wound an opponent. Cer­tainly, they are concentrated on the head, tail fluke edges and flippers—the humpback’s main weapons.

Skin tissue samples go back to Scott Baker’s laboratory at Auckland University for analysis. Baker is particularly interested in a small circular piece of DNA known as mitochondrial DNA which is found in every cell. “There’s a saying,” Baker laughs, “that in life nothing is certain but death, taxes and maternity. The DNA contained in the mitochondria is a direct copy of our mother’s DNA, and her mother’s DNA before that, all the way back through time, except for mutational changes. It is these small, infrequent mutational changes that are important in re­constructing maternal family trees.”

Baker’s objectives include examining the genetic differ­ences between the Tongan whales and those of Eastern and Western Australia. All three populations are thought to stay separate, but mitochondrial DNA will reveal for certain how stable the whale’s migratory destinations are.

Another weapon in the scientists’ arsenal is the hydrophone—an “ear in the sea”—which is used to deter­mine where the humpbacks go and who they meet on the way. It is also a listening post for one of the sea’s deepest mysteries, whalesong.

“Listen to this! We just got the best song we’ve re­corded yet!” A sunburnt and exhausted researcher is stand­ing in the living room of a volunteer’s house. Everyone eagerly gathers around the cassette player as the sounds made famous by musicians like Judy Collins begin. Writer Diane Ackerman has described the music as “great boom­ing ragas of creaking and moaning and seat-shaking bass.”

Whalesong, bioacoustics expert David Helweg explains, is not like human language, but can be compared to the most complicated of birdsongs. Humpbacks have the most complex vocalisations of all the whale species.

Although it is not a language, there are what can be described as dialects, and the dialects define from which group the animal hails. “You could say that Tongan whales have a Tongan dialect, and Eastern Australian whales have an Eastern Australian dialect,” he says.

Within these dialects there is a sort of whalesong “top of the pops.” Whalesong is learned, and the themes change, with singers quickly learning songs from other singers. “So if a whale appears in Tongan waters singing Eastern Australian songs, you can tell that there has been some contact between the breeding populations,” Helweg explains.

Only the male humpbacks sing, and then only during the mating season on the breeding grounds. Best guess is that the singing is to woo prospective mates, but it could be to intimidate other males, or perhaps to keep aspiring breeders suitably spaced.

In Hawaii, Helweg has found that singing humpbacks tend to remain 6 to 10 km apart. Whale breeding seems to bear some resemblance to lek breeding in certain species of birds, in which males mount individual song or dance routines in particular territories, and breeding females choose a partner from among the suitors. Kakapo are lek breeders—when there are any females to breed with.

Since all the males within a single humpback popula­tion sing the same basic song, it must be style rather than content that appeals to the females.

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We are about twelve miles south of Hunga in a rough sea, ready to chuck it all in and go home when we see two blows in the distance. As we head in the direction of the spouts, two whales come out of nowhere and leap out of the water together in a perfect double breach only 20 metres in front of the boat. This marks the start of a display of behaviour that would be the envy of any Olympic synchronised swimming team. The two swim together, rounding-out of the water side by side. One lifts its huge pectoral and waves it in the air in a giant leviathan saluta­tion. The other returns the salute and they swim on, each one slapping its pectoral on the water in perfect timing.

They are immersed in their world, and only appear to show an awareness of ours when one of them lifts its gigantic tail and slaps the water 12 times without pause, creating a deafening sound. Donoghue and Mick McIntyre, from the Australian organisation Whales Alive, discuss the meaning of this behaviour. They agree that it could be a show of aggression, a signal that our boat is trespassing on the whales’ territory.

McIntyre is photographing every slap as part of the team’s work is to visually record the tail flukes of as many whales as possible. Each animal has a unique black and white pattern on the underside of its tail—a “fingerprint” by which it can be identified. Using these identification marks, scientists can see how many whales are present in Tongan waters each year (35 individuals were identified in 1995; no one is sure of the total population size), how often each whale is resighted, the frequency of calf pro­duction and whether the same whales are returning yearly.

One of the whales begins a barrel roll, a gigantic rota­tion which exposes the white underside. In the Northern Hemisphere, the bodies of most humpbacks are predominantly black, but in the Southern Hemisphere they are white underneath, a change in pigmentation developed over thousands of years that equates to a racial or ethnic difference.

There is something submissive in the barrel roll—like a kitten wanting to have its stomach rubbed—which convinces me that we are watching two animals in a courting ritual. The temptation to anthropomorphise whales is strong, the desire to relate them to ourselves endlessly appealing.

“We see in them something kindred with terrestrial mammals,” agrees Baker. “They give birth to live young, nurse them with milk, probably develop long-term associations, and live for 50 years. But they are also so differ­ent, so alien, so large for one thing. They have this totally different history of adapting to a marine environment for millions of years, and I think that fascinates us. It certainly fascinates me.”

The Tongans, who learned whaling from European whalers and carried out subsistence whaling until 1979, when it was outlawed by the King, share this fascination. Stories about whales are common throughout Polynesia, and a cultural psychologist, Verna Amante-Helweg, is part of the team investigating the cultural significance of the whales through the collection of oral history.

A group of us are sitting on the verandah of the re­searchers’ house drinking kava with the landlord, Pota, the local equivalent of the mayor, and some of his family. Kava ceremonies are a time when knowledge is passed on. The old men become increasingly mellow, singing the songs and telling stories from their youth.

Pota tells us the story of the whale, the turtle, the pig and the worm. Once they all lived together, but the worm became lost. The whale was sent to comb the seas, the turtle to scan the ocean floor, while the pig searched for it on earth. June and July are the traditional time of the yam harvest, and the worm is often cut in half by the digging, so the whale and the turtle came close to shore to try and save their brother. This is one Tongan explanation as to why the whales come close to shore each year during this time.

Amante-Helweg has found that many villagers are una­ware that the whale is a mammal, and think that when they are not close inshore they are living between Samoa and Tonga. They also do not appreciate that the whales sing, since sound does not travel well from water to air.

When I was last in Vava’u, five years ago, I interviewed an old whaler in his village on Hunga, the island where most of the whalers lived. They kept their boats ready in the lagoon, and when a whale was sighted they would speed out from the entrance.

The old man showed me the remains of a 28-foot whaling craft and a tatty length of rope that had been attached to his harpoon. He regaled me with tales of boats crushed against reefs after being towed miles at sea behind maddened gargantuans, his nine crew members singing to ward off their fear. But his face had been solemn when he told of killing a mother and towing the body into port at Neiafu, ironically the same wharf from which the Kohola now leaves. All the way the baby stayed close to the dead mother, lowing mournfully. Although he knew it could not survive, he could not bring himself to kill it.

Often, though, the whalers would harpoon the calf first, thus guaranteeing the capture of the mother. Whale meat was a useful source of protein for the islanders in times past.

As a young man in the 1960s, Ika Fulivai was a whaler living on Hunga. He, too, tells stories of the cheapness and delicious flavour of whale meat, the danger and ex­citement of the kill, but also makes it apparent that it is the relationship of mother and calf that distinguishes the whale from other “fish.”

“How much and how deep, the love is like a human,” he explains in softly fractured English before embarking on a grisly illustration of this bond. They had speared a mother, when her calf came up to the boat, so they speared it also. The mother came at once to her injured calf’s aid and in her efforts to lift it to the surface smashed their boat to pieces. The whalers were forced to swim the six miles to shore.

There is a myriad of island whaling stories. Allan Bowe tells of a local fisherman who, only two months earlier, had bought a new rope for his anchor—a considerable expense for a local in a cash-poor economy. A whale had lifted his anchor and towed the fisherman, who had his six-year-old son on board, for 12 miles before oncoming darkness persuaded him that discretion was the better part of valour, and he cut the precious rope.

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We are on our way to check out the entrance to the lagoon at Hunga when Allan’s Tongan crew member Nusa alerts us to two blows in the distance. Nusa, whose talent for spot­ting whales is legendary, thinks it’s a mother and calf. One blow is smaller, and they are blowing every few minutes.

Female whales nurture their young with an assiduous­ness and patience that rivals (or exceeds) that of humans. They warn the calves of danger, draw them away by tuck­ing them beneath a protective flipper, position themselves between the calf and the threat and support dead or dying young for days. In return, the calves pester their mothers as badly as any toddler.

Philippe Cousteau (quoted in Whales by Jacques Cousteau) noted “The young of right whales are extremely boisterous. A calf will constantly pester its mother for attention, even if she is resting. It darts about, wriggling up onto her back five, six, ten times in a row. It pokes its snout into her belly or jaws. It slides off her tail, much to its amusement. It covers her blowhole with its tail. It races about its mother’s body like a wild puppy . . . When the little brat goes too far, she simply rolls over on her back, catches the calf with one of her flippers, and holds it close until it calms down.”

Allan has a new photographer, a dentist from San Fran­cisco, on board. We race over. The mother, calf and an escort are close to a perpendicular rock wall. The dentist is tense. He has an impressive array of photographic equip­ment, but has never before had the opportunity to use it in circumstances like this.

Allan herds the whales with his boat, but keeps his distance, wary of harassing the mother and calf. The den­tist dives from the back of the boat and snorkels frantically in the direction of the whales. He cannot use an aqualung, as the bubbles deter the whales, who, it is believed, inter­pret them as a sign of aggression.

At times, humpbacks use bubbles to trap young fish or shrimp. Swimming in a spiral, they release air which forms a cylindrical curtain of rising bubbles. Fish, which nor­mally encounter bubbles only in breaking surf, refuse to swim through the curtain. The whale, mouth agape, swims up through the cylinder and swallows its prey, trapped against the surface. Pairs or groups of humpbacks have been found cooperating in casting larger bubble nets where food is present in cafeteria quantities.

Human swimmers need not fear. Despite their 45-tonne bulk, humpbacks are toothless, and feed mainly on plank­ton, consuming up to two tonnes of krill and small fish per day when in polar waters.

Humpbacks can take in some 10,000 litres of water in a single gulp. This water is held in a cavity that expands to become an enormous cave, extending down the underside of the whale almost two thirds of the way to the tail, and lying between the surface blubber and underlying body wall. Pleats in the blubber enable the whale’s “throat” to expand enormously, like a piano accordion.

Muscles in the tongue are contracted to squeeze the water back out of the mouth, through a curtain of baleen attached to the upper jaw. Krill and other prey are filtered out by the baleen and swallowed whole.

The mouth, which can open to more than 90 degrees, is big enough to engulf a me­dium-sized car. Roger Payne records the re­markable story of a friend of his who was studying humpbacks in Alaska, when a humpback rose beneath his boat. “The next thing he knew he and the boat were inside its widely opened mouth, a situation that only lasted for a second as the whale was appar­ently as surprised as he and instantly backed off. But he observed that when his Zodiac was in the whale’s mouth it was not grounded on the whale’s jaws but was floating freely, with water under its keel.”

The dentist clambers back on to the boat intact. He has bagged his shot, an image of three whales stacked on top of each other, with the mother at the bottom, her baby resting above her and the male making up the top deck—a sort of protective sandwich.

The dentist is aware how lucky he is to have observed, let alone photographed, this family moment. In almost every other hump­back whale-watching operation in the world, swimming with the animals is forbidden. Tonga, as yet, has no such regulations, and swimming with the animals is a controver­sial subject amongst conservationists.

It’s a matter that is ultimately up to the Tongan government, and Donoghue is aware how necessary it is for Tonga to see the eco­nomic benefits of conserving whales. “We know that some Tongans yearn for the good old days of whaling,” says Donoghue. He mentions a Tongan tourist operator who only last year took a submission to cabinet to begin a commercial whaling operation. The proposal was refused. The King is known to have a personal interest in the whales’ conservation, and doubtless the huge commercial success of whale-watching globally, which in 1994 was worth in excess of half a billion US dollars, helps confirm his decision to ban whal­ing, as does the knowledge that Tonga has the most popu­lar species for a whale-watch industry. The humpback’s habit of migrating close to the coastline, the predictability of the times of its migration patterns and its spectacular surface behaviour ensures any country with humpbacks a viable whale-watch enterprise.

One of the main concerns for conservationists is the effect of boat noise on whale behaviour. On one hand, the sound of a motor lets the whale know where the vessel is, and it can orientate itself accordingly. On the other, whales respond dramatically to sudden noise.

“The worst thing about noise and whales is the possi­bility of separating a mother from a calf. That’s what underlies the concerns of anyone who has ever studied humpback whales in any of their breeding areas where there is a tourist industry,” Donoghue explains. “When you are dealing with an endangered species, where only a small number of the existing population are breeding females, and those breeding females only breed once every two or three years, it is essential that every effort is made to ensure mothers and calves are not disturbed. The issue is not really people in the water with whales, but the vessels carrying the people to the whales.”

Whale-watching operators believe there are ways that noise can be reduced in the water, while at the same time providing a good safe service for the paying passenger. In the Kaikoura sperm whale-watching industry, there has been a trend away from noisy outboards to inboard mo­tors with airborne exhausts, and from propellers to jet units that are much quieter.

Yachts would seem to be an obvious solution (one oper­ates in Tonga for whale-watch charter) since, even when motoring, they produce little water noise. Donoghue is providing input to the South Pacific Regional Environ­ment Programme on ways in which whale-watching can be responsibly managed in the South Pacific.

Soon the whales will begin their long migration back to their feeding grounds in Antarctica, the mothers and ba­bies leaving last so the calves can spend longer in the mild waters.

I am left with the feeling that time has collapsed upon itself, and that I have had a glimpse of the world as it used to be, when the ocean was a totally different place and when perhaps tens of thousands of these animals plied New Zealand waters.

But is the South Pacific Humpback project worth the effort, I wonder. Months of work, thousands of dollars’ worth of fuel and boat hire, all for a handful of whales.

Donoghue has the last word: “A number of biologists criticise the fixation on big flagship species, but the reality is that if you can’t save the whales, you don’t have much chance of saving the lesser spotted rail—and all the much smaller animals that are just as vital to the ecological balance of the planet.

“Unless we can guarantee total protection for these impressive animals that have suffered so much in the last 200 years, how can we hope to focus public attention and concern on safeguarding the myriad less spectacular but equally important species of the world?”

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