Until now, scientists’ knowledge of the giant squid was based only on murky photographs and the lengthy tentacles of dead specimens washed up on lonely beaches.

Japanese marine biologists, however, have lured a giant squid to the surface of the ocean, off the Ogasawara Islands south of Tokyo, capturing it on camera as it reached out to eat one of its relatives.

They filmed it as they reeled it in. And, according to Tsunemi Kubodera, the team’s leader, it “put up quite a fight”.

It was not quite as long as the largest squid yet recorded — a specimen found in 1887 that measured 18.2m (60ft) from the top of its head to the tip of its tentacles. But the young female was still twice as long as the average person is tall, at 3.5m.

Alas it did not survive the experience. “It took two people to pull it in,” Dr Kubodera said, “and they lost it once, which might have caused the injuries that killed it . . .

“It struggled furiously to escape by spouting water from its funnel. This means they can actually swim pretty fast, in addition to their normal movement just drifting in deep waters,” he said as he showed the film to reporters.

Until the success of the Japanese team, attempts to record a giant squid living in its native environment had ranged from the daring to the ridiculous.

There was a long-term New Zealand project to catch giant squid larvae when they were less than an inch long, in the hope of rearing them in captivity. In 1960 the US Navy organised an expedition to the Mariana trench, the deepest spot on the ocean floor at seven times the depth of the Grand Canyon, in the hope of catching a glimpse of one.

The technology billionaire David Packard funded two underwater robots at the cutting-edge of imaging technology to capture an image of a giant squid. But the closest that his team came to filming one was the accidental capture of 12ft of grasping tentacle in the edge of a fishing net.

So far, the best source of information has been the study of half-digested squid found inside dead whales’ stomachs and tentacle scars on the whales’ vast, barnacled bellies, bearing witness to battles in the depths of the ocean.

Sperm whales in particular, which eat nearly a tonne of food a day, rely on giant squid as a main source of protein. So Dr Kubodera’s team followed pods of sperm whales, monitoring seasonal feeding patterns, in the hope that their search for food would lead them to large groups of giant squid.

They have been tracking squid for three years, and last year managed to capture them underwater in a series of still photographs — the first time that that had been achieved. Having finally caught one, the biologists are keen to analyse the contents of its stomach.

“Now that we know where to find the squid,” Dr Kubodera said, “we think we can be more successful at studying them in the future.”

Since the squid has eyes that can grow to the size of a human head, and tentacles far longer than a London bus, it seems that interest in this mysterious creature, which remains less understood than the dinosaurs, is assured for years to come.

The ancient legend of the Kraken

Squid the size of “floating islands” were once thought to have sank ten British warships that vanished in 1782

Source: Project Gutenberg; Encyclopaedia Brittanica

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