1. What has lived in oceans?
2. What does live in the oceans?
3. What will live in the oceans?
The Census consists of four major component programs organized around these questions.
Investigating the past
Census researchers undertook the challenge of constructing the history of marine animal populations since human predation became important, roughly the last 500 years. This program component is called History of Marine Animal Populations (HMAP).
Teams of fisheries scientists, historians, economists and others have initiated case studies in southern Africa, Australia, and approximately a dozen other regions. Together, these case studies are creating the first reliable picture of life in the oceans before fishing. This depiction of a more pristine ocean could be important in setting goals for marine protection. The long historical records of marine populations will help distinguish the contributions of natural fluctuations in the environment from the effects of human activities.
Assessing the present
The largest component of the Census involves investigating what now lives in the world's oceans through 14 field projects. Each is sampling important kinds of biota in one of six realms of the global oceans using a range of technologies. Details of these interesting and varied field projects are provided below.
Forecasting the Future
To speak about what will live in the oceans involves numerical modeling and simulation. This component program is organized under the rubric of the Future of Marine Animal Populations (FMAP). This group focuses on integrating data from many different sources and creating new statistical and analytical tools to make predictions for marine populations and ecosystems in the future.
Together, the historical, present, and predictive programs of the Census aim to improve and state as accurately as possible what is known about life in the oceans, to identify what is unknown but knowable, and also to state what may be unknowable.
Providing a Living Legacy
Such a global initiative requires a state-of-the-art data assimilation framework, and this effort, the Ocean Biogeographic Information System (OBIS), forms the fourth component program of the Census. The vision is that users will be able to click on maps of the oceans on their laptop or desktop anywhere in the world and bring up Census data on what is reported to live in the ocean zone of interest. In 2007, OBIS already contains more than 14 million records, with millions more expected by 2010. OBIS is designed to make sharing data easy, opening the door to improved understanding of the patterns and processes that govern marine life.
Six Ocean Realms
To successfully undertake a task as massive as a global census of marine life, the oceans were divided into six realms (with respective sub-zones as necessary), with Census field projects developing efficient approaches for the exploration of each.
These realms were intended to encompass all major ocean systems and taxa, but were also selected to take advantage of the best available technologies. In all Realms, the Census seeks to representatively document diversity, in near surface waters it is tackling distribution, and along the human edges it is demonstrating best practices to estimate abundance. However, recognizing that over 95% of the more than 14 million geographic species records in OBIS are from less than 100 meter depths, it is clear that a quantitative census of all Realms was 'unknowable' in even such an ambitious ten-year program.
The realms are described below.
1. Human Edges
The continental shelves are very gradually sloping borders between the edges of continents and ocean basins. While the shelves comprise only 10 % of ocean areas, they contain most of the known marine biodiversity and lie mainly within the exclusive economic zones of nations. For purposes of the Census, these "Human Edges", from the high tide line to the bottom of the continental shelf, are divided into nearshore and coastal zones.
The census defines the nearshore as the region between the high tide line and 10 meters water depth. The accessible nearshore area has been studied in minute detail in many locales around the world. The nearshore, however, stretches for more than a million kilometers around all oceans and across latitudes and climates. Testing nearshore ecological hypotheses requires that researchers use similar methods in nearshore areas across all latitudes, climates, and ecosystems. This linkage is accomplished in the field project Natural Geography in Shore Areas (NaGISA - "coastal environment" in Japanese). NaGISA's goal is to assess, visualize, and explain nearshore biodiversity patterns.
Coral reefs are another nearshore system under investigation. The global Census of Coral Reefs (CReefs) field project is national (Australia, USA), regional (Caribbean), and international in scope. Researchers are linked across latitudes and climates with standardized research methods for studying the complex habitats created by corals, analogous to those of NaGISA, to assess, visualize, and explain diversity patterns before such patterns are further affected by global changes.
One coastal field project, the Gulf of Maine Area Program (GoMA) is designed to identify and collect the biological knowledge necessary for ecosystem-based management in a large marine environment. GoMA integrates policy and science perspectives and represents a bi-national collaboration between the Canadian Department of Fisheries and Oceans (DFO) and the U.S. National Oceanic and Atmospheric Administration (NOAA). Both governments are sharing costs and data to create the Gulf of Maine Biogeographic Information System (GMBIS).
Another coastal project is the Pacific Ocean Shelf Tracking Project (POST). Its goal is to build a permanent acoustic tracking array for juvenile Pacific salmon and other species as small as 10 g along the west coast of North America, which will serve as a prototype for other coasts.
POST's legacy will be an international network of listening devices stretching from the shore to the edge of the shelf along a continent, serving as a stimulus for similar systems on many of the other continental shelves.
2. Hidden Boundaries
The Census is investigating regions for which there is little prior biological data. The slope region of continental margins that begins at the edge of the continental shelf and extends to ocean basins are considered in the Hidden Boundaries category because they are difficult to sample and little studied.
The deep sea floor below the base of the continental slope covers 30% of the Earth's surface, more than the total continental mass (29%). This region, from approximately 4000 to 6000 meters in water depth, has large areas of flat plains and is called the abyssal plain. Ridges and rises often confine these plains. If the ridge or rise is high enough to prevent the exchange of water with surrounding basins, the deep dwelling marine life there is isolated. Very little is known about this life in the abyssal plain regions. Hence, they are included in the Hidden Boundaries realms.
The Census project, Continental Margin Ecosystems (COMARGE) is establishing biodiversity baselines in margin areas worldwide that are still untouched by commercial exploitation. COMARGE is collecting evidence of changes from commercial activities in the vast Slope Zone, and determining the slope's role in the evolution and distribution of species in continental margin zones above and below.
Valuable synergy exists between COMARGE participants and interests of other Census field projects, including those related to hydrothermal vents, the deep sea, and microbes. Collectively, these efforts will help to identify and describe many new species that will be discovered in this poorly studied realm. Since the major interest in and access to the Slope Zone stems from oil exploration, the initial focus is on benthic ecology and diversity.
The Census of Diversity of Abyssal Marine Life (CeDAMar) was launched to study abyssal plain biodiversity of the endo-, epi-, and hyperbenthic organisms (those living in, on or directly above the sediment). CeDAMar has successfully unified significant Abyssal Plain projects in major ocean basins. It has taxonomists gathering data on species assemblages of single ocean basins and on the large-scale distribution of species. CeDAMar has established standardized sampling protocols for the study of deep-sea biodiversity. Its databases are designed to serve as a benchmark well into the future.
3. Central Waters
The ocean basins and open deep water are between the continental margins. This region is characterized by the Census as Central Waters. These large open ocean areas are home to at least 40% of the world's primary production of biomass. The Census has divided the Central Waters into the Light Zone, from the ocean surface to 200 m water depth, and the Dark Zone, from 200 m to the ocean floor.
Light Zone (drifters and swimmers)
The focus of study on the organisms that drift in the Light Zone is the question of whether this community is consistent globally. This question requires molecular tools and global assessment of populations throughout the ocean. In contrast, there is no question about the basin-wide or even global connections among the large swimming pelagic animals in the Light Zone. New technologies are making it possible to provide realistic estimates of the global distribution and abundance in this realm. Although many of the tracked species also spend time in the Dark Zone, they are being categorized in the Light Zone realm where they typically feed.
The Census of Marine Zooplankton
(CMarZ) was undertaken to accomplish global-scale analysis of all marine zooplankton groups using new and emerging technologies including molecular, optical, and acoustical imaging, and remote detection. Efforts are focused on DNA barcoding of existing specimen collections to identify cryptic species among cosmopolitan groups. CMarZ is working toward a taxonomically comprehensive assessment of animal plankton biodiversity throughout the world ocean.
At the other end of the spectrum is the Tagging of Pacific Predators (TOPP), which is working with marine animals to create a view of vast open ocean habitats as seen by the animals themselves, especially top predators. Knowing the behavior of the top predators allows inferences about the distribution and abundance of many other organisms that live in the ocean, such as where prey species accumulate. By 2010, TOPP will have produced a unique, integrated overview of open ocean biology in the Pacific, and will have aided efforts around the world.
Dark Zone (mid-water and bottom-water)
The challenge of investigating the Dark Zone has been taken on by a multi-national group of researchers who formed the Mid-Atlantic Ridge Ecosystems Project (MAR-ECO). The objective of MAR-ECO is to explore and understand the distribution, abundance, and trophic relationships of the organisms inhabiting the middle and deep waters of the mid-oceanic North Atlantic, and identify and model ecological processes that cause variability in these patterns. By 2010, MAR-ECO will have provided a wealth of information enhancing our understanding of the species, communities and ecosystems of the Mid-Atlantic Ridge and associated waters and set a technological example for other regions.
4. Active Geology
Seamounts, hydrothermal vents, and cold seeps are geologically active areas, grouped together in the Active Geology realm. The Census project, Biogeography of Deep-Water Chemosynthetic Ecosystems (ChEss), was launched to discover new hydrothermal vents and cold seeps, to assess the diversity, distribution, and abundance of their fauna in relation to other chemosynthetic ecosystems, and to explain the differences and similarities at the global scale. By 2010, ChEss will have substantially increased the number of known vents and seeps. It will have discovered new species in chemosynthetic environments and entered assessments of their new and known species diversity, distribution, and abundance into the OBIS database. Beyond these contributions, ChEss will bequeath its example and methods for effective international assessment and explanation of marine life in a specific realm.
The project focusing on seamounts, Census of Seamounts (CenSeam) is synthesizing known biodiversity and directing future field efforts toward a comparative ecology of seamounts. The most efficient sampling strategies and additional existing data resources have been brought into the SeamountsOnline database. The roles seamounts play in the biogeography, biodiversity, productivity, and evolution of marine organisms and their effect on the global oceanic ecosystem should be clarified and quantified by 2010.
5. Ice Oceans - Arctic and Antarctic
Two Census field projects are designed to study the ocean areas at opposite poles of the Earth. They share the need for specially equipped ice breaking ships, forcing highly integrated sampling schedules for the entire water column from surface ice to abyssal plains. The first Ice Ocean field project launched was Arctic Ocean Diversity (ArcOD). Its goal is to assemble existing knowledge of biodiversity in the least known ocean, direct new international explorations using new technologies, and create a framework for understanding and predicting biological changes in this rapidly melting ocean. By 2010, much data will be available on the biogeography of the Arctic to serve as a baseline for anticipated climatic changes.
Like its northern counterpart, the Census of Antarctic Marine Life (CAML) is assembling rich biological data on the Southern Ocean, and encouraging biodiversity sampling on all cruises in the region, particularly during the focal period of the IPY. The goal is to couple this new understanding of biology with the complex current dynamics that control gene flow through the world's oceans.
6. Microbes - The Microscopic Ocean
With more than 20,000 organisms in one liter of seawater, the numbers of microbes in marine environments is staggering and they have a dominating role in ocean processes. To complete a census of marine life, the International Census of Marine Microbes (ICOMM) was established to develop a highly resolved biodiversity database for marine microbes and to understand how microbial populations - the oldest life on the planet - evolve, interact, and redistribute on a global scale.