Giant squid ‘an active predator’
- This topic is empty.
-
Giant squid ‘an active predator’
by Richard Ingham
A photo released by Dr Tsunemi Kubodera shows an eight metre long Architeuthis attacking prey hung by a rope, white line at left. (National Science Museum, AP)
Paris – Japanese zoologists have made the first recording of a live giant squid, one of the strangest and most elusive creatures in the world.The size of a bus, with vast eyes and a querulous beak, Architeuthis has long nourished myth and literature.
Until now, the only evidence of giant squids was extraordinarily rare – from dead squids that washed up on remote shores or got snagged on a long-line fish hook or from ships’ crews who spotted the deep-sea denizen as it made a sortie near the surface.
But almost nothing was known about where and how Architeuthis lives, feeds and reproduces. And, given the problems of getting down to its home in the ocean depths, no-one had ever obtained pictures of a live one.
Scientists went to extreme lengths, backed by TV companies, to be the first.
Biologists laid a sex trap
In 1997 the US National Geographic Society attached video cameras by a temporary cord to sperm whales in the hope that this would get pictures.
In 2003, New Zealand marine biologists laid a sex trap.
They ground up some squid gonads, believing that the scent would drive male giant squids wild as the creatures migrated through New Zealand waters.
The hope was that a camera would squirt out the pureed genitals and a passing squid, driven into a sexual frenzy, would then mate with the lens – a project that, some may be relieved to hear, never came to fruition.
Breakthrough
The breakthrough has come from Tsunemi Kubodera of the National Science Museum in Tokyo and Kyoichi Mori of the Ogasawara Whale Watching Association.
Writing in a British scientific publication, Proceedings of the Royal Society B, Kubodera and Mori describe how they also used sperm whales as a guide.
Whale watchers on the Ogawara Islands, in the North Pacific, had long noted the migratory patterns of sperm whales, observing in particular how the mammals would gather near a steep and canyoned continental shelf, about 10-15 kilometres southeast of Chichijima Island.
By attaching depth loggers to the whales, the watchers found the creatures made enormous dives of up to 1 000 metres – just at the depths where the giant squid is believed to lurk.
They then set up a special rig, comprising a camera, stroboscope light, timer, depth sensor, data logger and a depth-activated switch attached to two mesh bags filled with a tempting bait of freshly mashed shrimps.
Suspended from floats, the rig was lowered into the water on a nylon line, with flash pictures taken every 30 seconds for the next four to five hours.
At 09:15 on September 30 2004, squids as we know them changed forever.
At that moment, 900 metres down in the Stygian gloom, an eight-metre specimen lunged at the lower bait bag, succeeding only in getting itself impaled on the hook.
For the next four hours, the squid tried to get itself off the hook as the camera snapped away every 30 seconds, gaining not only unprecedented pictures but also precious information about how the squid is able to propel itself.
After a monstrous battle, the squid eventually freed itself, but left behind a giant tentacle on the hook.
When the severed limb was brought up to the surface, its huge suckers were still able to grip the boat deck and any fingers that touched them – testimony indeed to the myths of yore, that spoke of monstrous arms that grabbed ships and hauled them to their doom.
Kubodera and Mori have carried out a DNA test from the tentacle, and the result concurs with that of other samples taken from washed-up squid.
Their deep-sea pictures suggest that the squid is far from being the “sluggish, neutrally buoyant” creature that it has traditionally been deemed to be.
Quite the opposite, say the Japanese duo. It is an active predator that attacks its prey horizontally, and its two long tentacles coil up into a ball after the strike, rather like pythons that rapidly envelop their prey in their sinuous curves.
_____________________________________________________________
Source : http://www.news24.com/News24/Technology/News/0,,2-13-1443_1806965,00.html
-
- Offline
Giant squid ‘an active predator’
by Richard Ingham
A photo released by Dr Tsunemi Kubodera shows an eight metre long Architeuthis attacking prey hung by a rope, white line at left. (National Science Museum, AP)
Paris – Japanese zoologists have made the first recording of a live giant squid, one of the strangest and most elusive creatures in the world.The size of a bus, with vast eyes and a querulous beak, Architeuthis has long nourished myth and literature.
Until now, the only evidence of giant squids was extraordinarily rare – from dead squids that washed up on remote shores or got snagged on a long-line fish hook or from ships’ crews who spotted the deep-sea denizen as it made a sortie near the surface.
But almost nothing was known about where and how Architeuthis lives, feeds and reproduces. And, given the problems of getting down to its home in the ocean depths, no-one had ever obtained pictures of a live one.
Scientists went to extreme lengths, backed by TV companies, to be the first.
Biologists laid a sex trap
In 1997 the US National Geographic Society attached video cameras by a temporary cord to sperm whales in the hope that this would get pictures.
In 2003, New Zealand marine biologists laid a sex trap.
They ground up some squid gonads, believing that the scent would drive male giant squids wild as the creatures migrated through New Zealand waters.
The hope was that a camera would squirt out the pureed genitals and a passing squid, driven into a sexual frenzy, would then mate with the lens – a project that, some may be relieved to hear, never came to fruition.
Breakthrough
The breakthrough has come from Tsunemi Kubodera of the National Science Museum in Tokyo and Kyoichi Mori of the Ogasawara Whale Watching Association.
Writing in a British scientific publication, Proceedings of the Royal Society B, Kubodera and Mori describe how they also used sperm whales as a guide.
Whale watchers on the Ogawara Islands, in the North Pacific, had long noted the migratory patterns of sperm whales, observing in particular how the mammals would gather near a steep and canyoned continental shelf, about 10-15 kilometres southeast of Chichijima Island.
By attaching depth loggers to the whales, the watchers found the creatures made enormous dives of up to 1 000 metres – just at the depths where the giant squid is believed to lurk.
They then set up a special rig, comprising a camera, stroboscope light, timer, depth sensor, data logger and a depth-activated switch attached to two mesh bags filled with a tempting bait of freshly mashed shrimps.
Suspended from floats, the rig was lowered into the water on a nylon line, with flash pictures taken every 30 seconds for the next four to five hours.
At 09:15 on September 30 2004, squids as we know them changed forever.
At that moment, 900 metres down in the Stygian gloom, an eight-metre specimen lunged at the lower bait bag, succeeding only in getting itself impaled on the hook.
For the next four hours, the squid tried to get itself off the hook as the camera snapped away every 30 seconds, gaining not only unprecedented pictures but also precious information about how the squid is able to propel itself.
After a monstrous battle, the squid eventually freed itself, but left behind a giant tentacle on the hook.
When the severed limb was brought up to the surface, its huge suckers were still able to grip the boat deck and any fingers that touched them – testimony indeed to the myths of yore, that spoke of monstrous arms that grabbed ships and hauled them to their doom.
Kubodera and Mori have carried out a DNA test from the tentacle, and the result concurs with that of other samples taken from washed-up squid.
Their deep-sea pictures suggest that the squid is far from being the “sluggish, neutrally buoyant” creature that it has traditionally been deemed to be.
Quite the opposite, say the Japanese duo. It is an active predator that attacks its prey horizontally, and its two long tentacles coil up into a ball after the strike, rather like pythons that rapidly envelop their prey in their sinuous curves.
_____________________________________________________________
Source : http://www.news24.com/News24/Technology/News/0,,2-13-1443_1806965,00.html
- You must be logged in to reply to this topic.