The Push to Safeguard 30% of the Ocean

Marine protected areas are essential to achieve full sustainability

Fish school
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The ocean covers more than two-thirds of the Earth’s surface and produces more than half of the oxygen on the planet. It provides sustenance and income for billions of people and plays a vital role in regulating climate around the globe.1 It is home to nearly a quarter of the world’s known species—and many more yet to be discovered.2 But the health of the ocean is increasingly threatened by coastal development, climate change, pollution, harmful fishing, seabed mining, and other extractive activities.

In 2016, members of the International Union for Conservation of Nature (IUCN) called for protecting at least 30 percent of the ocean by 2030 through a network of marine protected areas (MPAs) and other effective conservation measures. This recommendation also pertains to the high seas—areas beyond the jurisdiction of any country. According to the IUCN, an MPA is a clearly defined geographical space that is recognized, dedicated, and managed through legal or other effective means to achieve the long-term conservation of nature.3

Biological benefits of 30%

Protecting at least 30 percent of the ocean through MPAs is essential to meet a broad range of environmental and economic goals. Studies have demonstrated that marine reserves—the strongest form of MPA, in which all extraction is prohibited—can restore ocean health by protecting biodiversity, enhancing ecosystem resilience,4 supporting fisheries productivity, and safeguarding unique cultural traditions historically tied to the seas. Creating protected areas yields many benefits, including some that reach far beyond the MPA boundaries. For example:

  • MPAs can help connect important feeding, mating, and calving grounds for vulnerable species. They create healthier ecosystems that can generate essential revenue for island and coastal communities through sustainable fisheries and tourism.
  • They can help build ocean resilience to climate-related disturbances such as ocean acidification, sea level rise, increased storm intensity, shifts in species distribution, decreased productivity, and reduced oxygen availability.5
  • MPAs that are well-designed and properly enforced can produce remarkable ecological gains, including higher biodiversity and density of species, the ability to restore fisheries beyond the protected area, and greater ecosystem resiliency.6
Humpback whales migrate seasonally, and marine protected areas such as Mexico’s Revillagigedo Archipelago National Park can offer refuge during their travel.
Pelagic Life

Global targets for ocean protection

The Convention on Biological Diversity (CBD) is a legally binding international treaty that seeks to ensure conservation of the world’s biological diversity and promote the sustainable use and equitable sharing of the benefits of that biodiversity.

In 2020, the parties to the 15th meeting of the Conference of the Parties to the CBD are expected to adopt a new 10-year global biodiversity framework with goals and targets for ocean protection. Because MPAs play such a critical role in mitigating pressures on marine biodiversity and threats to food security, the Pew Bertarelli Ocean Legacy Project is working to ensure that parties to the conference follow recommendations that call for protecting at least 30 percent of the ocean to help conserve biodiversity effectively. Research shows that marine reserves are most successful when designated alongside well-managed fisheries zones, so a goal to achieve sustainable fisheries in the remaining areas will help foster overall ocean health.

Ensuring meaningful protections

Over the past decade, nations have increasingly used marine protections to safeguard major areas of waters, including the creation of large MPAs such as the Papahānaumokuākea Marine National Monument by the United States in the Northwestern Hawaiian Islands in the Pacific Ocean.

The IUCN—the global authority on the status of the natural world and the measures needed to safeguard it—provides guidelines to help countries determine when areas meet internationally accepted standards for marine protection. For example, the organization emphasizes that the main purpose of an MPA must be conservation; extractive activities must have low ecological impact and be aligned with the conservation objectives of the area. Activities such as industrial fishing, infrastructure developments, or mining are not compatible with the goals of protection. These guidelines will help countries more accurately report their MPAs to the World Database on Protected Areas, a step that will improve global accounting of how much of the ocean is truly protected.

The IUCN standards give governments, nongovernmental organizations, and other stakeholders the ability to better track progress toward global targets for ocean conservation and can be used to plan and create new MPAs that meet global standards and deliver real benefits toward ocean protection.7 A network of welldesigned and effectively managed MPAs that meet IUCN standards could greatly improve the health of the ocean, help achieve conservation targets, and avoid creation of protected areas that fail to provide expected ecological benefits.

Manta Ray
Large marine protected areas such as the Papahānaumokuākea Marine National Monument—home to more than 7,000 species, including this manta ray—boost the resilience of marine life against the impact of climate change.
Todd Aki


Extractive activities and human-made threats are taking a toll on marine ecosystems around the world, but MPAs are cost-effective, low-tech tools that research shows can help reverse this trend.8 In addition, they can provide benefits far beyond the boundaries of the protected area. These benefits include helping to alleviate some of the expected impacts of climate change and maintain traditional cultures closely linked to the sea. Increasing protected area coverage to at least 30 percent by 2030 would help mitigate many challenges to ocean health and allow future generations to reap the great benefits provided by these waters.


  1. National Oceanic and Atmospheric Administration, “Why Should We Care About the Ocean?” accessed July 18, 2018,
  2. Camilo Mora et al., “How Many Species Are There on Earth and in the Ocean?” PLOS Biology 9, no. 8 (2011): e1001127,
  3. International Union for Conservation of Nature and World Commission on Protected Areas, “Applying IUCN’s Global Conservation Standards to Marine Protected Areas (MPA)” (2018),
  4. Enric Sala and Sylvaine Giakoumi, “No-Take Marine Reserves Are the Most Effective Protected Areas in the Ocean,” ICES Journal of Marine Science 75, no. 3 (2017): 1166-68,
  5. Callum M. Roberts et al., “Marine Reserves Can Mitigate and Promote Adaptation to Climate Change,” Proceedings of the National Academy of Sciences 114, no. 24 (2017): 6167-75,
  6. Jane Lubchenco and Kirsten Grorud-Colvert, “Making Waves: The Science and Politics of Ocean Protection,” Science 350, no. 6259 (2015):
  7. International Union for Conservation of Nature and World Commission on Protected Areas, “Applying IUCN’s Global Conservation Standards.”
  8. Sarah E. Lester et al., “Biological Effects Within No-Take Marine Reserves: A Global Synthesis,” Marine Ecology Progress Series 384 (2009): 33-46,
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