The Census of Marine Life is a growing global network of researchers in more than 70 nations engaged in a ten-year initiative to assess and explain the diversity, distribution, and abundance of marine life in the oceans -- past, present, and future.

What lived in the oceans?
What lives in the oceans?
What will live in the oceans?

These questions were the genesis for the Census of Marine Life, a growing global network of researchers in more than 70 nations engaged in a ten-year initiative to assess and explain the diversity, distribution, and abundance of life in the ocean and explain how it changes over time.

Through 2010, scientists worldwide will work to quantify what is known, unknown, and what may never be known about the world's oceans-which comprise more than 70 percent of the Earth's surface and more than 90 percent of its biosphere. Their answers will help identify threatened species and important breeding areas, helping authorities develop effective strategies for the sustainable management of marine resources. New pharmaceuticals and industrial compounds are also among the potential uses of the estimated thousands of undescribed species that will be found. And as the secrets of the planet's last unexplored frontier are revealed, our understanding of elemental processes such as climate, evolution, extinction, and migration will expand.

(Map as of November 2004)

Census Structure
The Census divides itself into three parts. History tells us what live in the ocean. Exploration tells us what lives in the ocean now. And by combining what we learn about historical trends with our knowledge of what lives there now, we can begin to formulate an answer to the core question of what will live in the ocean of tomorrow.

Scientists throughout the world are using historical and environmental archives to construct a picture of the oceans before fishing and to determine the relative impacts of human activities and environmental fluctuations since fishing became important and are compiling this information into a History of Marine Animal Populations. To quantify the diversity, distribution, and abundance of marine life, the Census divides the ocean into parts, with research structured around six realms that encompass life from the surface of the nearshore to the bottom of the deep ocean. Field projects are investigating these ocean realms and depositing their data into the Ocean Biogeographic Information System (OBIS), a web-based catalog of global geo-referenced information on marine species, with on-line tools for visualizing relationships among species and their environment. This massive amount of Census-generated data is being synthesized and mathematical ecosystem models developed to predict changes in Future of Marine Animal Populations caused by environmental or human influences.

Ocean Realms
Since waters and animals move, ocean realms are a means of quantifying what lives in a specific area of the ocean over time. Each of the Census field projects focus on a specific marine region, habitat, or oceanic community and is using a new technology or technique for collecting data on diversity, distribution, and abundance. The field projects include:

• The Human Edges -- nearshore and coastal.
  An international collaboration, NaGISA, which in Japanese means the narrow coastal zone where the land meets the sea, has been formed to inventory and monitor biodiversity in the narrow inshore zone of depths of less than 20 meters. Another project documents the biodiversity and related processes in the Gulf of Maine, a heavily fished ecosystem, with the goal of establishing ecosystem-based management of the area.
  
  
• The Hidden Boundaries -- continental margins and abyssal plains.
  Beyond the coastal zone, continental margins and abyssal plains, hidden beneath the waters, bound the sides and the bottom of the wide oceans. A deep-sea project is undertaking the vast challenge of documenting species diversity of abyssal plains to increase understanding of the historical causes and ecological factors regulating biodiversity and global change.
  
  
• The Central Waters -- light and dark zones.
  The central waters of the ocean fill the vast bowl formed by the hidden boundaries. Two Census projects are tracking animals that move through the light zone of the central waters, the top 200 meters or so where sunlight penetrates. One tracks coastal migrant species, including Salmon, using new electronic tagging technology to create a monitoring network along the entire length of North America's west coast to study the environments and routes of Pacific salmon and other migratory species. A second is investigating the movements of the top predators in the Pacific using electronic tagging technologies that allow researchers to study migration of large open-ocean animals and the oceanographic factors that control them.
  
  Another Census field project is dedicated to increasing our understanding of the ocean's dark zone that extends more than 4000 meters below the surface into pitch-blackness of virtually unexplored territory. Research efforts focus on the huge mountain ranges of the northern Mid-Atlantic, including the processes that control the distribution and community structures of larger marine inhabitants in waters around the Mid-Atlantic Ridge.
  
  
• The Active Geology -- vents and seeps.
  A global study of deep-water vents and seeps from the Earth's core and the processes that drives these isolated ecosystems that serve as nurseries for new species takes scientists to depths of a minimum of 1000 meters below the surface.
  
  
• Other Regions, Habitats, and Oceanic Communities.
  Census projects are also underway to examine microbes, plankton, coral reefs, continental margins, seamounts, the Arctic and Antarctic to increase understanding of all factors that influence biodiversity in the world's seas.

Census Framework
The Census of Marine Life is coordinated by a Secretariat based at the Consortium of Oceanographic Research and Education in Washington, D.C. and governed by several national and regional scientific steering committees. New technologies for observing marine life are monitored by the Scientific Committee on Oceanic Research Working Group, which assesses and recommends when cutting-edge marine technologies are mature enough to be used routinely in Census field projects. All work of the Census is pulled together through its focus on the Known, Unknown, and Unknowable, which determines the strategy for research and discovery of this vast, largely unexplored and undescribed frontier.

Support for the Census of Marine Life comes from government agencies concerned with science, environment, and fisheries in a growing list of nations as well as from private foundations and companies. The Census is associated or affiliated with several intergovernmental international organizations including the Intergovernmental Oceanographic Commission of the UN, the Food and Agriculture Organization of the UN, the UN Environment Programme and its World Conservation Monitoring Centre, the Global Biodiversity Information Facility, the International Council for the Exploration of the Seas, and the North Pacific Marine Science Organization. It is also affiliated with international nongovernmental organizations including the Scientific Committee on Oceanic Research and the International Association of Biological Oceanography of the International Council for Science.