Friday, May 02, 2008

Colossal Squid -- PHOTOS

# 1925 – Species was first discovered in the form of two tentacles found in the stomach of a sperm whale.[4]

Colossal Squid

# 1981 – A Russian trawler in the Ross Sea, off the coast of Antarctica, caught a large squid with a total length of 4 metres (13 feet), which was later identified as an immature female of Mesonychoteuthis hamiltoni.[5]

giant Squid new zealand

# 2003 – A complete specimen of a subadult female (photo at right) was found near the surface with a total length of 6 m (20 ft) and a mantle length of 2.5 m (8 ft).[6]

Colossal Squid

# 2005 – A specimen was captured at a depth of 1625 m while taking a toothfish from a longline off South Georgia Island. Although the mantle was not brought aboard, the mantle length was estimated at over 2.5 m, and the tentacles measured 230 cm. The animal is thought to have weighed between 150 and 200 kg.[7]

Colossal Squid genus Mesonychoteuthis

# 2007 – The largest ever specimen, measuring 10 m (33 ft) in length, was captured by a New Zealand fishing boat off Antarctica. It was initially estimated to weigh 450 kg (992 lb). The squid was taken back to New Zealand for scientific study.[8] A study on the specimen later showed that its actual weight was 495 kg (1,091 lb). Scientists at New Zealand's national museum, Museum of New Zealand Te Papa Tongarewa (Te Papa), were at one time considering using an industrial microwave oven to defrost the animal[9] but have since opted for the more conventional approach of thawing the squid in a bath of salt water

Colossal Squid Mesonychoteuthis hamiltoni

This specimen, caught in early 2007, is the largest cephalopod ever recorded.

Antarctic or Giant Cranch Squid

The beak is considerably smaller than some found in the stomachs of sperm whales,[17][18] suggesting there are Colossal Squid much larger than this one

Mesonychoteuthis, a new genus of oegopsid

Mesonychoteuthis, a new genus of oegopsid, Colossal squid out of the freezer

Colossal squid out of the freezer Massive squid may be just a babe

Massive squid may be just a babe

Ein Koloss-Kalmar in der Wanne

NZ's colossal squid to be microwaved

Many sperm whales carry scars on their backs believed to be caused by the hooks of Colossal Squid

Ein Koloss-Kalmar in der Wanne

The Colossal Squid (Mesonychoteuthis hamiltoni, from Greek mesos (middle), onychos (claw), and teuthis (squid)), sometimes called the Antarctic or Giant Cranch Squid, is believed to be the largest squid species. It is the only known member of the genus Mesonychoteuthis. Though it is known from only a few specimens, current estimates put its maximum size at 12–14 metres (39–46 feet) long, based on analysis of smaller and immature specimens, making it the largest known invertebrate.

Unlike the giant squid, whose tentacles are equipped with suckers lined with small teeth, the suckers at the tips of the Colossal Squid's tentacles have sharp swivelling hooks. Its body is wider and stouter, and therefore heavier, than that of the giant squid. Colossal Squids are believed to have a longer mantle than giant squids, although their tentacles are shorter.

The squid exhibits deep-sea gigantism. The beak of Mesonychoteuthis hamiltoni is the largest known of any squid, exceeding that of Architeuthis (giant squid) in size and robustness. The Colossal Squid is also believed to have the largest eyes in the animal kingdom

The squid's known range extends thousands of miles northward from Antarctica to southern South America, southern South Africa, and the southern tip of New Zealand, making it primarily an inhabitant of the entire circumantarctic Southern Ocean

While little is known about the life of this creature, it is believed to hunt prey such as chaetognatha, large fish like the Patagonian toothfish and other squid in the deep ocean using bioluminescence. Based on capture depths of a few specimens, as well as beaks found in sperm whale stomachs, the adult squid ranges at least to a depth of 2200 metres, while juveniles can go as deep as 1000 metres. It is believed to be sexually dimorphic, with mature females generally being much larger than mature males, as is common in many species of invertebrates.

The squid's method of reproduction has not been observed, although some data on their reproduction can be inferred from anatomy. Since males lack an organ called a hectocotylus (a tentacle used in other cephalopods to transfer a spermatophore to the female), they probably use a penis instead, which would be used to directly implant sperm into females.

Many sperm whales carry scars on their backs believed to be caused by the hooks of Colossal Squid. Colossal Squid are a major prey item for Antarctic sperm whales feeding in the Southern Ocean; 14% of the squid beaks found in the stomachs of these sperm whales are those of the Colossal Squid, which indicates that Colossal Squid make up 77% of the biomass consumed by these whales.[2] Many other animals also feed on this squid, including the beaked whales (such as the bottlenose whales), pilot whale, southern elephant seal, Patagonian toothfish, Pacific sleeper shark, and albatross (e.g., the Wandering and Sooty albatrosses). However, beaks from mature adults have only been recovered from those animals large enough to take such prey (i.e., the sperm whale and Pacific sleeper shark), while the remaining predators are limited to eating juveniles or young adults.

On February 22, 2007, it was announced by authorities in New Zealand that the largest known Colossal Squid had been captured. The specimen measured 10 m (33 ft) in length and weighed 495 kg (1,091 lb). Fishermen on the vessel San Aspiring, owned by the Sanford seafood company, caught the animal in the freezing Antarctic waters of the Ross Sea. It was brought to the surface as it fed on an Antarctic toothfish that had been caught off a long line. It would not let go of its prey and could not be removed from the line by the fishermen, so they decided to catch it instead. They managed to envelop it in a net, hauled it aboard and froze it. The specimen eclipsed the previous largest find in 2003 by about 195 kilograms (430 lb).[11][12] The 10 metre squid is still considerably shorter than some estimates have predicted. The specimen was frozen in a cubic metre of water and transported to the Museum of New Zealand Te Papa Tongarewa, New Zealand's national museum.[9][13] Scientists at the museum were considering using a giant microwave to defrost the squid because defrosting the squid at room temperatures would take days and it would be likely for the outside to rot while the core remains frozen.[14] However, they later opted for the more conventional approach of thawing the squid in a bath of salt water.[10][15] Although initially thought to be a male, dissection of the specimen showed it to be a female

Defrosting and dissection, April-May 2008

Thawing and dissection is currently taking place at the Te Papa museum.[10]

Parts of the specimen have been examined:

* The beak is considerably smaller than some found in the stomachs of sperm whales,[17][18] suggesting there are Colossal Squid much larger than this one.[17][18]
* The eye is 27 cm (10.63 in) wide, with a lens 12 cm across. This is the largest eye of any known animal.[1] These measurements are of the partly collapsed specimen: when living the eye was probably 30[16] to 40 cm (12 to 16 in) across.[19]
* Dissection of the specimen revealed ovaries containing thousands of eggs
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posted by u2r2h at Friday, May 02, 2008


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