Giant squid

The giant squid (Architeuthis dux) is a fascinating creature that lives deep in the ocean. It belongs to the family Architeuthidae and is known for its incredible size. Scientists believe the largest females can reach about 5 metres (16 feet) from the posterior fins to the tip of its long arms. While it is longer than the colossal squid, it is not as heavy because its arms take up much of its length.

The main body, called the mantle, of a giant squid is roughly 2 metres (6 feet 7 inches) long. Giant squids also have special feeding tentacles that can stretch up to 10 metres (33 feet). These tentacles help them catch food in the deep sea.

For many years, people wondered how many kinds of giant squid existed. Thanks to genetic research, scientists now think there is likely just one species. In 2004, a team of Japanese researchers made history by capturing the first ever images of a living giant squid in its natural habitat. This amazing discovery gave us a rare glimpse into the mysterious world of these deep-sea giants.

Taxonomy

The giant squid's closest relatives are thought to be four rare species known as "neosquid," which belong to the family Neoteuthidae. Each of these species is unique, having its own separate genus, similar to the giant squid itself. Together, these groups make up the superfamily Architeuthoidea.

Range and habitat

The giant squid lives in all of the world's oceans. It is most often seen near slopes of continents and islands. Places where giant squid have been spotted include the North Atlantic Ocean near Newfoundland, Norway, the northern British Isles, Spain, and the islands of the Azores and Madeira. They are also found in the South Atlantic around southern Africa, the North Pacific near Japan, and the southwestern Pacific around New Zealand and Australia. These squid are rarely seen in very warm or very cold waters.

We think giant squid can be found at many different depths in the ocean, maybe between 300 and 1,000 metres deep, based on where people have caught them and how deep sperm whales dive.

Morphology and anatomy

See also: Squid and Cephalopod

A giant squid has a mantle (torso), eight arms, and two longer tentacles, which are the longest known of any cephalopod. The arms and tentacles give the squid its great length, but it is lighter than its main predator, the sperm whale. The inside of these arms and tentacles have many round suction cups that help it hold onto prey.

Giant squid have small fins at the back of their bodies that help them move. They can move slowly by pushing water out of their siphon, or quickly by jetting water out. They breathe with two large gills inside their mantle. They also have very large eyes, up to about 27 cm (11 in) across, which helps them see in the deep ocean where light is scarce.

Size

See also: Cephalopod size

The giant squid is one of the largest animals alive today, though it is smaller than the colossal squid. While stories of giant squids longer than 20 meters exist, scientists have never found such large specimens. The largest giant squids ever measured are about 12 to 13 meters long for females and around 10 meters for males. Females are also heavier, weighing up to 275 kilograms, while males weigh up to 150 kilograms.

Reproductive cycle

Little is known about the reproductive cycle of giant squid. They are thought to reach sexual maturity at about three years old, with males maturing at a smaller size than females. Females produce large quantities of eggs, sometimes more than 5 kg (11 lb), that are very small, averaging 0.5 to 1.4 mm (0.020 to 0.055 in) long.

Males have a single testis that produces sperm, which moves into a system of glands that create spermatophores. These are stored in a special sac and expelled during mating through a long, prehensile penis. The exact way sperm reaches the egg mass is still debated, but it may be transferred using special sacs called spermatangia that the male injects into the female's arms.

Genetics

Studies of the mitochondrial DNA of giant squid from around the world show very little difference. Out of over 20,000 genetic building blocks, only 181 are different between individuals. This indicates that all giant squids belong to a single species. Ocean currents likely help spread young squid over large areas.

Main article: mitochondrial DNA

Further information: base pairs

Ecology

Giant squid live deep in the ocean and hunt alone. They eat deep-sea fish, like the orange roughy, and other squid. They catch their food with special tentacles and then use a hard beak and a tongue-like organ with tiny teeth to eat it.

Large predators such as sperm whales, pilot whales, and southern sleeper sharks hunt adult giant squid. Young squid may be eaten by other big deep-sea animals. Scientists have also found signs that giant squid sometimes attack and eat other giant squid, possibly because they are competing for food.

Population

Scientists do not know exactly how many giant squid live in the ocean. They make guesses by counting the giant squid beaks found in the stomachs of sperm whales, which are known to eat giant squid. From this, they believe that sperm whales eat millions of giant squid each year, suggesting that there are also millions of giant squid in the ocean. However, getting a precise count remains difficult.

Species

Scientists have debated how many kinds, or species, of giant squid exist. Some think there might be as many as seventeen different species, while others believe there is just one. The names that have been used include Architeuthis dux (the Atlantic giant squid) and many others.

In 2013, researchers at the University of Copenhagen studied the DNA of these squids and found that they are all so similar genetically that they likely belong to just one species found around the world.

Timeline

Main article: List of giant squid specimens and sightings

Ancient stories and legends often spoke of giant sea monsters, which may have been inspired by sightings of giant squid. Aristotle, a Greek thinker from around 300 BC, wrote about a very large squid he called teuthus. Later, Pliny the Elder, a Roman writer, described an enormous squid with a head as big as a barrel and arms stretching 9 meters (30 feet) long.

In the 1850s, a scientist named Japetus Steenstrup began studying these mysterious creatures and gave them the name Architeuthis. In 1861, part of a giant squid was found by a French ship, and in the late 1800s, many giant squid washed ashore in places like Newfoundland and New Zealand.

One famous giant squid, named "Archie," was caught near the Falkland Islands in 2004. It was almost 9 meters (28 feet) long and is now preserved and displayed at the Natural History Museum in London.

In 2004, scientists captured the first-ever pictures of a live giant squid in its natural home in the deep sea near Japan. These pictures showed the squid hunting and grabbing its food with its tentacles. In 2012, scientists finally filmed a live giant squid in the wild, using special cameras and techniques to observe it without disturbing it. Since then, more videos of live giant squid have been recorded, helping scientists learn more about these amazing deep-sea creatures.

Images and video of live animals

Main article: List of giant squid specimens and sightings (2001–2014) § Quest for a live animal

For many years, no one had ever seen a live giant squid in its natural habitat. The first pictures of a live giant squid were taken in 2004 off the coast of Japan. In 2012, scientists captured the first-ever video of a live giant squid in the deep sea. They used special cameras and techniques, including bioluminescence, to film the squid without disturbing it. In 2019, another video of a young giant squid was recorded in the Gulf of Mexico.

Other sightings

Main articles: List of giant squid specimens and sightings (2001–2014) § Quest for a live animal, and List of giant squid specimens and sightings (2015–present)

Since 2012, videos of live giant squid have occasionally been captured near the ocean's surface. Most of these have been of squid that were sick or struggling, often appearing near shorelines.

Aquarium keeping

The giant squid cannot be kept in aquariums because it lives in very deep ocean waters and has special needs. In 2022, a live giant squid was found near the coast of Japan. People tried to bring it to the Echizen Matsushima Aquarium in the city of Sakai, but sadly, the squid did not survive the journey. It was then put on display at the aquarium for people to see.

Cultural depictions

The giant squid has captured people's imaginations for centuries, appearing in many stories and books. It is a key character in famous works like Moby-Dick and Jules Verne's Twenty Thousand Leagues Under the Seas. Other novels such as Ian Fleming's Dr. No, Peter Benchley's Beast, and Michael Crichton's Sphere also feature giant squids, sometimes in movies too.

One popular image shows a giant squid fighting a sperm whale. While this makes for an exciting story, in real life the squid is actually the whale's prey, not an equal fighter.