Monday, October 4, 2010

Secrets of the Ocean

Weird and wonderful creatures of the deep: Decade-long 'sea census' uncovers 6,000 new species of marine creature Now more than 250,000 different sea creatures beneath the waves

A 'riot of species' has been uncovered in the world's oceans by the most comprehensive survey ever conducted of life in the seas, scientists announced today.

But the decade-long Census of Marine Life, the first global attempt to map the wildlife of the oceans, showed many species - from turtles to seabirds and sharks - were in decline in the face of human activity.

Blind Lobster

A blind lobster with bizarre claws belonging to the very rare genus Thaumastochelopsis, previously known only from four specimens of two species in Australia

Dr Ian Poiner, chairman of the project's scientific steering committee said that, from the Poles to tropical waters and the deep sea, there was an abundance of life.

Many discoveries had been made of new life, with around 6,000 potential new species found by the project and the overall estimate of known marine species increasing from 230,000 to nearly 250,000.

One shrimp-like creature, known as Ceratonotus steiningeri, has several spikes and claws and looks intimidating. It was first discovered five years ago three miles beneath the surface off the Atlantic coast of Africa.

It was one of 800 species found in that research trip, said discoverer Pedro Martinez Arbizu, a department head at the German Centre for Marine Biodiversity Research.

He was astonished to find that the tiny creature also was within the cataloguing he'd made earlier 8,000 miles away in the central Pacific.

'We were really very, very surprised about that,' Arbizu said. 'We think this species has a very broad distribution area.'

But after a decade of work researchers warn they could still not reliably estimate the number of species in the oceans, and it is thought there could be at least a million species in the Earth's seas in total.

Some of the 'most beautiful and wonderful' species found in the decade of discovery included a Jurassic shrimp thought to have become extinct 50 million years ago and a crab named the Yeti crab.

The census also included genetically sequencing tiny microbes to tell them apart, and Dr Poiner said there could be as many as one billion different types in the ocean.

The project, which involved more than 2,700 scientists spending a total of 9,000 days at sea on more than 540 expeditions, also used new technology such as tagging fish to see where they were swimming, fitting seals with monitors to record data as they dived and acoustic systems which measured fish populations as large as Manhattan Island.

Discoveries included the revelation that North Atlantic tuna on the eastern US seaboard were the same fish as those off the coast of Spain or in the Mediterranean as they migrated across the ocean.

The census also showed life was found in the most inhospitable places, and was much more connected than previously thought, through genetic relationships between creatures, the movement of species around the oceans and the 'snow' of food falling from the upper layers of the sea into the deep.

Dr Poiner said: 'It's the first time we truly have a global census of marine life, and have a global baseline which we can use to monitor change in the future - be the changes fishing activity, development of emerging energy, extraction of oil and gas, impacts of climate change, warming oceans or oceans becoming much more acidic.'

The census also looked back in time, using historical records of fish catches, sightings and even restaurant menus and photographs of family fishing trips to see what had happened to our seas.

Dr Poiner said that while 'wherever we went, there was a riot of species', many creatures had suffered significant declines.

In some cases, populations had plummeted by 90% from historical baselines, and fish such as swordfish which were being caught now were also much smaller than in the past.

And creatures at the bottom of the food chain known as phytoplankton, near the surface had declined globally, analysis of observations from ocean-going vessels since 1899 showed.

Dr Poiner said: 'Sadly the seas have been changed much more than we expected, these changes occurred much earlier than we expected and occurred quite quickly.'

And he warned that while recoveries were possible, and had occurred in some cases, to restore the population of species such as whales or degraded habitat took much longer than it took to do the damage.

According to the research, numbers of some species have declined within a human generation.

It also revealed that people began catching marine creatures a long time ago and on a much broader scale than previously thought.

The census will not only provide a baseline for measuring change but is already producing data which can be used by policy makers around the globe to introduce conservation efforts and to govern the high seas.

Victor Gallardo from Chile, vice chairman of the scientific steering committee, said: 'A human census is used for many practical purposes, like government allocations of seats in a legislature, or funds for education or healthcare.

'Likewise, this ocean life inventory constitutes a true census which can guide conservation.'

The project has also generated a website, iobis.org, on which anyone can see the distribution of a species in the ocean from a giant database of names and 'addresses' of marine creatures.

And it reveals just how little we still know about the seas, as the Census database has no records at all for around a fifth of the oceans' volume, while vast areas have very few records.

A yeti crab

A hairy-clawed 'yeti crab' is seen in this picture taken in 2006

hydrothermal vent snail

A hydrothermal vent snail found in Suiyo Seamount at the Tokyo Hydrothermal Vent

leafy Seadragon

A leafy Seadragon, Phycodurus eques, which is camouflaged to resemble a piece of drifting seaweed

Polychaete Worm

A polychaete worm found at a whale fall at Sagami Bay, Japan at a depth of 925 metres

Tiny Copepod

A tiny copepod collected from the Atlantic abyss during the DIVA 2 cruise in February/March 2005

Squid Worm

A recently discovered species called a squidworm found in the Celebes sea in Southeast Asia

Ceratonotus steiningeri

The Ceratonotus steiningeri, that was first discovered 5,400 metres deep in the Angola Basin in 2006. Within a year it was also collected in the southeastern Atlantic, as well as as in the central Pacific Ocean

Census Map Show Seafloor Biomass

Census scientists used nearly 200 studies to estimate the biomass on the seafloor globally from bacteria through fish and other large animals. The yellow-to-red zones in the map show seafloor biomass reaching 3 to 10 grams of carbon per square metre

Dr Niel Bruce Studying Specimens

Dr Niel Bruce of the Museum of Tropical Queensland studying specimens in lighted aquarium on Lizard Island Reef in Australia as part of the census

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