“What surprised me is the beauty.” — JeSSe AuSuBel

First census of marine life reveals zone accounts for half the oceans’ area.

Even though census scientists point

there’s plenty new under the sea out how much remains to be discovered, they did a lot of exploring in 10 years. Of

decade-long study highlights how much more is left to discover ^the ¹⁷ ^teams ^that ^make ^up ^the ^census, ¹⁴emphasized field expeditions, logging more than 9,000 days at sea.

By Susan Milius

The new explorations particularly

A 10-year international boosted knowledge of life at the poles, projectcalledthe Census which aren’t easy places to study, of Marine Life has come Ausubel says. Sending a ship to Antarc-to an end with what has tica costs about $125,000 a day. to be one of the strangest Among all the discoveries from the census reports ever. field, “what surprised me is the beauty,”

At the project’s finale Ausubel says. Census projects encour-in London October 4, a aged photography, and the stream of summary of the work pictures has introduced a wide public to by 2,700 scientists from the charms of deepwater crabs and free-

more than 600 institu- Census photographers captured this hydrozoan jellyfish swimming sea cucumbers (see Page 22). tions around the world in Australia’s Great Barrier Reef, a diversity wonderland. The census also organized records and highlighted their own made them widely available. The Ocean undercounts and the vast realms they report boggling diversity. Analyzing a Biogeographic Information Systemdata-had missed. That, however, was the point. liter of seawater revealed 38,000 kinds base now allows anyone to look up what

“There’s a lot of ocean left to explore,” of microbes, and DNA sequencing in species have been found where. And more says census cofounder Jesse Ausubel, an diverse habitats has turned up speci- than 80,000 species now have their own environmental scientist with the Alfred mens from more than 100 phyla. Such Web pages in the Encyclopedia of Life. P. Sloan Foundation in New York City. breadth approaches three times the Census workers also assessed how The water world covers the majority number of phyla known in the animal human activities such as fishing have of the planet, feeds people far inland, kingdom. Estimatesfor the totalkinds of changed marine populations. Delv-offers exotic compounds for drugs and marine microbes run as high as a billion. ing into documents such as old tax files manufacturing, regulates the planet’s Undersampling afflicts and monastery records, climate and provides half its oxygen, but oceans every where, the researchers found effects its inhabitants remain largely unknown. researchers say. Perhaps as far back as Roman times.

1 million+
estimated number
of species in the
oceans*

How many fish in the sea? The census 80 percent of nonmicrobial O’Dor, however, points out didn’t aim for a full count, since scien- species around Australia that the census also docu-tists haven’t even finished naming known remain undescribed. In the ments recoveries from species of marine fish. According to the Mediterranean, 75 percent human impact. “Under the census, the tally of 16,764 fish species for- of deep-sea species do not right cir cumstances, th e mally named as of early 2010 probably yet have names. ocean is resilient,” he says. falls short by an estimated 5,000 species. Deep waters are so under- Themes of great undiscov-

about 250,000
number of marine
species described to
date*

1,200+
new species
described by Census
of Marine life*

And fish aren’t the half of it. They explored below 200 meters ered diversity at risk aren’t account for perhaps just 12 percent of that their life-forms consti- unique to the sea, says Peter total marine species, the census estimates. tute “biodiversity’s big wet Raven, president emeritus of Crustaceans and mollusks each include secret,” says the census’s the Missouri Botanical Gar-more species than fish, and researchers chief scientist, Ron O’Dor den in St. Louis. “The Cen-report evidence of major undercounts in of Dalhousie University in sus of Marine Life certainly those groups too. Halifax, Canada. Fewer than ought to be replicated on Overall at least 750,000 marine spe- 10 percent of records of land,” he says. “This is basi-cies, not including microbes, still await marine life come from abys- cally an unknown planet discovery, census teams predict. sal plains between 4,000 and when it comes to living For microbes, the census researchers 6,000 meters deep, yet that organisms.”