The Giant Squid

Living in the dark, cold depths of the ocean is a creature once though to be myth. We know less about it than we know about the long-extinct dinosaurs. What we know about it comes from the only hundred or so specimens that have ever been found. (7) Architeuthis, better known as the giant squid, is estimated to grow to lengths of over sixty of seventy feet, making it the world’s largest invertebrate. Swift and intelligent, the giant squid has never been observed alive in it’s natural habitat.

Classification
The giant squid belongs to the phylum Mollusca, making it a relative of snails and clams. It is part of the class Cephalopoda (meaning “head-foot”). Cephalopods include squid, octopi, cuttlefish, and the chambered nautilus. The giant squid’s order is Teuthoidea, and it’s family is Loligindae. It’s genus name is Architeuthis, Greek for “chief squid”. Scientists disagree over the number of species of Architeuthis, there may be as few as three or as many as twenty. (8)

Physical Description
Except for a few variations, all squid work basically the same. Despite it’s enormous size, the giant squid is no different. Giant squid have no bones. A feather-shaped blade called a gladius, which is made of chitin (the material insect exoskeletons), provides support and gives muscles a place to attach. The brain is surrounded by cartilage. (9)

The main body of the giant squid is called the mantle. Muscular and bullet-shaped, the mantle houses most of the squid’s organ systems. The mantle is equipped with what is called a funnel or siphon. The funnel is used to suck in and expell water for respiration and propulsion. The funnel is also used for excreting wastes, squirting ink, and laying eggs. Two fins at the rear of the mantle are used for steering and manuevering. In the giant squid these fins are relatively small. (13)

The squid breaths through gills located inside its mantle.

The squid’s head is directly in front of the mantle. The head houses one of the largest and most complex brains of any invertebrate (Cephalopods have been shown in tests to be very intelligent). The giant squid has the largest eye in the animal kingdom, sometimes the size of a dinner plate. Squid have nerve axons so large they were once mistaken for blood vessles, making them prized in neurological research. (1)

The head is also home to a powerful, bird-like beak used for feeding. Inside the beak is a raspy, toothed tongue called a radula. The radula rams food down the esophagus, which passes directly through the brain. (3,6)

Arranged in a circle around the beak are eight arms and two feeding tentacles. The long and muscular arms are covered with rows of powerful suction disks. In some species these suckers have claws or hooks to help hold prey. The two feeding tentacles are nearly twice as long as the arms. The tentacles have broad, leaf-shaped ends covered with suckers. The feeding tentacles are used to catch prey and pull it into the grip of the other eight arms.

The giant squid can change color by the use of chromatosphores, pigment cells is the skin. (11) Some giant squid species may be bioluminescent, like many other species of squid.

The giant squid may have a sensory device like that of fish and amphibian lateral lines, to sense the vibrations of predators or prey. (2)

Giant squid have thin, blue blood that doesn’t carry oxygen well. The blood works even less efficiently in warmer temperatures, and can cause the squid to suffocate in warm water. (11)

The giant squid has one feature no other known squid has. It’s body is full of ammonium ions, which gives it near-nuetral buoyancy in water. (5)

The giant squid is estimated to grow to lengths of sixty feet, while some witnesses claim to have seen squid over a hundred and seventy-five feet.

Habitat
Giant squid are believed to exist throughout the world’s oceans. They live in the lightless depths from 1,000 to 4,000 feet down. (1)

Architeuthis needs to live in cold water, because of their thin, blue blood. Their blood doesn’t carry oxygen well and warm water can cause the squid to suffocate. Warm water might also effect the squid’s buoyancy, causing it to rise to the surface and not be able to get back down. At the surface the water would be even warmer and cause the squid to suffocate. This would explain why most squid beachings occur where warm and cold water currents meet, mostly in Newfoundland. (11)

Reproduction
Male squid produce spermatophores, long tubes filled by millions of sperm. Most species of squid have a modified tentacle for depositing the spermatophores on or in the female. Fertilization occurs internally. The female lays thousands of eggs through the funnel. The developing squid are called paralarva. (9)

Nothing is known of giant squid mating behavior or other specifics of their reproduction.

Movement
The giant squid is jet-propelled. It opens it’s mantle to draw in water, closes the mantle, then forces water out through the funnel. This propels the squid backward at high speeds. (9)

The ammonium ions in the giant squids body allow it to hover silent and motionless in the water.

Feeding
Little is known about the giant squid’s diet except for the stomach contents of dead specimens; deep sea fish and smaller species of squid. (6)

Squid hunt by shooting out their feeding tentacles, which can stretch like bungee cords and are kept coiled when not in use, to grab its prey. The feeding tentacles then draw the prey into the grasp of the other arms, which grip it tightly while the beak tears out chunks of flesh.

Defense
The giant squid has several defensive adaptations. Its huge size alone is enough to protect it from most would-be predators. It only has one known predator, the sperm whale. In the days before whaling was outlawed, every harpooned sperm whale had a stomach full of indigestible squid beaks. (8) Sperm whales have been found with sucker scars the size of hubcaps from battles with squid in the deep.

Architeuthis is not easy prey. It can expel water to shoot away at high speeds. The squid can hover silently, and its soft body may not show up well on whale’s sonar. (6) If confronted with a predator it can eject a cloud of ink out through its funnel from an ink sac to mask its escape.

Behavior
Almost nothing is known about giant squid’s behavior except for what educated guesses can be made based on knowledge of other species of squid, and the stories of sailors and fisherman who claim to have seen it alive.

Giant squid are reportedly aggressive, like many other species of squid ( Three-foot long Humbolt squid have been known to attack and nearly kill people). (4)

There are a few reports of observations of battles between whales and squid. In 1965 a soviet whaler watched as a sperm whale and a giant squid fought near the surface. The battle eventually ended in a draw. The squid’s dying act was to strangle the whale and their bodies were found floating at the surface.

Such battles are often thought to be the result of sperm whales attacking a squid too big for them to handle. Other accounts suggest this might not always be the case.

In October, 1966, two lighthouse keepers at Danger Point, South Africa, observed a baby southern right whale under attack from a giant squid. After a half-hour the squid succeeded in drowning the young whale. (12)

These stories and reports of giant squid attacking ships many times their size suggest that sometimes large squid may take the offensive and attack sperm whales.

Squid and Man
Although they rarely come to the surface, sailors have told tales of giant squid for centuries. In Odyssey, Homer described a monster called a Scylla, whose description is very similar to that of the giant squid.

For centuries tales were told of a monstrous sea creature called the Kraken ( Norwegian for a stump with the roots attached- an apt description of a giant squid). The Kraken was reported to attack and capsize ships, drowning or eating their crew. Today it believed that these tales were true, if not exaggerated (one tale described a beast miles across), stories of giant squid attacks. (11)

It wasn’t until the first documented beached squid carcasses were found in the 1600’s that the sailors stories sounded like anything other than pure fantasy. (7) Since then there have been several recorded encounters between Architeuthis and man.

In 1861 a French corvette attacked a twenty-five foot squid off the island of Tenerife with rifle and cannon fire, the tried to haul it a board. They only got the tail end before the skipper called the whole thing off, “lest the creature damage or injure the ship and the crew.” Zoologist Clyde Roper retorts “How dangerous is a giant squid full of cannon balls going to be?” (3)

In 1874 Reverend Moses Harvey of Newfoundland bought a dead squid caught by fishermen and displayed it as a curiosity. In 1880 A.E. Verril of Yale University used Reverend Harvey’s specimen to carry out the first scientific study and description of the giant squid. (10)

During the 1930’s the Royal Norwegian Navy’s Brunswick, an auxiliary tanker, was attacked at least three times by giant squid. The squid would pull along side the ship and try to grasp the hull. The squid were unable to get a grip on the smooth metal hull. The animals all slid down the length of the ship and were pulled into the propeller and killed. (12)

There are reports from World War II of survivors of sunken ships being menaced by giant squid. One survivor later showed friends and family scars the size of fifty-cent coins where the squid’s suckers had pulled out lumps of flesh.

The United States naval ship Stein was put into dry-dock after its sonar mysteriously malfunctioned. Examination of the sonar dome revealed that it was covered with scratches. Embedded in the dome’s rubber coating were claws like those of the giant squid.

On Christmas Eve in the Philippines, 1989, fishermen recovered twelve survivors hanging onto an overturned boat, as well as the body of a twelve-week old boy. Survivors reported that what looked like a giant octopus attacked and overturned their boat. It then submerged without attacking the survivors. Because octopi are shy bottom-dwellers not known to attack people, it is more likely that the creature was actually a giant squid. (14)

Aside from these accounts man hardly ever encounters the giant squid. Occasionally deep sea fishermen haul up giant squid in their nets but the ammonia in their bodies makes them inedible to humans. (5)

Search for the Giant Squid
Dr. Clyde F. E. Roper, a zoologist with the Smithsonian Institution’s National Museum of Natural History, plans to lead a five-million dollar search for the giant squid. He and other researchers, the “Squid Squad”, hope to be the first to observe the giant squid in its natural habitat by descending in a submersible in the waters off New Zealand. (1)

Roper Plans to use sperm whales as “sea beagles” to point the way to the lair of Architeuthis. Then he will descend in a small submersible with room for two crewman and two observers. Roper, described as Captain Ahab with a Ph.D. (7), is one of the worlds leading authorities on the giant squid.

Roper dismisses stories of giant squid attacks. He doesn’t think that he or the others in the submersible will be in danger.

One of his colleagues, New Zealand fisheries biologist Dr. Ellen C. Foch, has no plans to go down in he submersible. “I have a lot of respect for these animals,” Foch says. “I have two small children at home and they need their mother.” (1)

Conclusion
Fast, stealthy, and smart, Architeuthis is a strange and deadly predator. Rarely seen by humans, it has adaptations that make it at home in the cold, dark depths of the ocean. Thanks to the efforts of scientist like Dr. Clyde Roper, we may learn more about this elusive “chief squid”.

Glossary
1. AXON-an elongated extension of a neuron that carries electrical impulses away form the cell body.
2. BIOLUMENESCENT-an organism that produces light.
3. CARTILAGE-a strong, flexible, connective tissue.
4. CLASS-in taxonomy, a group of similar orders
5. CHROMATOPHORE-pigment cell that expands and contracts, allowing an organism to change colors.
6. CORVETTE-a sloop of war with only one tier of guns; a small vessle used for escort duty.
7. ESOPHAGUS-the tube that connects the mouth with the stomach.
8. FAMILY-in taxonomy, a group of similar genera.
9. FERTILIZATION-the fusion of reproductive cells (ex. egg and sperm).
10. GENUS-in taxonomy, a group of similar species.
11. INVERTEBRATE-an animal with no backbone.
12. LATERAL LINE-a row of sensory structures that detect vibrations.
13. ORDER-in taxonomy, a group of similar families.
14. PIGMENT-coloring matter
15. SPECIES-a group of organisms that are anotomically alike and can produce fetile young.

References

1. Broad, W. J. “Scientist close in on elusive giant squid.” New York Times http://www.ncf.carleton.ca/~bz050/HomePage.archi1.html

2. Budelmann, B. U. “Ulli Budelmann’s home page.” http://cellbio.utmb.edu/budelm/budelm.htm

3. Fisher, A. “He seeks the giant squid.” Poplular Science http://seawifs.gsfc.nasa.gov/OCEAN_PLANET/HTML/ps_roper.html

4. Miller, L. “In search of the giant squid.” Salon http://www.salon1999.com/dec96/squid961202.html

5. Morrison Philip. “Giant against giant in the dark” Scientific American November 1996 http://www.sciam.com/1196issue/1196wonders.html

6. Peterson, J. “Scientist leads deep sea expedition in search of giant squid.” Smithsonian Institution Research Report No. 84 Spring, 1996 http://www.si.edu/resource/topics/research/resrpts/9684/9684-squi.htm

7. Puente, M. “Testing waters to learn more about giant squid.” USA Today 1 Feb. 1996 http://www.ncf.carleton.ca/~bz050/HomePage.usasquid.html

8. Sawyer, Kathy. “Pursuing giant squid in its natural habitat.” The Washington Post http://www.s-t.com/daily/06-96/06-18-96/c03li090.htm

9.. Author unknown. “Squid: the inside story.” http://seawifs.gsfc.nasa.gov/OCEAN_PLANET/HTML/squid_inside.story.html

10. Krystek, Lee. “The kraken.” The Museum of Unatural Mystery http://unmuseum.mus.pa.us/kraken.htm

11. Krystek, Lee. “The giant squid.” The Museum of Unatural Mystery http://unmuseum.mus.pa.us/kraken.htm

12. Author unknown. “Curiosity kills the myth.” http://seawifs.gsfc.nasa.gov./OCEAN_PLANET/HTML/squid_myths.html

13. Author unknown. “In search of the giant squid.” http://weber.u.washington.edu/~bencamp/new.htm.

14. Roersch, Ben S. “Phillipine giant octopus attack.” Denver Post December 27, 1989 http://www.ncf.carleton.ca/goattack.html