August 8, 2007

Into the Abyss: Our Deepest Oceans Teem With the Strangest Creatures

By Simon Usborne

It was a journey to the bottom of the Gulf of Maine in 2005 that inspired Claire Nouvian to put together an unprecedented showcase of creatures from the bottom of our seas. Plunging down 1,000 metres in a pressurised submersible, she calls the experience the "most incredible moment" of her life. "It was so beautiful and so intense, it changed me for ever."

Two years on, the French wildlife journalist and film director has amassed a gallery of mesmerising finned octopuses, bioluminescent jellyfish and deep-sea "vampires", all of which now appear in her book The Deep.

Estimates put the number of species lurking in our oceans at somewhere between 10 and 30 million (we only know of about 1.4 million species in total, including land animals and birds) and a new species is spotted once a fortnight. On some trips to the deep, 90 per cent of specimens observed are unidentified.

Intent on sharing her passion for the abyss with a wider audience, Nouvian joined forces with some of the world's leading researchers to gather the collection of photographs, some taken by robots capable of descending almost four miles. At those depths, the pressure exerted by water on a body is equivalent to an elephant standing on a person's thumbnail. Nouvian estimates the average cost of an expedition at [pound]15,000 a day.

For Nouvian, the book was itself a voyage of discovery. "A lot of the animals are so rare that they don't have common names," she says. It was difficult to establish with confidence the depths at which rarer species live. "I had to ask every scientist who would have seen each animal. One guy would say, '300 metres', and then someone else would say, 'No way, I saw it with the Russians back in 1979 at 2,000 metres.' There's so much we still don't know."

Every night, billions of creatures swim a thousand metres or so upwards from the darkest depths to the photic zone - the 100 metres of surface water where sunlight penetrates and allows plant life to thrive. They gorge on organisms before returning to the deep, out of sight of predators. "It's the largest synchro-nised animal movement on earth," Nouvian says, "yet before deep-sea exploration we knew hardly anything about it."

The Deep by Claire Nouvian is published by the University of Chicago Press ([pound]23). To order a copy for [pound]21.50 including P&P, call Independent Books Direct on 0870 079 8897

Fanfin seadevil ( Caulophryne jordani)

This 25cm species of anglerfish lurks in hiding at depths of up to 3,000 metres. Anglerfish sport a glowing lure dangling in front of the head. Confusing this "fishing rod" with the bioluminescent bacteria that cling to sinking marine debris, the animal's prey goes in to feed, only to find itself locked in terrifying toothed jaws. Only one per cent of sunlight penetrates below 200m (and none below 1,000m) so animals produce their own light.

Threadfin snailfish ( Careproctus longifilis)

Resembling a prehistoric tadpole, this 15cm fish with a pockmarked face and large protruding eyes has barely evolved in millions of years. It lives more than 2,000 metres down and is sometimes referred to as a living fossil. But it's not the oldest creature in the deep; fossil records of the horseshoe crab and the coelacanth date back more than 250 million years.

Dumbo octopus ( Grimpoteuthis) Researchers have described

14 species of Grimpoteuthis, but most remain enigmatic. This 20cm long Pokemon lookalike has been observed sitting on the sea floor at depths of 300 to 500 metres, with its webbed mantle spread around it. We know that it swims by moving its fins and pulsing its webbed arms, funnelling water for jet propulsion as it searches for snails, worms and other food.

Unidentified species

The iridescent lights on this creature are not an effect of bioluminescence, but the result of light reflecting off rows of tiny "oars" that allow it to move around 2,000 metres down in the ocean. With neither eyes nor even a brain, this creature hunts by dragging its sticky tentacles behind it. Its gaping mouth allows it to accommodate large prey.

Googly-eyed glass squid (Teuthowenia pellucida)

When caught off-guard by passing predators, this squid, which can grow 20cm across and occupy depths of 2,500 metres, undergoes an astonishing transformation. First, it inflates its body with water, swelling into a transparent sphere. If the predator persists, the squid can draw its extremities into its body and, as a last resort, fill itself with black ink so that it disappears into the darkness.

Benthocodon jelly ( Voragonema pedunculata) In 2005, an American submarine

crashed into a mountain under the sea in the Western Pacific. It was 2,000 metres "high" but had never been mapped; it's estimated that there are as many as 50,000 similar sea-mounts in the world's oceans. The currents that flow around them mean they support a huge diversity of life, including this tiny jelly. A strong swimmer for its 4cm girth, it can have 1,000 tentacles, and feeds mainly on tiny crustaceans.

Siphonophore (Marrus orthocanna)

They might not look deadly, but despite having no jaws, teeth or threatening fins, this is one of the deep ocean's most efficient killing machines. The curtain of stinging tentacles it deploys can snare prey 50 metres behind it. It moves by pulsing its swimming bells, and is buoyed by a gas-filled float at the top.

Dumbo octopus ( Grimpoteuthis)

This species occupies the same depths as its diminutive cousin but can grow 1.5 metres long. Its biology and behaviour are largely unknown, except that it spends much of its time on the sea floor, occasionally venturing into shallower waters in search of prey.