Interesting Science

[February 22, 2007: "Colossal Squid caught in the Ross Sea, Antartica" - see below]

[February 15, 2007: "Hunting behavior of Large Bioluminescent Squid (Video)"]

Original post and video follows:

Tokyo (AP) - A Japanese research team has succeeded in filming a giant squid* live - possibly for the first time - and says the elusive creatures may be more plentiful than previously believed, a researcher said Friday.

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The research team, led by Tsunemi Kubodera, videotaped the giant squid at the surface as they captured it off the Ogasawara Islands south of Tokyo earlier this month. The squid, which measured about 24-feet long, died while it was being caught.

"We believe this is the first time anyone has successfully filmed a giant squid that was alive," said Kubodera, a researcher with Japan's National Science Museum. "Now that we know where to find them, we think we can be more successful at studying them in the future."

Continued at "Japan Researchers Film Live Giant Squid" [Video]

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An earlier BBC News report from 25 Sptember:

Live giant squid caught on camera

A live, adult giant squid has been caught on camera in the wild for the very first time.

Japanese researchers took pictures of the elusive creature hunting 900m down, enveloping its prey by coiling its tentacles into a ball.

The images show giant squid, known as Architeuthis, are more vigorous hunters than has been supposed.

The images, captured in the Pacific Ocean, appear in the journal Proceedings of the Royal Society B.

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Related Technical Papers:

1) First-ever observations of a live giant squid in the wild
By Kubodera T and Mori K.

Proc Biol Sci. 2005 Dec 22;272(1581):2583-6
doi:10.1098/rspb.2005.3158

Abstract

The giant squid, Architeuthis, is renowned as the largest invertebrate in the world and has featured as an ominous sea monster in novels and movies. Considerable efforts to view this elusive creature in its deep-sea habitat have been singularly unsuccessful. Our digital camera and depth recorder system recently photographed an Architeuthis attacking bait at 900m off Ogasawara Islands in the North Pacific. Here, we show the first wild images of a giant squid in its natural environment. Recovery of a severed tentacle confirmed both identification and scale of the squid (greater than 8m). Architeuthis appears to be a much more active predator than previously suspected, using its elongate feeding tentacles to strike and tangle prey.

2) Anatomical basis for camouflaged polarized light communication in squid

Lydia M. Mathger and Roger T. Hanlon

Biology Letters
ISSN: 1744-9561 (Paper) 1744-957X (Online)
Issue: Volume 2, Number 4 / December 22, 2006
Pages: 494 - 496
DOI: 10.1098/rsbl.2006.0542

Abstract

Camouflage is a means to defeat visual detection by predators, whereas visual communication involves a signal that is conspicuous to a receiver (usually a conspecific). However, most intraspecific visual signals are also conspicuous to predators, so that signalling can lead to the serious consequence of predation. Could an animal achieve visual camouflage and simultaneously send a hidden visual message to a conspecific? Here, we present evidence that the polarized aspect of iridescent colour in squid skin is maintained after it passes through the overlying pigmented chromatophores, which produce the highly evolved - and dynamically changeable - camouflaged patterns in cephalopods. Since cephalopods are polarization sensitive, and can regulate polarization via skin iridescence, it is conceivable that they could send polarized signals to conspecifics while staying camouflaged to fish or mammalian predators, most of which are not polarization sensitive.

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*Info on Giant Squid:

Giant squid, once believed to be mythical creatures, are squid of the Architeuthidae family, represented by as many as eight species of the genus Architeuthis. They are deep-ocean dwelling animals that can grow to a tremendous size: recent estimates put the maximum size at 10 meters (34 ft) for males and 13 meters (44 ft) for females from caudal fin to the tip of the two long tentacles (second only to the Colossal Squid at an estimated 14 meters (46 ft), one of the largest living organisms). The mantle length is only about 2 meters (7 ft) in length (more for females, less for males), and the length of the squid excluding its tentacles is about 5 meters (16 ft). In the past there were reported claims of specimens of up to 20 meters (66 ft), but no animals of such size have been scientifically documented. On September 30, 2004, researchers from the National Science Museum of Japan and the Ogasawara Whale Watching Association took the first images of a live giant squid in its natural habitat.[1] Several of the 556 photos were released a year later.

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Colossal Squid caught in the Ross Sea, Antartica

February 22, 2007: "New Zealand fishermen have caught what is expected to be a world-record-breaking colossal squid...

..Jim Anderton of New Zealand's Ministry of Fisheries said the squid, weighing an estimated 450kg (990lb),took two hours to land in Antarctic waters.

Local news said the Mesonychoteuthis hamiltoni was about 10m (33ft) long, and was the first adult colossal squid landed intact.

"I can assure you that this is going to draw phenomenal interest. It is truly amazing," Steve O'Shea from Auckland's University of Technology told local media." [From the BBC UK News Report "NZ fishermen land colossal squid" (adapted)]

If the estimated weight is correct, this colossal squid with "eyes as big as dinner plates" would be about 330 pounds heavier than the next biggest specimen ever found. It was caught by fishermen from the longliner ship San Aspiring (owned by the Sanford Seafood Company) while they were catching Patagonian toothfish (sold under the name Chilean sea bass) in the Ross Sea, Antartica - the date of the catch has not yet been disclosed.

Technorati: japanese, research, team, giant, squid, video, japan, national, science, museum, pacific, ocean, camouflage, colossal

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