This week in London, the Census of Marine Life reported on their ten-year quest to count and document life in the world's oceans.
The discoveries made over the past decade have inspired, surprised and delighted all of us who have been following the work of this epic project, which has dramatically expanded our understanding of the underwater realm. But the Census team ended their work on a humble note, stressing that despite ten years of work, and the coordinated global effort of over 2,700 scientists from more than 600 institutions, who examined every oceanic body on the planet, during 9,000 days at sea on more than 540 expeditions, they have barely scratched the surface of the diversity and strangeness of life in the sea.
"There's a lot of ocean left to explore", says environmental scientist and Census cofounder, Jesse Ausubel.
Dr. Ian Poiner, chair of the Census Steering Committee, underscored the importance of this vast body of research by noting:
"All surface life depends on life inside and beneath the oceans. Sea life provides half of our oxygen and a lot of our food and regulates climate. We are all citizens of the sea. And while much remains unknown, including at least 750,000 undiscovered species and their roles, we are better acquainted now with our fellow travelers and their vast habitat on this globe."
Science News gets to grips with the scale of the work still to do, by observing that according to the Census summary, the tally of 16,764 marine fish species formally named as of early 2010 probably falls short by an estimated 5,000 species. And fish aren't the half of it. They're perhaps 12 percent of the total of marine species, according to the census estimates. Fishes trail after crustaceans and mollusks in number of species, and researchers report evidence of major undercounts in the numbers of recorded species for these other groups too. Overall at least 750,000 marine species, not including microbes, still await discovery, the census teams predict. In the seas, the mysteries easily outnumber known species, now estimated at 250,000.
Deep waters below 200 meters are so under-explored that their life forms constitute "biodiversity's big wet secret," says the census's chief scientist, Ron O'Dor of Dalhousie University in Halifax, Canada. Fewer than 10 percent of records of marine life come from the zone of abyssal plains between 4,000 and 5,000 meters deep, yet that zone accounts for half the oceans' area.