The oceans and seas

Sustainable Development Goal 14

Conserve and sustainably use the oceans, seas and marine resources for sustainable development


Oceans occupy more than 70% of the Earth’s surface and 95% of the biosphere, provide critical life supporting services to the global population, and are essential to sustainable development and the health of the planet and well-being of its people. Marine and coastal environments contain highly diverse habitats that support an abundance of marine life. Life in the oceans and seas produces a third of the oxygen that we breathe, offers a valuable source of dietary protein, and moderates global climatic change. Examples of marine and coastal habitats include mangrove forests, coral reefs, sea grass beds, estuaries in coastal areas, hydrothermal vents, and seamounts and soft sediments on the ocean floor a few kilometres below the surface.

Oceans provide ecosystem services that are not only critical to the healthy functioning of the planet but also to sustainable economic growth and social welfare, as they are an important source of sustenance, medicine, livelihoods, recreation and cultural value for populations around the world. Over three billion people depend on marine and coastal resources for their livelihoods. Oceans contribute to poverty eradication by creating sustainable livelihoods and decent work in fisheries and marine aquaculture, shipping and shipbuilding, ports, tourism, oil, gas, mining and maritime transportation industries. Oceans are crucial for global food security and human health. Fish provide 4.3 billion people with about 15% of their intake of animal protein. The global oceans-based economy is estimated USD 3-6 trillion/year. Oceans are also critical to many important global processes, such as climate regulation and carbon cycling. Oceans are the primary regulator of the global climate and an important sink for greenhouse gases. Nearly all living things on earth depend on the oceans in one way or another.

Marine protected areas (MPAs) protect sedentary species and species during critical stages of their life as well as act as insurance against unsustainable fishery management. They have been shown to increase not only the average size of organisms, but also their density within their boundaries. They enhance fish populations outside of the reserve by spillover into adjacent areas. Studies have shown that MPAs can lead to improved fish catches and bigger fish, job creation, improved local governance, and benefits to public health and to women. Some 8.4% of areas within national jurisdiction (0-200 nautical miles) are protected through marine protected areas, and only 0.26% of marine waters beyond national jurisdiction are protected as deep-sea fisheries and the “global marine commons”.

Among the targets proposed for SDG 14 is to, by 2020, sustainably manage and protect marine and coastal ecosystems to avoid significant adverse impacts, including by strengthening their resilience, and take action for their restoration, to achieve healthy and productive oceans. Each of the Aichi Biodiversity Targets is relevant to this objective. With regards to other objectives of SDG 14, Aichi Biodiversity Targets 3, 6, 8, 10, 11, 14, 17 and 19 are particularly relevant.


Oceans are facing growing threats from overfishing, climate change, pollution, habitat destruction and invasions of exotic species, which are causing an unprecedented loss of biodiversity in the oceans and negatively impacting efforts to achieve sustainable development. Overfishing is widely acknowledged as the greatest single threat to marine wildlife and habitats. Nearly 70% of the world's fish stocks, according to the Food and Agriculture Organization of the United Nations, are now fully fished, overfished or depleted. Oceans are also under-protected, with just over 1% of the ocean surface designated as protected areas, compared to nearly 15% of protected area coverage on land.

Of the world’s coral reefs--some of the most diverse and valuable ecosystems on Earth-- about 20% of them have been effectively destroyed with no immediate prospects for recovery; about 16% of them were seriously damaged by coral bleaching in 1998, but of these about 40% have either recovered or are recovering; about 24% of the remaining reefs are under imminent risk of collapse through human pressures; and a further 26% are under a longer-term threat of collapse.

Other causes of concern relate to marine pollution, which originate from a number of marine and land-based sources (more than 80% of marine pollution), invasive alien species which may outcompete local marine species, ocean acidification and climate change impacts, or the unsustainable extraction of marine non-living resources (e.g. deep sea mining, offshore oil and gas drilling).


  • Oceans include highly diverse habitats — such as coral reefs, mangrove forests, seagrass beds, estuaries, open-ocean and deep-sea habitats — that are both ecologically and economically important.
  • Oceans cover 70% of our planet but their tremendous wealth of biodiversity and ecosystem services are not infinite. More than just a valuable source of food, oceans play a key role in regulating the global climate as they store over 15 times more carbon dioxide than the terrestrial biosphere and soils.
  • Over three billion people depend on marine and coastal biological resources for their livelihoods. With one in eight people in the world today undernourished, responsible and sustainable fisheries and marine aquaculture have an essential role to play.
  • The achievement of healthy productive and resilient oceans is indispensable to poverty eradication and sustainable development. To meet this objective, the international community will have to ensure conservation and sustainable use of the oceans and seas and of their resources, reduce the incidence and impacts of pollution, prevent introduction of invasive alien species, and address ocean acidification and the impacts of climate change.
  • The world’s fisheries employ more than 180 million people, with the global marine fish catch worth US$70 to 80 billion per year.
  • Overall, marine ecosystem services are valued at US $4.5-6.7 trillion annually.
  • The rich variety of life in deep-sea habitats, such as seamounts, hydrothermal vents and cold-water corals, plays a major role in global fishery production and provides a valuable source of marine genetic resources.
  • Concern is growing about the impacts of ocean acidification, as a direct consequence of increased carbon dioxide concentration in the atmosphere. Increasing acidity of sea water will reduce the availability of carbonate minerals in seawater, important building blocks for marine plants and animals, thereby potentially disrupting large components of the marine food web.