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Global Warming Issues & Human Impact on the Ocean

"Climate change is as big a threat to people and the planet as international terrorism"

Mike Childs - Friends of the Earth campaigns director

Antarctic ice sheet

© Australian Antarctic
Division 2002

Evidence of climate change is no longer confined to scientific studies: we are frequently witnessing temperatures reach record highs and reports of freak weather conditions are becoming more common. The quote above provides an idea of how climate change should be viewed, yet for many countries it is not high up on the political agenda. Here at dive site directory we are concerned about the effect that climate change will have on our lives above and below water. This section aims to provide readers with an overview of what is happening to our planet and the changes we can expect to see to marine ecosystems if global warming and over fishing continue it their present levels. We do not want to see a reduction in the number and variety of marine creatures at the dive sites we visit; we want to keep on delighting in the amazing sights the underwater world has to offer. The facts do not make for enjoyable reading, but perhaps the depressing news may shake people into considering their lifestyles and the impact they have on the planet so that together we might begin to make a small difference.

We welcome any discussion about what is written here. To the best of our knowledge the content of this page is correct, although if you believe we have got any information wrong please let us know. If you have any comments or views on this article, please send them through!


Easy ways to help:

  • Turn off your TV rather than leaving it on standby
  • Use energy saving light bulbs
  • Improve your homes insulation
  • Buy class 'A' kitchen appliances

What is Global Warming?

Nowadays the term 'Global Warming' is a household phrase. It is something we are reminded of occasionally in news bulletins reporting on the decline of a habitat, or freak weather conditions. But what can we actually understand about the phenomenon, and more importantly, how does it stand to affect us in the near future? Does it mean the end of our seas as we know them and will creatures that live in them struggle to survive in adverse conditions? To answer these questions we'll have to take a brief look at the science and try to comprehend the reasons why scientists think our planet is getting hotter.

Global warming is the result of the build up of greenhouse gases, such as carbon dioxide and methane, in the atmosphere. These gases reflect the suns rays back down to Earth's surface rather than letting them escape back into space as they would normally, heating the planet as a consequence. We need to have a certain quantity of these gases in the atmosphere otherwise our planet would become a frozen desert. However, too high a volume and the planet keeps heating up, ultimately causing ice caps to melt and barren wastelands to form where there would have once been habitable terrain.

Records of the UK's weather patterns date back to 1861. These that show our climate is warming by about 0.2°C over each passing decade. However, scientists don't like to look at what in geological terms is very short period in the Earth's history, so they research into other areas that can provide us with a record of past climate. They use tree rings and ice cores to study the more recent past, and to look back millions of years into history they study the rocks that lie around us. Each year, trees grow outwards by a small amount. As seasons pass and temperatures alter, the amount trees grow by also changes. On a particularly cold year, a tree will not grow very much so the ring will be small. On a year that has conditions more favoured by the trees, it will grow more. So looking at a cross-section through a trees trunk, scientists can accurately tell what the climate has been like throughout the trees lifespan. Ice cores work in a similar manner, storing gas bubbles in their layers that contain vital information about the composition of the atmosphere when the bubble formed.

Tree rings and ice cores show that over the past two million years ago there have been twenty glacial advances and retreats - that is to say there have been periods of time lasting hundreds of years at a time where much of the planets water has been locked as ice. This cycle is believed to continue indefinitely until some unknown factor causes the climate to warm up and become 'post-glacial'. It is not known whether we are now in an interglacial (the last glacial period ended about one thousand years ago) or if we are post-glacial, but records show significant warming in recent history.

Huge differences in the climate of the past compared to ours today, combined with the fact that climate is such a difficult thing to model (due to all the many small factors that can cause unknown large-scale impacts) cause a few scientists to wonder if global warming is an issue at all. For example, if there is a big volcanic eruption somewhere on the planet and lots of ash is pumped into the upper layers of the atmosphere, global warming can be temporarily reversed. The dust prevents the suns rays penetrating through the atmosphere as easily causing global temperatures to fall by one or two degrees centigrade. But debates aside, the fact remains that over the last fifty years global temperatures have been on the increase and they are at their highest for at least the past thousand years. Many believe that the human race is largely liable for this, due to activities such as burning fossil fuels that lead to large amounts of carbon dioxide being released into the atmosphere. Even if the planet would have been warming up regardless of man's intervention, there is no getting away from the fact that the greenhouse gases we produce are adding to the problem. If this warming trend continues, it is going to destroy many habitats and species are going to have to adapt if they want to survive - it is not an issue we can ignore for much longer.

The National Oceanic and Atmospheric Administration (NOAA) began recording the levels of carbon dioxide in the atmosphere in 1950. Recently it has reported record highs for atmospheric CO2 content and an acceleration of the rate of increase. It is predicted that currents trends will warm the globe by around 4°C by the year 2100. To prevent this from happening, we need to cut emissions by seventy or eighty percent to simply stabilise atmospheric CO2 concentrations. The quicker we can do this, the better. From 1890 to 1990, the planet warmed by 0.5°C. 1987 saw the warmest year on record and the 1980's were the hottest decade so far. Even the coldest years of the 1980's were warmer than the warmest years of the 1880's. 1995 beat the record held by 1987 to become the hottest year to date. 2002 is the second hottest year on record and 2003 is the third hottest. However in Europe in 2003 the summer was the hottest for 500 years and there were an estimated 30,000 deaths as a result. But worryingly greenhouse gas concentrations still keep rising along with temperatures in a period when natural influences on climate such as solar cycles and volcanic eruptions should have cooled the Earth down. In its entire history, the Earth has probably never seen warming rates as rapid as those in the past 30 years.

So the evidence is strongly mounting up for global warming, but what will the impact of this warming be on our seas? In twenty years time if we returned to some of the most popular dive sites of today, what would have changed?


The Effect of Global Warming on Coral Reefs

Hard coral

Coral reefs are temperamental things. They only thrive in very specific conditions because of the symbiotic relationship they have with 'dinoflagellates', an algae that needs very specific conditions to live in. The dinoflagellates provide corals with food and oxygen in return for a protected living space and access to nutrients. They need sunlight to create energy through photosynthesis, which means corals only grow in light, clear and sediment-free waters. The temperatures they require are also specific: optimum growth occurs at 23 to 29°C, but they will tolerate temperatures between 18 and 40°C. Consequently, less than 0.2 percent of the global oceans are covered in tropical reefs. From this you can begin to understand why slight changes in the ocean can have profound impacts on reef distribution.

An analysis of the planets coral reefs has revealed that two-thirds of them are now severely damaged, a fifth so overwhelmingly that they are unlikely to recover. Some have been affected by global warming, and others have fallen to the mercy of over fishing. The Intergovernmental Panel on Climate Change predicts that global warming will increase sea temperatures by between 1.5 and 4.5°C this century, causing problems for reefs.

During the last Ice Age temperatures were only 4 to 5°C colder than they are today. Models predict that at the lower end of this limit - expected only if current greenhouse gas emission rates are reduced significantly - temperatures will stabilise at the end of this century and reefs will recover over the following century. At the upper end of the limit it will take at least five hundred years for reefs to regenerate. Aside from changes in temperature, there is the problem of the quantity carbon dioxide found within the sea itself. The worlds seas are one of the biggest 'sinks' (or absorbers) of carbon dioxide. As the amount of carbon dioxide in the atmosphere increases, then over time the ocean begins to absorb more carbon dioxide as well. The problem with this is that it makes the water more acidic - not good news for anything made from calcium carbonate, which includes corals and plankton, as they are easily dissolved by acid. Dissolved carbon dioxide could increase the acidity of sea water by as much as 0.5 pH units by the end of this century, from 8.2 to around 7.8 - more acidic than it has been for the past 20 million years. Such a change would upset the oceans' chemical balance and kill off marine life. It will take many thousands of years for natural processes to remove the carbon and as long as we keep putting carbon dioxide into the atmosphere it will keep finding its way into the ocean. Since the beginning of the Industrial Revolution, humans have pumped an estimated total of 450 billion tonnes of carbon dioxide into the atmosphere, around half of which has ended up in the oceans.

Its not only coral reefs though; global warming could severely reduce numbers of microscopic plankton at the base of the food chain, affecting all sea life globally. Warmer seas will limit the rise of nutrients - and with them plankton - from the deep oceans as mixing across stronger thermoclines is inhibited. With phytoplankton deeper in the seas, less CO2 might be absorbed from the atmosphere, exacerbating the problem of global warming.

A third consequence of global warming is sea level rise due to ice sheets melting, which threatens to drown low-lying islands like coral atolls unless coral growth can keep up with the rate of rise. If a large mass of ice were to melt reasonably rapidly, the resulting sea level change could mean coral growth would not be enough to give those dinoflagellates the amount of light they need. Global average sea level has risen by 2.8mm a year since 1993, but water levels within 100 kilometres of the coast have risen by an average of 3.7mm per year. If the Greenland Ice Sheet melts, which it is likely to do in the next 50 years, there would be a rise in global sea level of six metres - enough to flood land that is made home by millions of people as well as drown reefs. In Tuvalu in the South Pacific, they are already seeing the flooding of low-lying areas as well as experience more and more adverse weather conditions. The financial districts of London, New York and Hong Kong, to name but three, lie barely above sea level.

The IPCC predicts that if we go on as we are, by 2100 global sea levels will probably have risen by between 18cm and 59cm. However, recent research has suggested the polar ice caps may melt far faster under the pressure of global warming than previously thought. By looking at how the Earth has responded to temperature rises in the past, some scientists believe you could potentially get metres of sea level rise within then next hundred years rather than the next thousand. Without efforts to curb the rise of greenhouse gases, the world's ice sheets could retreat farther by the year 2100 than they have in the past 130,000 years, leading to a huge rise in sea level.

"Changes are happening at a rate that nobody appreciated," says Robert Bindschadler, an Antarctic researcher at NASA's Goddard Space Flight Center. Half of the sea-level rise predicted by the IPCC to occur this century has already taken place in the past decade.

One positive outcome for coral reefs could be that warmer water temperatures would increase the rate of coral growth; in fact some studies predict that corals will be growing 35 percent faster than they do today by the year 2100. Counter to this however is the argument that coral bleaching will occur, which is when corals expel their algal inhabitors and ultimately kill themselves, undoing the beneficial effects of the warmer water.


The Effect of Global Warming on Ocean Currents

Across the world, movement of water on a mass scale occurs due to differences in water salinity and temperature, and because of wind patterns. One example of a global current is the Gulf Stream, which is driven by differences in water temperature and salinity in the North Atlantic and at the equator. Surface water in the North Atlantic gets cooled by winds and becomes more salty, so it sinks to the ocean floor. At the equator, water is warmed up by the sun which causes an affect similar to a conveyor belt as water moves between the two. The Gulf Stream provides Northwestern Europe and the UK with warm waters and a rich source of nutrients. It also affects air temperatures which would be an average of 9°C cooler if the current did not exist.

At the end of the last Ice Age, an ice sheet covering North America melted which greatly reduced or maybe even shut down the Gulf Stream. It had the affect of causing temperatures to fall in Northwest Europe by 5°C in just a few decades. If the Greenland Ice Sheet was to melt it would add more fresh water to the North Atlantic, which would slow or stop the current. Current models predict that in the next 100 years, the Gulf Stream will weaken by 25%. As it weakens it will become more unstable and may therefore stop altogether. Aside from the huge affects this would have on land, temperature differences and a change in the amount of nutrients in the water would inevitably lead to marine creatures being unable to survive in the resulting conditions. Biodiversity will reduce and species will have to migrate (if they are able to fast enough) or adapt otherwise they will die out.


Signs of Climate Change around Europe and the UK

Europe is warming more quickly than the rest of the world and temperatures are expected to climb by a further 2°C to 6°C this century alone. One line of evidence for this is that Mediterranean species are becoming increasingly common around the UK. The sea around the UK is also changing to a greener colour from the blue it used to be because different types of plankton are now living in the water. Animals that used to feed on the plankton that has had to drift northwards to colder climates are dying out because they have less food to eat. This affects the entire food chain as in turn the birds and mammals that feed on the fish that are struggling to find enough food so are also reducing in numbers.

Sea levels are predicted to rise over the next few centuries, at a rate of up to four times faster than during the last century. This will affect low-lying regions and will have an unprecedented affect on countries such as the Netherlands, where half the population lives below sea-level. Precipitation patterns will change too by 2100, according to IPCC predictions with mid- to high-latitude regions seeing up to 20% more rain and snow, while the tropical regions will see less.


What can we do to help?

The responsibility to combat global warming lies with the individual as much as it does with governments and politicians. Try walking to work occasionally rather than driving, and turn off lights, televisions and computers whenever you are not using them. We need to be more efficient with how we use fuel to heat our houses and run our cars. If at all possible use energy from non-carbon based fuels such as wind energy and solar power.

We also need to put pressure onto political parties by voting for those with good environmental policies. The Kyoto Protocol on climate change, meant to be finalised in 1997, has finally come into force imposing cuts on greenhouse gas emissions from industrialised countries from 2008 to 2012. The cuts average 5.2% for the nations included in the Protocol - barely scratching the surface of the problem, but at least it's a step towards the right direction. The USA (the world's biggest emitter of greenhouse gases per country) and Australia (the world's biggest emitter per capita) are amongst the few developed countries that have not joined the Kyoto Treaty as they perceive that following its guidelines would damage their economies. The US believes that negotiations are "premature", and have therefore delayed talks until May 2005 where it will discuss possible post-2012 action. In February, former US vice president Al Gore criticised the Bush Administration of "moral cowardice" in declining to ratify the Kyoto Protocol, but he remarked that regional US efforts at tackling climate change have "filled the leadership vacuum".

If everyone in developing countries used the same amount of energy as the average consumer in high income countries does, the developing world's energy use would increase more than eightfold between 2000 and 2050. This massive increase in demand is already starting - for example with China's car sales rising by 82% in 2003 from 2002 and its demand for oil expecting to double in 20 years. However in the last decade, US oil use has increased by almost 2.7 million barrels a day - more oil than India and Pakistan use daily altogether.

Ultimately, in a world where money comes before the planet we call our home, economics will be the decider as to how and when we reduce global warming. Strategies that are good for business and the GDP will win politicians votes, so reduction of the greenhouse effect needs to be modelled accordingly.


Pollution of the Oceans: Sun, Sea, Sand and Squander

Whilst thinking about the destruction of habitats, it is also worth considering the impact that the human population is having on the natural world as we begin to spend more time in places which would have previously never have sustained large numbers of people. The construction of hotel complexes in places such as the Red Sea are undoubtedly having an effect on the coral reefs close to shore due to the pollution they create and the disruption of natural ecosystems. Twenty years ago there was only one large hotel near Hurghada; now the resorts stretch with barely a break from El Gouna through Hurghada and down to Safaga, and then you come across more in El Quseir and Marsa Alam. The house reefs have inevitably suffered as a consequence.

The list of items that cause pollution is a long one. Discarded rubbish and decaying waste represents a risk to marine creatures as well as being an eyesore. Coastal waters can suffer from agricultural run off and sewage discharge which can cause algal blooms, many of which are toxic. The toxins in the water then find their way into shellfish and fish, which when eaten by humans can cause food poisoning. Small islands are particularly vulnerable to pollution because they cannot sustain the numbers of people that live on them or visit them. The inevitable waste products that the human population brings with it simply cannot be disposed of without causing damage, especially if it is not managed well. The oil and gas industry also cause damage to the ocean environment, either through exploration or through spillages. More than 30,000 tonnes of oil is discharged into the North Sea alone every year from the thousands of wells the have been drilled there. Around 400,000 tonnes of crude oil is accidentally spilled every year by supertankers worldwide.


Over fishing

What is over fishing?
Over fishing is happening in seas across the world, occurring when marine life is removed from the water for human consumption in unsustainable levels. It is particularly bad in areas fished by industrial fleets, where insufficient international regulations and short-sighted management leads to the rapid decline of fish stocks. Fish are becoming smaller as older, larger fish are caught to be eaten. Older fish are more fertile so this means there is less chance of reproduction, leading to further decline of stocks and reducing the chance of recovery. The damage from over fishing can also be aggravated by pollution from coastal areas and ships.

Why is over fishing occurring?
The reason that over fishing continues in most countries is due to the economy relying on the income from the industry, especially on small islands such as those in the Pacific. The Asian Development Bank now estimates that fisheries contribute around seven percent of the Pacific Islands' GDP. In Vanuatu, over fishing has resulted in a sharp decline in catches from 90,000 tonnes in 1999 to less than 30,000 in 2001. However, it must be realised that if fish stocks continue to be exploited there will be less possibility of earning an income from fishing.

How is it affecting the oceans?
The Grand Banks off Newfoundland in Canada were once home to abundant numbers of cod, but persistent over fishing exhausted numbers within decades. The same is now happening in the North Sea off of the UK, where some of the most intensive fishing on the planet occurs. Ninety percent of the North Sea's floor is trawled at least once a year and in some places this reaches six times year. Inevitably this is taking its toll on fish stocks, leaving some areas in a state where they may never recover.

Practically nowhere in the UK remains untouched by the fishing industry: Britain's shallow coastal strips have already been nearly emptied of once abundant fish stocks, and it appears even deeper environments remain unscathed. As more popular species of fish decline in numbers, others species are fished to replace them, such as orange roughy. The damage this is causing is seen at Darwin Mounds in Northwest Scotland, home to 8,000 year old coral that has been damaged by deep grooves, gouged by fishing equipment. A previously unheard of ecosystem in the deeper parts of the North Sea has been discovered to contain coral blooms around eighteen feet high. Acoustic surveys of these reefs have also revealed gashes across the corals from deep-sea fishing equipment. In a recent survey to ascertain the numbers of common skate not a single one was seen. The exploitation of the sand eel fishery in the 1970's and 80's led to its collapse in 1990 when harvesting the eels was stopped because supplies were dwindling dangerously low. This had knock on effects as seabird populations in Shetland, such as kittiwakes that rely on sand eels for food, also began to dwindle.

Trawlers cause immense damage to the seabed, as they drag huge chains that weigh a colossal ten tonnes behind them. These fishing practices have been going on for years and the damage they cause has only been noticed relatively recently. Some conservationists fear the damage may be now be irreversible, as successive governments have failed to take any action to prevent it. Trawling the seabed for the Norway lobster (more commonly known as scampi) is destroying the homes of rare creatures such as the firework anemone. Other species threatened include oysters, leatherback turtles, pink sea fans and seahorses that live in seagrass beds that are being destroyed. Finally, the problem of 'by-catching', where fish that are accidentally caught in the huge nets used are then thrown away. This is threatening species such as the bottlenose dolphin and it's believed that some species could be wiped out within a decade. Figures state that up to 10,000 dolphins and porpoises are killed in the North Atlantic each year as by-catch.

The Royal Commission on Environmental Pollution believe that thirty percent of the waters around Britain should be designated as marine parks to maintain fish stocks and prevent the extinction of some species. Currently there only three: Lundy Island in the Bristol Channel, Skomer Island in Pembrokeshire, and Strangford Loch in Northern Ireland. Without nurturing fish stocks, fishing will eventually become too expensive to make economic sense so it is essential that action is taken quickly. This will not only to protect the species under threat but also sustain the fishing industry of the future. Attempts to reduce coastal pollution and restore damaged habitats will also help the recovery of depleted stocks.

Which species are being affected?
The fish that are under threat most from over fishing are haddock, cod, brill, plaice, grey mullet, wolf fish, swordfish, tuna and turbot amongst others. If you do enjoy eating fish, the following advice should help you to decide what not to eat. Try to avoid buying the species mentioned above in an attempt to force supermarkets to buy from sustainable sources. The best choice of fish to eat are shellfish and Pacific salmon. In the UK, Dover sole (if caught in the Eastern Channel), herring and mackerel (if caught in Cornwall) are the next best choice. Megrim is fine if caught in Western Ireland and the Western Channel. Deepwater species, such as monkfish, should not be eaten because little is known about how these stocks are replenished. With cod, some species come from an acceptable source - those caught by line in the Pacific are ok to eat whilst most Atlantic cod definitely isn't. Any fish that is caught using the destructive beam trawl method, including lemon sole, should not be touched.

Cod is a fish that has made the headlines a lot of late. It has been suggested that breeding patterns have collapsed because adults should live to the age of forty, but surveys have found that just 0.5 percent of the cod population is aged above five and nine out of ten are less than two years old. This is due to over fishing, partly because of the popularity of the fish in dishes such as fish and chips. Despite these findings, in December 2004 the EU decided not to ban fishing in crucial areas. A planned cut in the number of days that fishermen were allowed to fish for cod was also abandoned. Apparently Britain favours measures to preserve cod stocks, but believes the closure would not necessarily have been effective and would have unduly penalised its fishermen. The WWF recommends that to sustain a population of North Sea cod there should be no fewer than 150,000 tonnes of the fish and the current total stands at 46,000 tonnes, meaning cod could disappear within 15 years. Avoiding action is not going to help stocks recover. One ray of hope has appeared however: Britain's haddock numbers are on the increase and studies suggest that they have learned how to fit through fishing nets, with juveniles learning from adults.

Can fish farming help?
Farming fish or 'aquaculture' was designed to relieve pressure on marine resources and it now accounts for around twenty five percent of all fish consumed by humans. However aquaculture is fraught with problems. Some farms collect fry from local waters to farm for the next year. In the Philippines, too much fry is collected and ten billion fish are left discarded on the beaches each year. Carnivorous fish farming requires the use of fish oil and fish meal. For ten of the most commonly farmed fish, an average of 1.9 kilogrammes of wild fish is required for every kilogrammes of farmed fish that is raised, which is obviously unsustainable. Because of conditions in fish farms, diseases can quickly spread through the stock, which can also damage local wild fish populations. The way to manage fish farms effectively is to breed herbivorous fish only, employ the use of seaweeds to help clean waters and therefore reduce the amount of disease and to limit the number of fisheries found along each coast.

What can I do to help?

  • Dive in places with marine reserves: they are more picturesque and you'll be helping to get the message out that over fishing is not good for tourism.
  • Do not visit countries that have no environmental policies: their economies will suffer if enough tourists refuse to visit and they will have to do something about it.
  • Do not eat fish that are under threat from extinction (see above).
  • Demand proper labelling on fish products: ask stores where their fish come from. Current labelling requires stores to state vaguely where fish is from, like the Northeast Atlantic, but this does not tell concerned consumers whether the fish can be eaten with a clear conscience
  • Never buy products made from shark fins. The incredibly inhumane way of removing a shark's fin whilst it is still alive, then leaving it to die in the water is disgusting.

Sharks and shark fin soup

Great white - courtesy of Terry Nichols

When we think of sharks, many of us immediately start to conjure up images of a sleek, dark torpedo shaped assassin with a mouth full of razor sharp teeth and a thirst for human blood. In reality, however, a somewhat different picture is closer to the truth. It is true that evolution has honed these creatures with a simply awesome array of sensory equipment designed for the sole purpose of locating, tracking and immobilising prey. Their arsenal of weaponry and effortless ability to strike fear into the hearts and minds of man is the stuff of legend: they are indeed one of Mother Nature's finest creations.

Sharks belong to the super order Selachimorpha in the subclass Elasmobranchii in the class Chondrichthyes (cartilaginous jawed fish with paired fins and nostrils, scales and a two chambered heart). The Elasmobranchii also include rays and skates and their kind has roamed the oceans for some 400 million years. Many species of shark have come and gone over the millennia including the 375 million year old Stethacanthus and Caldoselache the deadly Cretoxyrhina Mantelli and the king of them all, possible king of all predators, the 50 foot, 20 ton Carcharodon Megalodon. A member of the mako family and possibly closely related to the modern day great white, this beast was the size of a grey hound bus with 6 - 8 inch serrated daggers lining a gape over 6 foot across. Our ancient seas were truly a dangerous place to be. Luckily Carcharodon Carcharias (Great White) is the largest predatory shark you'll find in our oceans today. Not that being alone with one of them would be any safer.

Armed with an olfactory system capable of detecting one part blood per million parts seawater and ophthalmic sensors highly tuned for nocturnal hunting thanks to the tapetum lucidum located behind the retina, this tissue reflects light back to the retina, thereby increasing visibility in low light conditions. A line of receptors known as nueromasts located down both flanks make up the lateral line. Similar to the hairs found inside the middle ear of many mammals these sensors, surrounded by a gel like substance called cupula, are able to detect vibrations in the 25 - 50 Hz range. Then we come to the Ampullae of Lorenzini: small skin pores concentrated in the snout and capable of detecting electric fields as weak as 5nV/cm (5/1,000,000,000 of a volt) not to mention temperature, pressure and most probably salinity.

Shark finning - courtesy of Terry Nichols

You would imagine therefore that sharks have little to fear in their natural habitat. True, many larger species hunt their smaller cousins and Orca will take a few but realistically sharks are at the very top of their respective food chains. Or are they? There is a species that resides above them in the food chain. A species more dangerous and ruthless than any shark, past or present that places nature's most perfect predatory design firmly on the endangered species list. That species is man.

According to official reports for the year 1980, about 3,000 tons of shark fins were traded worldwide and in 2004 it was 22,000 tons, a quantity which in all probability is much higher. Statistics from the Far East - including Singapore, Taiwan, and Hong Kong, the epicentre of the finning trade - all point to a massive increase in the trade of shark fins. Hong Kong and mainland China dominate the international shark fin market with a 50% share of all worldwide traded shark fins. 80% of the fins landed in Hong Kong are shipped to the Chinese mainland. In 2003 this amounted to some 11,000 tons and the market is growing each year by around 5% 3,500 tons are delivered directly to the Chinese mainland and fins from species that are supposed to be protected by the CITES Convention (the Convention on International Trade in Endangered Species) - including the whale shark, basking shark and white shark - flow uncontrolled into the market.

The reason: Shark Fin Soup.

Originally a regional delicacy in the Canton region of southern China up until the late 1980s it is traditionally regarded in Chinese medicine as a tonic, modern nutritionists finding it rich in protein, the gelatine contained is also said to help the growth of cartilage. The dish is cooked over very long period of time until the shark fin separates into needles of cartilage that look a lot like clear noodles. Incredibly, the fin itself has no taste, but is served with a stock of chicken, ham and shiitake to give it flavour.

Finning is the cruel process of hacking of the shark's fins, often while the animal is still very much alive, and then discarding the torso back into the sea. The fins only make up around 12-15% of the sharks total body weight, but unfortunately for the shark they fetch far more on the international market than the shark meat would yield. Shark fin can make on average USD £100 per kilo in Asia and it is because of this that many fishermen target sharks in order to make a living. Brazil, Canada, the US, Spain, Costa Rica, Malta, South Africa, the Philippines and the United Kingdom have all introduced restrictions on finning but it's not enough.

The trade continues, fuelled by ever increasing prices for fins - up to USD 4000 per kilo in some cases. And the sharks continue to be slaughtered in their tens of thousands. It's a sad fact for the sharks that being endowed as they are with such sophisticated sensory weaponry, form has inevitably followed function in nature's grand design bestowing these magnificent creatures with a cold and callous appearance. Although elegant, graceful and beautiful, cute and cuddly they are not. Had they the appearance of a baby fur seal, for example, I have little doubt the general public would have taken far greater notice of their plight. This is however not the case and restaurants throughout the country continue to offer this dish on their menus in a country that has long prided itself as being a nation of animal lovers.

Well Aquateach think it's high time we had our say on the matter by eliminating this frankly ludicrous dish from all restaurants up and down the UK and I am pretty sure that the vast majority of divers would share that sentiment. So what can we do? Dig out the red rubber wellies and blue Lycra suit? Any excuse I know, but there is another way. Simply keep your eyes and ears open for shark fin soup on a menu near you and let us know. Aquateach are running a campaign to put pressure on any outlet offering shark fin soup as part of their menu with the help of the media, persuasive conversation and the local mafia. Actually, that last part is a fib (the mafia are too expensive) but we are aiming to make shark fin soup as socially unpopular as seal clubbing and Jade Goodie and with your help we might just make it happen.

All divers have an affinity with sharks, whether it's a morbid fear or unhealthy fascination we all share a healthy respect and one thing I think we can all agree on is that the oceans would be a far less beautiful place without them.

By Terry Nichols, Aquateach


Blue shark - courtesy of ARKive

ARKive is calling on divers and underwater photographers for their help in gathering images of all the world's threatened marine animals and plants. ARKive promotes conservation and builds environmental awareness through wildlife photographs, films and sound clips – which are being pledged by many of the world's top photographers and filmmakers. The aim is to produce a global, centralized record of all 16,928 species on the IUCN Red List of Threatened Species. This will provide an invaluable conservation tool - a quick, easy and free online source of information for anyone keen to learn more or to help with conservation efforts.

Films and photographs are an emotive, powerful and effective means of building environmental awareness. They bring every species to life and demonstrate quickly and simply what makes them so special. Thinking about the non-divers - would they know what the Indonesian speckled carpet shark looks like, does it really have speckles? Does a spotted hand-fish really have hands? And what on earth is a Banggai cardinalfish or a seadragon?

Many divers, amateur and professional alike, take fabulous photographs of a broad range of threatened species, so this is an opportunity to work with ARKive and help the wide variety of amazing animals and plants that give pleasure to so many divers. Photographs and video give these threatened species a face, they give those who won't ever be lucky enough to see them in the wild the chance to understand their characteristics, their biology and the threats they are currently facing.

Threatened marine species make up just ten percent of the current material held in ARKive, reflecting just how hard these films and photographs are to collect, so the divers underwater images are urgently needed to help fill the watery gaps in the rapidly growing library.

TV presenter and passionate diver, Kate Humble, is a keen supporter of ARKive. "I love that first plunge, the first glimpse through the mask of the underwater world," says Kate. "And I know I am privileged to have experienced the ocean’s depths, many others are not so fortunate. So I encourage divers to donate their images to give ARKive the best means possible in their quest to raise awareness for the world’s underwater creatures." Her celebrity scrapbook on the ARKive website focuses on diving and includes some of the species she has been lucky enough to see whilst underwater for pleasure and work (such as when filming Springwatch).

Porbeagle shark - courtesy of ARKive

Professional shark photographer and regular ARKive contributor Andy Murch says, "Many of my shark images have been used in conservation campaigns to help push through legislation aiming to protect animals at risk. It's hard to raise support for an animal that has no face in the media and good images can make a huge difference. I feel ARKive is a shining example of what can be done to bring attention to the plight of the world’s endangered species. A project of this size is too large for individual photographers to take on but it is an obvious cause for us to contribute to."

The ARKive team are searching for a huge variety of marine materials and are keen to see the photograph captured from the cage when the diver comes face to jaws with a huge great white off South Africa or South Australia. They too will be mesmerised by the classic silhouette of swirling hammerheads filmed whilst gazing up into the clear blue waters of the Pacific. From the mighty pelagics that every diver longs to witness and photograph, right down to the camouflaged and almost impossible to see pygmy seahorses of the Pacific Ocean, ARKive is interested in them all – and the more unusual and obscure the species, the better.

A list of the 'most wanted' images is published on the ARKive website www.arkive.org and to check out if your species appears on the Red List see www.redlist.org. Anyone wishing to donate images can e-mail ARKive's media research team – arkive@wildscreen.org.uk, or upload to www.flickr.com/groups/arkive using the tag 'marine'.

So far around 38,000 films and images have been given a safe-haven in the ARKive digital vault. More than 3,000 media donors are actively contributing to the project, from major broadcasters, film and photo libraries to conservation organizations and academic institutes, as well as many individual filmmakers and photographers. All media is donated freely on the understanding that it will be used as a resource for scientists, conservationists, educators and the general public, and not for commercial purposes.

Debra Taylor, ARKive