From global sea census, a treasure trove
Tuesday, October 5, 2010
A lone deep-sea snail living within a hot-water fissure on the ocean floor. The migratory tracks of great white sharks crossing ocean basins. Audio recordings of schools of fish the size of Manhattan, swimming in concert.
These are just a handful of the discoveries that came out of the Census of Marine Life, a decade-long project completed Monday. Encompassing more than 2,700 scientists from 80 nations and territories around the world, the census sought to answer a basic but daunting question. In the words of its International Scientific Steering Committee Chairman Ian Poiner: "What did live in the ocean, what does live in the ocean, and what will live in the ocean?"
Ten years after the study was launched, much of the sea remains unknown. At its start, only 5 percent of the ocean had been seriously explored, and even now, there are no observations for 20 percent of it, while more than half of the ocean has been subject to just minimal exploration.
Still, the project has, in the words of co-founder Jesse Ausubel, "defined what is unknown" about the ocean, and shed light on how it functions. "The oceans are richer than we imagined, more connected than we imagined, and they're more altered," said Ausubel, census vice president and program director for the Alfred P. Sloan Foundation.
The $650âmillion initiative, $75 million of which came from the Sloan Foundation, launched 570 expeditions that journeyed from Antarctica to the tropics. Ranking as one of the world's largest scientific collaborations, it produced more than 2,600 academic papers and collected 30 million observations of 120,000 species. Researchers have formally described 1,200 new species and identified about 4,800 others.
The idea for the census developed in the late 1990s. Ausubel and Fred Grassle, of Rutgers University, approached Stanford University marine biologist Barbara Block about coordinating a tagging program in the Pacific Ocean to track where and how key creatures moved underwater. Block, who had tagged animals in the Atlantic, said she walked away from the conversation "a little shellshocked," adding: "I had never worked in the Pacific in a big way."
Tagging of Pacific Predators, the operation that arose from that conversation, is the world's largest tracking of marine animals. Researchers have more than 4,300 electronic tags to study 23 species' positions as well as ocean temperature, pressure, light and salinity, retrieving a billion records from the sea.
Those findings, Block said, should help ensure that institutions and governments are willing to fund this kind of research even now that the census is over.
"This deep ocean can be studied and can be tracked," she said.
Sophisticated tracking has provided some of the most stunning discoveries about the sea over the past decade. A single bluefin tuna crosses the North Atlantic over the course of two years, swimming past the Virginia and Maryland coasts. Loggerhead turtles move through those same waters, but they follow the North Atlantic gyre not just along the East Coast but to Africa and then the Caribbean.
Virginia Institute of Marine Science professor Tracey Sutton used funds from the census and the National Science Foundation to spearhead the Mid-Atlantic Ridge Ecosystem Project, in which scientists from 16 nations studied deep-sea animals along the underwater mountain range that runs from Iceland to the Azores.
The project launched three cruises - in 2003, 2004 and 2009 - to sample organisms living as deep as 9,000 feet below the surface and to monitor the flow of energy through the North Atlantic ecosystem. "Understanding the dynamics of deep-sea food webs is essential for scientific understanding and management of earth's largest ecosystem," Sutton said.