Census of Marine Life released

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The fourth update of the Census of Marine Life has been released this week to coincide with the World Conference on Marine Biodiversity in Valencia, Spain and reveals an astonishing array of sea life.

Among the finds revealed in this census were a ~city of brittle stars, a 'shark caf', an 'expressway' for octopuses and a carpet of crustaceans.

The census, which was started in 2000, involves over 2000 scientists from 82 nations.

When released in 2010, it will be the worlds first ever marine census documenting over 230,000 known species and filling in the gaps, which have now seen over 95% of the Earths oceans unexplored.

A tagged sturgeon is released. Picture by Fraser River Sturgeon Conservation Society.

30 expeditions in two yearsSince the last census update two years ago, there have been 30 research expeditions alone. 2100 large animals and thousands of smaller ones have been tagged including a single salmon which was tracked over 2500 kilometres.

Scientists have also tracked sharks across many thousands of kilometres to see them spend six months at the White shark caf in the Pacific Ocean. It is not yet known why the sharks visit there but it is thought to be either a part of feeding or reproduction.

In the eight years since the start of the census scientists have uncovered over 5300 likely new species and have built up a huge DNA library including DNA ~barcodes for 7000 species of zooplankton alone.

Among the interesting finds established by this census there have been Sea stars found which can grow over 60cm across, and a newly described mollusc that can grow up to 40cm long - more twice the length of the next largest mollusc in its class.

Census researchers from New Zealand hold giant Macroptychaster sea stars that can reach 60cm across. Picture by the National Institute of Water and Atmospheric Research.

Sea starsThe worlds deepest sea vent has been discovered at more than 4100metres deep, teeming with life and bacterial reefs have been uncovered living entirely without oxygen.

A city of brittle stars was found North of Antarctica consisting of tens of millions of the starfish relatives living cohabiting peacefully on a seamount taller than the tallest building and an entirely undiscovered continent halfway between America and Europe populated with rare or completely new species.

Such is the magnitude of the discoveries made in this census that is now estimated that there may be as many 750,000 species as yet undescribed.

Bathyraja richardsoni filmed on the Mid-Atlantic Ridge. Picture by Nicola King, Oceanlab, University of Aberdeen.

Once the census is complete, the plan is to publish three books: a popular survey of sea life, a second book with chapters for each working group and a third focusing on biodiversity.

The data collected is being published through the open access journal PloS ONE.