The Western Pacific Ocean

Underwater seamounts need to be studied as mining interest grows

Navigate to:

The Western Pacific Ocean
western pacific ocean
Zhang Jiansong/Xinhua/Alamy


Seamounts are large underwater mountains found throughout the world’s oceans. Home to deep-sea corals, mollusks, crustaceans, and large schools of fish, they are often classified as biodiversity hot spots. And yet these vital ecosystems remain poorly studied. By one estimate, less than 4 percent of the world’s seamounts have been directly sampled.1 In the Western Pacific Ocean, the mineral-rich crusts of these mountains are attracting the interest of potential deep-sea miners.

Cobalt, nickel, copper, platinum, and rare earth elements are found within the outermost crusts covering the flanks and summits of seamounts in the Western Pacific. Mining seamounts would involve removing the cobaltrich outer layer—eliminating or degrading habitats and causing significant ecosystem impacts in the process. Sediment plumes could smother life forms even beyond the mining zones.

Given their significance as habitat and biodiversity hot spots, seamounts may require protections to minimize damage from mining. Because so much remains unknown about seamounts and nearby habitats, a precautionary approach is needed when it comes to exploration and potential mineral extraction.

The International Seabed Authority (ISA) is responsible for managing the mineral resources of the high seas “for the benefit of mankind.” Under the U.N. Convention on the Law of the Sea, the ISA is tasked with both managing seabed mining and protecting the marine environment from harmful effects of that mining. The authority is drafting rules that will attempt to honor both imperatives. The Pew Charitable Trusts and other international conservation organizations are calling for an environmentally precautionary code, one feature of which would be the establishment of large ecologically important no-mining zones in areas such as the Western Pacific.

western pacific ocean


  1. Kristina O. Kvile et al., “A Global Assessment of Seamount Ecosystems Knowledge Using an Ecosystem Evaluation Framework,” Biological Conservation 173 (2014): 108–20,
  2. Sergei Petukhov et al., “Geodynamic Features of the Northwestern Part of the Magellan Seamounts, Pacific Ocean,” Journal of Geography and Geology 7, no. 1 (2015): 35–45,
  3. Secretariat of the Pacific Community, “Cobalt-Rich Ferromanganese Crusts: A Physical, Biological, Environmental, and Technical Review,” vol. 1C, eds. Elaine Baker and Yannick Beaudoin,
  4. Kim N. Holland and R. Dean Grubbs, “Fish Visitors to Seamounts: Tunas and Billfish at Seamounts,” in Seamounts: Ecology, Fisheries, & Conservation, eds. Tony J. Pitcher et al. (Oxford: Blackwell Publishing, 2007), 189–201; Feodor Litvinov, “Fish Visitors to Seamounts: Aggregations of Large Pelagic Sharks Above Seamounts,” in Seamounts: Ecology, Fisheries, & Conservation, eds. Tony J. Pitcher et al. (Oxford: Blackwell Publishing, 2007), 202–06.
  5. Malcolm R. Clark et al., “The Ecology of Seamounts: Structure, Function, and Human Impacts,” Annual Review of Marine Science 2 (2010): 253–78,

Spotlight on Mental Health

Composite image of modern city network communication concept

Learn the Basics of Broadband from Our Limited Series

Sign up for our four-week email course on Broadband Basics

Quick View

How does broadband internet reach our homes, phones, and tablets? What kind of infrastructure connects us all together? What are the major barriers to broadband access for American communities?

Pills illustration
Pills illustration

What Is Antibiotic Resistance—and How Can We Fight It?

Sign up for our four-week email series The Race Against Resistance.

Quick View

Antibiotic-resistant bacteria, also known as “superbugs,” are a major threat to modern medicine. But how does resistance work, and what can we do to slow the spread? Read personal stories, expert accounts, and more for the answers to those questions in our four-week email series: Slowing Superbugs.

Explore Pew’s new and improved
Fiscal 50 interactive

Your state's stats are more accessible than ever with our new and improved Fiscal 50 interactive:

  • Maps, trends, and customizable charts
  • 50-state rankings
  • Analysis of what it all means
  • Shareable graphics and downloadable data
  • Proven fiscal policy strategies


Welcome to the new Fiscal 50

Key changes include:

  • State pages that help you keep track of trends in your home state and provide national and regional context.
  • Interactive indicator pages with highly customizable and shareable data visualizations.
  • A Budget Threads feature that offers Pew’s read on the latest state fiscal news.

Learn more about the new and improved Fiscal 50.