New census finds ocean of marvels

A city of brittle stars off the coast of New Zealand, an Antarctic expressway where octopuses ride a flow of extra-salty water, and a carpet of tiny crustaceans on the Gulf of Mexico sea floor are among the wonders discovered by researchers compiling a massive census of marine life.

“We are still making discoveries,” but researchers also are busy assembling data already collected, senior scientist Ron O'Dor said.

The fourth update of the census was released Sunday ahead of a meeting of hundreds of researchers to begin Tuesday in Valencia, Spain. More than 2,000 scientists from 82 nations are taking part in the project, to be finished in 2010.

A discovery that delights O'Dor is that many deep-ocean octopuses share an Antarctic origin. As the Antarctic got colder, ice increased and octopuses were forced into deeper water, he said.

Salt and oxygen are concentrated in the deeper waters, he said. This dense water then flows out, carrying along the octopuses that have adapted to the new conditions, enabling them to spread to deep waters around the world.

Deep-water octopuses worldwide, he said, lack the ink sack that shallow-water cousins use to shoot out a camouflage screen. If they live where it is dark, ink is unnecessary, noted O'Dor, from Canada.

Patricia Miloslavich, a senior scientist from Venezuela, is pleased with newly discovered mollusks, from snails to cuttlefish to squids.

Once the census is done, the plan is for three books: a popular survey of sea life, a second book with chapters for each working group and a third on biodiversity. O'Dor said also researchers are working with the online scientific journal PLoS ONE, which is open to anyone and thus would make the results readily available.