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New Study Presents First-Ever Classification of World's Coastal Waters

System Enables Better Planning, Collaboration and Measurement

WASHINGTON  — A new study published today in the journal BioScience presents a first-ever natural classification system of the world’s coastal waters that will help improve priority setting and conservation planning for marine habitats. The report, titled "Marine Ecoregions of the World: a bioregionalization of coast and shelf areas" was written by lead authors Mark Spalding, senior marine scientist at The Nature Conservancy and Helen Fox, marine biologist at World Wildlife Fund, along with coauthors from 10 partner organizations.

The Marine Ecoregions of the World (MEOW) classification system presents scientists, governments and policy-makers with a consistent way to talk about marine habitats and a tool for making more informed decisions, improving collaboration and implementing better conservation on the ground.

"With growing attention to our threatened oceans and coasts, the need for this type of system is enormous" said Spalding. "To date less than one percent of the world’s oceans have been protected, but nations have agreed to ensure widescale protection and sustainable use of our marine resources by 2012. This map will make a great contribution to supporting this task and to tracking progress. It’s critical to have such a scheme to set targets and priorities, to identify gaps and to improve collaboration."

The authors reviewed more than 230 existing publications, worked with 10 partner organizations and gathered input from expert biogeographers from across the globe to devise a consistent and reliable division of the world’s coastal waters. The system divides the planet’s coastal waters of the world into 12 realms (such as the Tropical Atlantic Ocean), 62 provinces (places like the Mediterranean Sea) and 232 ecoregions (smaller and more homogenous units such as the Northern Gulf of Mexico or the Marshall Islands).
"Ever since terrestrial ecoregions were designated, the need to fill in the gaps for marine and freshwater biomes has been highlighted," said Fox. "We’re pleased that the MEOW process did just that for coastal zones in such a collaborative way, and we hope it proves valuable for marine priority setting and planning."

"Creating this system is a tremendous achievement. It not only provides a valuable tool for conservation and natural resources management, but it also shines a bright light onto the tremendous diversity of life in the world’s coastal waters, and on the urgency to act to protect it," added Spalding.

• For instance, in the remote Bijagos Archipelago in the Gulf of Guinea West, marine hippos live in mangrove forests.

• Millions of rare seabirds including albatrosses, shearwaters and penguins crowd together on the volcanic Gough Island in the Southern Atlantic Ocean.

• More than 3,000 different species of fish swim throughout the Coral Triangle.

• Penguins swim around mangrove forests and coral reefs in the Galapagos Islands off the coast of Ecuador.

• In Mauritania, traditional fisherman work alongside wild dolphins to make their catch.

The MEOW system has already been circulated to all nations signed up to the Convention on Biological Diversity. It is being used by the Ramsar Convention on Wetlands, as well as other new studies on global fisheries, marine fish distribution and global marine threats. The World Wildlife Fund and The Nature Conservancy will use this same system as a basis for planning their own large-scale efforts to help protect and manage the world’s coasts and oceans.

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The Nature Conservancy is the leading conservation organization working around the world to protect ecologically important lands and waters for nature and people.  To date, the Conservancy and its more than one million members have been responsible for the protection of more than 15 million acres in the United States and have helped preserve more than 102 million acres in Latin America, the Caribbean, Asia and the Pacific. Visit The Nature Conservancy on the Web at

Known in the United States as World Wildlife Fund and recognized worldwide by its panda logo, WWF leads international efforts to protect endangered species and their habitats and to conserve the diversity of life on Earth. Now in its fifth decade, WWF, the global conservation organization, works in more than 100 countries around the world.