Marine census promises first full look at the oceans' teeming life

After 10 years of combing museum collections and lowering cameras, robots, and sonar equipment into the most inaccessible depths of the sea, scientists Monday announced early results of the first-ever attempt to catalog the world's entire population of marine life.

The new Census of Marine Life estimates there are 250,000 known species - and about a million more that have never been discovered.

"Part of what this census has achieved is recognizing the magnitude of what we don't yet know," said oceanographer Sylvia Earle, a former head of the National Oceanic and Atmospheric Administration.

The $650 million project grew from the vision of J. Frederick Grassle, director emeritus of the Institute of Marine and Coastal Sciences at Rutgers University. Back in the late 1990s, Grassle said, he realized that scientists had no comprehensive database of life in the oceans, even as humans were rapidly changing it.

The results are now being seen as an important resource for assessing the impact of oil in the Gulf of Mexico as well as global climate change, ocean acidification, dredging, and the taking of 100 million tons of marine life every year by voracious humans.

"Imagine if we had no idea of what was there before," said Earle, referring to the Deepwater Horizon spill. "How could we possibly imagine the consequences?"

Ten years ago, Earle said, she and most of her colleagues thought that a census of this magnitude could not be taken.

"This is revolutionary," she said. While most people see marine life as "what's cooked on a plate," she said, "the Census of Marine Life helps us see the oceans with new eyes."

Partial results of the census were published Monday by the Public Library of Science in the public-access journal PLoS One; more results will be released in October. Monday's results included information on 185,000 species as well as patterns of diversity over 25 regions around the world.

A dozen papers explain which species are unique to certain regions, which are found around the globe, and which have invaded new territory thanks to human intervention.

The census project began to take shape in the late 1990s, when the United Nations was attempting to establish a treaty to protect global biodiversity.

To look into the situation in U.S. waters, the National Research Council turned to Grassle, a leader in the discovery of a hidden world of life in the sunless environment of deep-sea hydrothermal vents.