"The biggest fishing trip of all time..." --The Guardian

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Posted by s.s. on November 24, 2004 at 02:26:31:

[[similar to story posted on board below, but thought i would include this anyway--happy reading!]]

The biggest fishing trip of all time: $1bn survey unravels mysteries of the deep

'Information seaway' seeks to identify thousands of new species

Tim Radford, science editor
Tuesday November 23, 2004
The Guardian

A billion-dollar survey of the world's oceans has so far pinpointed 38,000 marine species - and identified new fish at the rate of two a week. The census of marine life, a concerted effort by hundreds of scientists from more than 70 nations, is in effect the first hi-tech inventory of life in the so called "blue planet". Oceans cover 70% of the globe. But marine scientists have been pointing out for years that the surface of Venus has been better mapped than the world under the oceans.

The latest "end of term report" by the census scientists assembles data from more than 5.2m new and existing records, and maps the distribution of the 38,000 species. Details of the survey will be unveiled at a meeting in Hamburg next week.

Scientists in Australia, China, Canada, Europe, India, Japan, New Zealand, South America and sub-Saharan Africa are to form nine new regional networks to create a new "information seaway". But the worldwide bid to probe life in the seas has hardly begun.

"We have barely skimmed the surface," said Frederick Grassle, of Rutgers University in the US, who chairs the international scientific steering committee of the census.

"Humans have explored less than 5% of the world's oceans, and even where we have explored, life may have been too small to see. Thus, opportunities abound to discover species and increase our knowledge of abundance and distribution."

Life on earth is a mystery: life in the oceans is an even deeper mystery. The seas cover long sloping continental shelves rich in nutrients that drain from the land; huge, muddy abyssal plains fertilised by detritus from the surface; ocean trenches far deeper than the Grand Canyon, and a vast chain of volcanic mountains known as the mid-Atlantic ridge, where submarine hot springs support colonies of living creatures were discovered only about 25 years ago.

All of these habitats are home to living things.

So far, taxonomists have named and described around 230,000 species of marine creature. But there could be 10 times as many, still to be identified.

At the same time, many ocean species are under threat. Commercial fishing has damaged and depleted the north Atlantic cod and the bluefin tuna and reduced the world's whale population to a hundredth of its original count.

Many of the world's coral reefs - shelter for rich ecosystems of lagoon creatures - are threatened by global warming, habitat destruction and pollution.

The push for new commercial species now threatens deep ocean fish such as the orange roughie, which take decades to reach maturity. As commercial species disappear, so complex ecological networks are disrupted. So the the census is part of a concerted international effort to make a detailed map of life on the biggest - and most unexplored - region of the planet.

The payoff so far is a $9.5m (£5.1m) ocean biographic information system that pinpoints 95% of all records so far on or near the surface of the sea.

Less than 0.1% of the records are from the bottom half of the water column. So there are depths of knowledge still to be plumbed. Researchers calculate that a creature collected from below 2,000 metres is about 50 times more likely to be new to science than one found in the first 50 metres.

In this year alone, the census has added 106 species of marine fish to the database - an average of more than two new species a week. The total of known fish species in the sea now stands at 15,482. There could be another 5,000, awaiting discovery. The database has also counted 6,800 species of zooplankton, animals that drift with the ocean currents. They could identify another 6,000 over the next decade.

The discoveries rest on a whole range of new submarine technologies, from robot submersibles to a network of seafloor "listening posts".

Some scientists have concentrated on collecting specimens from 6,000 metres below the surface, off the coast of Angola, or from the hidden world underneath the Antarctic ice shelf.

Others have "tagged" open ocean species, to provide the first ever map of marine "highways" for sharks, turtles and marine mammals. Biologists have found not just new species of octopus, but a new genus - a much larger grouping - of these puzzling animals in the Southern Ocean. Others have been examining colonies of rhodoliths - a kind of coral-like marine algae that moves like tumbleweed - in southern Alaska. Remotely operated vehicles with robot arms have picked up a clam that survives on methane deposits on the sea floor off the coast of Chile, and a new species of mollusc that lives down thermal vents in the Indian Ocean.

Researchers "listening" to salmon in northern California also picked up signals from tagged green sturgeon - rarest of the 26 sturgeon species - as they travelled to the Canadian coast.

Other researchers have explored not the present but the past, to map the change in sea fish populations.

Records from 400 years ago show that cod taken by hand line from the side of a fishing boat could weigh as much as 80lbs (about 36kg). With the advent of trawl nets, more cod were taken but the average size began to fall dramatically.

Oceanic white tip shark numbers in the Gulf of Mexico have fallen by 99% in the last 50 years. Shark populations in the north Atlantic have fallen by from 40% to 90%, depending on the species. Hardest hit has been a once-feared predator, the hammerhead.

Catches of the day

Biologists identified a new species of grenadier in the Tasman Sea, a new species of scorpionfish in the IndoPacific region and a strange finned octopod they nicknamed "Dumbo" at 3,000 metres on the mid-ocean ridge. But other signals from the seas in the past two years have been less cheerful. These include:

· Carbon-dioxide exhausts from human industry are not just creating warmer oceans, they are gradually increasing their acidity, scientists reported in August. This could affect corals and marine shellfish - and subsequently the species that depend on them.

· American shoppers face an identity crisis. Researchers found in July that 77% of all fish sold in the US as red snapper were in fact some other species.

· Marine biologists have identified a "lost world" in the Arctic ocean. The Canada basin is a vast pool of still water walled in by steep ridges far below the surface. In one cruise, researchers picked up 400 unidentified species.

· In June, British scientists calculated that 30% of the world's seas could be protected from all fishing at a cost of £8bn a year. This is roughly what tourists spend each year on ocean cruises.

· Project Neptune (North-east Pacific time series underwater networked experiments) is to establish a network of 30 sea-floor "laboratories" 100kms apart and up to 3,000 metres deep, connected by 3,000kms of fibre-optic cable. Students will be able to link to the submarine laboratories via the internet.

·The leatherback turtle has outlived the dinosaurs by 65m years. But scientists warned last year that it could be on the road to extinction in 10 to 20 years. Only about 1,500 females now nest in the Pacific.

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