How plastic bags are poisoning the planet's greatest predators: 65ft long sperm whales are being killed by human pollution

You quickly run out of superlatives when talking about whales.

They are the largest, loudest and longest-lived animals on our planet. How amazing, then, that we should still know so little about them — and that our ignorance has led these beautiful creatures into clear and present danger.



As a writer, I’ve studied whales around the world — from majestic blue whales off Sri Lanka to the playful humpbacks of Cape Cod. But it is the enigmatic sperm whale which fascinates me.

The sperm whale - at 65ft long, 'the greatest that has ever existed' - spends 90 per cent of its life in the profound depths, able to dive deeper than any other animal

It has the biggest brain of any animal — a massive 18lb to our human 3lb — yet we really have no idea what it does with it.



This magnificent predator — at 65ft long, the greatest that has ever existed — spends 90 per cent of its life in the profound depths, able to dive deeper than any other animal.



For precisely that reason, it is the least studied of all the great whales.



And of all whales, it is under the greatest threat, too — from what we humans are doing to its environment. Only now are we beginning to understand these creatures. But is it too late?



This week the results of the first Whale Symposium ever held in Britain were published in a book I co-edited.

It contains new scientific research revealing the true nature of this most mysterious ocean giant, but also the devastating impact we humans are having on them — not least because we pollute their habitat with plastic bags and other waste — and the terrible problems they face as a result.



The sperm whale is a natural submarine, a miracle of evolutionary engineering. It is actually able to change the physical shape of its body to accomplish its dives.

A sperm whale can dive down for more than a mile, to depths which would crush a human being's internal organs at a pressure of 500lb per square inch

At the surface, it will breathe deeply, like an athlete getting ready for an event. It exchanges all the carbon dioxide in its body for oxygen, storing it in its muscles.



Humans do this to a certain extent, but the whales’ muscles are far more efficient at the process, as demonstrated by their almost black colour, an indication of how supercharged they are with myoglobin, which binds the oxygen to their blood.



As it prepares to dive, the sperm whale undergoes one of nature’s most amazing transformations. Its characteristically square head is in fact an extended nose. Fifteen feet long from nostril to shoulder, it contains a massive reservoir of spermaceti oil.



This waxy oil has remarkable bio-acoustical properties. It is used to amplify the sonar clicks that echo along the animal’s head and out into the ocean.



The result is the loudest noise created by any animal — 230 decibels, as loud as a jet engine and powerful enough to be heard six miles away.



As the whale dives, its massive nose, which is plump and bulbous when at the surface, is squeezed into a narrow, hydrodynamic wedge shape — the better to allow the animal’s plunge into the abyss.



The whale then shuts down every organ in its body, except heart and brain, in order to conserve energy and oxygen.



Its lungs collapse as the animal’s ribs close in on bony hinges, lubricated by special mucus. If they did not, the increased pressure below would snap its ribcage.

Any air left in its body is confined to its nasal passages, where it is needed to generate the sonar clicks the animal uses to hunt.



Its flippers fit into its sides like an aircraft’s undercarriage. Everything is streamlined.



Finally, the whale uses the rippling muscles in its tail to jack-knife downwards with an astonishing power.



Having witnessed this feat from water-level, I can attest to its amazing dexterity. The animal is so beautifully designed that it barely leaves a ripple at the surface. Amazingly, when it reappears, it will do so at almost exactly the same point.



A sperm whale can dive down for more than a mile, to depths which would crush a human being’s internal organs at a pressure of 500lb per square inch.



In just five minutes, it can reach a depth of 500 metres, the limit at which a human diver can work.



Soon it will far exceed that, reaching 1,000m — its favoured hunting ground. We do not know exactly how the whale’s body resists such pressure. But it must be comfortable down there, since it can spend two hours underwater.



In the inky darkness, the whale hunts by using its sonar as a sweeping scan, in search of its favourite food: squid.



Their prey ranges from shoals of creatures little bigger than cuttlefish to gargantuan giant squid up to 50ft long.

By virtue of its position at the top of the marine food chain, the pollution we dump in the sea affects sperm whales more than any other creature

As they zone in on them, the whales appear to communicate in strange growls and buzzes. Are they indicating the direction and source of their food? Maybe they’re just happy at eating.



Each sperm whale must consume up to 1,000 squid a day — that’s 1,100lb or half a ton of calamari! Although it has a 10ft-long jaw studded with 42 of the biggest teeth in the animal kingdom (each up to 2ft long), it does not bite its prey.



Instead, it sucks up its food like a giant vacuum cleaner, swallowing the squid whole. We know this from the stomach contents of dissected whales.



Or, as I have seen myself in the Azores, from the loose tentacles that break off in the process and float to the surface. Unlike the whale, which decompresses as it resurfaces, a squid’s body cannot survive the rapid change in pressure. It liquifies to a gooey, soupy mess.



Occasionally, however, a sperm whale will feed at the surface. Off Kaikoura in New Zealand, where the waters run six miles deep, I watched a massive, 50ft male sperm whale at the surface.



Around it were circular patches of disturbed water — the result of the ultra-loud sonar bursts it was using to knock out yard-long kingfish — almost like a sonic gun. It is a lethal weapon unique to sperm whales, so intense that they can kill prey at a distance.



I watched as the whales’s great head erupted from the waves, a stunned fish in its huge toothed jaws. It looked as if it were triumphantly claiming its prize. But no one has ever witnessed a sperm whale feeding at depth — although that may be about to change.



Professor Hal Whitehead is one of the world’s most pre-eminent experts on this amazing species. He told me recently that new equipment currently being developed will allow scientists to attach cameras to whales and record their foraging behaviour.



Already, using high resolution digital electronic tags which monitor exact movements, speed and ocean depths, Hal and his colleagues have been able to trace much of what sperm whales get up to in the deep.



But it may be some time before we can see for ourselves the greatest battle known to nature — the mythical struggle between the sperm whale and the giant squid.



It has even been claimed that the squid will use its tentacles to smother the whale’s blow hole in an ultimately futile attempt to defeat its foe.

We humans are having a devastating impact on sperm whales - not least because we pollute their habitat with plastic bags and other waste - and the terrible problems they face as a result

For centuries man has hunted the sperm whale, principally for that precious oil in its pugnacious head. Before the discovery of mineral oil, sperm whale oil burned in street lights and oil lamps. It lubricated the machines of the Industrial Revolution.



It was even used in the NASA space missions as lubrication for space probes, since it does not freeze in sub-zero temperatures.



In 200 years we managed to reduce their population from two million to 360,000.



Luckily, most of the world no longer hunts these beautiful creatures. But now, tragically, there are new dangers to their wellbeing.



By virtue of its position at the top of the marine food chain, the pollution we dump in the sea affects sperm whales more than any other creature.



One of the greatest problems faced by any marine species is the sheer amount of plastic in the ocean, especially plastic bags, as has been highlighted by the Daily Mail’s campaign against the profligate use of them.



Dr Ruth Leeney notes in the book I co-edited, Dominion: A Whale Symposium, these bags don’t biodegrade. They break down into smaller fragments that enter the food chain — and eventually the whales’ bodies.



‘It is ironic that a plastic shopping bag, with so short a lifespan in a person’s existence, can have a powerfully negative impact elsewhere, by causing unnecessary death’, says Dr Leeney.



As my fellow editor, artist Angela Cockayne notes, a minke whale recently stranded itself on the French coast. Its stomach was clogged with 800kg of plastic, including British supermarket bags.



One problem for the sperm whale is, ironically, its awesome success. It inhabits every ocean and almost every sea, from the vast Pacific to the enclosed Mediterranean. This is because it has evolved to find the perfect feeding niche, albeit a mile below the surface of the ocean.



It is a staggering fact that sperm whales eat more squid and fish each year — 100 million tons, than the 70 million tons we humans catch and consume per annum.



The sperm whale has to eat so much to fuel its huge brain, which is highly expensive, in calorific terms, to run.



Given the size of their brains, sperm whale society is remarkably complex. Like the African elephant, it is matriarchal. So much so that females which are unrelated genetically will ‘baby-sit’ each other’s calves when they dive to feed.



The whales also travel almost inconceivable distances. Every year, male sperm whales migrate towards the poles, returning toward the equator to breed. One male may travel more than 1,000km a month.

It is a staggering fact that sperm whales eat more squid and fish each year - 100 million tons, than the 70 million tons we humans catch and consume per annum

They communicate in a complex system of Morse-code-like clicks, and each ‘clan’ has a different dialect, in the way a Yorkshire accent differs from a Devon one.



Individual animals may be miles apart but they are always in intimate contact, through their extraordinary sense of hearing.

Such supreme adaptability means that sperm whales live to great ages, at least 100 years old. Bowhead whales, their cousins, live to even greater ages — up to 300 years and perhaps even older, making them the planet’s longest living mammal.



We know this from ancient harpoons that have been found embedded in the blubber of bowheads, and which have been Carbon-14 dated to 235 years and older.

It means whales may be swimming in the sea now which were alive before Victoria ascended the throne or Captain Cook discovered Australia.



By living so long, whales are of course susceptible to diseases of old age, like humans. But they are also subject to the effect our modern habits are having on their world.



On a recent trip to the U.S. University of Southern Maine in Portland, Dr John Wise showed me new research he has been conducting into the way contaminants from the chemical industry are entering the sperm whales’ bodies.



He explained how chromium, a deadly carcinogen which induces lung cancer in humans, is released from chemical processing plants into the air.



The whales, which pass by such plants on the coast of Queensland, northern Australia on their migratory routes, absorb the chromium because they breathe so deeply at the surface.



The result is causing changes to immune systems, and fertility, creating birth defects analogous to Down’s syndrome in humans.



In another recent and tragic case, a group of seven sperm whales stranded themselves on a Mediterranean beach. They had been driven into shallow waters, possibly by military sonar exercises. There they were unable to feed on squid. And since whales get their liquid from their food, they began to dehydrate.



Then, their starving bodies began to break down fat — to deadly effect. The pollutants they’d absorbed from the ocean and had been deposited in their fat were released.



They included heavy metals such as mercury, lead and cadmium, and organochlorines like PCBs and DDTs, even fire-retardants used on modern furnishings.



In effect, the whales were poisoning themselves. Fatally weakened, they stranded themselves together on the shore, demonstrating the unswerving loyalty to each other for which their species is renowned.



And when their carcases were dissected, it came as no surprise to discover an unusual amount of plastic, including the dreaded plastic bags, in their stomachs.



What a tragic end for such magnificent animals. And what a salutary lesson for us humans.





