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Two-month study of life in mid-Atlantic yields trove of species, new insights & questions

Scientists intrigued by high animal diversity, unfamiliar specimens, planktonic rings, burrows on sea floor, more

Using remotely-operated deep-sea vehicles, hydroacoustics and other technologies for sampling and observation, the Norwegian-led MAR-ECO Expedition (http://www.mar-eco.no), part of the 10-year, $1 billion Census of Marine Life (www.coml.org), has captured or recorded rare and potentially new species of squid and fish, measured the abundance of life, and advanced knowledge of - while raising new questions about - many other aspects of the Mid-Atlantic Ridge ecosystem.

Among the scientists' discoveries and interests:

• The unexpected diversity of animal communities in mid-water and along the bottom in a major section of the global system of mid-oceanic ridges. Thus far recorded, using an arsenal of methods and technologies: about 300 fish species, 50 squids and octopods, and an unknown number of planktonic species yet to be identified;

• Rings of planktonic organisms, observed by echosounders, massed by underwater forces into circular swarms measuring more than 10 km wide, an example of underwater "physical-biological coupling" and thought to be the largest such phenomenon ever recorded;

• Repeated observations of a reef-building, cold-water coral known as Lophelia pertusa. While no major reefs were found, the species was documented for the first time along this section of the mid-Atlantic Ridge;

• New insights into the significance and ecology of the Charlie-Gibbs Fracture Zone, a mid-Atlantic oasis of life, and the Sub-Polar Front.

• A new deep-sea mystery in the form of burrows left by an animal at 2000 meters on a seamount north of the Azores. The lines of evenly-spaced, 5 cm-wide holes create the impression of someone having "used a sewing machine to create this landscape," according to the researchers. While the suspected burrower is a large crustacean or deep-sea blind lobster, several questions linger. "Perhaps each line is a burrow with multiple entries, or is it a succession of burrows with just a single opening, but then how and why can these lines be that straight?" ("Fig. 16." Photo credit: MAR-ECO.)

• Two specimens of the rare Aphyonus gelatinosus, a strange bottom-dwelling, semi-transparent fish covered in a gelatinous layer, recorded only once before in the North Atlantic. ("Fig. 10." Photo credit: David Shale.)

Also among the more than 80,000 specimens collected:

• A deep-sea anglerfish with an unusual head structure and uniquely formed "lure" at the end of the fishing apparatus that sets it apart from other known species ("Fig. 8." Photo credit: Tracey Sutton);

• An unusual member of the Promachoteuthidae family of squids, distinguished by their small heads and small eyes covered with a semi-opaque pseudo-cornea ("Fig. 7". Promachoteuthis megapter. Photo credit Richard Young");

• At least one suspected new species of Ophidophormes, one of the most common deep-sea fish orders ("Fig. 9." Photo credit: Franz Uiblein).

Extensive analyses will be conducted to disprove or verify these and other candidate specimens as new species.

The Norwegian research vessel G.O. Sars arrives at its home port, Bergen, Norway, late Weds. Aug. 4. Project leaders will release preliminary results from their cruise at a news conference at Bergen's Institute of Marine Research, Thurs. Aug. 5 at 3 p.m. local time (2 p.m. BST, 1 p.m. GMT, 9 a.m. EDT). The full media release of current expedition highlights is online at http://www.coml.org/embargo/embargo3.htm

Conducting the expedition, which embarked from Bergen June 5 with a mid-voyage crew change in the Azores: scientists from Austria, Denmark, Faroe Islands, Finland, France, Germany, Iceland, Netherlands, Norway, Portugal, Russia, UK and USA.

MAR-ECO

Co-ordinated by Norway's Institute of Marine Research and the University of Bergen, MAR-ECO is supported by a large number of public and private contributors, listed online at http://www.mar-eco.no/about/sponsors

Census of Marine Life
More than 300 scientists from 53 countries are at work on the Washington DC-based Census of Marine Life, designed to assess the diversity, distribution and abundance of ocean life and explain how it changes over time. The scientists, their institutions and government agencies are pooling their findings to create a comprehensive and authoritative portrait of life in the oceans today, yesterday and tomorrow.

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