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TL: GREENPEACE REPORT ON THE WORLD’S OCEANS - SUMMARY SO: GREENPEACE INTERNATIONAL, (GP) DT: MAY, 1998 Greenpeace Report on the World’s Oceans Summary The world’s oceans and seas cover 71% of the surface of the earth. This huge biological system comprises very diverse habitats and is, in some respects, richer in biodiversity than life on land more major taxonomic groupings (phyla) of animals can be found in the oceans than on land. Oceans are very important for human existence, not only because they supply us with fish and other coastal resources, but also because they function as a regulator of atmospheric composition, nutrient cycling and biological control of natural systems. Marine ecosystems are under continuously increasing pressure. The population of the world is rapidly growing and expected to reach some 7 billion by the year 2010, which means it will have doubled in little under 50 years. The majority of the population lives near the coast and the impacts of human activities are particularly evident in coastal regions. Measures are needed to protect the coastal and marine environment. Such measures should take into account that there are considerable uncertainties. Many of the processes normally taking place in the ocean are still not understood and it is, therefore, very difficult to predict the responses of ecosystems to human interference. The most widely accepted way to take such scientific uncertainties into account is through the adoption of the precautionary approach. Such an approach to environmental protection aims to take measures to prevent environmental damage by human activities, rather than attempting to react to problems after they have been detected. It recognises scientific and technical limitations and promotes regulatory action even where there is not conclusive evidence that the human activities cause environmental damage. A great number of international fora have adopted a precautionary approach to environmental protection, but it has not been effectively applied. Implementation of the precautionary approach needs to be a priority and actively supported, promoted and implemented by governments, intergovernmental organizations and the private sector. Inputs of polluting substances Of all polluting substances in marine environment, 77% come from human land based activities, while shipping and sea dumping are thought to contribute the remainder. Both naturally occurring and artificial substances like phosphates, nitrates, metals, radionuclides, and organic chemicals are being discharged. Some of these are systematically accumulating in the ecosphere. There is convincing evidence that widespread disturbance of biological systems is taking place as a result. Organic chemicals Organic pollutants like chlorinated pesticides (e.g. DDT, lindane), polychlorinated biphenyls (PCBs,) the chlorinated dioxins and the polycyclic aromatic hydrocarbons (PAHs) are toxic, persistent in the environment and can accumulate in the tissues of living organisms, causing a wide range of problems. Chemicals containing chlorine are produced deliberately as commercial products, but are also produced as unwanted by-products in chemical processes which use chlorine. Chlorinated chemicals have been a major focus of research and their impact upon the marine environment may increase in the future. PAHs are produced in industrial combustion and petrochemical manufacturing processes using fossil fuels as well as from natural sources such as forest fires. Because of the persistence of these chemicals, they will continue to damage the environment even after they are banned or their production is severely restricted. For this reason it is all the more urgent that restrictions and bans be implemented as soon as possible. Long-term research programmes have shown that persistent organic pollutants are globally transported towards the cold polar regions resulting in high levels of contamination in areas remote from sources of industrial pollution. The problem of global transport of persistent chemicals to remote regions is likely to increase. Many developing countries are beginning to use industrial processes which make use of toxic chemicals in part as the result of the export of outdated technology by industrial countries. In addition, pesticides that are highly restricted in industrialised countries are being increasingly used in agriculture and public health programmes in developing countries to control pests and diseases. This explains, for example, the presence of high residue levels of DDT in the atmosphere and waters of tropical Asia. Chlordane and PCB emissions also appear to be increasing in tropical countries. Transport from these areas to remote polar areas appears to be inevitable. Even when regulatory measures are taken, high levels of some of these pollutants will persist for many decades in those remote areas. Pollution by organochlorines in remote areas can, therefore, only be brought under control by a complete ban on their production and use throughout the world. These chemicals, moreover, are only a small component of all the chemicals discharged to the marine environment, many of which cannot be easily identified. Radioactive pollution Radioactive isotopes are another class of polluting substances for which the current scale of environmental impact is uncertain and a matter of serious concern. Low level concentrations of artificial radionuclides are measurable in the oceans world-wide as a result of discharges from nuclear facilities and weapons testing. Radiation can damage organisms at a cellular level and cause cancer or genetic mutations. Although the largest source of artificial radionuclides in the oceans resulted from the fallout from weapons testing, other sources are the nuclear industry and the military, whose dumping, accidental losses and discharges provide highly localised inputs. In particular, plants where spent nuclear fuel elements are reprocessed have become major contributors of radioactive discharges. Two major commercial reprocessing operations are located in Europe (La Hague, France and Sellafield, UK) but others are known to exist in Japan, India and Russia. The discharges of the European reprocessing plants have risen significantly in the past decade and have resulted in elevated radiocaesium levels over the whole of the North Atlantic. The increased nuclear reprocessing discharges have serious implications for marine and terrestrial food chains since marine and estuarine organisms are able to accumulate radionuclides. In 1996, concentrations of 17,000 Bq/kg technetium-99 were measured in lobster found off the coast of the reprocessing plant in Sellafield. This was twice as much as the concentration measured in 1995 and 44 times as much as in 1993. Many of these discharged artificial radionuclides have extremely long half lives and are unknown in nature. Continuing discharges cause a build-up of these elements in the ecosphere. In keeping with the precautionary principle, the discharge and emission of nuclear reprocessing wastes must be stopped. In addition to the artificial sources of radionuclides, naturally occurring nuclides are mobilised in large quantities by oil production and phosphate rock processing for fertiliser and detergent manufacture. This rock processing can lead to marine animals, particularly fish, accumulating high levels of the isotope polonium-210, and these can be an important source of polonium-210 to humans. Knowledge of the physical behaviour of nuclides in the environment is very incomplete. Even less is known about the effects upon wildlife of continual long-term, chronic exposure. Environmental protection from radiation is based on the assumption that if humans are adequately protected, then other living organisms are likely to be so too. But this crucial assumption has little scientific basis. In any case, it is clear that levels of radioactivity in some organisms in the natural environment may exceed human dose rates by a large margin. For instance, a maximum dose of 1mSv per year is recommended for humans but grey seals near Sellafield were estimated to be exposed to a dose of 36 mSv per year from the isotope caesium-137 alone. Given the lack of knowledge and uncertainties about the environmental impact of the long lived, persistent radionuclides and organic chemicals, a precautionary approach to the regulation of these hazardous substances is to eliminate discharges and emissions. Marine fisheries Marine fishing is an important human activity. It generates around 1% of the visible global economy, and together with related industries it supports the livelihoods of around 200 million people globally. Fish stocks around the world are being too intensively exploited. According to the most recent FAO figures, most major fisheries are fully to over exploited. The decline of many fish stocks is due to poor management and regulation. The problem is that too many boats are chasing too few fish. Estimates suggest that the global fishing fleet has 30-50% more capacity than needed to sustainably harvest the worlds stocks and the key to this overcapacity problem is found in the heavy subsidies provided by governments. As a result of overcapacity in world fishing fleets, the costs of fishing have been estimated to exceed the gains by some $US 16 billion annually. For every single dollar earned in 1989, for example, the costs associated with catching the fish were $US1.77. While the continuing subsidies to the industry may help to soothe economic impacts of fisheries decline, it does so by encouraging continued over-exploitation of resources. Fisheries management is generally based on biological advice on stock estimates and predictions. This advice is used to set a quota that should control fishing mortality. The inadequacies of current management systems are exposed by fisheries that have collapsed together with documented examples of continued overexploitation of fish stocks. Collapse and overexploitation occur even where a good body of data exists to inform managers. The cod and herring stocks in Canada and the North Sea are such examples. This leaves little hope for the stocks that are overexploited in the absence of good data. The Southern Bluefin Tuna for example is a highly migratory stock whose biology is incompletely understood. It is fished by a number of nations, and fishing is poorly regulated on an international level. As a result the stock is in a critical state. If current catch rates continue and Japan increases its catch, in defiance of international agreements, then there is around a 60% probability that the number of spawning adults of the stock will be reduced to zero by the year 2020. This would result in commercial extinction of the species, if not actual extinction. Fisheries do not only affect the targeted fish stocks, but impact the whole ecosystem. The most compelling evidence of general global scale ecosystem disturbance has been provided by reanalysis of FAO fisheries data. This has revealed the trend of progressively fishing down food chains. After depletion of the original target stock, the fisheries sector responds by targeting species that feed lower in the food chain. Hence, there is a trend in global fisheries of shifting from predatory demersal fish to pelagic fish lower in the food chain. This strategy brings with it a real possibility of wholesale changes marine ecosystems by altering the way in which energy flows through them. Depending on the local situation, the end result could be a complete shift away from commercially exploitable fish populations. One hypothesis, for example, is that the Southern North Sea could become dominated by jellyfish as top predators rather than commercially exploitable species. Bycatch of non-target species and discarding of unwanted catch also contribute to altering species balance and ecosystem dynamics. Bycatch is a feature of many fisheries and is a problem of global dimensions. Discarded bycatch in the global fishing industry are estimated at some 27 million tonnes, of which 37.2% are associated with various shrimp fisheries. Bycatch not only affects commercial and non-commercial fish species, but also bottom dwelling animals, whales, sea turtles and birds. Longlining for example is accompanied by large bycatches of seabirds. Some albatross populations such as the wandering albatross on Macquarie Island have been driven almost to extinction. Fishing gear also causes physical disturbance. In heavily fished areas, the bottom may be trawled several times a year. Dredges and bottom trawls are highly damaging to marine habitats. They scrape or plough the seabed, disrupting sediment, destroying habitat and killing large numbers of bottom-dwelling organisms. Severe habitat destruction can also occurs in coral reef fisheries. The use of cyanide poison to stun fish can kill most reef organisms, leaving much of a reef dead and degraded. Dynamite fishing also causes physical destruction of the reef environment. Aquaculture Aquaculture is a booming business, due to the rapid growth in demand for high value marine products like salmon and shrimp. The recent expansion in production of these species is reflected in an explosive increase in the number of intensive culture operations in coastal areas. Improvements in yield per unit area have been achieved by using high value feedstock and by using antibiotics and pesticides to control diseases and parasites. While traditional extensive methods of shrimp production yield between 100 and 500 kg shrimp per hectare, intensive pond culture can increase this to 1000-10,000 kg per hectare. There are many environmental problems associated with intensive aquaculture of marine species in the coastal zone. A clear example is the large-scale destruction of mangroves in Asia and Latin America for the construction of intensive aquaculture facilities. In the Philippines, aquaculture has contributed significantly to the removal of 75% of the original mangrove habitat. In Ecuador, the rapid growth of shrimp production had claimed 12,000 ha of virgin mangrove by 1987. Intensive shrimp ponds developed from mangroves are usually abandoned as soon as yields begin to fall. This occurs as a result of declining water quality. Poor husbandry and inadequate waste management cause outbreaks of disease. Subsequently, new areas are cleared and developed. The mean lifetime of such ponds in Thailand is estimated at only 7 years. This method of shrimp production is ultimately unsustainable. This became clear when aquaculture production crashed in Taiwan in the late 1980’s due to high costs, pollution and disease. Such unsustainable ‘shifting aquaculture’ operations supply a large proportion of global shrimp production at the expense of destroying irreplaceable coastal ecosystem. Intensive aquaculture emits large quantities of nutrients and organic matter into the environment. For every tonne of cage-farmed salmon produced, an estimated 2.5 tonnes of organic waste may be generated. In intensive shrimp ponds ammoniacal nitrogen is accumulated, which can be highly toxic to many marine species. Although both cage and pond aquaculture undoubtedly lead to local increases in nutrient loading, there is hardly any information on direct impacts. The aquaculture industry uses a variety of antibiotics, pesticides and detergents. Information on the types and quantities of chemicals employed in many countries is very scarce. Many of the chemicals used to control disease are toxic to a range of species, persistent in the environment and able to accumulate in biological tissues. They may create problems with residues in the cultured fish and shrimp, affect the surrounding environment, and allow antibiotic-resistant bacteria to enter the environment. Some of these bacteria may be pathogenic to marine species or even humans. In addition, the escape of farmed fish from cages may alter the genetic composition of wild stocks if they interbreed, resulting in reduced fitness of wild species. Despite development of regulations and technological improvements, the environmental and health problems of aquaculture remain significant and seem set to increase, given the continued economic pressure for growth of the aquaculture industry. Impacts of shipping Seaborne trade increased by around 45% between 1986 and 1995, and currently shipping is responsible for the carriage of some 80% of the volume of goods traded globally. Ships can cause a variety of problems in marine ecosystems. Many of the goods transported are hazardous. Losses of hazardous packaged goods such as pesticides occur regularly although such incidents are not systematically recorded. Chemical tank washings, discharge of oily wastes and oil-contaminated ballast and wash waters are significant sources of marine pollution. Shipping is responsible for an estimated 568,000 tonnes of oil entering the marine environment annually. Marine engines are also among the most highly polluting combustion sources, due to the use of low grade residual oils as fuel. Ships are, therefore, significant contributors to atmospheric pollution. Another important pollutant associated with shipping is the chemical applied to the hull of the ship to prevent the growth of fouling organisms. The most commonly used antifouling preparations contain tributyl-tin (TBT), a very toxic chemical. This acts as an endocrine disrupting chemical in marine snail species. Even extremely low concentrations can cause population declines by affecting their reproduction. TBT has also been found in the blubber of several marine mammal species. Finally, ballast water of ships can contain species of plants and animals that are removed from their native ecosystem and introduced in another. The impacts of such alien species are not well documented in most areas but, where information is available, for example the invasion of American comb jellyfish in the Black Sea, the impact can be severe. Offshore activities The offshore oil industry discharges large quantities of oil-based drilling muds with drill cuttings. These muds are toxic and have been found to affect reproductive development in bivalves and immune response in fish. Effects on overall benthic community structure have been detected on a distance as far as 2-6 km from disused platforms in the North Sea. Production waters are also discharged into the sea. These contain not only oil but also chemicals that either originate when the oil or gas forms, or are added during the treatment of the hydrocarbons at the production platform. The use of chemicals is poorly controlled and documented, but it is clear that they can contribute to contamination of drill cuttings and produced waters. Some of the chemicals used, such as nonylphenol, can disrupt the hormone system and the reproduction of fish. In comparison to land-based industry in Europe, the offshore industry is relatively poorly regulated. There is a requirement for greater transparency and control of offshore operations. At minimum the offshore industry should be bound to apply the restrictions which exist for the dumping and discharge of wastes from other industries. This includes the need to ban the dumping at sea of the hundreds of offshore oil and gas installations that are due to be decommissioned in the next decades, given that not enough attention has been given to the “cumulative impact” of the dumping at sea of many large installations, nor to the environmental benefits arising from steel recycling (particularly through CO2 emission savings). Climate change Since pre-industrial times, concentrations of carbon dioxide, methane, nitrous oxide and industrially produced gases, including the CFCs, fluoroform and sulphur hexafluoride have risen steadily in the atmosphere. These gases all have in common that they act as "greenhouse" gases. These trap solar radiation reflected from the surface of the Earth. Carbon dioxide emitted from the burning immense quantities of fossil fuels is the largest contributor to the effect. Based on computer models and temperature measurements in the atmosphere, it is estimated that the increase of the global average surface air temperature between 1990 and 2100 will be between 1 and 3.5 ºC. Such an increase is extremely large and will be associated with major climatic changes around the world. Model predictions are highly uncertain, due to natural variability and poor understanding of global processes and feedback mechanisms. Nonetheless the Intergovernmental Panel on Climate Change in 1996 considered that "climate has changed over the past century" and that "the balance of evidence suggests a discernible human influence on global climate". Potential impacts of climate change upon the oceans have been less studied than the impacts upon terrestrial systems. This does not mean that such impacts are likely to be negligible. The oceans play a central role in shaping the earth’s climate and its natural variability. Oceans absorb carbon dioxide and other atmospheric gases, and their circulation redistributes heat and water. The most obvious potential impact of climatic change is on sea level. Over the past 100 years, global sea level has risen by between 10 and 25cm. For each centimeter of sea-level rise, beaches may erode a meter landward; for every 10-cm rise, saltwater wedges in estuaries and tidal rivers may advance a kilometer; and any sea-level rise will increase salinity in freshwater aquifers. Rising of sea levels will result in land-loss and coastal habitat loss in many countries. Bangladesh may lose 17.5% of its land area, and this could be as much as 80% for Majuro Atoll in the Marshall Islands. Increases in water temperature are likely to have severe impacts upon coral reefs by contributing to bleaching of corals. A consistent prediction of the mathematical models used to study climate change is that changes are likely to be greatest in the polar regions. These regions play a fundamental role in ocean circulation patterns. In turn, these determine climate patterns over the rest of the globe. Climate change in the polar regions may, therefore, not only directly change these biologically rich marine ecosystems, but also induce other changes worldwide. For example, according to models and observed trends, the Arctic is warming faster than the rest of the world. Precipitation in the region is likely to increase by 3-6% per degree of warming. A recent analysis suggests that the areal extent of sea ice in the Arctic has decreased by 2.9% ±0.4% per decade since 1978. Arctic glaciers are also retreating. The ice thickness of Alaskan glaciers has decreased by around 10m over the last forty years. Increased precipitation and melting of ice could make the upper layers of the Arctic less saline. This, in turn, could change the thermohaline circulation which drives the global ocean circulation and the regional current systems. These changes are also mirrored in the collapse of Antarctic ice-shelves in recent years. In addition to the warming of polar regions, important human impacts upon the natural stratospheric ozone have been detected. Every spring for over 20 years a hole has appeared in the ozone layer over Antarctica and has increased in size over the years. Substantial depletion of the ozone layer over the Arctic is now also being recorded. The production and use of various chlorinated and brominated chemicals are responsible for this ozone depletion. This depletion has resulted in increased levels of UV radiation at the earth’s surface. UV-B radiation is detrimental to various marine species in the upper layer of the ocean and reduces primary production, which is the basis of marine food webs. This may have a considerable impact on marine ecosystems on a global basis. CONCLUSION The Greenpeace Report on the World’s Oceans is a comprehensive, but by no means exhaustive, review of the many threats facing the world’s oceans and seas today. 1998 has been designated by the United Nations as the International Year of the Ocean. Greenpeace has been actively campaigning on a variety of oceans related issues for the past 27 years and has put forward a set of ten demands to governments and the UN system. Greenpeace is calling on governments to meet these demands to effectively address the problems outlined in the Greenpeace Report and to make the UN Year of the Ocean a meaningful event. The failure of governments to seize the opportunity and act decisively will result in continued degradation of the world’s oceans at the expense of present and future generations of humankind and the health and abundance of all life dependent on the seas.