Deep-sea census reveals treasure trove of species that have never seen sunlight

Census of Marine Life scientists have inventoried an astonishing abundance, diversity and distribution of deep sea species that have never known sunlight - creatures that somehow manage a living in a frigid black world down to 5,000 meters below the ocean waves.

Revealed via deep-towed cameras, sonar and other vanguard technologies, animals known to thrive in an eternal watery darkness now number 17,650, a diverse collection of species ranging from crabs to shrimp to worms.

Most have adapted to diets based on meager droppings from the sunlit layer above, others to diets of bacteria that break down oil, sulfur and methane, the sunken bones of dead whales and other implausible foods.

Scientists working on the deep-sea Census number 344 and span 34 nations.

By the time the 10-year Census concludes in October, 2010, the five deep-sea projects will have collectively fielded more than 210 expeditions, including the first ever MAR-ECO voyage in October-November this year, to explore the Mid-Atlantic Ridge south of the Equator, a scientific collaboration between Russia, Brazil, South Africa and Uruguay.

Each voyage is hugely expensive and challenged by often extreme ocean conditions and requirements that have kept the remotest reaches of Neptune's realm impenetrable until recently.

While the collective findings are still being analyzed for release as part of the final Census report to be released in London on October 4, 2010, scientists say patterns of the abundance, distribution and diversity of deep-sea life around the world are already apparent.

"Abundance is mostly a function of available food and decreases rapidly with depth," said Robert S. Carney of Louisiana State University, co-leader of the Census project COMARGE, studying life along the world's continental margins.

"The continental margins are where we find the transition from abundant food made by photosynthesis to darkened poverty. The transitions display the intriguing adaptations and survival strategies of amazing species," said Dr. Carney.

"In the bathy- and mesopelagic zones - the largest 3D deep-sea living space - animals either have to cope somehow with food scarcity or migrate long distances up to find food," said MAR-ECO project leader Odd Aksel Bergstad of University of Bergen.

"Because it provides an oasis of topographical relief in the center of the ocean, we found a high concentration of animals on the Mid-Atlantic Ridge," he added.