An international team of scientists has called for the creation of marine protected areas in the open oceans to protect the world’s sea life from growing damage and loss caused by overexploitation, pollution and other human impacts.
The open oceans make up 99 per cent of the total region inhabited by life on Earth – yet are currently among our least-protected ecosystems, the researchers say in an opinion article in the world’s leading ecology journal.
They argue that pelagic ecosystems – the high seas – are in as urgent need of protection as the coastal areas where marine protected areas (MPAs) have already been declared, or areas that fall within national maritime boundaries.
“Pelagic ecosystems now face a multitude of threats including overfishing, pollution, climate change, eutrophication, mining and species introductions,” the researchers warn in the journal Trends in Ecology and Evolution (TREE). These threats can act together to cause far greater damage to marine food chains, fish stocks and ecosystems.
“Mobile pelagic species also suffer from the cumulative impact of sublethal stressors. Chronic exposure to chemical and acoustic pollution from shipping, military activities or oil and gas exploration and exploitation can lead to immunosuppression and reproductive failure in marine mammals ,” they add.
The high seas provide almost 80 per cent of humanity’s fish supplies, carry out half the photosynthesis (conversion of solar energy to sustain life) that takes place on the planet and, through their ability to absorb CO2, are a dominant influence over the speed and extent of climate change.
“It is clear from declines in many species that there is inadequate protection for pelagic biodiversity and ecosystems,” the researchers from Australia, South Africa and Poland say.
“Fewer protected areas exist in the open ocean than in any other major ecosystem on Earth,” explains Professor Bob Pressey of the ARC Centre of Excellence for Coral Reef Studies, a co-author of the article.
“Although there is growing support for the idea of marine protected areas in the open oceans, critics have argued they would be difficult and costly to enforce and manage in the ever-changing ocean environment.
“However my colleagues and I consider that recent advances in conservation science, oceanography and fisheries science can provide the necessary evidence, tools and information to operate these ‘ocean parks’ for the conservation of marine species that live in the high seas.
“But, to be frank, we won’t know how difficult it is until we try,” he adds.
The scientists argue ocean protected areas should be seen as simply another form of MPA, except that they will extend in three dimensions – across the surface and deep into the water itself.
They note that on the high seas, there is no single global body with the authority to establish protected areas or to regulate access to and use of an area for more than one purpose.
However they say progress can be made through Regional Fisheries Management Organizations, the International Maritime Organisation and by individual countries doing more to protect the outer parts of their 200 mile sovereign territories.
They point out that establishing the Pelagos Marine Sanctuary in the Mediterranean had the effect of encouraging countries such as Italy to tighten controls over the discharge of industrial
pollution into the sea.
By reducing the cumulative impact of human activities on the world’s oceans, MPAs can help to mitigate the severity of particular threats that cannot be directly controlled: “For example, if pelagic systems of the Black Sea had not suffered severe pollution and overfishing, they would have been less vulnerable to invasive species,” the say.
“Despite the challenges highlighted here, there are also enormous opportunities for MPAs in the pelagic ocean: weak private property rights, limited habitat transformation and potentially lower costs of protected area management,” the researchers say.
“We believe that pelagic MPAs have now come of age as an important tool in the planet’s last frontier of conservation management.”
Professor Bob Pressey, CoECRS, ph +61 7 4781 6194, mobile +61 0418 387 681
Dr Edward Game, The Nature Conservancy, +61 7 3214 6921
Jenny Lappin, CoECRS, +61 7 4781 4222
Jim O’Brien, James Cook University Media Office, +61 7 4781 4822 or +61 0418 892449